Arixa Pharmaceuticals, a company developing next-generation oral antibiotics for drug-resistant Gram-negative infections announced that Pfizer’s Hospital Business has agreed to acquire Arixa.

Arixa’s lead compound, ARX-1796, is an oral prodrug of avibactam, a beta lactamase inhibitor (BLI) that was FDA-approved in 2015 as part of Avycaz (sold by Pfizer as Zaficefta outside the US), an intravenous-only combination with ceftazidime for the treatment of a number of indications caused by Gram-negative pathogens.

Dr Eric M Gordon, Arixa Co-Founder and CSO, led a team to address the challenge of creating a viable prodrug of avibactam with now-patented chemistry. As a result of Arixa’s now patented chemistry, the prodrug of avibactam was 60-80 per cent absorbed when administered orally to humans in a Phase 1 clinical trial, releasing the FDA-approved avibactam molecule in the bloodstream. In contrast, ~7 per cent of the intravenous compound is absorbed orally. Combined with an antibiotic such as ceftibuten, Arixa’s ARX-1796, if approved, opens the way for orally-available avibactam to be part of a next-generation, oral antibiotic combination for resistant urinary tract and other infections.

Financial terms of this acquisition were not disclosed.

Four Oaks Partners advised Arixa in connection with this transaction.