<PAGE>
Filed Pursuant to Rule 424(b)(3)
REGISTRATION NO. 333-37794
PROSPECTUS SUPPLEMENT NO. 3 DATED SEPTEMBER 26, 2000 TO THE
PROSPECTUS DATED AUGUST 1, 2000 OF
VERTEX PHARMACEUTICALS INCORPORATED
This Prospectus Supplement No. 3 amends the information in the table under
the caption "Selling Holders" in the Prospectus dated August 1, 2000 by
deleting the information contained in the table regarding the Selling
Security Holders with respect to the principal amount of notes and common
stock of Vertex Pharmaceuticals Incorporated and substituting therefor the
following table:
<TABLE>
<CAPTION>
NUMBER OF SHARES OF
COMMON STOCK ISSUABLE
PRINCIPAL AMOUNT OF NOTES UPON CONVERSION OF THE
BENEFICIALLY OWNED NOTES THAT MAY BE
NAME OF SECURITY HOLDER AND OFFERED(1) OFFERED(2)
----------------------- ------------------------- ----------------------
<S> <C> <C>
AIG SoundShore Holdings Ltd. $1,670,000 41,418
AIG SoundShore Opportunity Holding
Fund Ltd. $2,400,000 59,523
AIG SoundShore Strategic Holding
Fund Ltd. $1,400,000 34,722
Alta Partners Holdings, Inc. (3) $5,000,000 124,007
American Masters Fund "AG Absolute
Return Series" Limited $1,000,000 24,801
Angelo, Gordon & Co., L.P. $500,000 12,400
Argent Classic Convertible Arbitrage
Fund (Bermuda) L.P. $5,000,000 124,007
Bear, Stearns & Co. Inc.(4) $500,000 12,400
BNP Arbitrage SNC $6,500,000 161,210
BP Amoco PLC Master Trust $2,200,000 54,563
BT Equity Opportunities $1,000,000 24,801
BT Equity Strategies $1,000,000 24,801
CFFX, LLC $3,250,000 80,605
CIBC World Markets $3,250,000 80,605
Credit Suisse First Boston Corporation $3,800,000 94,246
The Common Fund F/A/O Absolute
Return Fund $300,000 7,440
</TABLE>
-1-
<PAGE>
<TABLE>
<CAPTION>
NUMBER OF SHARES OF
COMMON STOCK ISSUABLE
PRINCIPAL AMOUNT OF NOTES UPON CONVERSION OF THE
BENEFICIALLY OWNED NOTES THAT MAY BE
NAME OF SECURITY HOLDER AND OFFERED(1) OFFERED(2)
----------------------- ------------------------- ----------------------
<S> <C> <C>
Deutsche Bank Securities $4,900,000 121,527
Donaldson, Lufkin & Jenrette
Securities Corp. $500,000 12,400
Estate of James Campbell $950,000 23,561
First Albany Corporation $111,000 2,752
Grace Brothers, Ltd. $1,500,000 37,202
Helix Convertible Opportunities Fund Ltd $910,000 22,569
Helix Convertible Opportunities, L.P. $1,790,000 44,394
Highbridge International LLC $9,250,000 229,414
ITG, Inc. $200,000 4,960
Jefferies & Company $200,000 4,960
J.P. Morgan Securities, Inc. $4,375,000 108,506
KBC Financial Products $5,000,000 124,007
Key Asset Management Inc. $200,000 4,960
Lazard Freres & Cie Paris (5) $1,500,000 37,202
LDG Limited $200,000 4,960
McMahan Securities Co., L.P. $1,600,000 39,682
Merrill Lynch, Pierce, Fenner and
Smith Inc. (4) $4,105,000 101,810
MichaelAngelo, L.P. $1,750,000 43,402
Morgan Stanley & Co. $10,000,000 248,015
</TABLE>
-2-
<PAGE>
<TABLE>
<CAPTION>
NUMBER OF SHARES OF
COMMON STOCK ISSUABLE
PRINCIPAL AMOUNT OF NOTES UPON CONVERSION OF THE
BENEFICIALLY OWNED NOTES THAT MAY BE
NAME OF SECURITY HOLDER AND OFFERED(1) OFFERED(2)
----------------------- ------------------------- ----------------------
<S> <C> <C>
New York Life Insurance and
Annuity Corporation $1,100,000 27,281
New York Life Insurance Company $6,500,000 161,210
Quattro Fund Ltd $500,000 12,400
R2 Investments, LDC $27,600,000 684,523
Raphael II, Ltd. $1,000,000 24,801
RCG Multi-Strategy Account, L.P. $750,000 18,601
Robertson Stephens (3) $12,500,000 310,019
Salomon Brothers Asset Management, Inc. $36,930,000 915,922
SG Cowen Securities (3) $10,000,000 248,015
TQA Master Fund, LTD $2,700,000 66,964
TQA Master Plus Fund, LTD $1,000,000 24,801
Tribeca Investments LLC $8,500,000 210,813
UBS Warburg LLC $5,500,000 136,408
White River Securities LLC $500,000 12,400
Zurich HFR Master Fund $100,000 2,480
</TABLE>
(1) The number of securities beneficially owned is determined under the rules
of the SEC and the information is not necessarily indicative of
beneficial ownership for any other purpose. Under those rules, beneficial
ownership includes any securities as to which the individual has sole or
shared voting power or investment power and also any securities which the
individual has the right to acquire within 60 days through the exercise
of any stock option or other right. The inclusion in the table of
securities, however, does not constitute an admission that the selling
holders are direct or indirect beneficial owners of those securities. The
selling holders have sole voting power and investment power with respect
to all securities or capital stock listed as owned by the selling
holders.
-3-
<PAGE>
(2) Adjusted to reflect the two-for-one stock split of our common stock
effected by way of a stock dividend distributed on August 31, 2000, and
the resulting adjustment in the conversion price of the notes from $80.64
to $40.32 per share.
(3) As of September 11, 2000, Alta Partners Holdings, Inc. beneficially
owned 117,700 shares of our Common Stock. These shares are not part
of this offering.
(4) Acted as one of the initial purchasers of the notes.
(5) As of May 22, 2000, Lazard Freres & Cie Paris owned 7,360 shares of our
common stock. These shares are not part of this offering.
This Prospectus Supplement No. 3 should be read in conjunction with the
Prospectus dated August 1, 2000