GSK’s attempt to develop the first vaccine for herpes simplex virus (HSV) has ended in failure, leaving the race open for the likes of Moderna and BioNTech.
The recombinant protein vaccine, dubbed GSK3943104, failed to hit the primary efficacy endpoint of reducing episodes of recurrent genital herpes in the phase 2 portion of a phase 1/2 trial, GSK announced Wednesday morning. As a result, the British Big Pharma no longer plans to take the candidate into phase 3 development.
No safety concerns were observed in the study, according to GSK, which said it will continue to “generate follow-up data that could offer valuable insights into recurrent genital herpes.”
“Given the unmet medical need and burden associated with genital herpes, innovation in this area is still needed,” the company said. “GSK intends to evaluate the totality of all these data and other studies to progress future research and development of its HSV program.”
It's not the first time GSK’s efforts to prevent genital herpes have fizzled out. Back in 2010, the pharma abandoned its plans for Simplirix after the herpes simplex vaccine failed a phase 3 study.
Vaccines continue to be a major area of focus for GSK, which markets the shingles vaccine Shingrix and last year scored the first FDA approval for a respiratory syncytial virus vaccine in the form of Arexvy.
There are currently no approved vaccines for HSV, and GSK’s decision to halt work on GSK3943104 removes one of the leading contenders in the race to market. Other recent entrants come from the mRNA field, with Moderna having fully enrolled its 300-person phase 1/2 U.S. trial of its candidate, mRNA-1608, in herpes simplex virus type 2 (HSV-2) this year, while BioNTech dosed the first person in a phase 1 study of its own option, BNT163, at the end of 2022.
Explaining its decision to move into the HSV space, BioNTech pointed to the World Health Organization’s estimates of around 500 million people globally who are affected by genital infections caused by HSV-2, which can result in painful genital lesions, an increased risk for meningitis and high levels of emotional distress. HSV-2 infection also increases the risk of acquiring HIV infections by approximately threefold, the German biotech noted.