In a strategic shift, GSK has halted the development of its 24-valent pneumococcal vaccine for adults—a major project from its $2.1 billion acquisition of Affinivax. Instead, GSK has chosen to prioritize a more advanced preclinical candidate targeting over 30 pneumococcal strains. According to a GSK spokesperson, the decision was driven by the increasingly competitive landscape in the pneumococcal vaccine sector.
When GSK acquired Affinivax in 2022, the 24-valent vaccine was touted as a central asset, with plans to enter Phase 3 trials “in the short term.” However, as competition intensifies, GSK is fast-tracking its preclinical 30-plus valency shot, with ambitions to advance it to clinical trials by 2025. The 24-valent vaccine program remains active in pediatric studies, currently progressing through Phase 2.
Affinivax’s Multiple Antigen Presenting System (MAPS) is seen as a differentiator in this crowded space. GSK maintains confidence in MAPS, emphasizing its potential to cover over 90% of pneumococcal disease strains while delivering high immunogenicity. However, rival Vaxcyte’s recent release of Phase 1/2 data for its own 31-valent pneumococcal vaccine candidate, praised by analysts, likely influenced GSK’s pivot to a higher-valent candidate.
In addition to the pneumococcal program shift, GSK announced it is discontinuing two other infectious disease initiatives: a vaccine targeting Neisseria gonorrhoeae following underwhelming Phase 2 efficacy data, and GSK3943104, a candidate aimed at preventing recurrent genital herpes in adults, after its Phase 1/2 trial failed to meet expectations. Both programs were cut during GSK’s third-quarter review, though no safety issues were reported.
Outside of infectious disease, GSK also scrapped a Phase 2 osteoarthritis pain treatment, GSK3858279, which targeted the CCL17 antibody. No reason was provided, though the candidate was nearing the end of a Phase 2 study in osteoarthritis and being tested in diabetic neuropathic pain.
Despite the strategic realignments, GSK CEO Emma Walmsley expressed optimism, highlighting 11 successful Phase 3 readouts in 2023. These advancements, she noted, pave the way for “five major launches next year.”
