The European Commission has become the first regulator worldwide to approve Gilead Sciences’ Sunlenca (lenacapavir) — the only twice-yearly add-on drug for people living with multidrug-resistant HIV.

Sunlenca is a first-in-class capsid inhibitor with a multi-stage mechanism of action and has no known cross-resistance to other existing drug classes. The drug, used in combination with other antivirals, will offer a new treatment option in an area with critical unmet needs — people with HIV whose virus no longer effectively responds to their current therapy.

The U.S. FDA rejected Gilead’s NDA for Sunlenca back in March. In the complete response letter, the FDA said its decision to reject the candidate was due to CMC issues with the glass vials the drug was intended to be distributed. Specifically, the agency raised questions about vials made of borosilicate glass and their compatibility with lenacapavir solution.

But the FDA accepted Gilead’s resubmission last month and gave the drug a PDUFA action date of December 27, 2022.

Once launched, Sunlenca will compete with ViiV Healthcare’s Rukobia, approved in both the U.S. and Europe, which is taken twice daily by mouth.