Vertex Unveils Exciting Data for Cystic Fibrosis Drug
Feb24

Vertex Unveils Exciting Data for Cystic Fibrosis Drug

In one of those rare cases of good science translating directly into good medicine, Vertex Pharmaceuticals yesterday unveiled positive results from a Phase III trial of VX-770, a small molecule that treats the underlying defect of cystic fibrosis. The data “are very fresh, but nonetheless unambiguous and stunningly clear,” Vertex’s CSO Peter Mueller told analysts on a call yesterday. Further, they clear the way for Vertex to file for regulatory approval for VX-770 in the U.S. and Europe in the second half of this year. Before we get into the details of that data, a quick review of cystic fibrosis. As we described back in 2008, folks with CF have a mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which carries the recipe for making a protein that shuttles chloride ions from one side of a cell membrane to the other. That faulty gene means that people with CF absorb too much salt and have a hard time secreting it. Without the right balance of hydration, their lungs become dotted with dried-out pockets that get clogged with thick mucus, an environment ripe for bacteria growth. Patients suffer from chronic infections, often with the most pernicious of bugs, and take a panoply of antibiotics and other treatments to manage the symptoms of their disease. Vertex’s drug is generating excitement because it addresses the underlying cause of the disease. Think of CFTR as a gate that allows chloride ions out of the cell. Depending on the mutation that causes a patient’s CF—there are a handful of genetic malfunctions—that gate might be rusty, and not opening right, or, more commonly, there simply aren’t enough gates. VX-770 is being tested in people with a mutation akin to the former, and works to increase the flow of chloride ions through the gate, thereby restoring the right level of hydration in the lungs. In the Phase III trial of 161 people, the drug clearly met its primary endpoint of improving lung function. After 48 weeks on the drug, there was a relative improvement in lung function of 16.9% compared to placebo, and the absolute improvement (calculated by dividing the relative improvement by the baseline lung function)  of 10.6%. “This improvement in lung function both on an absolute and relative basis is particularly significant since it came on top of the other therapies patients continue to receive,” Vertex’s chief medical officer Robert Kauffman said yesterday. One of the most striking pieces of information gathered in this trial was the effect on the rate of pulmonary exacerbations, or periods when their disease worsens, Kauffman said. While the ability to improve lung function is critical, for...

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Vertex Unveils Positive Telaprevir Data
May25

Vertex Unveils Positive Telaprevir Data

Ending months of anticipation, Vertex Pharmaceuticals unveiled the first set of data from a Phase III trial of telaprevir, a protease inhibitor for the treatment of hepatitis C. The company is expected to submit for regulatory approval later this year, and launch the drug in 2011. Vertex said that 75% of genotype-1 patients—viewed as the toughest to treat--who received 12 weeks of telaprevir treatment on top of the current standard of care (48 weeks of pegylated interferon and ribavirin) were cured of the infection. Only 44% of patients in the control arm, which received only the standard of care, were cured after 48 weeks. Leerink Swann analyst Seamus Fernandez told investors the results set an "impressively high bar" for treatment in HCV. Importantly, adding the drug to the standard of care will lessen the total treatment time for many HCV patients. In addition to not being very effective, many people can’t tolerate the harsh side effects associated with interferon and ribavirin. Physicians liken the 48-week regimen to living with a nasty flu for a year. In hopes of halving the number of weeks on interferon and ribavirin, Vertex conducted what is called a “response-guided trial.” If the virus was sufficiently quelled after four weeks with the telaprevir addition, patients went on to receive just 24 weeks total of therapy. The company said “the majority” of patients received just 24 weeks of treatment. That 24-week figure is a critical one. Merck is hot on Vertex’s heels with its own protease inhibitor, boceprevir. Both companies are expected to launch their drugs next year, and with similarly mild safety issues, analysts say the drug that can shut down the disease the quickest will win. Merck is also conducting a response-guided study and at its R&D day said a retrospective look at its Phase II data suggests patients can be successfully treated in 24 weeks with boceprevir. BMO Capital Markets analyst Jason Zhang was dead on with his estimates for the drug. As we wrote earlier this month: Zhang expected the Phase III data to show a sustained viral response (the equivalent of a cure) of 75% of patients receiving telaprevir. His guess for telaprevir’s biggest competitor, Merck’s boceprevir? 74% sustained viral response. We’ll have to wait and see how close he comes on that figure, as Merck has been vague about when its Phase III results will be released. The big pharma firm has only said that it expects to present the data at an upcoming conference. My guess? We will likely be waiting for the American Association of Liver Disease’s annual shindig, also known as “The Liver Meeting,” in October. For...

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