PIMCO VARIABLE INSURANCE TRUST, 497, 2000-01-14

PIMCO VARIABLE INSURANCE TRUST
497, 2000-01-14

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<PAGE>

P I M C O

PIMCO
Variable
Insurance
Trust Intermediate Duration Bond Portfolios
Total Return Bond Portfolio
High Yield Bond Portfolio

Prospectus

- --------------------------------------------------------------------------------

December 1, 1999
<PAGE>

PIMCO Variable Insurance Trust

Prospectus

December 1, 1999

The PIMCO Total Return Bond and High Yield Bond Portfolios (the "Portfolios"),
which are series of PIMCO Variable Insurance Trust (the "Trust"), are designed
to provide access to the professional investment management services offered
by Pacific Investment Management Company ("PIMCO" or the "Adviser"). Each
Portfolio has its own investment objective and strategies and its own
risk/reward profile, which are described in this Prospectus. The investments
made by the Portfolios at any given time are not expected to be the same as
those made by other mutual funds for which PIMCO acts as investment adviser,
including mutual funds with investment objectives and strategies similar to
those of the Portfolios. Accordingly, the performance of the Portfolios can be
expected to vary from that of the other mutual funds.

This Prospectus gives vital information you should know before investing in
the Portfolios. For your own benefit and protection, please read it before you
invest and keep it for future reference.

Shares of the Portfolios currently are sold to segregated asset accounts
("Separate Accounts") of insurance companies which fund variable annuity con-
tracts and variable life insurance policies ("Variable Contracts"). Assets in
the Separate Account are invested in shares of the Portfolios in accordance
with allocation instructions received from owners of the Variable Contracts
("Variable Contract Owners"). Variable Contract Owners do not deal directly
with the Portfolios to purchase or redeem shares. The allocation rights of
Variable Contract Owners are described in the accompanying Separate Account
prospectus. Shares of the Portfolios also may be sold to qualified pension and
retirement plans outside of the separate account context.

This Prospectus should be read in conjunction with the prospectus of the
Separate Account. Both prospectuses should be read carefully and retained for
future reference.

The Securities and Exchange Commission has not approved or disapproved these
securities or passed upon the accuracy or adequacy of this Prospectus. Any
representation to the contrary is a criminal offense.
<PAGE>

TABLE OF CONTENTS

<TABLE>
<S> <C>
OVERVIEW.................................................................... 3

Portfolios at a Glance.................................................... 3
Investment Strategies and Risk Factors.................................... 3
Fixed Income Instruments.................................................. 3
Ratings of Debt Securities................................................ 4

DESCRIPTION OF PORTFOLIOS................................................... 5

PIMCO Total Return Bond Portfolio......................................... 5
PIMCO High Yield Bond Portfolio........................................... 7

MANAGEMENT OF THE TRUST..................................................... 9

Adviser and Administrator................................................. 9
Advisory and Administrative Fees.......................................... 10
Portfolio Transactions.................................................... 10

PURCHASE OF SHARES.......................................................... 10

REDEMPTION OF SHARES........................................................ 11

NET ASSET VALUE............................................................. 11

TAXES....................................................................... 12

RISK FACTORS AND SPECIAL CONSIDERATIONS..................................... 12

FINANCIAL HIGHLIGHTS........................................................ 18

OTHER INFORMATION........................................................... 19

Portfolio Names........................................................... 19
Total Return.............................................................. 19
Performance Information of Similar Funds.................................. 19

APPENDIX A.................................................................. A-1

APPENDIX B.................................................................. B-1
</TABLE>

Prospectus 2
<PAGE>

OVERVIEW

Portfolios at a Glance

<TABLE>
<CAPTION>
Intermediate
Duration Bond
Portfolios Primary Investments Duration Credit Quality(1) Foreign(2)
- ------------- --------------------------------------- --------- ----------------- ----------
<S> <C> <C> <C> <C>
Total Return Bond Intermediate maturity fixed income 3-6 years B to Aaa; max 10% 0-20%
securities below Baa
High Yield Bond Higher yielding fixed income securities 2-6 years B to Aaa; min 65% 0%
below Baa
</TABLE>
- --------
(1) As rated by Moody's Investors Service, Inc., or if unrated, determined
to be of comparable quality. For specific information concerning the
credit quality of the securities held by each Portfolio, see that
Portfolio's description of Main Investment Strategies.

(2) Percentage limitations relate to foreign currency-denominated
securities. Each Portfolio may invest beyond these limits in U.S.
dollar-denominated securities of foreign issuers.

Investment Strategies and Risk Factors

Investment Strategies. Each Portfolio has specific strategies that it may use
to pursue its investment objective, and specific types of securities in which
the Portfolio may invest, which are described under the heading "Main Investment
Strategies" in the Description of Portfolios. Percentage limitations described
in this Prospectus apply at the time of investment, and may vary with
fluctuations in the value of a Portfolio's investment portfolio.

Risk Factors. The major risks associated with investing in each Portfolio are
described under the heading "Risk Factors" in the Description of Portfolios.
Please be sure to read all risk disclosures carefully before investing. This
Prospectus does not describe all of the risks of every se-curity or technique
that the Portfolios may use. For such information, please refer to the Statement
of Additional Information.

Fixed Income Instruments

"Fixed Income Instruments" as used in this Prospectus means:

. securities issued or guaranteed by the U.S. Government, its agencies or
instrumentalities ("U.S. Government securities");

. corporate debt securities, including convertible securities and corporate
commercial paper;

. mortgage-backed and other asset-backed securities;

. inflation-indexed bonds issued both by governments and corporations;

. structured notes, including hybrid or "indexed" securities, catastrophe
bonds and loan participations;

. delayed funding loans and revolving credit facilities;

. bank certificates of deposit, fixed time deposits and bankers'
acceptances;

. repurchase agreements and reverse repurchase agreements;

. obligations of foreign governments or their subdivisions, agencies and
instrumentalities; and

. obligations of international agencies or supranational entities.

Fixed Income Instruments may have fixed, variable, or floating rates of
interest, including rates of interest that vary inversely at a multiple of a
designated or floating rate, or that vary according to changes in relative
values of currencies. Each of the Portfolios may hold different percentages of
its assets in these various types of securities.

3 PIMCO Variable Insurance Trust
<PAGE>

OVERVIEW (continued)

Ratings of Debt Securities

In this Prospectus, references are made to the ratings of Fixed Income In-
struments. To aid in your understanding of the use of these terms, the follow-
ing is a brief description of the ratings categories applicable to such securi-
ties. For a further description of ratings, see "Appendix B--Description of Se-
curities Ratings."

High Quality Debt Securities are those receiving ratings from at least one
nationally recognized statistical rating organization ("NRSRO"), such as Stan-
dard & Poor's Ratings Services ("S&P") or Moody's Investors Service, Inc.
("Moody's"), in one of the two highest rating categories (the highest category
for commercial paper) or, if unrated by any NRSRO, deemed comparable by PIMCO.

Investment Grade Debt Securities are those receiving ratings from at least
one NRSRO in one of the four highest rating categories or, if unrated by any
NRSRO, deemed comparable by PIMCO.

Lower-Rated, High Yield Securities ("High Yield Bonds") are those rated lower
than Baa by Moody's or BBB by S&P and comparable securities. High yield securi-
ties, which are commonly known as "junk bonds," are considered to be predomi-
nately speculative with respect to the issuer's ability to pay interest and re-
pay principal. For more information on the risks of investing in high yield se-
curities, see "High Yield Securities ("Junk Bonds")" in "Risk Factors and Spe-
cial Considerations."

Prospectus 4
<PAGE>

DESCRIPTION OF PORTFOLIOS

PIMCO TOTAL RETURN BOND PORTFOLIO

Investment Objective

The Total Return Bond Portfolio seeks to maximize total return, consistent
with preservation of capital and prudent investment management.

Main Investment Strategies

The Total Return Bond Portfolio invests under normal circumstances at least
65% of its assets in a diversified portfolio of Fixed Income Instruments of va-
rying maturities. The average portfolio duration of this Portfolio will nor-
mally vary within a three- to six-year time frame based on the Adviser's fore-
cast for interest rates. See "Appendix A--Description of Duration." Portfolio
holdings will be concentrated in areas of the bond market (based on quality,
sector, coupon or maturity) which the Adviser believes to be relatively under-
valued.

The Portfolio may invest up to 10% of its assets in high yield bonds rated B
or higher by Moody's or, if unrated, determined by the Adviser to be of compa-
rable quality. The Portfolio also may invest up to 20% of its assets in securi-
ties denominated in foreign currencies, and may invest beyond this limit in
U.S. dollar-denominated securities of foreign issuers. The Portfolio will hedge
at least 75% of its exposure to foreign currency.

The Portfolio may invest all of its assets in derivative instruments, such as
options, futures contracts or swap agreements, or in mortgage- or asset-backed
securities. The Portfolio may lend its portfolio securities to brokers, dealers
and other financial institutions to earn income. The Portfolio may enter into a
series of purchase and sale contracts or use other investment techniques to ob-
tain market exposure to the securities in which it primarily invests.

Risk Factors

An investment in the Total Return Bond Portfolio is subject to investment
risk, including possible loss of the principal amount invested. The Portfolio
is subject to interest rate risk. Generally, the value of fixed income securi-
ties will change inversely with changes in interest rates. As interest rates
rise, market value tends to de-crease. This risk will be greater for long-term
securities than for short-term securities. Derivative instruments may be par-
ticularly sensitive to changes in prevailing interest rates. The Portfolio also
is subject to credit risk, which is the possibility that an issuer of a securi-
ty, or a counterparty to a derivative contract, will default or become unable
to meet a financial obligation. High yield bonds carry a high degree of credit
risk. Securities of foreign issuers may be subject to additional risk factors,
including foreign currency exchange rate fluctuations, adverse regulatory con-
ditions, foreign taxes, or political or economic uncertainty. For a further ex-
planation, see "Risk Factors and Special Considerations," which you should read
carefully before investing.

An investment in the Portfolio is not a deposit of a bank and is not insured
or guaranteed by the Federal Deposit Insurance Corporation or any other govern-
ment agency.

Performance

The bar chart below shows the actual performance of the Portfolio from incep-
tion. It provides some indication of the variability of the Portfolio's returns
from year to year. The table below shows how the Portfolio's average annual re-
turns for the period indicated compare to those of the Portfolio's benchmark,
the Lehman Brothers Aggregate Bond Index. This is a widely recognized, unman-
aged market index representative of the U.S. taxable fixed income universe. The
bar chart and table do not reflect Variable Contract fees and expenses. If they
did, performance would have been lower. The Portfolio's past performance does
not necessarily indicate how the Portfolio will perform in the future.

[PERFORMANCE CHART APPEARS HERE]

1998
----------
8.61%

Year to date total return through 3/31/99: -0.85%
Best quarter: Q3 '98 5.43%; Worst quarter: Q1 '99 -0.85%

5 PIMCO Variable Insurance Trust
<PAGE>

- --------------------------------------------------------------------------------
Average Annual Total Returns
for the year ended December 31, 1998

<TABLE>
<CAPTION>
1 Year 5 Years 10 Years
<S> <C> <C> <C>
Total Return Bond 8.61% N/A N/A
Lehman Brothers Aggregate Bond Index 8.69% N/A N/A
</TABLE>

Fees and Expenses

The table below describes the fees and expenses (as a percentage of net as-
sets) that you may pay in connection with an investment in the Total Return
Bond Portfolio.

- --------------------------------------------------------------------------------
Annual Portfolio Operating Expenses
(expenses deducted from Portfolio assets)

<TABLE>
<S> <C>
Advisory Fee 0.40 %
Administrative Fee 0.25 %
Other Expenses 0.10 %
-------
Total Portfolio Operating Expenses 0.75 %
Expense Reduction* (0.10)%
------
Net Portfolio Operating Expenses 0.65 %
</TABLE>

* PIMCO has agreed to reduce its administrative fee, subject to potential fu-
ture reimbursement, to the extent that total Portfolio operating expenses would
exceed, due to organizational expenses and the payment by the Portfolio of its
pro rata portion of the Trust's Trustees' fees, 0.65% of average daily net as-
sets.

- --------------------------------------------------------------------------------
Example

This example is intended to help you compare the cost of investing in the
Portfolio with the cost of investing in other portfolios. The example assumes:

. A $10,000 investment for the time periods shown;

. Redemption at the end of each period;

. A hypothetical 5% annual return; and

. Portfolio operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions
your costs would be:

<TABLE>
<CAPTION>
1 Year 3 Years 5 Years 10 Years
<S> <C> <C> <C>
$ 66 $ 208 $ 362 $ 810
</TABLE>

Prospectus 6
<PAGE>

PIMCO HIGH YIELD BOND PORTFOLIO

Investment Objective

The High Yield Bond Portfolio seeks to maximize total return, consistent
with preservation of capital and prudent investment management.

Main Investment Strategies

The High Yield Bond Portfolio invests under normal circumstances at least
65% of its assets in a diversified portfolio of high yield bonds rated at
least B by Moody's or S&P, or, if unrated, determined by the Adviser to be of
comparable quality. The remainder of the Portfolio's assets may be invested in
investment grade Fixed Income Instruments. The average portfolio duration of
this Portfolio will normally vary within a two- to six-year time frame depend-
ing on the Adviser's view of the potential for total return offered by a par-
ticular duration strategy. See "Appendix A--Description of Duration." The
Portfolio may invest in securities of foreign issuers only if the securities
are U.S. dollar-denominated. The Portfolio also may engage in hedging strate-
gies involving equity options.

The Portfolio may invest all of its assets in derivative instruments, such
as options, futures contracts or swap agreements, or in mortgage- or asset-
backed securities. The Portfolio may lend its portfolio securities to brokers,
dealers and other financial institutions to earn income. The Portfolio may en-
ter into a series of purchase and sale contracts or use other investment tech-
niques to obtain market exposure to the securities in which it primarily in-
vests.

Risk Factors

An investment in the High Yield Bond Portfolio is subject to investment
risk, including possible loss of the principal amount invested. The Portfolio
is subject to credit risk. Investments in high yield securities, while gener-
ally providing greater potential opportunity for capital appreciation and
higher yields than investments in higher rated securities, also entail greater
credit risk, including the possibility of default or bankruptcy of the issuer
of the securities. Risk of default or bankruptcy may be greater in periods of
economic uncertainty or recession. The Adviser seeks to reduce credit risk
through diversification, credit analysis and attention to current developments
and trends in both the economy and financial markets. For a further discussion
of the special risks of investing in lower rated securities, see "Risk Factors
and Special Considerations--High Yield Securities ("Junk Bonds")" and "Appen-
dix B--Description of Securities Ratings."

The Portfolio also is subject to interest rate risk. Generally, the value of
fixed income securities will change inversely with changes in interest rates.
As interest rates rise, market value tends to decrease. This risk will be
greater for long-term securities than for short-term securities. Derivative
instruments may be particularly sensitive to changes in prevailing interest
rates. For a further explanation, see "Risk Factors and Special Considera-
tions," which you should read carefully before investing.

An investment in the Portfolio is not a deposit of a bank and is not insured
or guaranteed by the Federal Deposit Insurance Corporation or any other gov-
ernment agency.

Performance

Performance information for this Portfolio is not provided because it has
not been in operation for a full calendar year.

Fees and Expenses

The table below describes the fees and expenses (as a percentage of net as-
sets) that you may pay in connection with an investment in the High Yield Bond
Portfolio.

- -------------------------------------------------------------------------------
Annual Portfolio Operating Expenses
(expenses deducted from Portfolio assets)

<TABLE>
<S> <C>
Advisory Fee 0.50 %
Administrative Fee 0.25 %
Other Expenses 0.06 %
-------
Total Portfolio Operating Expenses 0.81 %
Expense Reduction* (0.06)%
-------
Net Portfolio Operating Expenses 0.75 %
</TABLE>

* PIMCO has agreed to reduce its administrative fee, subject to potential fu-
ture reimbursement, to the extent that total Portfolio operating expenses
would exceed, due to organizational expenses and the payment by the Portfolio
of its pro rata portion of the Trust's Trustees' fees, 0.75% of average daily
net assets.

- -------------------------------------------------------------------------------

7 PIMCO Variable Insurance Trust
<PAGE>

- --------------------------------------------------------------------------------
Example: Expenses on a $ 10,000 Investment

This example is intended to help you compare the cost of investing in the
Portfolio with the cost of investing in other portfolios. The example assumes:

. A $10,000 investment for the time periods shown;

. Redemption at the end of each period;

. A hypothetical 5% annual return; and

. Portfolio operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions
your costs would be:

<TABLE>
<S> <C> <C> <C>
1 Year 3 Years 5 Years 10 Years
$ 77 $ 240 $ 417 $ 930
</TABLE>

Prospectus 8
<PAGE>

MANAGEMENT OF THE TRUST

Adviser and Administrator

PIMCO serves as investment adviser to the Portfolios. PIMCO manages the in-
vestment of the assets of these Portfolios, and places orders for the purchase
and sale of each Portfolio's investments directly with brokers or dealers se-
lected by it in its discretion. See "Portfolio Transactions." PIMCO is one of
the premier fixed income investment management firms in the United States.
PIMCO was founded in 1971, and had over $181 billion in assets under manage-
ment as of September 30, 1999. PIMCO invests in all sectors of the fixed in-
come market using its total return philosophy -- seeking capital appreciation
as well as yield. PIMCO is a subsidiary partnership of PIMCO Advisors L.P. The
general partners of PIMCO Advisors L.P. are PIMCO Partners, G.P. and PIMCO Ad-
visors Holdings L.P. ("PAH"). PIMCO Partners, G.P. is a general partnership
between PIMCO Holding LLC, a Delaware limited liability company and an indi-
rect wholly-owned subsidiary of Pacific Life Insurance Company, and PIMCO
Partners LLC, a California limited liability company controlled by the current
Managing Directors and two former Managing Directors of PIMCO. PIMCO Partners,
G.P. is the sole general partner of PAH. PIMCO's address is 840 Newport Center
Drive, Suite 300, Newport Beach, California 92660. PIMCO is registered as an
investment adviser with the Securities and Exchange Commission ("SEC") and as
a commodity trading advisor with the CFTC.

In selecting fixed income securities, PIMCO uses economic forecasting, in-
terest rate anticipation, credit and call risk analysis, foreign currency ex-
change rate forecasting, and other securities selection techniques. The pro-
portion of each Portfolio's assets committed to investment in securities with
particular characteristics (such as maturity, type and coupon rate) will vary
based on PIMCO's outlook for the U.S. and foreign economies, the financial
markets, and other factors. The management of duration, a measure of a fixed
income security's expected life that incorporates its yield, coupon interest
payments, final maturity and call features into one measure, is one of the
fundamental tools used by PIMCO. For a discussion of the concept of duration,
see "Appendix A--Description of Duration."

The table below provides information about the individual portfolio managers
responsible for management of the Trust's Portfolios, including their occupa-
tions for the past five years.

<TABLE>
<CAPTION>
Portfolio Manager And Business Experience
Portfolio (Past Five Years)
- --------- -----------------------------------------
<C> <S>
Total Return Bond Portfolio William H. Gross, Managing Director, PIMCO. A
Fixed Income Portfolio Manager, Mr. Gross is one
of the founders of PIMCO and has managed the PIMCO
Total Return Fund for the PIMCO Funds: Pacific
Investment Management Series since its inception
on May 11, 1987.

High Yield Bond Portfolio Benjamin Trosky, Managing Director, PIMCO. A Fixed
Income Portfolio Manager, Mr. Trosky joined PIMCO
in 1990 and has managed the PIMCO High Yield Fund
for the PIMCO Funds: Pacific Investment Management
Series since its inception on December 16, 1992.
</TABLE>

PIMCO also serves as administrator to the Portfolios. PIMCO provides admin-
istrative services to the Portfolios which include clerical help, accounting,
bookkeeping, internal audit services, preparation of reports to the Portfo-
lios' shareholders or other appropriate parties, regulatory filings and cer-
tain other services required by the Portfolios.

PIMCO may use its assets and resources, including its profits from advisory
or administrative fees paid by a Portfolio, to pay insurance companies for
services rendered to current and prospective owners of Variable Contracts, in-
cluding the provision of support services such as providing information about
the Trust and the Portfolios, the delivery of Trust documents, and other serv-
ices. Any such payments are made by PIMCO, and not by the Trust, and PIMCO
does not receive any separate fees for such expenses.

9 PIMCO Variable Insurance Trust
<PAGE>

Advisory and Administrative Fees

The Portfolios feature fixed advisory and administrative fee rates. For in-
vestment advisory and administrative services as described below, each Portfo-
lio pays monthly fees at an annual rate based on the average daily net assets
of the Portfolio as follows:

<TABLE>
<CAPTION>
Advisory Fee
Portfolio Rate
--------- ------------
<S> <C>
Total Return Bond Portfolio.................................. 0.40%
High Yield Bond Portfolio.................................... 0.50%
</TABLE>

The administrative fee covers most of the expenses of the Portfolios, in-
cluding legal, audit, custody, transfer agency and certain other services, and
is responsible for the costs of registration of the Trust's shares and the
printing of prospectuses and shareholder reports for current shareholders or
other appropriate parties.

The Portfolios are responsible for bearing certain expenses associated with
their operations that are not provided or procured by PIMCO. While it is ex-
pected that these expenses generally will not have a material effect on the
Portfolio expense ratios, they may have a material effect in certain circum-
stances, such as when the average net assets of a Portfolio are lower than an-
ticipated. PIMCO has contractually undertaken to waive some or all of its ad-
ministrative fee, subject to potential future reimbursement within three years
from the date such fee was waived, as described above in "Description of Port-
folios."

Portfolio Transactions

The Adviser has discretion to select the brokers and dealers with which it
places orders for the purchase and sale of portfolio investments. In doing so,
the Adviser will seek the best price and execution of the Portfolios' orders.
A Portfolio may pay higher commission rates than the lowest available when the
Adviser believes it is reasonable in light of the value of the brokerage and
research services provided by the broker effecting the transaction.

The Adviser manages the Portfolios without regard generally to restrictions
on portfolio turnover. The use of derivative instruments with relatively short
maturities may tend to exaggerate the portfolio turnover rate for some of the
Portfolios. Trading in fixed income securities does not generally involve the
payment of brokerage commissions, but does involve indirect transaction costs.
The use of futures contracts may involve the payment of commissions to futures
commission merchants. A Portfolio with a higher rate of portfolio turnover
will generally incur higher transaction costs.

Some securities considered for investment by the Portfolios also may be ap-
propriate for other clients served by the Adviser. If a purchase or sale of
securities consistent with the investment policies of a Portfolio and one or
more of these clients served by the Adviser is considered at or about the same
time, transactions in such securities will be allocated among the Portfolio
and clients in a manner deemed fair and reasonable by the Adviser. The Adviser
may aggregate orders for the Portfolios with simultaneous transactions entered
into on behalf of other clients of the Adviser.

PURCHASE OF SHARES

As of the date of this Prospectus, shares of the Portfolios are offered for
purchase by Separate Accounts to serve as an investment medium for Variable
Contracts issued by life insurance companies, and to qualified pension and re-
tirement plans outside of the separate account context.

Prospectus 10
<PAGE>

tax treatment or other considerations, it is theoretically possible that the
interest of owners of annuity contracts and insurance policies for which the
Portfolios served as an investment medium might at some time be in conflict.
However, the Trust's Board of Trustees and each insurance company with a sepa-
rate account allocating assets to the Portfolios are required to monitor
events to identify any material conflicts between variable annuity contract
owners and variable life insurance policy owners, and would have to determine
what action, if any, should be taken in the event of such a conflict. If such
a conflict occurred, an insurance company participating in the Portfolios
might be required to redeem the investment of one or more of its separate ac-
counts from the Portfolios, which might force the Portfolios to sell securi-
ties at disadvantageous prices.

The Trust and its distributor each reserves the right, in its sole discre-
tion, to suspend the offering of shares of the Portfolios or to reject any
purchase order, in whole or in part, or to redeem shares, in whole or in part,
when, in the judgment of management, such suspension or rejection is in the
best interests of the Trust. The sale of shares will be suspended during any
period in which the Exchange is closed for other than weekends or holidays, or
if permitted by the rules of the SEC, when trading on the Exchange is re-
stricted or during an emergency which makes it impracticable for the Portfo-
lios to dispose of their securities or to determine fairly the value of their
net assets, or during any other period as permitted by the SEC for the protec-
tion of investors. In the event that a Portfolio ceases offering its shares,
any investments allocated to the Portfolio will, subject to any necessary reg-
ulatory approvals, be invested in another Portfolio.

REDEMPTION OF SHARES

Shares may be redeemed without charge on any day that the net asset value is
calculated. All redemption orders are effected at the net asset value per
share next determined after a redemption request is received. Payment for
shares redeemed normally will be made within seven days.

The Trust may suspend the right of redemption or postpone the payment date
at times when the Exchange is closed, or during certain other periods as per-
mitted under the federal securities laws. In consideration of the best inter-
ests of the remaining shareholders, the Trust reserves the right to pay re-
demption proceeds in whole or in part by a distribution in kind of securities
held by a Portfolio in lieu of cash. It is highly unlikely that shares would
ever be redeemed in kind. If shares are redeemed in kind, however, the redeem-
ing shareholder should expect to incur transaction costs upon the disposition
of the securities received in the distribution.

NET ASSET VALUE

The net asset value per share of each Portfolio is determined once each day
as of 4:00 p.m. Eastern time, or as of such other time designated by the New
York Stock Exchange (the "Exchange") as the close of trading for that day
("closing"). Net asset value will not be determined on any day on which the
New York Stock Exchange is closed. Net asset value is determined by dividing
the total value of a Portfolio's investments and other assets, less any lia-
bilities, by the total outstanding shares of the Portfolio.

11 PIMCO Variable Insurance Trust
<PAGE>

Portfolios intend to use these prices regardless of the impact of any post-
closing adjustments to securities prices, as long as, in the view of the Port-
folios, such prices represent the current market value of the securities as of
the time selected by the Portfolios for the calculation of net asset value.
Portfolios that invest in securities traded in foreign securities markets may
trade such securities on days when the Exchange is not open, and the net asset
value per share of these Portfolios may be affected significantly on days when
investors do not have access to the Portfolios.

Portfolio securities and other assets for which market quotations are read-
ily available are stated at market value. Fixed income securities are normally
valued on the basis of quotations obtained from brokers and dealers or pricing
services. Short-term investments having a maturity of 60 days or less may be
valued at current market value or at amortized cost, when the Board of Trust-
ees determines that amortized cost is their fair value. Certain fixed income
securities for which daily market quotations are not readily available may be
valued, pursuant to guidelines established by the Board of Trustees, with ref-
erence to fixed income securities whose prices are more readily obtainable and
whose durations are comparable to the securities being valued. Subject to the
foregoing, other securities for which market quotations are not readily avail-
able are valued at fair value as determined in good faith by the Board of
Trustees.

TAXES

Each Portfolio intends to qualify as a regulated investment company annually
and to elect to be treated as a regulated investment company for federal in-
come tax purposes. As such, a Portfolio generally will not pay federal income
tax on the income and gains it pays as dividends to its shareholders. In order
to avoid a 4% federal excise tax, each Portfolio intends to distribute each
year substantially all of its net income and gains.

The Portfolios also intend to comply with diversification requirements im-
posed by regulations under Section 817(h) of the Internal Revenue Code, as
amended. Compliance with these diversification rules generally will limit the
ability of a Portfolio to invest greater than 55% of its total assets in di-
rect obligations of the U.S. Treasury (or any other issuer), or to invest pri-
marily in securities issued by a single agency or instrumentality of the U.S.
Government.

If a Portfolio fails to meet the diversification requirement under Section
817(h), income with respect to Variable Contracts invested in the Portfolio at
any time during the calendar quarter in which the failure occurred could be-
come currently taxable to the owners of the Variable Contracts and income for
prior periods with respect to such contracts also could be taxable, most
likely in the year of the failure to achieve the required diversification.
Other adverse tax consequences could also ensue.

Please refer to the prospectus for the Separate Account and Variable Con-
tract for information regarding the federal income tax treatment of distribu-
tions to the Separate Account. See "Additional Information--Additional Tax In-
formation" in the Portfolios' Statement of Additional Information for more in-
formation on taxes.

RISK FACTORS AND SPECIAL CONSIDERATIONS

A Portfolio's risk profile is largely defined by the Portfolio's principal
securities and the investment practices that it uses. You can find a concise
description of each Portfolio's risk profile in the section captioned "De-
scription of Portfolios" in this Prospectus. As with any mutual fund, there is
no guarantee that a Portfolio will earn income or show a positive total return
over any period of time, and you could lose money by investing in the Portfo-
lio.

Prospectus 12
<PAGE>

To the extent that a Portfolio uses these securities or practices, its overall
performance may be affected, either positively or negatively. The following
pages describe certain of the securities in which the Portfolios may invest
and certain of investment practices in which the Portfolios may engage, along
with the risks associated with them. Additional information about these and
other investments and investment practices may be found in the Statement of
Additional Information, which you may obtain free of charge by calling (888)
746-2688.

U.S. Government Securities

U.S. Government securities are obligations of and, in certain cases, guaran-
teed by, the U.S. Government, its agencies or instrumentalities. The U.S. Gov-
ernment does not guarantee the net asset value of the Portfolios' shares. U.S.
Government securities may include zero coupon securities, which do not dis-
tribute interest on a current basis and tend to be subject to greater market
risk than interest-paying securities of similar maturities.

Corporate Debt Securities

The rate of interest paid on a corporate debt security may be fixed, float-
ing or variable, and may vary inversely with respect to a reference rate. See
"Variable and Floating Rate Securities" below. The rate of return or return of
principal on some debt obligations may be linked or indexed to the level of
exchange rates between the U.S. dollar and a foreign currency or currencies.
Investments in corporate debt securities that are rated below investment grade
are described below in "High Yield Securities ("Junk Bonds")." See also, "Ap-
pendix B--Description of Securities Ratings."

Convertible Securities and Equity Securities

A convertible security is a fixed income security that may be converted into
a prescribed amount of common stock at a specified formula. The price of the
convertible security will normally vary in some proportion to changes in the
price of the underlying common stock because of the conversion feature, and as
such is subject to risks relating to the activities of the issuer and/or gen-
eral market and economic conditions. The income component of convertible secu-
rities causes fluctuations based upon changes in interest rates and the credit
quality of the issuer. In addition, convertible securities are often lower-
rated securities. A Portfolio may be required to permit the issuer of a con-
vertible security to redeem the security, convert it into the underlying com-
mon stock, or sell it to a third party, which could have an adverse effect on
a Portfolio's ability to achieve its investment objective.

Although the Portfolios intend to invest primarily in fixed income securi-
ties, each may invest in convertible securities or equity securities. While
some countries or companies may be regarded as favorable investments, pure
fixed income opportunities may be unattractive or limited due to insufficient
supply, or legal or technical restrictions. In such cases, a Portfolio may
consider equity securities or convertible securities to gain exposure to such
investments.

Variable and Floating Rate Securities

Variable and floating rate securities provide for a periodic adjustment in
the interest rate paid on the obligations. Each Portfolio may invest in float-
ing rate debt instruments ("floaters") and engage in credit spread trades. The
interest rate on a floater is a variable rate which is tied to another inter-
est rate, such as a money-market index or Treasury bill rate, and resets peri-
odically. While variable and floating rate securities provide a Portfolio with
a certain degree of protection against rises in interest rates, a Portfolio
will participate in any declines in interest rates as well.

13 PIMCO Variable Insurance Trust
<PAGE>

Inflation-Indexed Bonds

Inflation-indexed bonds are fixed income securities whose principal value is
periodically adjusted according to the rate of inflation. Such bonds generally
are issued at an interest rate lower than typical bonds, but are expected to
retain their principal value over time. The interest rate on these bonds is
fixed at issuance, but over the life of the bond this interest may be paid on
an increasing principal value, which has been adjusted for inflation. If a
guarantee of principal is not provided, the adjusted principal value of the
bond repaid at maturity may be less than the original principal. While these
securities are expected to be protected from long-term inflationary trends,
short-term increases in inflation may lead to a decline in value.

Mortgage-Related and Other Asset-Backed Securities

Each Portfolio may invest all of its assets in mortgage- or other asset-
backed securities. The value of some mortgage- or asset-backed securities in
which the Portfolios invest may be particularly sensitive to changes in pre-
vailing interest rates, and, like other fixed income investments, the ability
of a Portfolio to successfully use these instruments may depend in part upon
the ability of the Adviser to forecast interest rates and other economic fac-
tors correctly.

Mortgage Pass-Through Securities represent interests in "pools" of mortgage
loans secured by residential or commercial real property. Early repayment of
principal on some mortgage-related securities may expose a Portfolio to a
lower rate of return upon reinvestment of principal. Like other fixed income
securities, when interest rates rise, the value of a mortgage-related security
generally will decline; however, when interest rates are declining, the value
of mortgage-related securities with prepayment features may not increase as
much as other fixed income securities. The rate of prepayments on underlying
mortgages will affect the price and volatility of a mortgage-related security,
and may have the effect of shortening or extending the effective maturity of
the security.

Commercial Mortgage-Backed Securities include securities that reflect an in-
terest in, and are secured by, mortgage loans on commercial real property.
Many of the risks of investing in commercial mortgage-backed securities re-
flect the risks of investing in the real estate securing the underlying mort-
gage loans. These risks reflect the effects of local and other economic condi-
tions on real estate markets, the ability of tenants to make loan payments,
and the ability of a property to attract and retain tenants. Commercial mort-
gage-backed securities may be less liquid and exhibit greater price volatility
than other types of mortgage-related or asset-backed securities.

Mortgage-Related Securities include securities other than those described
above that directly or indirectly represent a participation in, or are secured
by and payable from, mortgage loans on real property.

Other Asset-Backed Securities. The Portfolios may invest in other asset-
backed securities that have been or may be offered to investors. For a discus-
sion of the characteristics of some of these instruments, see the Statement of
Additional Information.

Foreign Securities

Each Portfolio may invest directly in fixed income securities of non-U.S.
issuers. The High Yield Bond Portfolio may only invest in U.S. dollar-denomi-
nated fixed income securities of non-U.S. issuers.

Prospectus 14
<PAGE>

expropriation or confiscatory taxation; adverse changes in investment or ex-
change control regulations (which may include suspension of the ability to
transfer currency from a country); and political instability which could af-
fect U.S. investments in foreign countries. Additionally, foreign securities
and dividends and interest payable on those securities may be subject to for-
eign taxes, including taxes withheld from payments on those securities. For-
eign securities often trade with less frequency and volume than domestic secu-
rities and therefore may exhibit greater price volatility. Additional costs
associated with an investment in foreign securities may include higher custo-
dial fees than apply to domestic custodial arrangements and transaction costs
of foreign currency conversions. Changes in foreign exchange rates also will
affect the value of securities denominated or quoted in currencies other than
the U.S. dollar.

The Total Return Bond Portfolio may invest in the securities of issuers
based in countries with developing economies. Investing in developing (or
"emerging market") countries involves certain risks not typically associated
with investing in U.S. securities, and imposes risks greater than, or in addi-
tion to, risks of investing in foreign, developed countries. These risks are
detailed in the Statement of Additional Information.

Foreign Currency Transactions

Foreign currency exchange rates may fluctuate significantly over short peri-
ods of time. The Total Return Bond Portfolio may buy and sell foreign curren-
cies on a spot and forward basis to reduce the risks of adverse changes in
foreign exchange rates. A forward foreign currency exchange contract reduces a
Portfolio's exposure to changes in the value of the currency it will deliver
and increases its exposure to changes in the value of the currency it will ex-
change into. Contracts to sell foreign currency would limit any potential gain
which might be realized by a Portfolio if the value of the hedged currency in-
creases. A Portfolio may enter into these contracts for the purpose of hedging
against foreign exchange risk arising from the Portfolio's investment or an-
ticipated investment in securities denominated in foreign currencies. A Port-
folio also may enter into these contracts for purposes of increasing exposure
to a foreign currency or to shift exposure to foreign currency fluctuations
from one country to another.

The Total Return Bond Portfolio may invest in options on foreign currencies
and foreign currency futures and options thereon. The Portfolio also may in-
vest in foreign currency exchange-related securities, such as foreign currency
warrants and other instruments whose return is linked to foreign currency ex-
change rates. The Portfolio will use these techniques to hedge at least 75% of
its exposure to foreign currency. For a description of these instruments, see
"Derivative Instruments" below and the Statement of Additional Information.

Significant uncertainty surrounds the introduction of the euro (a common
currency for the European Union) in January 1999 and its effect on the value
of securities denominated in local European currencies. These and other cur-
rencies in which the Portfolios' assets are denominated may be devalued
against the U.S. dollar, resulting in a loss to the Portfolios.

High Yield Securities ("Junk Bonds")

Investing in high yield securities involves special risks in addition to the
risks associated with investments in higher rated fixed income securities.
High yield securities may be regarded as predominately speculative with re-
spect to the issuer's continuing ability to meet principal and interest pay-
ments. For more information, see "Appendix B--Description of Securities Rat-
ings." Analysis of the creditworthiness of issuers of high yield securities
may be more complex than for issuers of higher quality debt securities.

15 PIMCO Variable Insurance Trust
<PAGE>

High yield securities may be more susceptible to real or perceived adverse
economic and competitive industry conditions than higher grade securities. The
prices of high yield securities have been found to be less sensitive to inter-
est rate changes than more highly rated investments, but more sensitive to ad-
verse economic downturns or individual corporate developments. If the issuer
of high yield securities defaults, a Portfolio may incur additional expenses
to seek recovery.

The secondary markets on which high yield securities are traded may be less
liquid than the market for higher grade securities, which may adversely affect
and cause large fluctuations in the daily net asset value of a Portfolio's
shares. Adverse publicity and investor perceptions, whether or not based on
fundamental analysis, may decrease the values and liquidity of high yield se-
curities, especially in a thinly traded market.

PIMCO seeks to minimize the risks of investing in high yield securities
through diversification, in-depth credit analysis and attention to current de-
velopments in interest rates and market conditions.

Derivative Instruments

To the extent permitted by the investment objectives and policies of the
Portfolios, the Portfolios may purchase and write call and put options on se-
curities, securities indexes and foreign currencies, and enter into futures
contracts and use options on futures contracts. The Portfolios also may enter
into swap agreements with respect to foreign currencies, interest rates, and
securities indexes. The Portfolios may use these techniques to hedge against
changes in interest rates, foreign currency exchange rates or securities
prices or as part of their overall investment strategies.

The Portfolios may invest all of their assets in derivative instruments,
subject only to the Portfolio's investment objective and policies and any re-
strictions imposed by applicable law. The use of these strategies involves
certain special risks, including a possible imperfect correlation, or even no
correlation, between price movements of derivative instruments and price move-
ments of related investments. While some strategies involving derivative in-
struments can reduce the risk of loss, they can also reduce the opportunity
for gain or even result in losses by offsetting favorable price movements in
related investments or otherwise, due to the possible inability of a Portfolio
to purchase or sell a portfolio security at a time that otherwise would be fa-
vorable, or the possible need to sell a portfolio security at a disadvanta-
geous time because the Portfolio is required to maintain asset coverage or
offsetting positions in connection with transactions in derivative instru-
ments, and the possible inability of a Portfolio to close out or to liquidate
its derivatives positions. The value of some derivative instruments in which
the Portfolios invest may be particularly sensitive to changes in prevailing
interest rates, and, like the other investments of the Portfolios, the ability
of a Portfolio to successfully use these instruments may depend in part upon
the ability of the Adviser to forecast interest rates and other economic fac-
tors correctly. If the Adviser incorrectly forecasts such factors and has
taken positions in derivative instruments contrary to prevailing market
trends, the Portfolios could be exposed to the risk of loss.

Catastrophe Bonds

Each Portfolio may invest in "catastrophe bonds." Catastrophe bonds are
fixed income securities, for which the return of principal and payment of in-
terest is contingent on the non-occurrence of a specific "trigger" event, such
as a hurricane or an earthquake. If a trigger event causes losses exceeding a
specific amount in the geographic region and time period specified in a bond,
a Portfolio investing in the bond may lose a portion or all of its principal
invested in the bond. If no trigger event occurs, the Portfolio will recover
its principal plus interest. Catastrophe bonds may also expose the Portfolio
to certain unanticipated risks including but not limited to issuer (credit)
default, adverse regulatory or jurisdictional interpretation, and adverse tax
consequences.

Prospectus 16
<PAGE>

Temporary Defensive Positions

For temporary, defensive or emergency purposes, the Portfolios may invest
without limit in U.S. debt securities, including short-term money market secu-
rities, when in the opinion of PIMCO it is appropriate to do so. This may
cause a Portfolio to miss investment opportunities and may limit the Portfo-
lio's ability to meet its investment objective. It is impossible to predict
for how long such alternative strategies will be utilized.

Illiquid Securities

The Portfolios may invest up to 15% of their net assets in illiquid securi-
ties. "Illiquid Securities" for this purpose means securities that cannot be
disposed of within seven days in the ordinary course of business at approxi-
mately the amount at which a Portfolio has valued the securities. The Adviser
or Portfolio Manager may be subject to significant delays in disposing of il-
liquid securities and may not be able to dispose of these securities at the
desired time and price. Transactions in illiquid securities may entail addi-
tional registration expenses and other transaction costs.

Year 2000 Readiness Disclosure

Many of the services provided to the Portfolios depend on the smooth func-
tioning of computer systems. Many systems in use today cannot distinguish be-
tween the year 1900 and the year 2000. Should any of the service systems fail
to process information properly, that could have an adverse impact on the
Portfolios' operations and services provided to shareholders. PIMCO, PIMCO Ad-
visors, Custodian, and certain other service providers to the Portfolios have
reported that each is working toward mitigating the risks associated with the
so-called "year 2000 problem." However, there can be no assurance that the
problem will be corrected in all respects and that the Portfolios' operations
and services provided to shareholders will not be adversely effected, nor can
there be any assurance that the year 2000 problem will not have an adverse ef-
fect on the entities whose securities are held by the Portfolios or on domes-
tic or global markets or economies, generally.

17 PIMCO Variable Insurance Trust
<PAGE>

FINANCIAL HIGHLIGHTS

This financial highlights table is intended to help you understand the Port-
folios' financial performance for the period of their operations. Information
is presented for each Portfolio that had investment operations during the re-
porting period. Certain information reflects financial results for a single
portfolio share. The total returns in the table represent the rate that an in-
vestor would have earned or lost on an investment in the Portfolio (assuming
reinvestment of all dividends and distributions). This information has been
audited by PricewaterhouseCoopers LLP, the Portfolios' independent auditors.
Their report, along with full financial statements, appears in the Trust's An-
nual Report, which is available upon request.

<TABLE>
<CAPTION>
Total Return High Yield
Bond Bond
Selected Per Share Data for the Period Ended: Portfolio(a) Portfolio(b)
December 31, 1998 ------------ ------------
<S> <C> <C>
Net asset value, beginning of period................ $10.00 $10.00
Income from Investment Operations
Net investment income(c)............................ 0.56 0.51
Net gains or losses on securities (both realized and
unrealized)(c)..................................... 0.28 (0.34)
Total from investment operations.................... 0.84 0.17
Less Distributions
Dividends (from net investment income).............. (0.56) (0.50)
Distributions (from capital gains).................. (0.19) 0.00
Total distributions................................. (0.75) (0.50)
Net asset value, end of period...................... $10.09 $9.67
Total return (%).................................... 8.61% 1.80%
Ratios/Supplemental Data
Net assets, end of period (000's)................... $3,259 $49,761
Ratio of expenses to average net assets (%)(d)...... 0.65% 0.75%*
Ratio of net investment income to average net
assets (%)(d)...................................... 5.55% 7.90%*
Portfolio turnover rate (%)......................... 138.72% 12.94%
</TABLE>

*Annualized

(a) Commenced operations on December 31, 1997.

(b) Commenced operations on April 30, 1998.

(d) Prior to the waiver and reimbursement of expenses, the ratios of expenses
to average net assets were 0.75% and 0.81% and the ratios of net
investment income to average net assets were 5.45% and 7.84% for the Total
Return Bond and High Yield Bond Portfolios, respectively.

Prospectus 18
<PAGE>

OTHER INFORMATION

Portfolio Names

Each Portfolio considers the various types of debt or fixed income securi-
ties in which it invests, as specifically described in this Prospectus, to be
"bonds" as referenced in that Portfolio's name. The use of this name is not
meant to restrict a Portfolio's investment to the narrow category of debt se-
curities that are formally called "bonds."

Total Return

The "total return" sought by certain of the Portfolios will consist of in-
terest and dividends from underlying securities, capital appreciation re-
flected in unrealized increases in value of portfolio securities, or realized
from the purchase and sale of securities and use of futures and options, or
gains from favorable changes in foreign currency exchange rates. Generally,
over the long term, the total return obtained by a portfolio investing primar-
ily in fixed income securities is not expected to be as great as that obtained
by a portfolio that invests primarily in equity securities. At the same time,
the market risk and price volatility of a fixed income portfolio is expected
to be less than that of an equity portfolio, so that a fixed income portfolio
is generally considered to be a more conservative investment. The change in
market value of fixed income securities (and therefore their capital apprecia-
tion or depreciation) is largely a function of changes in the current level of
interest rates. Generally, when interest rates are falling, a portfolio with a
shorter duration will not generate as high a level of total return as a port-
folio with a longer duration. See "Appendix A--Description of Duration." Con-
versely, when interest rates are rising, a portfolio with a shorter duration
will generally outperform longer duration portfolios. When interest rates are
flat, shorter duration portfolios generally will not generate as high a level
of total return as longer duration portfolios (assuming that long-term inter-
est rates are higher than short-term rates, which is commonly the case). With
respect to the composition of any fixed income portfolio, the longer the dura-
tion of the portfolio, the greater the anticipated potential for total return,
with, however, greater attendant market risk and price volatility than for a
portfolio with a shorter duration. The market value of fixed income securities
denominated in currencies other than the U.S. dollar also may be affected by
movements in foreign currency exchange rates.

The change in market value of equity securities (and therefore their capital
appreciation or depreciation) may depend upon a number of factors, including:
conditions in the securities markets, the business success of the security's
issuer, changing interest rates, real or perceived economic and competitive
industry conditions, and foreign currency exchange rates. Historically, the
total return performance of equity-oriented portfolios has generally been
greater over the long term than fixed income portfolios. However, the market
risk and price volatility of an equity portfolio is generally greater than
that of a fixed income portfolio, and is generally considered to be a more ag-
gressive investment.

Performance Information of Similar Funds

The following table provides information concerning the historical total re-
turn performance of the Institutional Class shares of certain series of PIMCO
Funds: Pacific Investment Management Series ("PIMS"). Each PIMS series has in-
vestment objectives, policies and strategies substantially similar to those of
its respective Portfolio and is currently managed by the same portfolio manag-
er. While the investment objectives and policies of each PIMS series and its
respective Portfolio are similar, they are not identical and the performance
of the PIMS series and the Portfolio will vary. The data is provided to illus-
trate the past performance of the respective Adviser in managing a substan-
tially similar investment portfolio and does not represent the past perfor-
mance of any of the Portfolios or the future performance of any Portfolio or
its portfolio manager. Consequently, potential investors should not consider
this performance data as an indication of the future performance of any Port-
folio or of its portfolio manager.

19 PIMCO Variable Insurance Trust
<PAGE>

The performance data shown below reflects the operating expenses of each
PIMS series, which for all series are lower than the expenses of the corre-
sponding Portfolio. Performance would have been lower for those series if the
Portfolios' expenses were used. In addition, the PIMS series, unlike the Port-
folios, are not sold to Separate Accounts to fund Variable Contracts. As a re-
sult, the performance results presented below do not take into account charges
or deductions against a Separate Account or Variable Contract for cost of in-
surance charges, premium loads, administrative fees, maintenance fees, premium
taxes, mortality and expense risk charges, or other charges that may be in-
curred under a Variable Contract for which the Portfolio serves as an under-
lying investment vehicle. By contrast, Variable Contract Owners with contract
value allocated to the Portfolios will be subject to charges and expenses re-
lating to the Variable Contracts and Separate Accounts.

Each PIMS series' performance data shown below is calculated in accordance
with standards prescribed by the SEC for the calculation of average annual to-
tal return information. The investment results of the PIMS series presented
below are unaudited and are not intended to predict or suggest results that
might be experienced by the PIMS series or the Portfolios. Share prices and
investment returns will fluctuate reflecting market conditions, as well as
changes in company-specific fundamentals of portfolio securities. The perfor-
mance data for the benchmark indices identified below does not reflect the
fees or expenses of the PIMS series or the Portfolios.

Average Annual Total Return for Similar Series of PIMS
and for Benchmark Indices for Periods Ended December 31, 1998

<TABLE>
<CAPTION>
1 3 5 Since Inception
PIMS Series Fund / Benchmark Index Year Years Years Inception Date
- ---------------------------------- ---- ----- ----- --------- ---------
<S> <C> <C> <C> <C> <C>
PIMCO Total Return Fund................... 9.77 8.18 7.89 9.89 5/11/87
Lehman Aggregate Bond/1/................. 8.69 7.29 7.27

PIMCO High Yield Fund..................... 6.54 10.44 10.73 11.97 12/16/92
Lehman BB Int. Corporate/2/.............. 5.74 8.77 9.09
</TABLE>
- --------
/1/ The Lehman Brothers Aggregate Bond Index consists of the Lehman Brothers
Government/Corporate Bond Index, the Lehman Brothers Mortgage-Backed
Securities Index, and the Lehman Brothers Asset-Backed Securities Index.
The Government/Corporate Bond Index consists of the Lehman Brothers
Government Bond Index and the Lehman Brothers Corporate Bond Index. The
Government Bond Index includes all public obligations of the U.S. Treasury
(excluding flower bonds and foreign-targeted issues), its agencies and
quasi-federal corporations, and corporate debt guaranteed by the U.S.
Government. The Corporate Bond Index includes all publicly issued, fixed
rate, non-convertible investment grade U.S. dollar denominated corporate
debt registered with the SEC; it also includes debt issued or guaranteed
by foreign sovereign governments, municipalities, and governmental or
international agencies. The Mortgage-Backed Securities Index consists of
15- and 30-year fixed rate securities backed by mortgage pools of the
Government National Mortgage Association, the Federal Home Loan Mortgage
Corporation and the Federal National Mortgage Association (excluding
buydowns, manufactured homes and graduated equity mortgages). The Asset-
Backed Securities Index consists of credit card, auto and home equity
loans (excluding subordinated tranches) with an average life of one year.
Each Index includes income and distributions but does not reflect fees,
brokerage commissions or other expenses of investing.

/2/ The Lehman Brothers BB Intermediate Corporate Index is an unmanaged market
index comprised of various fixed income securities rated BB. The Index
includes income and distributions but does not reflect fees, brokerage
commissions or other expenses of investing.

Prospectus 20
<PAGE>

APPENDIX A

DESCRIPTION OF DURATION

Duration is a measure of the expected life of a fixed income security that
was developed as a more precise alternative to the concept of "term to maturi-
ty." Traditionally, a fixed income security's "term to maturity" has been used
as a proxy for the sensitivity of the security's price to changes in interest
rates (which is the "interest rate risk" or "volatility" of the security).
However, "term to maturity" measures only the time until a fixed income secu-
rity provides its final payment, taking no account of the pattern of the
security's payments before maturity. In contrast, duration incorporates a
bond's yield, coupon interest payments, final maturity and call features into
one measure. Duration management is one of the fundamental tools used by the
Adviser.

Duration is a measure of the expected life of a fixed income security on a
present value basis. Duration takes the length of the time intervals between
the present time and the time that the interest and principal payments are
scheduled or, in the case of a callable bond, expected to be received, and
weights them by the present values of the cash to be received at each future
point in time. For any fixed income security with interest payments occurring
before the payment of principal, duration is always less than maturity. In
general, all other things being equal, the lower the stated or coupon rate of
interest of a fixed income security, the longer the duration of the security;
conversely, the higher the stated or coupon rate of interest of a fixed income
security, the shorter the duration of the security.

Futures, options and options on futures have durations which, in general,
are closely related to the duration of the securities which underlie them.
Holding long futures or call option positions (backed by a segregated account
of cash and cash equivalents) will lengthen a Portfolio's duration by approxi-
mately the same amount that holding an equivalent amount of the underlying se-
curities would.

Short futures or put option positions have durations roughly equal to the
negative duration of the securities that underlie these positions, and have
the effect of reducing portfolio duration by approximately the same amount
that selling an equivalent amount of the underlying securities would.

There are some situations where even the standard duration calculation does
not properly reflect the interest rate exposure of a security. For example,
floating and variable rate securities often have final maturities of ten or
more years; however, their interest rate exposure corresponds to the frequency
of the coupon reset. For inflation-indexed bonds, duration is calculated on
the basis of modified real duration, which measures price changes of infla-
tion-indexed bonds on the basis of changes in real, rather than nominal, in-
terest rates. Another example where the interest rate exposure is not properly
captured by duration is the case of mortgage pass-through securities. The
stated final maturity of such securities is generally 30 years, but current
prepayment rates are more critical in determining the securities' interest
rate exposure. Finally, the duration of a fixed income security may vary over
time in response to changes in interest rates and other market factors. In
these and other similar situations, the Adviser will use more sophisticated
analytical techniques that incorporate the anticipated economic life of a se-
curity into the determination of its interest rate exposure.

Prospectus A-1
<PAGE>

APPENDIX B

DESCRIPTION OF SECURITIES RATINGS

A Portfolio's investments may range in quality from securities rated in the
lowest category in which the Portfolio is permitted to invest to securities
rated in the highest category (as rated by Moody's or S&P or, if unrated, de-
termined by the Adviser to be of comparable quality). The percentage of a
Portfolio's assets invested in securities in a particular rating category will
vary. Following is a description of Moody's and S&P's ratings applicable to
fixed income securities.

Moody's Investors Service, Inc.

Corporate and Municipal Bond Ratings

Aaa: Bonds which are rated Aaa are judged to be of the best quality. They
carry the smallest degree of investment risk and are generally referred to as
"gilt edge." Interest payments are protected by a large or by an exceptionally
stable margin and principal is secure. While the various protective elements
are likely to change, such changes as can be visualized are most unlikely to
impair the fundamentally strong position of such issues.

Aa: Bonds which are rated Aa are judged to be of high quality by all stan-
dards. Together with the Aaa group they comprise what are generally known as
high-grade bonds. They are rated lower than the best bonds because margins of
protection may not be as large as in Aaa securities or fluctuation of protec-
tive elements may be of greater amplitude or there may be other elements pres-
ent that make the long-term risks appear somewhat larger than with Aaa securi-
ties.

A: Bonds which are rated A possess many favorable investment attributes and
are to be considered as upper-medium-grade obligations. Factors giving secu-
rity to principal and interest are considered adequate but elements may be
present that suggest a susceptibility to impairment sometime in the future.

Baa: Bonds which are rated Baa are considered as medium-grade obligations
(i.e., they are neither highly protected nor poorly secured). Interest pay-
ments and principal security appear adequate for the present but certain pro-
tective elements may be lacking or may be characteristically unreliable over
any great length of time. Such bonds lack outstanding investment characteris-
tics and in fact have speculative characteristics as well.

Ba: Bonds which are rated Ba are judged to have speculative elements; their
future cannot be considered as well-assured. Often the protection of interest
and principal payments may be very moderate and thereby not well safeguarded
during both good and bad times over the future. Uncertainty of position char-
acterizes bonds in this class.

B: Bonds which are rated B generally lack characteristics of a desirable in-
vestment. Assurance of interest and principal payments or of maintenance of
other terms of the contract over any long period of time may be small.

Caa: Bonds which are rated Caa are of poor standing. Such issues may be in
default or there may be present elements of danger with respect to principal
or interest.

Prospectus B-1
<PAGE>

Ca: Bonds which are rated Ca represent obligations which are speculative in
a high degree. Such issues are often in default or have other marked shortcom-
ings.

C: Bonds which are rated C are the lowest rated class of bonds and issues so
rated can be regarded as having extremely poor prospects of ever attaining any
real investment standing.

Moody's applies numerical modifiers, 1, 2, and 3 in each generic rating
classified from Aa through B in its corporate bond rating system. The modifier
1 indicates that the security ranks in the higher end of its generic rating
category; the modifier 2 indicates a mid-range ranking; and the modifier 3 in-
dicates that the issue ranks in the lower end of its generic rating category.

Corporate Short-Term Debt Ratings

Moody's short-term debt ratings are opinions of the ability of issuers to
repay punctually senior debt obligations which have an original maturity not
exceeding one year. Obligations relying upon support mechanisms such as let-
ters of credit and bonds of indemnity are excluded unless explicitly rated.

Moody's employs the following three designations, all judged to be invest-
ment grade, to indicate the relative repayment ability of rated issuers:

PRIME-1: Issuers rated Prime-1 (or supporting institutions) have a superior
ability for repayment of senior short-term debt obligations. Prime-1 repayment
ability will often be evidenced by many of the following characteristics:
leading market positions in well-established industries; high rates of return
on funds employed; conservative capitalization structure with moderate reli-
ance on debt and ample asset protection; broad margins in earnings coverage of
fixed financial charges and high internal cash generation; and well-estab-
lished access to a range of financial markets and assured sources of alternate
liquidity.

PRIME-2: Issuers rated Prime-2 (or supporting institutions) have a strong
ability for repayment of senior short-term debt obligations. This will nor-
mally be evidenced by many of the characteristics cited above but to a lesser
degree. Earnings trends and coverage ratios, while sound, may be more subject
to variation. Capitalization characteristics, while still appropriate, may be
more affected by external conditions. Ample alternate liquidity is maintained.

PRIME-3: Issuers rated Prime-3 (or supporting institutions) have an accept-
able ability for repayment of senior short-term obligations. The effect of in-
dustry characteristics and market compositions may be more pronounced. Vari-
ability in earnings and profitability may result in changes in the level of
debt protection measurements and may require relatively high financial lever-
age. Adequate alternate liquidity is maintained.

NOT PRIME: Issuers rated Not Prime do not fall within any of the Prime rat-
ing categories.

Standard & Poor's Ratings Services

Corporate and Municipal Bond Ratings

Investment Grade

AAA: Debt rated AAA has the highest rating assigned by Standard & Poor's.
Capacity to pay interest and repay principal is extremely strong.

B-2 PIMCO Variable Insurance Trust
<PAGE>

AA: Debt rated AA has a very strong capacity to pay interest and repay prin-
cipal and differs from the highest rated issues only in small degree.

A: Debt rated A has a strong capacity to pay interest and repay principal
although it is somewhat more susceptible to the adverse effects of changes in
circumstances and economic conditions than debt in higher rated categories.

BBB: Debt rated BBB is regarded as having an adequate capacity to pay inter-
est and repay principal. Whereas it normally exhibits adequate protection pa-
rameters, adverse economic conditions, or changing circumstances are more
likely to lead to a weakened capacity to pay interest and repay principal for
debt in this category than in higher-rated categories.

Speculative Grade

Debt rated BB, B, CCC, CC, and C is regarded as having predominantly specu-
lative characteristics with respect to capacity to pay interest and repay
principal. BB indicates the least degree of speculation and C the highest.
While such debt will likely have some quality and protective characteristics,
these are outweighed by large uncertainties or major exposures to adverse con-
ditions.

BB: Debt rated BB has less near-term vulnerability to default than other
speculative issues. However, it faces major ongoing uncertainties or exposure
to adverse business, financial, or economic conditions which could lead to in-
adequate capacity to meet timely interest and principal payments. The BB rat-
ing category also is used for debt subordinated to senior debt that is as-
signed an actual or implied BBB- rating.

B: Debt rated B has a greater vulnerability to default but currently has the
capacity to meet interest payments and principal repayments. Adverse business,
financial, or economic conditions will likely impair capacity or willingness
to pay interest and repay principal. The B rating category also is used for
debt subordinated to senior debt that is assigned an actual or implied BB or
BB- rating.

CCC: Debt rated CCC has a currently identifiable vulnerability to default
and is dependent upon favorable business, financial, and economic conditions
to meet timely payment of interest and repayment of principal. In the event of
adverse business, financial or economic conditions, it is not likely to have
the capacity to pay interest and repay principal. The CCC rating category also
is used for debt subordinated to senior debt that is assigned an actual or im-
plied B or B- rating.

CC: The rating CC is typically applied to debt subordinated to senior debt
that is assigned an actual or implied CCC rating.

C: The rating C is typically applied to debt subordinated to senior debt
that is assigned an actual or implied CCC- debt rating. The C rating may be
used to cover a situation where a bankruptcy petition has been filed, but debt
service payments are continued.

CI: The rating CI is reserved for income bonds on which no interest is being
paid.

D: Debt rated D is in payment default. The D rating category is used when
interest payments or principal payments are not made on the date due even if
the applicable grace period has not expired, unless S&P believes that such
payments will be made during such grace period. The D rating will also be used
upon the filing of a bankruptcy petition if debt service payments are jeopar-
dized.

Prospectus B-3
<PAGE>

Plus (+) or Minus (-): The ratings from AA to CCC may be modified by the ad-
dition of a plus or minus sign to show relative standing within the major rat-
ing categories.

Provisional ratings: The letter "p" indicates that the rating is provision-
al. A provisional rating assumes the successful completion of the project be-
ing financed by the debt being rated and indicates that payment of debt serv-
ice requirements is largely or entirely dependent upon the successful and
timely completion of the project. This rating, however, while addressing
credit quality after completion of the project, makes no comment on the like-
lihood of, or the risk of default upon failure of, such completion. The in-
vestor should exercise his own judgment with respect to such likelihood and
risk.

r: The "r" is attached to highlight derivative, hybrid, and certain other
obligations that S&P believes may experience high volatility or high variabil-
ity in expected returns due to non-credit risks. Examples of such obligations
are: securities whose principal or interest return is indexed to equities,
commodities, or currencies; certain swaps and options; and interest only and
principal only mortgage securities.

The absence of an "r" symbol should not be taken as an indication that an
obligation will exhibit no volatility or variability in total return.

N.R.: Not rated.

Debt obligations of issuers outside the United States and its territories
are rated on the same basis as domestic corporate and municipal issues. The
ratings measure the creditworthiness of the obligor but do not take into ac-
count currency exchange and related uncertainties.

Commercial Paper Rating Definitions

A Standard & Poor's commercial paper rating is a current assessment of the
likelihood of timely payment of debt having an original maturity of no more
than 365 days. Ratings are graded into several categories, ranging from A for
the highest quality obligations to D for the lowest. These categories are as
follows:

A-1: This highest category indicates that the degree of safety regarding
timely payment is strong. Those issues determined to possess extremely
strong safety characteristics are denoted with a plus sign (+) designation.

A-2: Capacity for timely payment on issues with this designation is
satisfactory. However, the relative degree of safety is not as high as for
issues designated A-1.

A-3: Issues carrying this designation have adequate capacity for timely
payment. They are, however, more vulnerable to the adverse effects of
changes in circumstances than obligations carrying the higher designations.

B: Issues rated B are regarded as having only speculative capacity for
timely payment.

C: This rating is assigned to short-term debt obligations with a doubtful
capacity for payment.

D: Debt rated D is in payment default. The D rating category is used when
interest payments or principal payments are not made on the date due, even
if the applicable grace period has not expired, unless S&P believes that
such payments will be made during such grace period.

A commercial paper rating is not a recommendation to purchase, sell or hold
a security inasmuch as it does not comment as to market price or suitability
for a particular investor. The ratings are based on current information fur-
nished to Standard & Poor's by the issuer or obtained from other sources it
considers reliable. Standard & Poor's does not perform an audit in connection
with any rating and may, on occasion, rely on unaudited financial information.
The ratings may be changed, suspended, or withdrawn as a result of changes in
or unavailability of such information.

B-4 PIMCO Variable Insurance Trust
<PAGE>

P I M C O

PIMCO
Variable
Insurance
Trust

For More Information

The following documents are available that offer further information on the
Portfolios of PIMCO Variable Insurance Trust.

Annual/Semi-Annual Reports to Shareholders The Trust's annual and semi-annual
reports include a discussion of the market conditions and investment strategies
that significantly affected the Portfolios' performance during its last fiscal
year or other period.

Statement of Additional Information (SAI) The SAI contains additional
information about the Portfolios. A current SAI has been filed with the
Securities and Exchange Commission, and is incorporated into this prospectus by
reference.

To request a free copy of these documents or to make inquiries about the
Portfolios, please write or call:

PIMCO Variable Insurance Trust
840 Newport Center Drive
Suite 300
Newport Beach, CA 92660

Telephone:
1-888-746-2688

Information about the Trust (including the SAI) can be reviewed and copied at
the Securities and Exchange Commission's Public Reference Room in
Washington, D.C. Information on the operation of the public reference room may
be obtained by calling the Commission at 1-800-SEC-0330. Reports and other
information about the Trust are available on the Commission's Internet site at
www.sec.gov, and copies of that information may be obtained, upon payment of a
duplicating fee, by writing the Public Reference Section of the Commission,
Washington, D.C. 20549-6009.

SEC File Number: 811-8399

Prospectus

- --------------------------------------------------------------------------------

December 1, 1999
<PAGE>

P I M C O

PIMCO
Variable
Insurance
Trust Intermediate Duration Bond Portfolios
Total Return Bond Portfolio
High Yield Bond Portfolio

Stock Portfolios
StocksPLUS Growth and Income Portfolio

Prospectus

- --------------------------------------------------------------------------------

December 1, 1999
<PAGE>

PIMCO Variable Insurance Trust

Prospectus

December 1, 1999

The PIMCO Total Return Bond, High Yield Bond and StocksPLUS Growth and Income
Portfolios (the "Portfolios"), which are series of PIMCO Variable Insurance
Trust (the "Trust"), are designed to provide access to the professional in-
vestment management services offered by Pacific Investment Management Company
("PIMCO" or the "Adviser"). Each Portfolio has its own investment objective
and strategies and its own risk/reward profile, which are described in this
Prospectus. The investments made by the Portfolios at any given time are not
expected to be the same as those made by other mutual funds for which PIMCO
acts as investment adviser, including mutual funds with investment objectives
and strategies similar to those of the Portfolios. Accordingly, the perfor-
mance of the Portfolios can be expected to vary from that of the other mutual
funds.

This Prospectus gives vital information you should know before investing in
the Portfolios. For your own benefit and protection, please read it before you
invest and keep it for future reference.

This Prospectus should be read in conjunction with the prospectus of the
Separate Account. Both prospectuses should be read carefully and retained for
future reference.

TABLE OF CONTENTS

<TABLE>
<S> <C>
OVERVIEW.................................................................... 3

DESCRIPTION OF PORTFOLIOS................................................... 5

PIMCO Total Return Bond Portfolio......................................... 5
PIMCO High Yield Bond Portfolio........................................... 7
PIMCO StocksPLUS Growth and Income Portfolio.............................. 9

MANAGEMENT OF THE TRUST..................................................... 11

Adviser and Administrator................................................. 11
Advisory and Administrative Fees.......................................... 12
Portfolio Transactions.................................................... 12

PURCHASE OF SHARES.......................................................... 13

REDEMPTION OF SHARES........................................................ 13

NET ASSET VALUE............................................................. 14

TAXES....................................................................... 14

RISK FACTORS AND SPECIAL CONSIDERATIONS..................................... 15

FINANCIAL HIGHLIGHTS........................................................ 20

OTHER INFORMATION........................................................... 21

Portfolio Names........................................................... 21
Total Return ............................................................. 21
Performance Information of Similar Funds.................................. 21

APPENDIX A.................................................................. A-1

APPENDIX B.................................................................. B-1
</TABLE>

Prospectus 2
<PAGE>

OVERVIEW

Portfolios at a Glance

<TABLE>
<CAPTION>
Intermediate Duration
Bond Portfolios Primary Investments Duration Credit Quality(1) Foreign(2)
- --------------------- ----------------------------------------- --------- ----------------- ----------
<S> <C> <C> <C> <C>
Total Return Bond Intermediate maturity fixed income 3-6 years B to Aaa; max 10% 0-20%
securities below Baa
High Yield Bond Higher yielding fixed income securities 2-6 years B to Aaa; min 65% 0%
below Baa
Stock Portfolios
- ----------------
StocksPLUS Growth and S&P 500 stock index derivatives backed 0-1 year B to Aaa; max 10% 0-20%
Income by a portfolio of short-term fixed income below Baa
securities
</TABLE>
- --------
(1) As rated by Moody's Investors Service, Inc., or if unrated, determined to be
of comparable quality. For specific information concerning the credit
quality of the securities held by each Portfolio, see that Portfolio's
description of Main Investment Strategies.

(2) Percentage limitations relate to foreign currency-denominated securities.
Each Portfolio may invest beyond these limits in U.S. dollar-denominated
securities of foreign issuers.

Investment Strategies and Risk Factors

Risk Factors. The major risks associated with investing in each Portfolio are
described under the heading "Risk Factors" in the Description of Portfolios.
Please be sure to read all risk disclosures carefully before investing. This
Prospectus does not describe all of the risks of every security or technique
that the Portfolios may use. For such information, please refer to the Statement
of Additional Information.

Fixed Income Instruments

"Fixed Income Instruments" as used in this Prospectus means:

. securities issued or guaranteed by the U.S. Government, its agencies or
instrumentalities ("U.S. Government securities");

. corporate debt securities, including convertible securities and corporate
commercial paper;

. mortgage-backed and other asset-backed securities;

. inflation-indexed bonds issued both by governments and corporations;

. structured notes, including hybrid or "indexed" securities, catastrophe
bonds and loan participations;

. delayed funding loans and revolving credit facilities;

. bank certificates of deposit, fixed time deposits and bankers'
acceptances;

. repurchase agreements and reverse repurchase agreements;

. obligations of foreign governments or their subdivisions, agencies and
instrumentalities; and

. obligations of international agencies or supranational entities.

3 PIMCO Variable Insurance Trust
<PAGE>

OVERVIEW (continued)

Fixed Income Instruments (continued)

Fixed Income Instruments may have fixed, variable, or floating rates of in-
terest, including rates of interest that vary inversely at a multiple of a des-
ignated or floating rate, or that vary according to changes in relative values
of currencies. Each of the Portfolios may hold different percentages of its as-
sets in these various types of securities.

Ratings of Debt Securities

Investment Grade Debt Securities are those receiving ratings from at least
one NRSRO in one of the four highest rating categories or, if unrated by any
NRSRO, deemed comparable by PIMCO.

Prospectus 4
<PAGE>

DESCRIPTION OF PORTFOLIOS

PIMCO TOTAL RETURN BOND PORTFOLIO

Investment Objective

The Total Return Bond Portfolio seeks to maximize total return, consistent
with preservation of capital and prudent investment management.

Main Investment Strategies

Risk Factors

An investment in the Portfolio is not a deposit of a bank and is not insured
or guaranteed by the Federal Deposit Insurance Corporation or any other govern-
ment agency.

Performance

[PERFORMANCE CHART APPEARS HERE]

1998
----------
8.61%

Year to date total return through 3/31/99: -0.85%
Best quarter: Q3 '98 5.43%; Worst quarter: Q1 '99 -0.85%

5 PIMCO Variable Insurance Trust
<PAGE>

- --------------------------------------------------------------------------------
Average Annual Total Returns
for the year ended December 31, 1998

<TABLE>
<CAPTION>
1 Year 5 Years 10 Years
<S> <C> <C> <C>
Total Return Bond 8.61% N/A N/A
Lehman Brothers Aggregate Bond Index 8.69% N/A N/A
</TABLE>

Fees and Expenses

The table below describes the fees and expenses (as a percentage of net as-
sets) that you may pay in connection with an investment in the Total Return
Bond Portfolio.

- --------------------------------------------------------------------------------
Annual Portfolio Operating Expenses
(expenses deducted from Portfolio assets)

- --------------------------------------------------------------------------------
Example

This example is intended to help you compare the cost of investing in the
Portfolio with the cost of investing in other portfolios. The example assumes:

. A $10,000 investment for the time periods shown;

. Redemption at the end of each period;

. A hypothetical 5% annual return; and

. Portfolio operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions
your costs would be:

<TABLE>
<CAPTION>
1 Year 3 Years 5 Years 10 Years
<S> <C> <C> <C>
$ 66 $ 208 $ 362 $ 810
</TABLE>

Prospectus 6
<PAGE>

PIMCO HIGH YIELD BOND PORTFOLIO

Investment Objective

The High Yield Bond Portfolio seeks to maximize total return, consistent
with preservation of capital and prudent investment management.

Main Investment Strategies

The Portfolio may invest all of its assets in derivative instruments, such
as options, futures contracts or swap agreements, or in mortgage- or asset-
backed securities. The Portfolio may lend its portfolio securities to brokers,
dealers and other financial institutions to earn income. The Portfolio may en-
ter into a series of purchase and sale contracts or use other investment tech-
niques to obtain market exposure to the securities in which it primarily in-
vests.

Risk Factors

An investment in the Portfolio is not a deposit of a bank and is not insured
or guaranteed by the Federal Deposit Insurance Corporation or any other gov-
ernment agency.

Performance

Performance information for this Portfolio is not provided because it has
not been in operation for a full calendar year.

Fees and Expenses

The table below describes the fees and expenses (as a percentage of net as-
sets) that you may pay in connection with an investment in the High Yield Bond
Portfolio.

- -------------------------------------------------------------------------------
Annual Portfolio Operating Expenses
(expenses deducted from Portfolio assets)

* PIMCO has agreed to reduce its administrative fee, subject to potential fu-
ture reimbursement, to the extent that total Portfolio operating expenses
would exceed, due to organizational expenses and the payment by the Portfolio
of its pro rata portion of the Trust's Trustees' fees, 0.75% of average daily
net assets.

- -------------------------------------------------------------------------------

7 PIMCO Variable Insurance Trust
<PAGE>

- --------------------------------------------------------------------------------
Example: Expenses on a $ 10,000 Investment

This example is intended to help you compare the cost of investing in the
Portfolio with the cost of investing in other portfolios. The example assumes:

. A $10,000 investment for the time periods shown;

. Redemption at the end of each period;

. A hypothetical 5% annual return; and

. Portfolio operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions
your costs would be:

<TABLE>
<CAPTION>
1 Year 3 Years 5 Years 10 Years
<S> <C> <C> <C>
$ 77 $ 240 $ 417 $ 930
</TABLE>
Prospectus 8
<PAGE>

PIMCO STOCKSPLUS GROWTH AND INCOME PORTFOLIO

Investment Objective

The StocksPLUS Growth and Income Portfolio seeks to achieve a total return
which exceeds the total return performance of the S&P 500.

Main Investment Strategies

The StocksPLUS Growth and Income Portfolio invests in common stocks, op-
tions, futures, options on futures and swaps. Under normal market conditions,
the Portfolio invests substantially all of its assets in S&P 500 derivatives,
backed by a portfolio of Fixed Income Instruments. The Portfolio uses S&P 500
derivatives in addition to or in place of S&P 500 stocks to attempt to equal
or exceed the performance of the S&P 500. The Adviser actively manages the
fixed income assets held by the Portfolio, with a view to enhancing the Port-
folio's total return investment performance, subject to an overall portfolio
duration which is normally not expected to exceed one year. See "Appendix A--
Description of Duration."

The S&P 500 is composed of 500 selected common stocks that represent approx-
imately two-thirds of the total market value of all U.S. common stocks. The
Portfolio is neither sponsored by nor affiliated with S&P. The Portfolio will
seek to remain invested in S&P 500 derivatives or S&P 500 stocks even when the
S&P 500 is declining.

When S&P 500 derivatives appear to be overvalued relative to the S&P 500,
the Portfolio may invest up to 100% of its assets in a "basket" of S&P 500
stocks. The composition of this basket will be determined by standard statis-
tical techniques that analyze the historical correlation between the return of
every stock currently in the S&P 500 and the return on the S&P 500 itself. The
Adviser may employ fundamental stock analysis only to choose among stocks that
have already satisfied the statistical correlation tests. Stocks chosen for
the Portfolio are not limited to those with any particular weighting in the
S&P 500.

Assets not invested in equity securities may be invested in Fixed Income In-
struments. The Portfolio may invest up to 10% of its assets in high yield
bonds rated B or higher by Moody's or S&P, or, if unrated, determined by the
Adviser to be of comparable quality. In addition, the Portfolio may lend its
portfolio securities to brokers, dealers and other financial institutions to
earn income. The Portfolio may invest up to 20% of its assets in securities of
foreign issuers, may purchase and sell options and futures on foreign curren-
cies, and may enter into forward currency contracts. The Portfolio may invest
all of its assets in derivative instruments, such as options, futures con-
tracts or swap agreements.

Risk Factors

An investment in the StocksPLUS Growth and Income Portfolio is subject to
investment risk, including possible loss of the principal amount invested. The
Portfolio is subject to market risk, which is the risk that the market value
of securities may move up and down, sometimes rapidly and unpredictably. The
Portfolio also is subject to interest rate risk. Generally, the value of fixed
income securities will change inversely with changes in interest rates. As in-
terest rates rise, market value tends to decrease. This risk will be greater
for long-term securities than for short-term securities. Derivative instru-
ments may be particularly sensitive to changes in prevailing interest rates.
Unexpected changes in interest rates may adversely affect the value of the
Portfolio's investments in particular derivative instruments.

To the extent that the Fund invests in S&P 500 derivatives backed by a port-
folio of Fixed Income Instruments, under certain conditions, generally in a
market where the value of both S&P 500 derivatives and Fixed Income Instru-
ments are declining, the Fund may experience greater losses than would be the
case if it were to invest directly in a portfolio of S&P 500 stocks.

A large number of investors use S&P 500 derivatives for both hedging and
speculative purposes, and although generally this helps guarantee a liquid
market in those instruments, at times liquidity may be limited.

9 PIMCO Variable Insurance Trust
<PAGE>

From time to time, requirements of the Internal Revenue Code or an unantici-
pated inability to close out positions when it would be most advantageous to do
so may limit the Adviser's ability to use S&P 500 derivatives.

The Portfolio also is subject to credit risk, which is the possibility that
an issuer of a security, or a counterparty to a derivative contract, will
default or become unable to meet a financial obligation. High yield bonds carry
a high degree of credit risk. Securities of foreign issuers may be subject to
additional risk factors, including foreign currency exchange rate fluctuations,
adverse regulatory conditions, foreign taxes, or political or economic
uncertainty. For a further explanation, see "Risk Factors and Special
Considerations," which you should read carefully before investing.

An investment in the Portfolio is not a deposit of a bank and is not insured
or guaranteed by the Federal Deposit Insurance Corporation or any other govern-
ment agency.

Performance

The bar chart below shows the actual performance of the Portfolio from incep-
tion. It provides some indication of the variability of the Portfolio's returns
from year to year. The table below shows how the Portfolio's average annual re-
turns for the period indicated compare to those of the Portfolio's benchmark,
the S&P 500 Index. This is a widely recognized, unmanaged market index gener-
ally considered representative of the stock market as a whole. The bar chart
and table do not reflect Variable Contract fees and expenses. If they did, per-
formance would have been lower. The Portfolio's past performance does not nec-
essarily indicate how the Portfolio will perform in the future.

[PERFORMANCE CHART APPEARS HERE]

1998
----------
30.11%

Year to date total return through 3/31/99: 4.07%
Best quarter: Q4 '98 21.95%; Worst quarter: Q3 '98 -8.82%

- --------------------------------------------------------------------------------
Average Annual Total Returns
for the year ended December 31, 1998

<TABLE>
<CAPTION>
1 Year 5 Years 10 Years
<S> <C> <C> <C>
StocksPLUS Growth and Income 30.11% N/A N/A
S&P 500 Index 28.58% N/A N/A
</TABLE>

Fees and Expenses

The table below describes the fees and expenses (as a percentage of net as-
sets) that you may pay in connection with an investment in the StocksPLUS
Growth and Income Portfolio.

- --------------------------------------------------------------------------------
Annual Portfolio Operating Expenses
(expenses deducted from Portfolio assets)

<TABLE>
<S> <C>
Advisory Fee 0.40 %
Administrative Fee 0.25 %
Other Expenses 0.07 %
-------
Total Portfolio Operating Expenses 0.72 %
Expense Reduction* (0.07)%
------
Net Portfolio Operating Expenses 0.65 %
</TABLE>

- --------------------------------------------------------------------------------
Example

This example is intended to help you compare the cost of investing in the
Portfolio with the cost of investing in other portfolios. The example assumes:

. A $10,000 investment for the time periods shown;

. Redemption at the end of each period;

. A hypothetical 5% annual return; and

. Portfolio operating expenses remain the same.

Although your actual costs may be higher or lower, based on these assumptions
your costs would be:

<TABLE>
<CAPTION>
1 Year 3 Years 5 Years 10 Years
<S> <C> <C> <C>
$ 66 $ 208 $ 362 $ 810
</TABLE>

Prospectus 10
<PAGE>

MANAGEMENT OF THE TRUST

Adviser and Administrator

The table below provides information about the individual portfolio managers
responsible for management of the Trust's Portfolios, including their occupa-
tions for the past five years.

<TABLE>
<CAPTION>
Portfolio Manager And Business
Portfolio Experience (Past Five Years)
- --------- ------------------------------
<C> <S>
Total Return Bond Portfolio William H. Gross, Managing Director,
StocksPLUS Growth and Income Portfolio PIMCO. A Fixed Income Portfolio
Manager, Mr. Gross is one of the
founders of PIMCO and has managed the
PIMCO Total Return Fund for the PIMCO
Funds: Pacific Investment Management
Series since its inception on May 11,
1987. Mr. Gross is the leader of a
team which has managed the PIMCO
StocksPLUS Fund for the PIMCO Funds:
Pacific Investment Management Series
since January 6, 1998.

High Yield Bond Portfolio Benjamin Trosky, Managing Director,
PIMCO. A Fixed Income Portfolio
Manager, Mr. Trosky joined PIMCO in
1990 and has managed the PIMCO High
Yield Fund for the PIMCO Funds: Pacific
Investment Management Series since its
inception on December 16, 1992.
</TABLE>

11 PIMCO Variable Insurance Trust
<PAGE>

including the provision of support services such as providing information
about the Trust and the Portfolios, the delivery of Trust documents, and other
services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO
does not receive any separate fees for such expenses.

Advisory and Administrative Fees

<TABLE>
<CAPTION>
Advisory Fee
Portfolio Rate
--------- ------------
<S> <C>
Total Return Bond and StocksPLUS Growth and
Income Portfolios......................................... 0.40%
High Yield Bond Portfolio.................................. 0.50%
</TABLE>

Portfolio Transactions

Prospectus 12
<PAGE>

PURCHASE OF SHARES

While the Portfolios currently do not foresee any disadvantages to Variable
Contract Owners if the Portfolios serve as an investment medium for both vari-
able annuity contracts and variable life insurance policies, due to differ-
ences in tax treatment or other considerations, it is theoretically possible
that the interest of owners of annuity contracts and insurance policies for
which the Portfolios served as an investment medium might at some time be in
conflict. However, the Trust's Board of Trustees and each insurance company
with a separate account allocating assets to the Portfolios are required to
monitor events to identify any material conflicts between variable annuity
contract owners and variable life insurance policy owners, and would have to
determine what action, if any, should be taken in the event of such a con-
flict. If such a conflict occurred, an insurance company participating in the
Portfolios might be required to redeem the investment of one or more of its
separate accounts from the Portfolios, which might force the Portfolios to
sell securities at disadvantageous prices.

The Trust is "open for business" on each day the New York Stock Exchange
(the "Exchange") is open for trading. A purchase order, together with payment
in proper form, received before the close of regular trading on the Exchange
(normally 4:00 p.m., Eastern time) on a day the Trust is open for business
will be effected at that day's net asset value. In order to facilitate effi-
cient operation of the StocksPLUS Growth and Income Portfolio, the Trust re-
quests that all purchase orders for this Portfolio be received at least one
hour prior to the close of regular trading on the Exchange (normally 3:00
p.m., Eastern time). An order received after the close of regular trading on
the Exchange generally will be effected at the net asset value determined on
the next business day.

REDEMPTION OF SHARES

13 PIMCO Variable Insurance Trust
<PAGE>

NET ASSET VALUE

In determining their daily net asset values, the Portfolios use price data
received shortly after 4:00 p.m. Eastern time believed to reflect the current
market value of securities held by the Portfolios as of the closing of the Ex-
change. The Portfolios intend to use these prices regardless of the impact of
any post-closing adjustments to securities prices, as long as, in the view of
the Portfolios, such prices represent the current market value of the securi-
ties as of the time selected by the Portfolios for the calculation of net as-
set value. Portfolios that invest in securities traded in foreign securities
markets may trade such securities on days when the Exchange is not open, and
the net asset value per share of these Portfolios may be affected signifi-
cantly on days when investors do not have access to the Portfolios.

TAXES

Prospectus 14
<PAGE>

RISK FACTORS AND SPECIAL CONSIDERATIONS

The Portfolios are permitted to use, within limits established by the Trust-
ees and imposed by applicable laws, a wide variety of securities and invest-
ment practices, each of which has certain risks and opportunities associated
with it. To the extent that a Portfolio uses these securities or practices,
its overall performance may be affected, either positively or negatively. The
following pages describe certain of the securities in which the Portfolios may
invest and certain of investment practices in which the Portfolios may engage,
along with the risks associated with them. Additional information about these
and other investments and investment practices may be found in the Statement
of Additional Information, which you may obtain free of charge by calling
(888) 746-2688.

U.S. Government Securities

Corporate Debt Securities

Convertible Securities and Equity Securities

Although the Total Return Bond and High Yield Bond Portfolios intend to in-
vest primarily in fixed income securities, each may invest in convertible se-
curities or equity securities. While some countries or companies may be re-
garded as favorable investments, pure fixed income opportunities may be unat-
tractive or limited due to insufficient supply, or legal or technical restric-
tions. In such cases, a Portfolio may consider equity securities or convert-
ible securities to gain exposure to such investments.

15 PIMCO Variable Insurance Trust
<PAGE>

Variable and Floating Rate Securities

Variable and floating rate securities provide for a periodic adjustment in
the interest rate paid on the obligations. The Total Return Bond and High
Yield Bond Portfolios may invest in floating rate debt instruments ("float-
ers") and engage in credit spread trades. The interest rate on a floater is a
variable rate which is tied to another interest rate, such as a money-market
index or Treasury bill rate, and resets periodically. While variable and
floating rate securities provide a Portfolio with a certain degree of protec-
tion against rises in interest rates, a Portfolio will participate in any de-
clines in interest rates as well.

Inflation-Indexed Bonds

Mortgage-Related and Other Asset-Backed Securities

Prospectus 16
<PAGE>

Foreign Securities

The Total Return Bond and High Yield Bond Portfolios may invest directly in
fixed income securities of non-U.S. issuers. The High Yield Bond Portfolio may
only invest in U.S. dollar-denominated fixed income securities of non-U.S. is-
suers. The StocksPLUS Growth and Income Portfolio may invest directly in for-
eign equity securities.

Investing in the securities of issuers in any foreign country involves spe-
cial risks and considerations not typically associated with investing in U.S.
companies. These risks include: differences in accounting, auditing and finan-
cial reporting standards; generally higher commission rates on foreign portfo-
lio transactions; the possibility of nationalization, expropriation or confis-
catory taxation; adverse changes in investment or exchange control regulations
(which may include suspension of the ability to transfer currency from a coun-
try); and political instability which could affect U.S. investments in foreign
countries. Additionally, foreign securities and dividends and interest payable
on those securities may be subject to foreign taxes, including taxes withheld
from payments on those securities. Foreign securities often trade with less
frequency and volume than domestic securities and therefore may exhibit
greater price volatility. Additional costs associated with an investment in
foreign securities may include higher custodial fees than apply to domestic
custodial arrangements and transaction costs of foreign currency conversions.
Changes in foreign exchange rates also will affect the value of securities de-
nominated or quoted in currencies other than the U.S. dollar.

The Total Return Bond and StocksPLUS Growth and Income Portfolios may invest
in the securities of issuers based in countries with developing economies. In-
vesting in developing (or "emerging market") countries involves certain risks
not typically associated with investing in U.S. securities, and imposes risks
greater than, or in addition to, risks of investing in foreign, developed
countries. These risks are detailed in the Statement of Additional Informa-
tion.

Foreign Currency Transactions

Foreign currency exchange rates may fluctuate significantly over short peri-
ods of time. The Total Return Bond and StocksPLUS Growth and Income Portfolios
may buy and sell foreign currencies on a spot and forward basis to reduce the
risks of adverse changes in foreign exchange rates. A forward foreign currency
exchange contract reduces a Portfolio's exposure to changes in the value of
the currency it will deliver and increases its exposure to changes in the
value of the currency it will exchange into. Contracts to sell foreign cur-
rency would limit any potential gain which might be realized by a Portfolio if
the value of the hedged currency increases. A Portfolio may enter into these
contracts for the purpose of hedging against foreign exchange risk arising
from the Portfolio's investment or anticipated investment in securities denom-
inated in foreign currencies. A Portfolio also may enter into these contracts
for purposes of increasing exposure to a foreign currency or to shift exposure
to foreign currency fluctuations from one country to another.

The Total Return Bond and StocksPLUS Growth and Income Portfolios may invest
in options on foreign currencies and foreign currency futures and options
thereon. The Portfolios also may invest in foreign currency exchange-related
securities, such as foreign currency warrants and other instruments whose re-
turn is linked to foreign currency exchange rates. These Portfolios will use
these techniques to hedge at least 75% of their exposure to foreign currency.
For a description of these instruments, see "Derivative Instruments" below and
the Statement of Additional Information.

17 PIMCO Variable Insurance Trust
<PAGE>

High Yield Securities ("Junk Bonds")

Derivative Instruments

Prospectus 18
<PAGE>

Catastrophe Bonds

Each of the Portfolios may invest in "catastrophe bonds." Catastrophe bonds
are fixed income securities, for which the return of principal and payment of
interest is contingent on the non-occurrence of a specific "trigger" event,
such as a hurricane or an earthquake. If a trigger event causes losses exceed-
ing a specific amount in the geographic region and time period specified in a
bond, a Portfolio investing in the bond may lose a portion or all of its prin-
cipal invested in the bond. If no trigger event occurs, the Portfolio will re-
cover its principal plus interest. Catastrophe bonds may also expose the Port-
folio to certain unanticipated risks including but not limited to issuer
(credit) default, adverse regulatory or jurisdictional interpretation, and ad-
verse tax consequences.

Temporary Defensive Positions

Illiquid Securities

Year 2000 Readiness Disclosure

19 PIMCO Variable Insurance Trust
<PAGE>

FINANCIAL HIGHLIGHTS

<TABLE>
<CAPTION>
Total Return High Yield
Selected Per Share Data for the Period Bond Bond StocksPLUS Growth
Ended: December 31, 1998 Portfolio(a) Portfolio(b) and Income Portfolio(c)
------------ ------------ -----------------------
<S> <C> <C> <C>
Net asset value, beginning of period.... $10.00 $10.00 $10.00
Income from Investment Operations
Net investment income(d)................ 0.56 0.51 0.30
Net gains or losses on securities (both
realized and unrealized)(d)............ 0.28 (0.34) 2.68
Total from investment operations........ 0.84 0.17 2.98
Less Distributions
Dividends (from net investment income).. (0.56) (0.50) (0.29)
Distributions (from capital gains)...... (0.19) 0.00 (0.11)
Total distributions..................... (0.75) (0.50) (0.40)
Net asset value, end of period.......... $10.09 $9.67 $12.58
Total return (%)........................ 8.61% 1.80% 30.11%
Ratios/Supplemental Data
Net assets, end of period (000's)....... $3,259 $49,761 $58,264
Ratio of expenses to average net
assets (%)(e).......................... 0.65% 0.75%* 0.65%
Ratio of net investment income to
average net assets (%)(e).............. 5.55% 7.90%* 5.30%
Portfolio turnover rate (%)............. 138.72% 12.94% 60.64%
</TABLE>

*Annualized

(a) Commenced operations on December 31, 1997.

(b) Commenced operations on April 30, 1998.

(d) Per share amounts based on average number of shares outstanding during the
period.

(e) Prior to the waiver and reimbursement of expenses, the ratios of expenses
to average net assets were 0.75%, 0.81% and 0.72% and the ratios of net
investment income to average net assets were 5.45%, 7.84% and 5.23% for
the Total Return Bond, High Yield Bond and StocksPLUS Growth and Income
Portfolios, respectively.

Prospectus 20
<PAGE>

OTHER INFORMATION

Portfolio Names

The Total Return Bond and High Yield Bond Portfolios consider the various
types of debt or fixed income securities in which each invests, as specifi-
cally described in this Prospectus, to be "bonds" as referenced in that Port-
folio's name. The use of this name is not meant to restrict a Portfolio's in-
vestment to the narrow category of debt securities that are formally called
"bonds."

Total Return

The "total return" sought by the Portfolios will consist of interest and
dividends from underlying securities, capital appreciation reflected in
unrealized increases in value of portfolio securities, or realized from the
purchase and sale of securities and use of futures and options, or gains from
favorable changes in foreign currency exchange rates. Generally, over the long
term, the total return obtained by a portfolio investing primarily in fixed
income securities is not expected to be as great as that obtained by a portfo-
lio that invests primarily in equity securities. At the same time, the market
risk and price volatility of a fixed income portfolio is expected to be less
than that of an equity portfolio, so that a fixed income portfolio is gener-
ally considered to be a more conservative investment. The change in market
value of fixed income securities (and therefore their capital appreciation or
depreciation) is largely a function of changes in the current level of inter-
est rates. Generally, when interest rates are falling, a portfolio with a
shorter duration will not generate as high a level of total return as a port-
folio with a longer duration. See "Appendix A--Description of Duration." Con-
versely, when interest rates are rising, a portfolio with a shorter duration
will generally outperform longer duration portfolios. When interest rates are
flat, shorter duration portfolios generally will not generate as high a level
of total return as longer duration portfolios (assuming that long-term inter-
est rates are higher than short-term rates, which is commonly the case). With
respect to the composition of any fixed income portfolio, the longer the dura-
tion of the portfolio, the greater the anticipated potential for total return,
with, however, greater attendant market risk and price volatility than for a
portfolio with a shorter duration. The market value of fixed income securities
denominated in currencies other than the U.S. dollar also may be affected by
movements in foreign currency exchange rates.

Performance Information of Similar Funds

The following table provides information concerning the historical total re-
turn performance of the Institutional Class shares of certain series of PIMCO
Funds: Pacific Investment Management Series ("PIMS"). Each PIMS series has in-
vestment objectives, policies and strategies substantially similar to those of
its respective Portfolio and is currently managed by the same portfolio manag-
er. While the investment objectives and policies of each PIMS series and its
respective Portfolio are similar, they are not identical and the performance
of the PIMS series and the Portfolio will vary. The data is provided to illus-
trate the past performance of the Adviser in managing a substantially similar
investment portfolio and does not represent the past performance of any of the
Portfolios or the future performance of any Portfolio or its portfolio manag-
er. Consequently, potential investors should not consider this performance
data as an indication of the future performance of any Portfolio or of its
portfolio manager.

21 PIMCO Variable Insurance Trust
<PAGE>

The performance data shown below reflects the operating expenses of each
PIMS series, which for all series except the StocksPLUS Fund are lower than
the expenses of the corresponding Portfolio. Performance would have been lower
for those series if the Portfolios' expenses were used. In addition, the PIMS
series, unlike the Portfolios, are not sold to Separate Accounts to fund Vari-
able Contracts. As a result, the performance results presented below do not
take into account charges or deductions against a Separate Account or Variable
Contract for cost of insurance charges, premium loads, administrative fees,
maintenance fees, premium taxes, mortality and expense risk charges, or other
charges that may be incurred under a Variable Contract for which the Portfolio
serves as an underlying investment vehicle. By contrast, Variable Contract
Owners with contract value allocated to the Portfolios will be subject to
charges and expenses relating to the Variable Contracts and Separate Accounts.

The PIMS series' performance data shown below is calculated in accordance
with standards prescribed by the SEC for the calculation of average annual to-
tal return information. The investment results of the PIMS series presented
below are unaudited and are not intended to predict or suggest results that
might be experienced by the PIMS series or the Portfolios. Share prices and
investment returns will fluctuate reflecting market conditions, as well as
changes in company-specific fundamentals of portfolio securities. The perfor-
mance data for the benchmark indices identified below does not reflect the
fees or expenses of the PIMS series or the Portfolios.

Average Annual Total Return for Similar Series of PIMS
and for Benchmark Indices for Periods Ended December 31, 1998

<TABLE>
<CAPTION>
1 3 5 Since Inception
PIMS Series Fund / Benchmark Index Year Years Years Inception Date
- ---------------------------------- ----- ----- ----- --------- ---------
<S> <C> <C> <C> <C> <C>
PIMCO Total Return Fund.................. 9.77 8.18 7.89 9.89 5/11/87
Lehman Aggregate Bond/1/ ............... 8.69 7.29 7.27

PIMCO High Yield Fund.................... 6.54 10.44 10.73 11.97 12/16/92
Lehman BB Int. Corporate/2/............. 5.74 8.77 9.09

PIMCO StocksPLUS Fund.................... 28.32 28.02 24.85 23.61 5/14/93
S & P 500/3/............................ 28.58 28.23 24.06
</TABLE>
- --------
/1/ The Lehman Brothers Aggregate Bond Index consists of the Lehman Brothers
Government/Corporate Bond Index, the Lehman Brothers Mortgage-Backed
Securities Index, and the Lehman Brothers Asset-Backed Securities Index.
The Government/Corporate Bond Index consists of the Lehman Brothers
Government Bond Index and the Lehman Brothers Corporate Bond Index. The
Government Bond Index includes all public obligations of the U.S. Treasury
(excluding flower bonds and foreign-targeted issues), its agencies and
quasi-federal corporations, and corporate debt guaranteed by the U.S.
Government. The Corporate Bond Index includes all publicly issued, fixed
rate, non-convertible investment grade U.S. dollar denominated corporate
debt registered with the SEC; it also includes debt issued or guaranteed
by foreign sovereign governments, municipalities, and governmental or
international agencies. The Mortgage-Backed Securities Index consists of
15- and 30-year fixed rate securities backed by mortgage pools of the
Government National Mortgage Association, the Federal Home Loan Mortgage
Corporation and the Federal National Mortgage Association (excluding
buydowns, manufactured homes and graduated equity mortgages). The Asset-
Backed Securities Index consists of credit card, auto and home equity
loans (excluding subordinated tranches) with an average life of one year.
Each Index includes income and distributions but does not reflect fees,
brokerage commissions or other expenses of investing.

/3/ The Standard & Poor's 500 Composite Stock Price Index is an unmanaged index
containing common stocks of 500 industrial, transportation, utility and
financial companies, regarded as generally representative of the U.S. stock
market. The Index reflects income and distributions, if any, but does not
reflect fees, brokerage commissions, or other expenses of investing.

Prospectus 22
<PAGE>

APPENDIX A

DESCRIPTION OF DURATION

Prospectus A-1
<PAGE>

APPENDIX B

DESCRIPTION OF SECURITIES RATINGS

Moody's Investors Service, Inc.

Corporate and Municipal Bond Ratings

Caa: Bonds which are rated Caa are of poor standing. Such issues may be in
default or there may be present elements of danger with respect to principal
or interest.

Prospectus B-1
<PAGE>

Ca: Bonds which are rated Ca represent obligations which are speculative in
a high degree. Such issues are often in default or have other marked shortcom-
ings.

C: Bonds which are rated C are the lowest rated class of bonds and issues so
rated can be regarded as having extremely poor prospects of ever attaining any
real investment standing.

Corporate Short-Term Debt Ratings

Moody's employs the following three designations, all judged to be invest-
ment grade, to indicate the relative repayment ability of rated issuers:

NOT PRIME: Issuers rated Not Prime do not fall within any of the Prime rat-
ing categories.

Standard & Poor's Ratings Services

Corporate and Municipal Bond Ratings

Investment Grade

AAA: Debt rated AAA has the highest rating assigned by Standard & Poor's.
Capacity to pay interest and repay principal is extremely strong.

B-2 PIMCO Variable Insurance Trust
<PAGE>

AA: Debt rated AA has a very strong capacity to pay interest and repay prin-
cipal and differs from the highest rated issues only in small degree.

Speculative Grade

CC: The rating CC is typically applied to debt subordinated to senior debt
that is assigned an actual or implied CCC rating.

CI: The rating CI is reserved for income bonds on which no interest is being
paid.

Prospectus B-3
<PAGE>

Plus (+) or Minus (-): The ratings from AA to CCC may be modified by the ad-
dition of a plus or minus sign to show relative standing within the major rat-
ing categories.

The absence of an "r" symbol should not be taken as an indication that an
obligation will exhibit no volatility or variability in total return.

N.R.: Not rated.

Commercial Paper Rating Definitions

A-2: Capacity for timely payment on issues with this designation is
satisfactory. However, the relative degree of safety is not as high as for
issues designated A-1.

B: Issues rated B are regarded as having only speculative capacity for
timely payment.

C: This rating is assigned to short-term debt obligations with a doubtful
capacity for payment.

B-4 PIMCO Variable Insurance Trust
<PAGE>

P I M C O

PIMCO
Variable
Insurance
Trust

For More Information

The following documents are available that offer further information on the
Portfolios of PIMCO Variable Insurance Trust.

To request a free copy of these documents or to make inquiries about the
Portfolios, please write or call:

PIMCO Variable Insurance Trust
840 Newport Center Drive
Suite 300
Newport Beach, CA 92660

Telephone:
1-888-746-2688

SEC File Number: 811-8399

Prospectus

- --------------------------------------------------------------------------------

December 1, 1999