gorodenkoff
Aridis Pharmaceuticals (NASDAQ:ARDS) AR-301 monoclonal antibody therapy failed the primary endpoint in a phase 3 trial to treat ventilator-associated pneumonia (VAP) caused by the gram-positive bacterium Staphylococcus aureus (S. aureus).
The study, called AR-301-002, evaluated the superiority of the complementary use of AR-301 with the standard of (SOC) antibiotics versus SOC antibiotics alone.
The study enrolled 174 mechanically ventilated intensive care unit (ICU) patients who likely had pneumonia caused by S.aureus, with 120 patients who finally met the criteria. According to Aridis, the target sample size was 240, which was affected by the pandemic and the conflict in Eastern Europe.
The company said that statistical significance was not reached for the primary endpoint of clinical cure rate at day 21 compared to antibiotics alone. Clinical cure at day 21 was 68.9% (42/61 patients) for AR-301 + SOC, compared to 57.6% (34/59) for SOC alone.
In adults 65 years and older, absolute efficacy (improvement in clinical cure rate) increased to 34% on day 21 and 38% on day 28. The increase in absolute efficacy was primarily due to lower efficacy of SOC antibiotics in adults 65 years and older compared with adults younger than 65 years (30% vs. 75%, respectively), the company added.
According to Aridis, in patients with methicillin-resistant S. aureus (MRSA), the absolute efficacy was 28% greater than SOC alone.
The company noted that AR-301 was associated with decreasing trends in key secondary outcomes, including measures of length of stay (median 19 vs 28 days), ICU time (median 13 vs 20 days) and days mechanical ventilation (median 6 vs 8 days).
All-cause mortality rates in all patients were: AR-301: 23.6% (21/89) vs. SOC: 18.8% (16/85). These deaths were primarily related to the patients’ underlying conditions, according to the company.
Aridis said that the intravenous (IV) infusion of AR-301 was well tolerated.
“Despite the sample size limitations and the lack of statistical significance in the primary endpoint, we are pleased to see trends in clinical benefit in the study population,” said Hasan Jafri, chief medical officer at Aridis.
AR-301-002 is the first of two planned Phase 3 studies of AR-301. Aridis plans to start the second phase 3 trial after discussing the results of the current study with regulatory authorities, including in the US and the EU.
ARDS -28.02% to $0.89 before marketing on January 26
