US health regulators released briefing documents Friday morning questioning the benefit of Vertex Pharmaceuticals’ combination therapy for cystic fibrosis patients.
Ahead of an advisory panel review, scheduled for Tuesday, May 12, US Food and Drug Administration (FDA) staff reviewers questioned one of the two drugs in the combination cystic fibrosis therapy. The combination includes Vertex’s already approved drug Kalydeco (ivacaftor) and investigational lumacaftor (VX-809).
The combination was compared to a placebo in patients aged 12 and over with a type of genetic mutation known as F508del, the most common cystic fibrosis-causing mutation. If the combination, known as Orkambi, is approved, roughly 8,500 patients will be eligible for the drug.
In the review, the agency said that the drug demonstrated a relatively small but statistically significant improvement in a key measure for lung function used to assess the drug. However, they said that the study did not prove that lumacaftor made a significant contribution to the outcome.
The agency said that comparing the data “raises the question whether lumacaftor contributes any added benefit over that of ivacaftor alone and begs the question if an invacaftor alone arm were included in the LUM/VA combination studies, would the treatment effects for ivacaftor alone also have been significant, especially in relation to improvements in lung functions and reductions in CF pulmonary exacerbations.”
However, analysts said that it is unlikely to block approval of the drug since Vertex has conducted Phase III studies demonstrating statistically significant, clinically meaning differences. The agency may require that Vertex conduct follow up studies. The FDA staff made no recommendation to the advisory committee on the drug’s application. The advisory panel will make a recommendation to the FDA prior to its scheduled decision date of July 5.
Source: US Food and Drug Administration
Last updated: 5/8/15; 4:25pm EST