Exhibit 23.6

                          [Goldman Sachs Letterhead]

PERSONAL AND CONFIDENTIAL

May 21, 2001

Board of Directors
Aurora Biosciences Corporation
11010 Torreyana Road
San Diego, California 92121

Re: Initial Filing Registration Statement on Form S-4 of Vertex Pharmaceuticals
    Incorporated ("Vertex") relating to the Vertex Common Stock (as defined
    below) being registered in connection with the transaction described below

Gentlemen:

Reference is made to our opinion letter dated April 28, 2001 with respect to the
fairness from a financial point of view to the holders of the outstanding shares
of Common Stock, par value $0.001 per share (the "Shares"), of Aurora
Biosciences Corporation (the "Company") of the exchange ratio of 0.62 shares of
Common Stock, par value $0.01 per share ("Vertex Common Stock"), of Vertex
Pharmaceuticals Incorporated ("Vertex") to be received for each Share pursuant
to the Agreement and Plan of Merger, dated as of April 29, 2001, among Vertex,
Ahab Acquisition Sub, Inc., a wholly-owned subsidiary of Vertex, and the
Company.

The foregoing opinion letter is provided for the information and assistance of
the Board of Directors of the Company in connection with its consideration of
the transaction contemplated therein and is not to be used, circulated, quoted
or otherwise referred to for any other purpose, nor is it to be filed with,
included in or referred to in whole or in part in any registration statement,
proxy statement or any other document, except in accordance with our prior
written consent. We understand that the Company has determined to include our
opinion in the above-referenced Registration Statement and has asked for our
consent.

In that regard, we hereby consent to the reference to the opinion of our Firm
under the captions "Summary of the Joint Proxy Statement-Prospectus",
"Background of the Merger" and "Opinion of Aurora's Financial Advisor" and to
the inclusion of the foregoing opinion in the Joint Proxy Statement/Prospectus
included in the above-mentioned Registration Statement. Notwithstanding the
foregoing, it is understood that our consent is being



Board of Directors
Aurora Biosciences Corporation
May 21, 2001
Page Two

delivered solely in connection with the filing of the above-mentioned version
of the Registration Statement and that our opinion is not to be used,
circulated, quoted or otherwise referred to for any other purpose, nor is it
to be filed with, included in or referred to in whole or in part in any
registration statement (including any subsequent amendments to the
above-mentioned Registration Statement), proxy statement or any other
document, except in accordance with our prior written consent.

In giving such consent, we do not thereby admit that we come within the category
of persons whose consent is required under Section 7 of the Securities Act of
1933 or the rules and regulations of the Securities and Exchange Commission
thereunder.

Very truly yours,

/s/ Goldman, Sachs & Co.
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(GOLDMAN, SACHS & CO.)