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Filing Pursuant to Rule 424(b)(2)
Registration Statement No. 333-87185
PROSPECTUS SUPPLEMENT NO. 4
(TO PROSPECTUS DATED OCTOBER 8, 1999)
SHARES
AVIRON
COMMON STOCK
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You should read this prospectus supplement and the accompanying prospectus
carefully before you invest. Both documents contain information you should
consider carefully before making your investment decision.
INVESTING IN OUR COMMON STOCK INVOLVES CERTAIN RISKS. SEE "RISK FACTORS"
BEGINNING ON PAGE 6.
PLAN OF DISTRIBUTION
We are offering 309,995 shares of our common stock to Ridgeway Investment
Limited pursuant to this prospectus supplement. The common stock will be
purchased at a negotiated purchase price of $19.35515 per share. We will not pay
any other compensation in conjunction with the sale of our common stock.
Ridgeway and its pledgees, donees, transferees and other subsequent owners,
may offer their shares at various times in one or more of the following
transactions:
- in the over-the-counter market; or
- in privately negotiated transactions
at prevailing market prices at the time of sale, at prices related to those
prevailing market prices, at negotiated or at fixed prices.
The transactions in the shares may be effected by one or more of the
following methods:
- ordinary brokerage transactions and transactions in which the broker
solicits purchasers;
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- purchases by a broker or dealer as principal, and the resale by that
broker or dealer for its account under this prospectus, including
resale to another broker or dealer;
- block trades in which the broker or dealer will attempt to sell the
shares as agent but may position and resell a portion of the block as
principal in order to facilitate the transaction; or
- negotiated transactions between selling stockholders and purchasers
without a broker or dealer.
Ridgeway is an "underwriter" within the meaning of the Securities Act in
connection with its sale of the shares purchased from us described in this
prospectus supplement. Broker-dealers or other persons acting on the behalf of
parties that participate in the distribution of the shares may also be deemed to
be underwriters. Any commissions or profits they receive on the resale of the
shares may be deemed to be underwriting discounts and commissions under the
Securities Act.
During the time Ridgeway is engaged in distributing shares covered by this
prospectus, Ridgeway will comply with the requirements of the Securities Act and
Rule 10b-5 and Regulation M under the Exchange Act. Under those rules and
regulations, they:
- may not engage in any stabilization activity in connection with our
securities;
- must furnish each broker which offers shares of common stock covered
by this prospectus with the number of copies of this prospectus which
are required by each broker; and
- may not bid for or purchase any of our securities or attempt to induce
any person to purchase any of our securities other than as permitted
under the Exchange Act.
In connection with Ridgeway's purchase and potential resale of the shares
covered by this prospectus supplement, we will agree to indemnify and hold
harmless Ridgeway and each person who controls Ridgeway against certain
liabilities, including liabilities under the Securities Act, which may be based
upon, among other things, any untrue statement or alleged untrue statement of a
material fact or any omission or alleged omission of a material fact, unless
made or omitted in reliance upon written information provided to us by Ridgeway.
We have agreed to bear the expenses incident to the registration of the
shares, other than selling discounts and commissions. These expenses are
estimated to be $100,000.
USE OF PROCEEDS
We will use the proceeds of this offering as described in the prospectus.
See "Use of Proceeds" beginning on page 11.
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WHERE YOU CAN FIND MORE INFORMATION
The SEC allows us to "incorporate by reference" information that we file
with them, which means that we can disclose important information that we file
with them, which means that we can disclose important information to you by
referring you to those documents. The information incorporated by reference is
an important part of this prospectus supplement and the accompanying prospectus.
We incorporate the documents listed below, in addition to those indicated on
page 2 of the prospectus:
o Quarterly Report on Form 10-Q for the quarter ended September 30,
1999, filed on November 15, 1999.
o Report on Form 8-K dated January 11, 2000, filed on January 14, 2000.
MARKET FOR OUR COMMON STOCK
On February 1, 2000, the last reported sale price of our common stock on
the Nasdaq National Market was $19.5625 per share. Our common stock is listed on
the Nasdaq National Market under the symbol "AVIR." The common stock sold under
this prospectus supplement will be listed on the Nasdaq National Market after we
notify the Nasdaq National Market that the shares have been issued.
As of February 1, 2000, we had 16,684,190 shares of common stock
outstanding.
GENERAL
You should rely only on the information provided or incorporated by
reference in this prospectus supplement and the prospectus. We have not
authorized anyone else to provide you with different information. You should not
assume that the information in this prospectus supplement is accurate as of any
date other than the date on the front of these documents.
NEITHER THE SECURITIES EXCHANGE COMMISSION NOR ANY STATE SECURITIES
COMMISSION HAS APPROVED OR DISAPPROVED OF THE SECURITIES OR PASSED UPON THE
ACCURACY OR ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A
CRIMINAL OFFENSE.
The date of this prospectus supplement is February 2, 2000.
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TABLE OF CONTENTS
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PAGE
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PROSPECTUS SUPPLEMENT
Plan of Distribution .....................................S-1
Use of Proceeds...........................................S-2
Where You Can Find More Information.......................S-3
Market for Our Common Stock...............................S-3
General...................................................S-3
PROSPECTUS
Where You Can Find More Information.........................2
Summary.....................................................4
The Company.................................................4
The Offering................................................5
Risk Factors................................................6
Forward-Looking Statements.................................11
Use of Proceeds............................................11
Plan of Distribution.......................................13
Legal Matters..............................................13
Experts....................................................13
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