FDA slaps a hold on Gilead's injectable HIV treatment over concerns about potential glass contaminants
The FDA is coming down on yet another therapy over concerns about glass particulates winding up in drug solution.
Regulators have slapped a clinical hold on 10 trials studying injectable versions of Gilead’s experimental HIV treatment lenacapavir, due to concerns that vials made of borosilicate glass could lead to the formation of sub-visible glass particles in the solution.
“We are committed to working diligently with FDA to resolve this glass vial compatibility quality issue and resume injectable lenacapavir dosing in the affected studies in a timely fashion,” CMO Merdad Parsey said in a statement.
The dosing of oral formulations will continue, according to Gilead, and investigators will continue monitoring the patients who have already been dosed with injectable formulations, as well as dose participants in comparator arms.
Gilead’s been working on lenacapavir, an HIV-1 capsid inhibitor, for both the treatment and prevention of HIV-1 infection. While most antivirals act on just one stage of viral replication, the company says lenacapavir is designed to inhibit HIV-1 at multiple stages of its lifecycle.
The drug is Gilead’s big next-gen antiviral. Back in March, the company signed a co-development pact to study the candidate in combination with Merck’s islatravir.
However, Merck slammed the brakes on its program in November after investigators flagged a drop in immune cell counts that an external committee determined was related to islatravir. The FDA placed an official clinical hold on the experimental treatment earlier this month.
The clinical hold affects several mid- and late-stage trials, including one Phase III assessing pre-exposure prophylaxis in cisgender men, transgender women, transgender men, and gender non-binary people 16 years or older; and another Phase III looking at pre-exposure prophylaxis in adolescent girls and young women in combination with standards of care emtricitabine/tenofovir alafenamide.
This isn’t the first time Gilead has run into trouble with glass particulates. Earlier this month, the pharma company recalled two lots of its Covid-19 treatment Veklury after the appearance of particulates. A customer complaint had been confirmed by a Gilead investigation.
Over the last year, glass particulates have emerged as an industry-wide problem. Back in October, one lot of Merck’s antibiotic Cubicin was recalled after a piece of glass was found in a vial, raising safety concerns. And in June, the FDA issued a warning letter to the Japanese manufacturer Toyobo Co after 12 batches of injectables were found to have cellulose and glass fibers, stains, and particles on vials, the FDA said.
This month, the FDA released draft guidance aiming to help drugmakers prevent the risk of particulate contamination.
While side effects caused by the glass pieces depend on the route of administration, the patient population, and the nature of the particulates themselves (such as size or shape), the agency noted that some patients could experience infection, venous or arterial blood clots, inflammation, or even emboli, abscesses, and granulomas in visceral organs.