Cidara Therapeutics has overcome the uncertainties raised by the FDA’s advisory committee to receive near-unanimous backing for its antifungal drug, boosting the prospects of the therapy winning approval in March.
The candidate, rezafungin, is a once-weekly treatment for invasive Candida infections. Cidara, which has licensed the product to Melinta Therapeutics, presented clinical trial data showing non-inferiority to the current once-daily standard of care caspofungin. Despite noting limitations of the data, the advisory committee voted 14 to one that rezafungin has a favorable risk-benefit profile in a particular context.
“This is a very difficult situation because of the wide confidence intervals,” Sally Hunsberger, Ph.D., an NIH statistician and member of the advisory committee, said at the meeting. “The truth is that ... [rezafungin] could be 14% worse. That's on the table. Do we feel comfortable giving a treatment that could be 14% less [efficacious]?”
Hunsberger and 13 other members of the advisory committee ultimately decided that rezafungin has a favorable risk-benefit profile in the treatment of invasive candidiasis in adults with limited or no other options. The lack of access to existing treatments went in Cidara’s favor, as Sankar Swaminathan, M.D., a professor at the University of Utah School of Medicine, told the advisory committee.
“We often have a great deal of difficulty treating patients once they leave the hospital. It often boils down to insurance coverage, just almost silly things like patients don't have insurance to get IV setups at home. It makes it very, very difficult to give once-daily candidates,” Swaminathan said. As a once-weekly medicine, rezafungin could clear some of the barriers to treatment identified by Swaminathan.
Joan Hilton, a biostatistics professor, at the University of California, San Francisco, was the lone no vote. While the other members of the panel found reasons to overlook the limitations of the data, Hilton saw a dataset that falls short of the approval standards set by the FDA.
“Do we have adequate data collectively across all studies to approve this? I'm extremely uncomfortable with the idea,” Hilton said. “I don't think the full body of the evidence meets the clinical trials approval criteria set out in the FDA documents. In particular, I do not think that a pooled analysis makes sense when you don't specify that that analysis will be pooled until after you know what the results are.”
Shares in Cidara climbed 9% in early morning trading Wednesday to $1.01 in the wake of the positive vote, compared to 92 cents at close the previous day. If rezafungin is approved, Melinta will be responsible for commercialization. The deal is worth $60 million in regulatory milestones to Cidara.