Press Release

-Advisory Committee for the Food and Drug Administration reviewing the telaprevir New Drug Application for the treatment of hepatitis C-

CAMBRIDGE, Mass.--(BUSINESS WIRE)-- Vertex Pharmaceuticals Incorporated (NASDAQ: VRTX) announced that NASDAQ today halted trading of the company's common stock. The United States Food and Drug Administration's (FDA) Antiviral Drugs Advisory Committee meets today in Silver Spring, MD to review the New Drug Application (NDA) for telaprevir.

The NDA for telaprevir was granted Priority Review by the FDA, and the FDA is expected to make a decision on the approval of telaprevir by May 23, 2011 under the Prescription Drug User Fee Act (PDUFA). The NDA includes data from three registration studies, ADVANCE, ILLUMINATE and REALIZE, which evaluated telaprevir in combination with pegylated-interferon and ribavirin in people who were not treated previously and in the three major subgroups of people who were treated previously but who were not cured with currently available medicines — relapsers, partial responders and null responders. For complete information on the telaprevir clinical trials or a fact sheet on the trial designs visit: http://investors.vrtx.com/press.cfm.

About Hepatitis C

Hepatitis C is a serious liver disease caused by the hepatitis C virus, which is spread through direct contact with the blood of infected people and ultimately affects the liver.ⁱ Chronic hepatitis C can lead to serious and life-threatening liver problems, including liver damage, cirrhosis, liver failure or liver cancer.ⁱ Though many people with hepatitis C may not experience symptoms, others may have symptoms such as fatigue, fever, jaundice and abdominal pain.ⁱ

Unlike HIV and hepatitis B virus, chronic hepatitis C is curable.ⁱⁱ However, approximately 60 percent of people who undergo treatment with an initial 48-week regimen of pegylated-interferon and ribavirin, the currently approved medicines for genotype 1 hepatitis C, do not achieve SVR,^iii,iv,v or viral cure.^vi If treatment is not successful and a person does not achieve a viral cure, they remain at an increased risk for progressive liver disease.^vii,viii

More than 170 million people worldwide are chronically infected with hepatitis C.^vi In the United States, nearly 4 million people have chronic hepatitis C and 75 percent of them are unaware of their infection.^ix Hepatitis C is four times more prevalent in the U.S. compared to HIV.^ix The majority of people with hepatitis C in the United States were born between 1946 and 1964, accounting for two of every three people with chronic hepatitis C.^x Hepatitis C is the leading cause of liver transplantations in the United States and is reported to contribute to 4,600 to 12,000 deaths annually. ^xi,xii By 2029, total annual medical costs in the United States for people with hepatitis C are expected to more than double, from $30 billion in 2009 to approximately $85 billion.^ix

About Telaprevir

Telaprevir is an investigational, oral inhibitor that acts directly on the hepatitis C virus protease, an enzyme essential for viral replication. More than 2,800 people with hepatitis C have received telaprevir-based combination therapy as part of Phase 2 and Phase 3 studies. The Phase 3 registration studies, ADVANCE, ILLUMINATE and REALIZE, evaluated telaprevir (750 mg, taken three times daily) in combination with Pegasys^® (pegylated-interferon alfa-2a) and Copegus^® (ribavirin) in people with hepatitis C who had not been treated before as well as those who were treated before but not cured with a prior treatment course of pegylated-interferon and ribavirin.

Vertex is developing telaprevir in collaboration with Tibotec BVBA and Mitsubishi Tanabe Pharma. Vertex has rights to commercialize telaprevir in North America. Through its affiliate, Janssen, Tibotec has rights to commercialize telaprevir in Europe, South America, Australia, the Middle East and certain other countries. Mitsubishi Tanabe Pharma has rights to commercialize telaprevir in Japan and certain Far East countries.

About Vertex

Vertex creates new possibilities in medicine. Our team aims to discover, develop and commercialize innovative therapies so people with serious diseases can lead better lives.

Vertex scientists and our collaborators are working on new medicines to cure or significantly advance the treatment of hepatitis C, cystic fibrosis, epilepsy and other life-threatening diseases.

Founded more than 20 years ago in Cambridge, MA, we now have ongoing worldwide research programs and sites in the U.S., U.K. and Canada.

Special Note About Forward-looking Statements

This press release contains forward-looking statements, including a statement regarding the expectation that the FDA will make a decision on approval of telaprevir by May 23, 2011. While the company believes the forward-looking statements contained in this press release are accurate, there are a number of factors that could cause actual events or results to differ materially from those indicated by such forward-looking statements. Those risks and uncertainties include, among other things, that Vertex could experience unforeseen delays in obtaining approval to market telaprevir and the other risks listed under Risk Factors in Vertex's annual report and quarterly reports filed with the Securities and Exchange Commission and available through Vertex's website at www.vrtx.com. Vertex disclaims any obligation to update the information contained in this press release as new information becomes available.

PEGASYS^® and COPEGUS^® are registered trademarks of Hoffmann-La Roche.

VRTX-GEN

ⁱ Centers for Disease Control and Prevention. Hepatitis C Fact Sheet: CDC Viral Hepatitis. Available at: http://www.cdc.gov/hepatitis/HCV/PDFs/HepCGeneralFactSheet.pdf. Accessed March 21, 2011.
ⁱⁱ Pearlman BL and Traub N. Sustained Virologic Response to Antiviral Therapy for Chronic Hepatitis C Virus Infection: A Cure and So Much More. Clin Infect Dis. 2011 Apr;52(7):889-900.
ⁱⁱⁱ Manns MP, McHutchison JG, Gordon SC, et al. Peginterferon alfa-2b plus ribavirin compared with interferon alfa-2b plus ribavirin for initial treatment of chronic hepatitis C: a randomised trial. Lancet. 2001;358:958-965.
^iv Fried MW, Shiffman ML, Reddy KR, et al. Peginterferon alfa-2a plus ribavirin for chronic hepatitis C virus infection. N Engl J Med. 2002;347:975-982.
^v McHutchison JG, Lawitz EJ, Shiffman ML, et al; IDEAL Study Team. Peginterferon alfa-2b or alfa-2a with ribavirin for treatment of hepatitis C infection. N Engl J Med. 2009;361:580-593.
^vi Ghany MG, Strader DB, Thomas DL, Seeff, LB. Diagnosis, management and treatment of hepatitis C; An update. Hepatology. 2009;49 (4):1-40.
^vii Morgan TR, Ghany MG, Kim HY, Snow KK, Lindsay K, Lok AS. Outcome of sustained virological responders and non-responders in the Hepatitis C Antiviral Long-Term Treatment Against Cirrhosis (HALT-C) trial. Hepatology. 2008;50(Suppl 4):357A (Abstract 115).
^viii Veldt BJ, Heathcote J, Wedmeyer H. Sustained virologic response and clinical outcomes in patients with chronic hepatitis C and advanced fibrosis. Annals of Internal Medicine. 2007; 147: 677-684.
^ix Institute of Medicine of the National Academies. Hepatitis and liver cancer: a national strategy for prevention and control of hepatitis B and C. Colvin HM and Mitchell AE, ed. Available at: http://www.iom.edu/Reports/2010/Hepatitis-and-Liver-Cancer-A-National-Strategy-for-Prevention-and-Control-of-Hepatitis-B-and-C.aspx. Updated January 11, 2010. Accessed March 21, 2011.
^x Pyenson B, Fitch K, Iwasaki K. Consequences of hepatitis C virus (HCV): Costs of a baby boomer epidemic of liver disease. Available at: http://www.natap.org/2009/HCV/051809_01.htm. Updated May 2009. Accessed March 21, 2011. This report was commissioned by Vertex Pharmaceuticals, Inc.
^xi Volk MI, Tocco R, Saini S, Lok, ASF. Public health impact of antiviral therapy for hepatitis C in the United States. Hepatology. 2009;50(6):1750-1755.
^xii Davis GL, Alter MJ, El-Serag H, Poynard T, Jennings LW. Aging of hepatitis C virus (HCV)-infected persons in the United States: A multiple cohort model of HCV prevalence and disease progression. Gastroenterology. 2010;138:513-521.

Vertex Pharmaceuticals Incorporated
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Source: Vertex Pharmaceuticals Incorporated

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