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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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


                                 FORM 10-Q/A


                QUARTERLY REPORT UNDER SECTION 13 OR 15(D) OF THE
                         SECURITIES EXCHANGE ACT OF 1934



   For Quarter Ended: MARCH 31, 1996           Commission File Number 0-19319


                       VERTEX PHARMACEUTICALS INCORPORATED
             (Exact name of registrant as specified in its charter)

              Massachusetts                                04-3039129
              -------------                                ----------
    (State or other jurisdiction of                    (I.R.S. Employer
    incorporation or organization)                     Identification No.)



             130 WAVERLY STREET, CAMBRIDGE, MASSACHUSETTS 02139-4242
             ------------------------------------------------------
          (Address of principal executive offices, including zip code)


                                 (617) 577-6000
                                 --------------
              (Registrant's telephone number, including area code)

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.

                               YES X   NO 
                                  ---    ---

     Indicate the number of shares outstanding of each of the issuer's classes
of common stock, as of the latest practicable date.

Common Stock, par value $.01 per share                     17,368,453
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              Class                                 Outstanding at May 9, 1996


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                                    PART II.

                                OTHER INFORMATION


Item 6. Exhibits:

        
        10.2  Research and Development Agreement, dated April 13, 1993, between
              the Registrant and Kissei Pharmaceutical Co., Ltd. (filed
              herewith with certain confidential information omitted).

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                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this amendment to be signed on its behalf by the
undersigned thereunto duly authorized.

                                      VERTEX PHARMACEUTICALS INCORPORATED




Date:  May 17, 1996                   /s/ Thomas G. Auchincloss, Jr.
                                     ------------------------------
                                     Thomas G. Auchincloss, Jr.
                                     Senior Director of Finance and Treasurer
                                     (Principal Financial Officer)





                                     /s/ Hans D. van Houte
                                     ------------------------------
                                     Hans D. van Houte
                                     Controller
                                     (Principal Accounting Officer)



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