Armata Pharmaceuticals has announced positive topline results from its phase 1b/2a SWARM-P.a. trial assessing the safety, tolerability, pharmacokinetics, and pharmacodynamics of AP-PA02 for the treatment of chronic pulmonary Pseudomonas aeruginosa infections in patients with cystic fibrosis (CF).

“We are pleased to present topline data for our lead multiphage candidate, AP-PA02, which was evaluated in cystic fibrosis patients in the SWARM-P.a. clinical trial, and to announce the dosing of the first subject in our Tailwind study of AP-PA02 in [noncystic fibrosis bronchiectasis (NCFB)],” said Mina Pastagia, MD, MS, chief medical officer at Armata, in a press release.

“The data from our SWARM-P.a. study gives us confidence that the pharmacokinetics of inhaled phage are predictable and suggest that optimized exposures will correlate with bacterial load reduction.”

The results of SWARM-P.a.—a multicenter, randomized, double-blind, placebo-controlled, single- and multiple-ascending dose study—showed that inhaled AP-PA02 was effectively delivered to the lungs with minimal systemic exposure. Single- and multiple-ascending doses resulted in a proportional increase in treatment exposure.

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The investigators observed a trend toward an improvement in bacterial load reduction for participants receiving AP-PA02 as compared to placebo. For participants with the highest average exposure of susceptible phage, the durability was an approximately 2-log reduction from the end of treatment to the end of the study (day 28 postdose).

Moreover, the results suggest significant microbiological impacts in the participants with the highest exposures.

AP-PA02 was well-tolerated, with only mild, self-limited adverse events being reported in a few participants. The treatment-emergent adverse event profile of AP-PA02 was similar to that of placebo.


Armata Pharmaceuticals announces positive topline data from phase 1b/2a SWARM-P.a. clinical trial of inhaled AP-PA02 in patients with cystic fibrosis. News release. Armata Pharmaceuticals, Inc; March 6, 2023.