BiomX Inc. has announced positive data from its Phase 1b/2a clinical trial of BX004, a novel phage cocktail, for treating cystic fibrosis (CF) patients with chronic Pseudomonas aeruginosa pulmonary infections. The study, a randomized, double-blind, placebo-controlled trial, demonstrated favorable safety and notable microbiologic and clinical efficacy, including in patients on standard of care treatment with elexacaftor/tezacaftor/ivacaftor (ETI). These findings were presented at the European Respiratory Society (ERS) Congress and the North American Cystic Fibrosis Conference, marking significant steps forward in addressing this challenging aspect of CF management.
The investigational drug, BX004, is a fixed multi-phage cocktail designed to target and destroy P. aeruginosa, a bacterium that significantly contributes to morbidity and mortality in CF patients. The Phase 1b/2a trial was a two-part study assessing the safety and efficacy of BX004-A.
Microbiological and Clinical Efficacy
In the first part of the study, subjects receiving BX004-A showed a greater reduction in P. aeruginosa colony-forming units (CFU)/g of sputum at day 15 compared to baseline, versus placebo. In the second part, a notable 14% of subjects receiving BX004-A had a negative P. aeruginosa sputum culture on day 10 (end of treatment), compared to 0% in the placebo group. This suggests a potential for BX004 to eradicate the bacteria in some patients.
Improvement in Lung Function
Lung function, as measured by forced expiratory volume in 1 second (FEV1), increased by 5.66% in subjects receiving the phage cocktail compared to a decrease of 3.23% in the placebo group. This improvement was particularly pronounced in a subgroup of patients on continuous inhaled antibiotics, those on ETI, and those with lower lung function (FEV1 <70%).
Safety and Tolerability
The trial also highlighted the favorable safety profile of BX004-A. Phage was detected in the sputum of all BX004-A subjects, with no treatment-related phage resistance observed and no serious adverse events reported during therapy.
Next Steps for BX004
BiomX is planning to initiate a randomized, double-blind, placebo-controlled, multi-center Phase 2b trial in CF patients with chronic P. aeruginosa pulmonary infections. The trial aims to enroll approximately 60 patients randomized at a 2:1 ratio to BX004 or placebo. The treatment will be administered via inhalation twice daily for 8 weeks. The trial is designed to monitor the safety and tolerability of BX004, demonstrate improvement in microbiological reduction of P. aeruginosa burden, and evaluate effects on clinical parameters such as lung function (FEV1) and patient-reported outcomes. Results from this Phase 2b trial are expected in the third quarter of 2025. The U.S. Food and Drug Administration (FDA) has granted BX004 Fast Track designation and Orphan Drug Designation, underscoring the urgent need for new treatments in this patient population.
Jonathan Solomon, BiomX Chief Executive Officer, commented, "Our Phase 1b/2a trial continues to garner strong support among the scientific community... We look forward to connecting with the strong CF community of researchers, advocates and patients at the event, and to discussing these findings and our path forward in more detail."
