ATyr Pharma is planning to assess its drug candidate ATYR1923 in a Phase II clinical trial to treat severe respiratory complications in individuals with Covid-19.

The US Food and Drug Administration (FDA) accepted the investigational new drug (IND) application of the candidate in this Covid-19 indication.

ATYR1923 is a fusion protein that specifically modulates neuropilin-2 to downregulate the innate and adaptive immune response in inflammatory diseases.

The drug candidate, being developed to treat interstitial lung diseases, is currently in a Phase Ib/IIa study involving patients with pulmonary sarcoidosis.

In preclinical studies, ATYR1923 was observed to downregulate T-cell responses, reducing the inflammatory cytokine and chemokine signalling linked to severe Covid-19.

Furthermore, the drug candidate improved lung function and also mitigated inflammation and fibrosis in multiple animal models with immune-mediated acute lung injury.

ATyr Pharma president and CEO Dr Sanjay Shukla said: “The inflammatory lung injury related to Covid-19 may be similar to that of interstitial lung diseases, or ILDs, for which ATYR1923 is currently being investigated.

“By targeting aberrant immune responses, we believe that ATYR1923’s mechanism of action has substantial overlap with this disease pathology and presents a compelling opportunity to potentially treat this subset of Covid-19 patients for which there are no approved therapies.”

The randomised, double blind, placebo-controlled Phase II study will evaluate ATYR1923 in 30 patients at up to ten centres in the US.

Participants will be given a single intravenous (IV) dose of either 1mg/kg or 3mg/kg ATYR1923 or placebo. The study aims to demonstrate safety and preliminary efficacy of the drug candidate.

According to data from a Phase Ib/IIa pulmonary sarcoidosis study, ATYR1923 was found to be generally safe and well tolerated without drug-related serious adverse events.