Exhibit 99


January 16, 2001


Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549

Commissioners:


We are aware that our reports dated April 28, 2000, July 25, 2000 and October
24, 2000 on our reviews of interim financial information of Vertex
Pharmaceuticals Incorporated (the "Company") for the periods ended March 31,
2000, June 30, 2000, and September 30, 2000, respectively, and included in
the Company's quarterly report on Form 10-Q for the quarters then ended are
incorporated by reference in its Amendment No. 1 to the registration
statement on Form S-3 (File No. 333-49844) dated January 16, 2001.


Yours very truly,


/s/ PricewaterhouseCoopers LLP