Brii's COVID-19 antibody slashes hospitalizations and deaths in late-phase trial, teeing it up to take on Regeneron

Add Brii Biosciences to the list of biotechs that have surged forward because of the COVID-19 pandemic. Brii, which only launched in 2018, now has phase 2/3 clinical trial data showing its antibody cocktail slashes the chances of hospitalization and death in high-risk outpatients with COVID-19 infections. 

The National Institutes of Health-sponsored ACTIV-2 study randomized 837 non-hospitalized COVID-19 patients at high risk of clinical progression to receive placebo or Brii’s antibody cocktail. As of the interim analysis, 12 people in the treatment arm had been hospitalized, compared to 45 of their peers on placebo. One patient on BRII-196/BRII-198 died, compared to nine people on placebo. Brii used the data to calculate that BRII-196/BRII-198 cuts hospitalizations and deaths by 78%.

Brii’s figures compare favorably to phase 3 data on Regeneron’s antibody cocktail. In a larger study of high-risk COVID-19 patients, Regeneron’s treatment reduced coronavirus-related hospitalization and all-cause death by 71%.

Full details on the effects of Brii’s antibodies are yet to emerge. Researchers are still following up with the patients in the study and analyzing questions such as whether the delay between the onset of symptoms and the start of treatment affects outcomes. Brii is also yet to share detailed safety data, saying only that 3.8% of patients on BRII-196/BRII-198 and 13.4% of patients on placebo had grade 3 or worse adverse events. “Few” events were considered to be drug related. 

RELATED: Brii's COVID-19 antibody cocktail remains active against variants, expects Q4 data readout

The efficacy of the cocktail against different variants will be another area of focus. Participants in the study enrolled at sites in the U.S., Brazil, South Africa, Mexico, Argentina and the Philippines between January and July. The timing of the trial and locations of the sites suggests subjects may have been infected with any one of a number of variants, including alpha, beta, gamma and delta. The cocktail retained its activity against those and other variants of concern in in vitro tests.

Efficacy against variants is now essential for anti-SARS-CoV-2 antibodies. After a slow start, sales of Regeneron’s antibody cocktail have taken off in recent months, generating $2.6 billion in the second quarter. In contrast, sales at Eli Lilly crashed after the FDA revoked the authorization of one of its antibodies as a monotherapy. 

Shares in Brii rose 8.8% to 38.95 Hong Kong dollars ($5.00) after the release of the top-line data. Brii went public in Hong Kong earlier this year, securing around $319 million to add to the hundreds of millions it raised as a private company.