Press Release

BARCELONA, Spain, Apr 11, 2007 (BUSINESS WIRE) -- New data supporting the clinical development of telaprevir (VX-950), one of the most advanced investigational oral protease inhibitors for the treatment of hepatitis C virus (HCV) infection, will be presented at the 42nd Annual Meeting of the European Association for the Study of the Liver (EASL) in Barcelona this week. In total, nine abstracts related to telaprevir have been accepted for presentation at the EASL conference, including an abstract that describes telaprevir activity against genotypes 2, 3 and 4 in vitro. A late-breaker oral presentation will take place on Saturday, April 14 at 5:45 p.m. Central European Summer Time (11:45 a.m. Eastern Daylight Time). Vertex Pharmaceuticals Incorporated (Nasdaq: VRTX) is developing telaprevir in collaboration with Tibotec.

"Hepatitis C is a major global health problem with a significant unmet medical need. Despite treatment advancements in the last 10 years, there is an urgent need for new therapeutic options that can offer patients shorter course therapy and better efficacy," said John Alam, M.D., Executive Vice President, Medicines Development, and Chief Medical Officer of Vertex. "The data to be presented at EASL demonstrate the recent progress made in our clinical evaluation and understanding of telaprevir as a novel treatment for hepatitis C, underscoring our commitment to evaluate telaprevir's potential in important sub-populations, such as those with genotype non-1 hepatitis C."

Telaprevir is one of the most advanced specifically targeted antiviral therapies for HCV (STAT-C). STAT-Cs represent a new approach to hepatitis C treatment by directly targeting the enzymes the virus uses to replicate.

Oral Presentation: Telaprevir Demonstrates Potency Against Genotype 2, 3 and 4 in vitro

Chao Lin, Ph.D., of Vertex, will present an abstract titled, "Telaprevir (VX-950) is a Potent Inhibitor of HCV-NS3 Proteases Derived from Genotype Non-1 HCV-Infected Patients" at 6:15 p.m. CEST (12:15 p.m. EDT) on Thursday, April 12.

"While genotype 1 accounts for the majority of hepatitis C cases, the proportion of those living with genotypes 2, 3 and 4 is significant," continued Dr. Alam. "In this in vitro study, telaprevir demonstrated similar potency against the NS3-4A protease derived from those patients with genotype 2, 3 and 4 to the in vitro results demonstrated with telaprevir in genotype 1. These results support our plans to begin to study telaprevir in genotypes 2, 3 and 4 in 2007."

Late-Breaker Presentation

A late-breaker presentation titled, "Results of an Interim Analysis of a Phase 2 Study of Telaprevir (VX-950) with Peginterferon alfa-2a and Ribavirin in Previously Untreated Subjects with Hepatitis C," will be presented by John McHutchison, M.D., Principal Investigator for the PROVE 1 study and Director of Gastroenterology and Hepatology Research at Duke Clinical Research Institute, on Saturday, April 14 at 5:45 p.m. CEST (11:45 a.m. EDT).

In accordance with EASL embargo policy, these data remain under embargo until conclusion of the late-breaker session on Saturday, April 14 at 6:00 p.m. CEST (12:00 p.m. EDT).

Additional Telaprevir Presentations

Additional data presented at EASL will include viral kinetic data that continue to support further evaluation of telaprevir-based therapy to clear the hepatitis C virus with shorter treatment duration, and in vivo and in vitro viral replication and viral sequencing dynamic modeling studies that suggest telaprevir-resistant variants have reduced replication capacity compared to wild-type HCV. Poster presentations will begin on Thursday, April 12.

-- "Novel Mode of Viral Decline During Telaprevir (VX-950) and Peg-IFN Combination Treatment Predicted by a New Combined Intracellular and Cellular Hepatitis C Viral Dynamics Model," will be presented by A.U. Neumann of Bar-llan University, Israel.

-- "Telaprevir (VX-950)-Resistant Variants Exhibit Reduced Replication Capacity Compared to Wild-Type HCV in Vivo and In Vitro," will be presented by Chao Lin of Vertex.

-- "Ultrasound Evaluation of Perihepatic Lymph Nodes During Antiviral Therapy with the Protease Inhibitor Telaprevir (VX-950) in Patients with Chronic Hepatitis C Infection," will be presented by Mireen Friedrich-Rust and Nicole Forestier, Saarland University Hospital, Germany.

-- "Neopterin and ALT as Markers of Inflammation in Chronic Hepatitis C Patients During Administration of the HCV NS3-4A Protease Inhibitor Telaprevir (VX-950) in Combination with PegInterferon Alpha 2A," will be presented by Huub Gelderblom, University of Amsterdam.

-- An oral presentation titled, "Molecular Basis for VX-950 Resistance," will be presented by Stefan Zeuzem, Saarland University Hospital, Germany, at 5:15 p.m. CEST (11:15 a.m. EDT) on Friday, April 13.

Two presentations discussing in vitro data of telaprevir in combination with other oral direct antiviral therapies will also take place during EASL.

Full abstracts are available on the EASL website: www.easl.ch/liver-meeting.

Webcast of Investor Presentation

Vertex intends to provide a live webcast of its investor presentation from Barcelona beginning at 7:30 p.m. CEST (1:30 p.m. EDT) on Saturday, April 14. The presentation may be accessed from the 'Events Calendar' on the homepage of Vertex's website at www.vrtx.com. A replay of the webcast will also be available on the Company's website until April 27, 2007. To ensure a timely connection, it is recommended that users register at least 15 minutes prior to the scheduled webcast.

About Telaprevir (VX-950)

Telaprevir (VX-950) is an investigational oral inhibitor of HCV protease, an enzyme essential for viral replication, and is one of the most advanced investigational agents in development that specifically targets HCV. Vertex is conducting a global Phase 2b clinical development program for telaprevir consisting of three large clinical trials that are expected to enroll approximately 1,000 patients with HCV at clinical centers in the U.S., Canada and E.U. In February 2007, Vertex announced the initiation of PROVE 3, designed to enroll 440 genotype-1 HCV patients who have previously received interferon based therapy in the U.S., Canada and E.U. Vertex completed enrollment of 250 patients in the U.S.-based PROVE 1 trial in September 2006. The 320-patient, European-based PROVE 2 trial completed enrollment in January 2007. In these clinical trials, telaprevir is being dosed as 750 mg every 8 hours in combination with peginterferon alfa-2a (Pegasys(R)), both with and without ribavirin (Copegus(R)).

Vertex retains commercial rights to telaprevir in North America. Vertex and Tibotec are collaborating to develop and commercialize telaprevir in Europe, South America, Australia, the Middle East, and other countries. Vertex is collaborating with Mitsubishi Pharma to develop and commercialize telaprevir in Japan and certain Far East countries.

About Hepatitis C

Hepatitis C is a liver disease caused by infection with hepatitis C virus (HCV), which is also found in the blood of people with the disease. HCV, a serious public health concern affecting 170 million people worldwide, is spread through direct contact with the blood of an infected person. Though many people with hepatitis C may not experience symptoms, others may have symptoms late in the course of the disease such as jaundice, abdominal pain, fatigue and fever. Hepatitis C significantly increases a person's risk of developing chronic liver disease, cirrhosis, liver cancer and early death.

About Vertex

Vertex Pharmaceuticals Incorporated is a global biotechnology company committed to the discovery and development of breakthrough small molecule drugs for serious diseases. The Company's strategy is to commercialize its products both independently and in collaboration with major pharmaceutical companies. Vertex's product pipeline is focused on viral diseases, inflammation, autoimmune diseases, cancer, pain and bacterial infection. Vertex co-discovered the HIV protease inhibitor, Lexiva, with GlaxoSmithKline.

Vertex's press releases are available at www.vrtx.com.

About Tibotec

Tibotec Pharmaceuticals Ltd., based in Cork, Ireland, is a pharmaceutical research and development company. Tibotec is dedicated to the discovery and development of innovative HIV/AIDS drugs and anti-infectives for diseases of high unmet medical need. The Company's main research and development facilities are in Mechelen, Belgium with offices in Yardley, PA.

For further information on Tibotec, please visit: www.tibotec.com

Safe Harbor Statement

This press release may contain forward-looking statements, including statements that (i) non-clinical, in vitro studies evaluating telaprevir against NS3 4A proteases in patients with genotype 2, 3 and 4 support Vertex's planned clinical evaluation of TVR in other genotypes; (ii) viral kinetic data will continue to support further evaluation of telaprevir combination therapy to clear the virus with shorter treatment duration; (iii) in vivo and in vitro viral replication and viral sequencing dynamic modelling studies suggest that telaprevir-resistant variants have reduced replication capacity compared to wild-type HCV; and (iv) Vertex expects the combined PROVE program to increase to more than 1,000 the number of patients in telaprevir clinical trials. While management makes its best efforts to be accurate in making forward-looking statements, such statements are subject to risks and uncertainties that could cause the actual results of studies to vary materially. Those risks and uncertainties include, among other things, the risk that observed outcomes in in vitro analyses or in clinical investigations of small numbers of patients will not be reflected in clinical trials involving larger numbers of patients, that unexpected and adverse outcomes in other ongoing clinical and nonclinical studies, and other risks listed under Risk Factors in Vertex's Form 10-K filed with the Securities and Exchange Commission on March 1, 2007. Vertex disclaims any obligation to update the information contained in this press release as new data become available.

SOURCE: Vertex Pharmaceuticals Incorporated

Vertex Contacts:
Lynne H. Brum, 617-444-6614
VP, Strategic Communications
or
Michael Partridge, 617-444-6108
Director, Corporate Communications
or
Lora Pike, 617-444-6755
Manager, Investor Relations
or
Patricia Farrell, 617-444-6533
Director, Public Relations
or
Zachry Barber, 617-444-6470
Senior Media Relations Specialist
or
Tibotec Contact:
Karen Manson, +32 15 461 019
Mobile +32 479 894 799
VP, Communications and Public Affairs

Copyright Business Wire 2007

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