Brii Biosciences has reported positive interim analysis data from the Phase III ACTIV-2 clinical trial of its combination treatment of BRII-196 plus BRII-198 in non-hospitalised Covid-19 patients.

BRII-196 and BRII-198 are non-competing SARS-CoV-2 monoclonal neutralising antibodies obtained from convalesced Covid-19 patients.

Funded by the National Institutes of Health (NIH) unit National Institute of Allergy and Infectious Diseases (NIAID), the randomised, blinded, controlled adaptive platform ACTIV-2 master protocol is led by the NIAID-sponsored AIDS Clinical Trials Group.

The ACTIV-2 trial is assessing the safety and efficacy of various experimental drugs to treat symptomatic Covid-19 in non-hospitalised adults who are at increased progression risk.

These subjects were enrolled within ten days of Covid-19 symptom onset.

The NIH initiated the Phase II/III ACTIV-2 trial of Brii Biosciences’ combination therapy in January this year.

Earlier this month, Brii Biosciences reported that the ACTIV-2 trial in the US completed enrolment for the Phase III part assessing BRII-196 plus BRII-198 for Covid-19.

The Phase III part analysed the potential of the combination therapy to prevent the composite goal of either hospitalisation or death by day 28 of the trial in 837 participants.

Data showed that the treatment provided a statistically significant decline of 78% relative risk in the combined goal versus placebo.

Based on partial follow-up of these subjects, a decline in hospitalisations, as well as deaths, was noted.

In the treatment arm, Grade 3 or higher adverse events (AEs) were seen less often, with few of the events linked to the drug.

Furthermore, drug-related serious adverse events (SAEs) or deaths were not reported in either of the arms in the trial.

The Phase III part follows a Phase II trial, where BRII-196 plus BRII-198 combination treatment met the safety and efficacy criteria of the study.

Brii Biosciences CEO Zhi Hong said: “As we all continue to research and evolve our understanding of this novel virus, Brii Biosciences is committed to advancing global standards of treatment for a broad range of patients at various stages of disease as well as those affected by the newly-emerging Covid-19 variants.

“We look forward to completing the analysis of this full data set and sharing our findings from this large global trial.”

According to the latest in vitro pseudovirus testing data, the combination therapy maintains activity against key SARS-CoV-2 variants of concern, including Alpha, Beta, Gamma, Epsilon, Delta and Lambda.