5:22pm

Thu February 24, 2011
Shots - Health Blog

Pill That Hits A Cause Of Cystic Fibrosis Beats Expectations

More than 20 years after the gene behind cystic fibrosis was identified, a pill that could fix the problem in some people is getting closer to reality.

The experimental medicine, taken twice a day, goes by the code name VX-770. Now there are some promising results from a study in 161 people with a specific genetic mutation that affects about four percent of cystic fibrosis patients.

Lung function got 10 percentage points better, on average, in people who got the drug compared with those taking a placebo. The improvement at six months was still present almost a year after the study's start.

That much improvement is "a big deal for CF patients," Robert Beall, president of the Cystic Fibrosis Foundation told Shots. "It is larger than any other clinical intervention we've ever had in cystic fibrosis." Beall said there were no significant side effects.

The foundation has championed the development of drugs, including VX-770, and has provided $75 million to Vertex to get the medicine this far. If the drug makes it to market, the foundation will receive royalties from sales.

This pill, for people with the G551D mutation of the cystic fibrosis gene, helps a defective protein in cell membranes do a better job moving things around. Lisa Jarvis has more details on that at the Haystack blog. But a key takeaway is that the medicine gets at a root cause of cystic fibrosis in some people rather than just relieving their symptoms.

Now, to be perfectly clear, all we know about the latest data is from press releases. And the drug hasn't been submitted for review by the Food and Drug Administration, though Vertex expects to do that later this year.

But these results, even with plenty of caveats, suggest the drug is on the right track. Vertex's shares jumped 15 percent Wednesday as investors figured VX-770 looks even better than they'd expected.

"Wow!" wrote Dr. Mark Schoenebaum, a biotech and drug analyst ISI Group, in a note to investors. The effectiveness of VX-770 looks "best case," he wrote. Ultimately, the drug might be used by around 3,000 patients worldwide, if approved, and Schoenebaum expects it would be command a very high price, perhaps $250,000 a year. Copyright 2011 National Public Radio. To see more, visit http://www.npr.org/.