Peer-reviewed trial results demonstrate robust bacterial reduction without resistance in antibiotic-resistant Pseudomonas aeruginosa infections

BiomX Inc.,  a clinical-stage company developing natural and engineered bacteriophage therapies, has announced the publication of new data from its Phase 1b/2a trial of phage cocktail BX004 in the premier journal Nature Communications.

The peer-reviewed article, titled “Phage therapy with nebulized cocktail BX004-A for chronic Pseudomonas aeruginosa infections in cystic fibrosis: a randomized first-in-human trial,” reports previously unreported antimicrobial efficacy data confirming strong bacterial reductions in patients with antibiotic-resistant P. aeruginosa lung infections.

BX004 is designed to target chronic infections common in cystic fibrosis (CF) patients where antibiotic options are increasingly ineffective due to resistance.

Data from the Phase 1b/2a study showed that patients treated with BX004 achieved a bacterial reduction of approximately 2.7 log₁₀ compared to placebo — roughly a 500-fold decrease — with no emergent resistance and preservation of a healthy microbiome. This additional post hoc analysis is being reported for the first time.

The study also demonstrated a strong safety and tolerability profile for BX004, with no treatment-related adverse events. Phages were detected at the infection site throughout dosing and persisted up to one week post-treatment, supporting therapeutic durability.

Rotem Sorek, professor of genetics at the Weizmann Institute of Science, highlighted the study’s translational approach, combining large-scale genomic and computational methods to optimize bacteriophage design, broaden strain coverage, and reduce resistance risk.

BiomX has already initiated its Phase 2b trial of BX004, with topline results expected in Q1 2026.

Jonathan Solomon, CEO of BiomX, said: “Publication in a leading research journal validates our phage therapy platform and reinforces the potential to address significant unmet needs in chronic P. aeruginosa infections. We look forward to advancing BX004 development with the upcoming Phase 2b trial.”