Vertex Plans Additional Studies of Kalydeco™ (VX-770) in More CF Patient Groups

January 9, 2012

Vertex Pharmaceuticals Inc. announced yesterday it plans to begin clinical trials of the potential cystic fibrosis therapy Kalydeco™ (VX-770) in more patient groups later this year, including in children as young as 2 years old.

Kalydeco (kuh-LYE-deh-koh) is under review by the U.S. Food and Drug Administration (FDA) for approval in people ages 6 and older with the G551D mutation of CF.

The FDA has granted Vertex a six-month priority review of the drug, setting a target date of April 18 for the approval decision. If approved, Kalydeco would be the first drug available that targets the underlying cause of CF.

Vertex is planning clinical trials of Kalydeco in patient groups that were not evaluated in earlier Phase 3 studies of the drug, including:

  • Children ages 2 to 5 with gating mutations, including G551D.
  • People with other gating mutations besides G551D.
  • People with at least one copy of the R117H mutation of CF.

In gating mutations like G551D, the defective protein in CF moves to its proper place at the surface of the cell but does not function correctly. The CFTR protein instead acts like a locked gate, impeding the proper flow of salt and fluid in and out of the cell. Kalydeco aims to unlock that gate and help restore the function of the defective protein.

G551D is the most common gating mutation, accounting for about 4 percent of people with CF in the United States. The remaining gating mutations are found in about 1 percent of the CF population.

The R117H mutation, known as a “conductance mutation,” causes abnormal function of the CFTR protein at the cell surface. About 3 percent of people with CF in the United States have this mutation.

Kalydeco is also being tested in an ongoing Phase 2 trial in combination with another potential therapy, VX-809, in people with the most common mutation of CF, Delta F508. In addition, Vertex plans to launch a clinical trial in mid-2012 studying Kalydeco with another therapy in development, VX-661, in people with the Delta F508 mutation.

The CF Foundation worked with Vertex to discover Kalydeco, VX-809 and VX-661 and provided substantial financial and clinical support throughout the development process.

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