GSK manufacturing review prompts Scynexis to pull Brexafemme, halt trials over contamination concerns

When Scynexis won FDA approval for its antifungal drug ibrexafungerp back in 2021, some analysts predicted the drug could eventually surpass the $1 billion annual sales threshold. But now the drug's launch is taking a serious detour.

After layoffs, an R&D pivot by the company and a licensing deal with pharma giant GSK, the drug is temporarily being pulled from the market.

Monday, Scynexis said in a filing (PDF) that a recent review of the drug's manufacturing process by GSK has triggered a recall of the product and a pause of all clinical trials testing the medicine.  

As part of GSK's review, Scynexis learned of potential cross-contamination risks during the manufacturing process of ibrexafungerp, which is marketed as Brexafemme.

The company is not aware that any of its medicine has been contaminated. Scynexis said it has not received adverse event reports tied to contamination.

But because of the contamination risk and "out of an abundance of caution," Scynexis is pulling the drug and pausing clinical studies "until a mitigation strategy and a resupply plan are determined."

It's the latest unfortunate turn for the company after Brexafemme's 2021 approval for the treatment of vulvovaginal candidiasis prompted analysts to place lofty sales targets on the medicine.

About a year after the FDA approval, Scynexis said it would cut about 40% of staff and pursue a licensing deal for the medicine. At the time of that announcement, Scynexis said it would cease promotions for the medicine and revealed changes to its executive roster.

Then in March, GSK entered the fray with a $90 million deal to market the antifungal. In addition to the upfront payment, GSK pledged up to $503 million if the drug met certain milestones.

At the time of the licensing deal, GSK's chief commercial officer Luke Miels said the company believed it could leverage its commercial clout to grow the drug to more than $500 million in annual sales.

In a statement to Reuters, a GSK spokesperson said the company is "continuing to evaluate the situation." Guggenheim analysts believe it will take "several months" for Scynexis to resolve the situation, according to the news service.