GSK axes vaccine from $2.1B deal, switching to preclinical successor over 'increased competition'

GSK has stopped (PDF) development of one of the lead programs from its $2.1 billion Affinivax takeover, axing a phase 2 pneumococcal 24-valent vaccine candidate for adults in favor of a preclinical 30-plus valent shot. A spokesperson for GSK said “increased competition” drove the decision.

When GSK bought Affinivax in 2022, the 24-valent pneumococcal candidate featured prominently in its statement about the takeover. The candidate had already delivered phase 1/2 results in adults, and GSK said phase 3 was expected “to start in the short term.” More than two years later, GSK has stopped work on the 24-valent candidate in adults to prioritize and accelerate development of a 30-plus shot.

The spokesperson said GSK is confident Affinivax’s Multiple Antigen Presenting System has best-in-class potential “to commercially deliver at scale pneumococcal vaccines with disease coverage over 90% while maintaining high level of immunogenicity.” However, because of increased competition, GSK is focusing on its preclinical 30-plus shot in adults. A 24-valent program in children is continuing through phase 2.

GSK’s decision follows the publication of phase 1/2 results for Vaxcyte’s 31-valent pneumococcal vaccine candidate. Analysts hailed Vaxcyte’s data as “stunning.” GSK is aiming to move the 30-plus candidate into the clinic in 2025. Pfizer has (PDF) a 25-valent vaccine candidate in phase 2 and a 30-plus valent program in preclinical.

The pneumococcal vaccine candidate was one of three infectious disease prospects that GSK removed from its phase 2 pipeline as part of its third-quarter update. GSK axed its Neisseria gonorrhoeae vaccine candidate after seeing interim data from a phase 2 trial. The spokesperson said the “candidate did not meet our pre-defined efficacy criteria” and won’t advance into phase 3. No safety concerns were seen.

GSK also confirmed it ended development of GSK3943104 in the suppression of recurrent genital herpes in adults. The company reported the failure of a phase 1/2 trial of the therapeutic vaccine in September. At the time, GSK said it wouldn’t take the vaccine into phase 3 but would keep evaluating the data.

The only discontinuation outside of infectious disease was osteoarthritis pain prospect GSK3858279. The GSK spokesperson confirmed the company is stopping development of the anti-CCL17 antibody without providing an explanation for the action. GSK recently reached primary competition of a phase 2 study of the candidate in the setting. Another trial is testing the antibody in diabetic peripheral neuropathic pain.

While GSK cut programs in the quarter, CEO Emma Walmsley hailed the progress of the wider pipeline on a call with the media Wednesday. Walmsley said the progress includes 11 positive phase 3 readouts this year that have paved the way for “five major launches next year.”