<PAGE>
Filed by: Millennium Pharmaceuticals, Inc.
Pursuant to Rule 425 under the Securities Act of 1933
Subject Company: Millennium Pharmaceuticals, Inc.
Commission File No. 000-28494
MPMX STOCK Q&A'S - FOR MILLENNIUM EMPLOYEES WITH MPMX SHARES OR OPTIONS
This is a follow-up to the MPMx Information Statement and MPI Prospectus sent to
all MPMx Share & Option holders on May 4, 2000 containing information about the
merger, the stock conversion and other relevant information.
The following Q&A's are intended to further explain what Millennium employees
can expect regarding the conversion of MPMx shares and options to MPI shares and
options.
Q1: When do we expect the merger closing to be effective?
A1: The closing will be effective on the 20th business day following the mailing
of the Statement & Prospectus which occurred on May 4, 2000. Therefore, the
closing is planned to be effective June 2, 2000.
Q2: How does the conversion work? What MPI stock price is used in the
conversion?
A2: For each MPMx share of Class B Common stock, you will receive 0.4 shares of
MPI Common Stock. The exercise price for any options will be 2.5 times the
original price.
Example:
MPMx Shares = 1,000 shares @ $1.10/share = $1,100.00 option cost
Converted into
MPI Shares = 400 shares (1,000 *0.4) @ $2.75($1.10 * 2.5)/share =
$1,100.00 option cost
Q3: When will we know how many MPI shares we have?
A3: On June 2, 2000 individual stock and option statements will be sent showing
the resulting MPI shares and options you will receive from the conversion.
However, as the conversion rate has been determined above, you can calculate how
many shares or options you will receive.
Q4: When will we be able to sell converted MPI shares or exercise vested
options?
A4: Beginning June 5, 2000, any vested converted MPI shares can be sold through
our broker Salomon Smith Barney (SSB). YOU MUST USE SSB TO EXECUTE ANY TRADES
BECAUSE
<PAGE>
OF VESTING REQUIREMENTS. Converted certificates received from the transfer agent
must be presented to SSB in order for you to receive your proceeds from any
sales. Please contact them directly to open an account.
On this same day, any vested converted options may be exercised through the SSB
web page, voice system or by calling the Boston office directly.
Q5: What will happen to the options that were early exercised?
A5: You will receive MPI stock certificates for the options you early exercised.
Beginning June 5, 2000, any vested converted MPI shares can be sold through SSB.
However, before any trade can be executed, any outstanding loans must be paid in
full. The loan may be repaid with a portion of your proceeds received from the
sale.
Q6: How long before I receive the proceeds from stock sales?
A6: Generally, the proceeds from same day sales of stock options are received in
less than two weeks. Proceeds from the sale of shares are received in a month's
time because these shares are restricted. Also, there could be delays if you do
not deposit and sign over your certificates to SSB as mentioned above.
Q7: What will happen to the Celebration Grants?
A7: The Celebration Grants will convert to MPI options, but the vesting has not
been accelerated as a result of the merger. This is similar to the MBio
Celebration Grants converted in December 1999. Options will become exercisable
December 2005 or at a date approved by the Board of Directors, whichever comes
first.
Q8: When will MPI stock certificates be delivered to individuals?
A8: Stock certificates will be mailed by our transfer agent to your home
beginning on June 2, 2000. (If your address has changed recently or you believe
that it may be out of date on the stock option records please contact Han
Meskell in Finance.) If after several weeks, you still have not received your
stock certificate, you must contact the Transfer Agent directly to replace lost
certificates. Please contact them at 1-877-282-1168.
Q9: Will I get new stock documentation for the converted MPI shares?
A9: No, the MPMx grant agreements apply to the converted MPI shares.
Q10: How will loans be treated?
A10: Loans will be transferred to MPI. All provisions will remain the same.
Please contact Han Meskell if you would like to pay off your loan early.
<PAGE>
Q11: Once I know exactly how my shares have converted, who can I talk to if I
have further questions?
A11: Colleen DeSimone or Han Meskell in Stock Administration, Pete Castrichini
or Kathy Gallo in Human Resources, or the Callanan Group at Salomon Smith Barney
at 617-570-9533.
ADDITIONAL INFORMATION AND WHERE TO FIND IT
Millennium Pharmaceuticals has filed a Registration Statement on SEC
Form S-4 in connection with its merger with Millennium Predictive Medicine, and
Millennium Pharmaceuticals and Millennium Predictive Medicine have mailed an
Information Statement/Prospectus to stockholders of Millennium Predictive
Medicine containing information about the merger. Investors and stockholders of
Millennium Predictive Medicine are urged to read the Registration Statement and
the Information Statement/Prospectus carefully. The Registration Statement and
the Information Statement/Prospectus contain important information about
Millennium Pharmaceuticals, Millennium Predictive Medicine, the merger and
related matters. Investors and stockholders of Millennium Predictive Medicine
are able to obtain free copies of these documents through the web site
maintained by the U.S. Securities and Exchange Commission at http//www.sec.gov.
Free copies of these documents may also be obtained from Millennium
Pharmaceuticals by requesting them in writing or by telephone from Millennium
Pharmaceuticals at the following address:
Millennium Pharmaceuticals, Inc.
75 Sidney Street
Cambridge, MA 02139
Tel.: (617) 679-7000
Attention: Corporate Secretary
website: http://www.mlnm.com
Millennium Pharmaceuticals also files annual, quarterly and special
reports, proxy statements and other information with the SEC. You may read and
copy any reports, statements or other information that Millennium
Pharmaceuticals has filed at the SEC's public reference rooms. Please call the
SEC at 1-800-SEC-0330 for information on the public reference rooms or visit the
following locations of the SEC:
<TABLE>
<S> <C> <C>
Public Reference Room New York Regional Office Chicago Regional Office
450 Fifth Street, N.W. 7 World Trade Center Citicorp Center
Room 1024 Suite 1300 500 West Madison Street
Washington, DC 20549 New York, New York 10048 Suite 1400
Chicago, Illinois 60661-2511
</TABLE>
You may also obtain copies of this information by mail from the Public
Reference Section of the SEC, 450 Fifth Street, N.W., Room 1024, Washington,
D.C. 20549, at prescribed rates. Millennium Pharmacueticals' SEC filings are
also available to the public from commercial document retrieval services and at
the web site maintained by the SEC at HTTP://WWW.SEC.GOV.
