PASA16

**PASA16** is a lytic bacteriophage of the *Pbunavirus* genus isolated from soil, specifically targeting *Pseudomonas aeruginosa* strains, including those forming protective biofilms and resistant to antibiotics. It exhibits high lytic activity due to a notable lysozyme-like endolysin gene, enabling it to lyse susceptible bacterial cells. Developed by Adaptive Phage Therapeutics, PASA16 has shown an 86.6% favorable clinical outcome rate (13/15 patients) in a compassionate use case series for refractory *P. aeruginosa* infections, primarily osteoarticular and foreign device-associated, when combined with antibiotics after in vitro susceptibility confirmation. Treatment durations ranged from 8 days to 6 weeks (mostly ~2 weeks), administered 1-2 times daily via intravenous, local, or topical routes, with only minor, manageable side effects like transient liver enzyme elevation or leukopenia.