Inspire Pharmaceuticals Inc, Raleigh, NC, announced yesterday that top-line results from its second phase 3 clinical trial, TIGER-2, of denufosol did not demonstrate statistical significance for its primary efficacy endpoint, which was change from baseline FEV1 at the week-48 endpoint (48 weeks or last observation carried forward).
“These TIGER-2 results were disappointing and unexpected given the treatment effect observed in the TIGER-1 trial,” said Adrian Adams, president and CEO of Inspire. “We will conduct a thorough analysis of the data to fully understand the results from this trial and the impact on any future development of denufosol and on the Company going forward.”
Patients receiving denufosol in the 466-patient, double-blind, placebo-controlled clinical trial had an improvement of 40 mL, compared to 32 mL for the patients receiving placebo (p=0.742).
There were no statistically significant differences between denufosol and placebo for three key secondary endpoints, which were:
- Rate of change in percent predicted FEV1 over 48 weeks, a measure of lung function adjusted for a patient’s predicted normal based on height, weight, and gender (-2.30% for denufosol and -3.02% for placebo; p=0.410);
- Change from baseline in FEF25%-75% at the week 48 endpoint, a measure of small airways function (-0.034 L/sec for denufosol, -0.018 L/sec for placebo; p=0.728); and
- Time to first pulmonary exacerbation, as defined by treatment with IV antibiotics for at least one respiratory sign or symptom (p=0.132).
According to the Cystic Fibrosis Foundation, which had closely followed the trial, if the results had been positive, the data would have served as a basis for a New Drug Application to the US Food and Drug Administration.
“This is a serious disappointment to the entire CF community,” said Robert J. Beall, PhD, president and CEO of the Cystic Fibrosis Foundation. “We have long understood that drug development is not predictable, but we are always hopeful that promising therapies will prove effective for those with CF. Inspire’s latest data underscores the importance of our pursuing multiple new therapies that can control and cure CF.”
Source: Inspire Pharmaceuticals; Cystic Fibrosis Foundation