British drugmaker GSK has signed an exclusive agreement with US-based biotechnology company Scynexis to license the latter’s antifungal therapy Brexafemme (ibrexafungerp tablets).

Brexafemme is a novel oral glucan synthase inhibitor that works with a distinct mechanism of action, where it kills the fungus, while some antifungals only inhibit the fungal growth.

The drug has been approved by the US Food and Drug Administration (FDA) to treat vulvovaginal candidiasis (VVC) and reduce the incidence of recurrent VVC (RVVC).

Currently, ibrexafungerp is being developed in Phase 3 clinical trials for the potential treatment of invasive candidiasis (IC), a life-threatening fungal infection.

It is said to be the only US FDA-approved oral antifungal for the treatment of VVC and reduction of RVVC.

GSK chief commercial officer Luke Miels said: “The challenge of antimicrobial resistance includes increasing rates of multi-drug resistant fungal infections.

“Brexafemme is a novel, approved antifungal medicine with a broad spectrum of activity against existing and emerging resistant strains of fungi. In addition, the transaction consolidates GSK’s synergistic portfolio of innovative late-stage antibiotics.”

Under the terms of the agreement, GSK will obtain rights to commercialise Brexafemme for VVC and RVVC, in exchange for an upfront payment of $90m and potential milestone-based payments of $503m.

Scynexis is eligible to receive up to $245.5m in specific development, regulatory, and commercial milestones related to IC indications that are completed.

Also, the US drugmaker may receive an additional $15m in milestone payment, based on successful US FDA approval of an additional indication.

The British drug maker will also pay sales-related milestone payments of up to $242.5m, and tiered royalties on the sales across all indications.

It will also receive an exclusive licence to develop ibrexafungerp and commercialise Brexafemme in all countries except the greater China region and certain other countries.

Scynexis retains rights to all other assets derived from enfumafungin and can execute the Phase 3 programme for IC and other ongoing trials.

Scynexis president and chief executive officer David Angulo said: “This agreement represents a major milestone for Scynexis, maximising Brexafemme’s commercial potential in VVC and further validating our vision of the critical role for this first-in-class antifungal in invasive infections.

“We are thrilled to partner with GSK on this high-potential asset and will continue progressing ibrexafungerp’s phase III programme in invasive candidiasis (IC).”