Vertex Pharmaceuticals has revealed highly impressive Phase III findings for its cystic fibrosis developmental drug – VX-770.
The results, which were found in patients with the rare mutation tied to cystic fibrosis – G551D, are expected to lead to approval in Europe by the end of 2011.
The Phase 3 STRIVE study of VX-770, an oral medicine in development that targets the defective protein that causes cystic fibrosis (CF), showed profound improvements in forced expiratory volume in one second (FEV1) through 24 weeks’ treatment that continued through to week 48 with VX-770 (n=83) treatment compared with placebo (n=78).
Significant improvements in all key secondary endpoints were also observed through week 48 among those who received VX-770.
Data from the study showed a significant, mean absolute improvement in lung function from baseline compared with placebo through week 24 of 10.6 percent among those treated with VX-770 (p<0.0001).
The equivalent improvement among those treated with VX-770 was 10.5 percent through week 48 (p<0.0001).
Highly statistically significant improvements in key secondary endpoints in this study were also reported through week 48.
Compared to those treated with placebo, people who received VX-770 were 55 percent less likely to experience a pulmonary exacerbation and, on average, gained nearly seven pounds (3.1kg) through 48 weeks.
There was a significant reduction in the amount of salt in the sweat (sweat chloride) among people treated with VX-770 in this study. Increased sweat chloride is a diagnostic hallmark of CF. Sweat chloride is a marker of CFTR protein dysfunction, which is the underlying molecular mechanism responsible for CF. People who received VX-770 also reported having fewer respiratory symptoms.
“Treating the underlying cause of cystic fibrosis with VX-770 led to clinical improvements that were far beyond our expectations, providing support for an entirely new approach to the treatment of this disease,” said Peter Mueller, Ph.D., Executive Vice President, Global Research and Development, and Chief Scientific Officer for Vertex.
“All primary and key secondary outcome measures in this study supported VX-770 over placebo.
“Patients’ lung function improved, they gained weight, experienced fewer respiratory symptoms and felt substantially better.
“Due to the significance of these data and the great need for new, more effective medicines, we will work with regulatory agencies to determine the fastest way to get VX-770 approved for people with this specific type of CF.”