A Cystic Fibrosis Treatment Is Called ‘Game-Changing’

By REUTERS

Published: May 7, 2012

A combination of a cystic fibrosis drug and an experimental treatment for the disease, both developed by Vertex Pharmaceuticals, led to significantly improved breathing ability in a midstage study, the company said on Monday.

The data suggested that Vertex could have a multibillion-dollar franchise in treating cystic fibrosis, a life-threatening genetic disorder that affects about 70,000 people worldwide.

Stock in Vertex jumped 55 percent on Monday after the announcement, to $58.12 a share.

“This is very exciting data,” said Dr. Joseph Pilewski, adult cystic fibrosis physician at the University of Pittsburgh Medical Center.

“If this were to bear out in a Phase III pivotal trial it will dramatically impact the treatment options we have for patients with cystic fibrosis,” Dr. Pilewski said, cautioning that the data was preliminary and had not yet been fully analyzed. (Phase III pivotal trials are the last step before seeking approval.)

The drug, Kalydeco, helps only about 4 percent of cystic fibrosis patients with a specific gene mutation. In January, Kalydeco became the first approved drug to treat the underlying cause of the disease rather than symptoms.

Vertex is testing combinations it hopes will address the larger population of cystic fibrosis patients. The combination data disclosed Monday involves patients with genetic mutations that make up about half the population with the disease. Further data expected from the study could yield results meant to help an additional 30 percent.

The company is also testing Kalydeco as a monotherapy in patients as young as 2 1/2 years old and in patients with gene mutations not studied in its original pivotal trials. If results are encouraging, the use of Kalydeco could expand from 4 percent to 8 to 10 percent of patients worldwide, the company said.

Cystic fibrosis causes the thin layer of mucus that helps keep the lungs free of germs to become thick, clogging airways and leading to infections that damage the lungs. The average life expectancy for patients is 37 years, as damage to the lungs progresses, severely limiting their ability to breathe.

The interim analysis of the study looked at 37 patients who completed 56 days of treatment with the combination of Kalydeco and VX-809, and 11 patients who received a placebo. It found a statistically significant lung function improvement for those on the study drugs.

“These improvements were clinically very, very meaningful for these patients,” said Brian Skorney, an analyst with Brean Murray, Carret & Company. “This is really a game-changing combination therapy.”

An analyst at the ISI Group, Mark Schoenebaum, said Vertex could have a $4 billion franchise in cystic fibrosis. He called the data “excellent and much better than expected.”

Vertex officials said they would seek to start clinical trials to support approval for the combination at the end of the year or early next year.

“These data did exceed our expectations,” Vertex’s chief executive, Jeffrey Leiden, told analysts during a conference call. “They are leading us to accelerate 809 and Kalydeco into pivotal trials.”

In the data released on Monday, about 46 percent of patients who received the drugs experienced lung function improvement of five percentage points or more based on FEV1 — a measure of the maximum amount of air that can be exhaled in one second, Vertex said.

About 30 percent who received Kalydeco and VX-809 had a lung function improvement of at least 10 percentage points. None of the placebo patients achieved a 5 percent improvement from baseline to Day 56, the company said.

“The fact that it showed improvements in lung function in this small-sized trial I think is very impressive,” Mr. Skorney said.

The drugs were generally well tolerated with serious adverse events similar between the treatment and placebo groups, the company said. Complete data from the Phase II study are expected to be available in the middle of this year.