<PAGE>
PROSPECTUS SUPPLEMENT Filed pursuant to Rule 424(b)(3)
(TO PROSPECTUS DATED APRIL 27, 2000) Registration No. 333-31344
MILLENNIUM PHARMACEUTICALS, INC.
$400,000,000 Principal Amount 5.50% Convertible Subordinated Notes
Due January 15, 2007
4,753,920 Shares of Common Stock issuable upon conversion of the Notes
211,554 Shares of Common Stock issuable upon exercise of outstanding
warrants to purchase common stock
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This prospectus supplement relates to resales by selling holders of:
- our 5.50% Convertible Subordinated Notes due January 15, 2007;
- our common stock into which the notes are convertible; and
- our common stock issuable upon exercise of warrants to purchase our
common stock held by GATX Capital Corporation and MM Ventures
This prospectus supplement should be read in conjunction with the
prospectus dated April 27, 2000, which is to be delivered with this prospectus
supplement.
SEE "RISK FACTORS" BEGINNING ON PAGE 6 OF THE PROSPECTUS TO READ ABOUT
FACTORS YOU SHOULD CONSIDER BEFORE BUYING THE NOTES OR OUR COMMON STOCK.
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Neither the Securities and Exchange Commission nor any other regulatory
body has approved or disapproved of these securities or passed upon the accuracy
or adequacy of this prospectus. Any representation to the contrary is a criminal
offense.
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The information in the table appearing in the prospectus under the heading
"Selling Holders" is superseded in part by the information appearing in the
following table:
<TABLE>
<CAPTION>
Number of
Percentage Shares of
of the Common Number of Number of Percentage
Notes Notes Notes Stock Shares of Shares of of Shares of
Beneficially Beneficially Beneficially Beneficially Common Common Stock Common Stock
Owned Notes Owned Owned Owned Stock Beneficially Beneficially
Prior to Offered After After the Prior to Offered Owned After Owned After
Selling Offering Hereby Offering(1) Offering Offering Hereby Offering(1) Offering(1)
Securityholder (in $1,000) (in $1,000) (in $1,000)
<S> <C> <C> <C> <C> <C> <C> <C> <C>
Amoco Corp. 656 656 0 0 7,796 7,796 0 0
Master Trust
Arkansas 2,132 2,132 0 0 25,338 25,338 0 0
Teachers
Retirement
System
Associated 450 450 0 0 5,348 5,348 0 0
Electric & Gas
Insurance
Services Limited
Baptist Health 103 103 0 0 1,224 1,224 0 0
of South Florida
Boston Museum 83 83 0 0 986 986 0 0
of Fine Arts
Champion 393 393 0 0 4,670 4,670 0 0
International
Corp.
City University 87 87 0 0 1,033 1,033 0 0
of New York
David Lipscomb 105 105 0 0 1,247 1,247 0 0
University
General
Endowment
EQAT Alliance 2,955 2,955 0 0 35,119 35,119 0 0
Growth & Income
Equitable Life 1,925 1,925 0 0 22,878 22,878 0 0
Assurance
Separate
Account -
Convertible
EQAT Alliance 1,605 1,605 0 0 19,075 19,075 0 0
Growth Investors
Engineers Joint 289 289 0 0 3,434 3,434 0 0
Pension Fund
Goldman Sachs 14,000 14,000 0 0 166,387 166,387 0 0
and Company
Grady Hospital 136 136 0 0 1,616 1,616
HBK Master Fund 2,500 2,500 0 0 29,712 29,712 0 0
L.P.
</TABLE>
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<PAGE>
<TABLE>
<CAPTION>
Number of
Percentage Shares of
of the Common Number of Number of Percentage
Notes Notes Notes Stock Shares of Shares of of Shares of
Beneficially Beneficially Beneficially Beneficially Common Common Stock Common Stock
Owned Notes Owned Owned Owned Stock Beneficially Beneficially
Prior to Offered After After the Prior to Offered Owned After Owned After
Selling Offering Hereby Offering(1) Offering Offering Hereby Offering(1) Offering(1)
Securityholder (in $1,000) (in $1,000) (in $1,000)
<S> <C> <C> <C> <C> <C> <C> <C> <C>
Jeffries & Co. 656 656 0 0 7,796 7,796 0 0
Inc.
KBC Financial 2,000 2,000 0 0 23,769 23,769 0 0
Products
Local 56 56 0 0 665 665 0 0
Initiatives
Support
Corporation
Lord Abbett 7,600 7,600 0 0 90,324 90,324 0 0
Bond Debenture
Fund
Maryland State 3,397 3,397 0 0 40,372 40,372 0 0
Retirement
System
New Orleans 139 139 0 0 1,651 1,651 0 0
Firefighters
Nicholas-Applegate 738 738 0 0 8,770 8,770 0 0
Convertible Fund
Occidental 240 240 0 0 2,852 2,852 0 0
Petroleum
Physicians Life 226 226 0 0 2,685 2,685 0 0
Pilgrim 2,765 2,765 0 0 32,861 32,861 0 0
Convertible Fund
Sagamore Hill 6,250 6,250 0 0 74,280 74,280 0 0
Hub Fund Ltd.
Robertson 8,000 8,000 0 0 95,078 95,078 0 0
Stephens
San Diego City 580 580 0 0 6,893 6,893 0 0
Retirement
San Diego 1,408 1,408 0 0 16,733 16,733 0 0
County
Convertible
Shell Pension 376 376 0 0 4,468 4,468 0 0
Trust
</TABLE>
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<PAGE>
<TABLE>
<CAPTION>
Number of
Percentage Shares of
of the Common Number of Number of Percentage
Notes Notes Notes Stock Shares of Shares of of Shares of
Beneficially Beneficially Beneficially Beneficially Common Common Stock Common Stock
Owned Notes Owned Owned Owned Stock Beneficially Beneficially
Prior to Offered After After the Prior to Offered Owned After Owned After
Selling Offering Hereby Offering(1) Offering Offering Hereby Offering(1) Offering(1)
Securityholder (in $1,000) (in $1,000) (in $1,000)
<S> <C> <C> <C> <C> <C> <C> <C> <C>
The Frist 285 285 0 0 3,387 3,387 0 0
Foundation
Tribeca 29,000 24,000 0 0 344,659 285,235 0 0
Investments LLC
Wake Forest 692 692 0 0 8,224 8,224 0 0
University
Writers 179 179 0 0 2,127 2,127 0 0
Guild-Industry
Health Fund
</TABLE>
(1) We do not know if, when or in what amounts a selling securityholder
may offer securities for sale and we do not know that the selling
securityholders will sell any or all of the securities offered hereby. Because
the selling securityholders may offer all or some of the securities pursuant to
this prospectus, and because there are currently no other agreements,
arrangements or understandings with respect to the sale of any of the securities
that will be held by the selling securityholders, no estimate can be given as to
the amount of the securities that will be held by the selling securityholders
after completion of the offering made by this prospectus. However, for purposes
of this table, we have assumed that, after completion of the offering, no
securities will be held by the selling securityholders.
The date of this prospectus supplement is June 2, 2000.
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