A month after the FDA lifted its clinical hold on GSK’s vaginal yeast infection drug Brexafemme (ibrexafungerp), the developer of the treatment, Scynexis, has resumed a phase 3 study in another use.
The dosing of the first new patient in the MARIO study triggers a $10 million milestone payment from GSK and another $20 million due in six months, the Jersey City-based biotech said in a May 28 press release.
GSK, for its part, is disputing the charges, according to Scynexis.
Two weeks ago, when Scynexis presented its first-quarter earnings, CEO David Angulo, M.D., said GSK did not want the trial to resume after it had been delayed for 19 months.
In its release this week, Scynexis said it's working with GSK to “resolve the disagreement."
“The rapid resumption of patient enrollment, just a few days after the investigational sites were re-activated in the study, reflects the eagerness of the scientific community to have new treatment options for this life-threatening infection,” Angulo said in a statement.
GSK reiterated its statement from two weeks ago on the dispute.
"We continue to work with Scynexis to commercialize Brexafemme," a company spokesperson said in an email. "With rates of resistance to other antifungal treatments rising, Brexafemme addresses a clear unmet need for new oral treatments and is an important asset of our growing anti-infectives portfolio."
The MARIO trial is investigating Brexafemme as a potential step-down antifungal treatment following intravenous echinocandin for invasive candidiasis, which Scynexis describes as a “life-threatening infection.”
“There is substantial need for new treatments for invasive candidiasis, particularly for Candida strains resistant to the currently approved antifungals,” Luis Ostrosky-Zeichner, M.D., a professor at UTHealth Houston, added in the release.
In 2021, the FDA approved Brexafemme for vulvovaginal candidiasis (VVC), which is more commonly known as a yeast infection. A year later, the FDA tacked on a second nod for Brexafemme to reduce the risk of recurrent VVC.
In 2023, GSK forged a partnership with financially strapped Scynexis, paying $90 million up front and agreeing to pay up to $503 million in potential milestones.
A few months later, trouble between the companies began when GSK found that the equipment used to produce Brexafemme was also used to manufacture a beta-lactam substance. Beta-lactam compounds can trigger allergic reactions in some individuals.
In September of 2023, the MARIO trial was put on hold shortly after Scynexis issued a voluntary recall of Brexafemme tablets due to the potential for cross-contamination.
When Brexafemme was originally approved, some analysts believed it had blockbuster potential. But entering the commercial realm was a challenge for Scynexis, which cut 40% of its staff in 2022.
After reporting sales of just $5 million for 2022, Scynexis struck the licensing deal with GSK in March 2023. Last year, GSK amended its deal with Scynexis, reducing the potential milestone payments.