Histogen and its partner Amerimmune have reported top-line data from the Phase I clinical trial where emricasan was found to be safe and well-tolerated in symptomatic patients with mild Covid-19.

A pan-caspase inhibitor, emricasan is intended to lower the enzyme activity associated with inflammation and apoptosis.

The double-blind, randomised, placebo-controlled single-site Phase I trial analysed safety, tolerability and preliminary efficacy of a twice-daily 25mg dose of emricasan in 13 patients in the outpatient setting.

Subjects enrolled at a site in New York City, US received either the treatment or placebo for 14 days and were followed up for a month.

The trial also evaluated several clinical and lab measures and patient-reported outcomes using the US Food and Drug Administration’s (FDA) Covid-19 symptom assessment tool.

According to results from the trial, emricasan was found to be safe and well-tolerated throughout the 14 days of dosing as well as by day 45 of the follow-up period versus placebo.

In addition, no serious adverse events relating to the drug were reported.

Subjects in the emricasan arm experienced a total mild-Covid-19 symptom resolution, including cough, headache, and fatigue by day seven, which continued to day 45.

Histogen noted that subjects receiving placebo did not have a resolution of the disease symptoms until day 45.

Furthermore, improvements were observed in all subjects in the emricasan arm that demonstrated reductions in caspase biomarkers, while those in the placebo arm had symptoms linked to Covid-19 and lab findings.

Histogen president and CEO Richard Pascoe said: “These positive results further reinforce the extensive clinical safety database of emricasan and strongly suggest that emricasan can potentially be developed as a therapeutic treatment for mild to moderate Covid-19, as well as other viral inflammatory diseases.”

In another development, Augmenta Bioworks and TFF Pharmaceuticals have selected monoclonal antibody, AUG-3387, to progress it into the clinic as a potential inhaled therapy for Covid-19 as part of their joint development and partnership agreement.

The companies intend to develop the antibody for Covid-19 patients who are at high risk of developing severe disease but have not been hospitalised yet.

The drug will also be analysed for preventing Covid-19 in people who are at increased risk of developing severe disease.