Treating with Monoclonal Antibodies for COVID-19 Prevention, Progression

The monoclonal antibody, bamlanivimab, was highly effective in reducing incidence of COVID-19 and progression in those with symptomatic SARS-CoV-2 infection in assisted living facilities residents and nursing staff, according to results from the BLAZE-2 study.

These findings were presented at Conference on Retroviruses and Opportunistic Infections (CROI) 2021 virtual sessions.

As the overwhelming majority of residents of assisted living facilities are seniors this has played a large role in this population having been disproportionately affected by incidence and mortality rates.

“The number one risk factor for progression to COVID disease from mild to severe and all the other consequences is age,” lead study author Myron Cohen, MD, Bate professor of Medicine, Microbiology and Epidemiology associate vice chancellor for Medical Affairs and global health director, Institute for Global Health and Infectious Diseases, University of North Carolina School of Medicine, said.

Cohen makes the point that monoclonal antibody therapies come from previous work done in HIV, and it made it an easier transition to creating these therapies for COVID-19.

Cohen participated in the BLAZE-2 study, which was a phase 3, randomized, double-blind, placebo-controlled, single-dose trial. There were 1175 participants dosed, and 966 were included in the prevention population. The prevention population included 299 residents for whom the median age was 76 years (range 31-104), 234 (78.3%) were aged ≥65, and 178 (59.5%) were female. All were considered at high risk for development of severe COVID-19.

Cohen said in this prevention group that was given the placebo, the virus did spread to both residents and staff. “Approximately a quarter of the people who were in the placebo group acquired COVID,” Cohen said.

In the prevention group that were given a single-dose of intravenous bamlanivimab, significant reductions were shown by day 57. “There was a 72% reduction in the acquisition of COVID and an 80% reduction in progression of disease…this is a very powerful difference in the 2 groups,” Cohen stated.

“What you are seeing is prevention of COVID-19 in the residents and the staff,” Cohen said. “Anecdotally, it is reported that COVID stops spreading around the facility.”

When the bamlanivimab-treated participants who still acquired COVID-19 were tested, there was a significant reduction of concentration of the virus in them, according to Cohen.

Cohen said results have not been analyzed in the secondary cohort who were asymptomatic or pre-symptomatic for COVID-19.

Cohen says the test findings in the nasal cavity point to a proof-of-concept that this therapy platform prevents or protects against progression of the virus. “Monoclonal antibodies can be developed very quickly, and that they arrive at the nose in sufficient concentration and protect from COVID causing infection in the nose,” Cohen said. “And when COVID is allowed to cause infection in the nose it can’t grow to the concentration it wants to.” 

Cohen says the key to preventing the progression to severe COVID-19 is to treat early in the disease state—within the first few days. And he says the reason he is confident about monoclonal antibodies is that other investigators in other studies are reporting similar, positive findings with these therapies at CROI.

Contagion spoke to Cohen and he discusses the various approaches to prevention and treatment, how monoclonal antibodies offer passive immunity, and why these therapies complement the COVID-19 vaccines.