<PAGE>
Exhibit 99
November 10, 2000
Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549
Commissioners:
We are aware that our report dated October 24, 2000 on our review of interim
financial information of Vertex Pharmaceuticals Incorporated (the "Company")
as of and for the period ended September 30, 2000 and included in the
Company's quarterly report on Form 10-Q for the quarter then ended is
incorporated by reference in its registration statements on Forms S-8 (File
Nos. 33-48030, 33-48348, 33-65742, 33-93224, 33-12325, 333-27011, 333-56179
and 333-79549) and Form S-3 (File No. 333-37794). Pursuant to Rule 436(c)
under the Securities Act of 1933, this report should not be considered a part
of the registration statement prepared or certified by us within the meaning
of Sections 7 and 11 of that Act.
Yours very truly,
/s/ PricewaterhouseCoopers LLP
Boston, MA
