Aridis stock surges ~35% as lung disease drug AR-501 meets main goal in mid-stage study

Aridis Pharmaceuticals (NASDAQ:ARDS) inhaled drug AR-501 met its main and secondary goals of safety and pharmacokinetics in a phase 2a trial to treat patients with cystic fibrosis (CF) who have confirmed Pseudomonas aeruginosa bacterial and other potential infections.

The study enrolled 42 adults.

Aridis said three weekly doses of AR-501 — an inhaled formulation of gallium citrate administered as a liquid aerosol — at 6.4mg, 20mg, and 40mg dose were well tolerated in the patients.

The company said no drug related serious adverse events (SAEs) were seen. The majority of treatment emergent adverse events (TEAEs) were respiratory in nature and mostly mild to moderate in severity

The patients achieved high uptake of AR-501 in the respiratory tract, as measured by sputum concentrations, at levels which were more than 50-fold higher than required for inhibiting the bacteria P. aeruginosa, according to the company.

Aridis noted that inhaled delivery saw more than 10-fold higher respiratory uptake of gallium (AR-501) than past clinical studies of intravenous (IV) gallium that led to improvement in lung function and reduction in P. aeruginosa.

"The high drug level achieved in the lungs along with low systemic exposure from inhaled delivery effectively overcome the limitations of conventional intravenous delivery, and provide a strong basis for a large efficacy study in CF and other lung infections," said Aridis' Chief Medical Officer Hasan Jafri.

The company said that due to the heterogeneity of concurrent medicine use in the trial, exploratory goals such as microbiological burden of P. aeruginosa and lung function, were not established in the trial.

ARDS +37.14% to $0.63 premarket March 13