The trial was designed to evaluate patients age 12 and up who carry at least one copy of a CF mutation called G551D. The study included 161 patients who received at least one dose of VX-770 or placebo.

Patients who took the drug, compared to those on placebo, showed a marked improvement in lung function at 24 weeks, which was sustained for the duration of the 48-week trial.

Patients also showed improvement across all key secondary endpoints in the study, including reduced likelihood of experiencing a pulmonary exacerbation, decreased respiratory symptoms and improved weight gain. Each of these areas is critically important to the health of people with CF.

In addition, average sweat chloride levels of patients on VX-770 dropped toward normal levels, while those on placebo did not change - indicating the drug is impacting the underlying defect in CF. Excessive sweat chloride (salt) is a key clinical indicator of CF.

VX-770 is being developed by Vertex, and was discovered in collaboration with the CF Foundation, which provided substantial support to Vertex throughout the development process, including an approximately $75 million investment.

About four percent of people with CF carry the G551D mutation. More studies are needed to determine whether other CF mutations may benefit from VX-770.

“These results are highly encouraging. They provide scientific evidence that support our long-standing belief that targeting the underlying defect of CF may have a profound effect on the disease,” said Robert J. Beall, Ph.D., president and CEO of the Cystic Fibrosis Foundation. “We have much more to do to end the suffering caused by this disease, but these data are extremely exciting, especially for people with the G551D mutation and their families. The results also offer significant hope that a similar approach to treatment may help the majority of patients living with CF.”

The Phase 3 data support Vertex's plan to submit a New Drug Application for VX-770 to the U.S. Food and Drug Administration (FDA) in the second half of 2011. Generally, the FDA takes between 6 and 12 months to review and rule on a drug application.

“The Cystic Fibrosis Foundation has played an instrumental role in our more than 10-year effort to discover and develop potential new CF medicines such as VX-770,” said Matthew W. Emmens, chairman, president and CEO of Vertex. “The data announced today reflect a significant investment of time, dollars and scientific expertise from both Vertex and the CF Foundation, and we look forward to working closely with the Foundation as we seek to bring VX-770 to people with CF.”

Said Preston W. Campbell III, M.D., executive vice president for medical affairs of the Cystic Fibrosis Foundation: “As a physician who has treated CF patients for many years, the VX-770 results are more than just numbers - they represent hope.” He added, “It's not surprising that patients felt better on the drug because of the magnitude of lung function improvement and weight gain. These are important clinical outcomes, and the fact they were maintained through 48 weeks is very encouraging.”

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