GSK Completes Acquisition of Affinivax, Inc.

GSK plc (LSE/NYSE: GSK) today announced it has completed the acquisition of Affinivax, Inc (Affinivax), a clinical-stage biopharmaceutical company based in Cambridge (Boston, Massachusetts). Affinivax has pioneered the development of a novel class of vaccines, the most advanced of which are next-generation pneumococcal vaccines.

As previously announced, the acquisition of Affinivax aligns with GSK’s strategy of building a strong portfolio of specialty medicines and vaccines. It includes a next-generation 24-valent pneumococcal vaccine candidate (AFX3772), currently in phase II development, which is based on the highly innovative Multiple Antigen Presenting System (MAPS^TM) platform technology. A 30-plus valent pneumococcal candidate vaccine is also in pre-clinical development.

The MAPS^TM technology supports higher valency than conventional conjugation technologies, potentially enabling broader coverage against prevalent pneumococcal serotypes and generating higher antibody responses against many individual serotypes than current pneumococcal vaccines.

Tony Wood, Chief Scientific Officer, GSK, said: “Affinivax’s exciting pneumococcal vaccine candidates, the potentially disruptive MAPs technology and their fantastic scientific talent, further strengthen our pipeline of novel vaccines and presence in the Boston area”.

In the adult phase I/II clinical trials, AFX3772 was well tolerated in participants and demonstrated good immune responses compared to the current standard of care. In July 2021, the US Food and Drug Administration granted Breakthrough Therapy designation for AFX3772 to prevent S. pneumoniae invasive disease and pneumonia in adults 50 years and above. Preparations for the start of the phase III program are underway. Phase II clinical trials started in June 2022 to assess the use of the vaccine in the paediatric population.