Regeneron's Covid-19 antibody cocktail shows promise, early data suggests it reduces symptoms and virus levels
Regeneron's antibody cocktail against Covid-19 has tasted success after preliminary results showed it reduced both virus levels and symptoms among infected but non-hospitalized patients. Though encouraging, experts said they want to see more data before calling the treatment "transformative".
Regeneron's antibody cocktail REGN-COV2 rapidly reduced viral levels [load] along with symptoms in infected Covid-19 patients, Dr George D Yancopoulos, President and Chief Scientific Officer of Regeneron, said in a statement. The greatest treatment benefit, he added, was in patients who could not produce antibodies naturally. "These patients were less likely to clear the virus on their own and were at greater risk for prolonged symptoms."
The antibody cocktail contains two potent lab-produced antibodies, which target a coronavirus protein named spike. It is this protein that helps the virus gain entry into human cells. Regeneron team tested its potential treatment on 275 patients, who tested positive but did not need hospitalization.
"What I think is fascinating is that it shows that antibodies really matter and the antibody to the spike protein was really helpful, particularly when people made the antibodies themselves," Dr Jeanne Marrazzo, the director of the division of infectious diseases at the University of Alabama at Birmingham, told CNN. "Whether it's antibody therapy or vaccine that targets these proteins, it sounds like we are on the right track. I think that's really encouraging."
The goal behind the trial was to assess the anti-viral activity and identify patients most likely to benefit from treatment, the company said. The participants were divided into three groups: a placebo group, a high-dose set that received 8 grams of REGN-COV2, and a low dose that got 2.4 grams of the experimental treatment.
After seven days, patients in the high-dose and the low-dose group saw reduced levels of virus in the throat. Besides, the placebo group took 13 days to see an improvement in symptoms. The high dose and the low dose group took 8 days and 6 days, respectively. Further, in the group that did not make antibodies on their own, 15.2% of placebo-treated patients, 7.7% of patients treated with a high dose, and 4.9% of patients with low dose required medical attention.
Next, the team will enroll 1,300 patients in the Phase 2/3 portion of the trial. According to the statement, the investigators will follow the participants for 29 days and assess viral shedding in the upper respiratory tract every 2-3 days roughly.
Commenting on the early findings, Eric Topol, director of the Scripps Research Translational Institute, told STAT: “There’s nothing bad about these results, you just can’t say much about how transformative this is going to be."
However, this is not the only antibody treatment that is being tested. Earlier this month, Eli Lilly said the early results showed that their experimental treatment reduced viral levels in some patients. Topola said that both companies need to show more data before they get emergency approval from the US Food and Drug Administration. “This doesn’t cut it, but it’s moving in the right direction, that’s for sure,” he added.