REGN Regeneron Pharmaceuticals Inc

By Joseph Walker 

Regeneron Pharmaceuticals Inc. said its antibody drug reduced the risk of Covid-19 hospitalization or death by about 70% in a large clinical trial, the most definitive evidence yet that the medicine can aid recovery early in the course of disease.

Among subjects in a late-stage trial receiving a lower dose of the antibody drug, 1% were hospitalized or died, compared with 3.2% of patients receiving placebos, Regeneron said Tuesday. Study subjects getting a higher dose had a similar risk reduction, the company said.

Regeneron said it would seek FDA authorization for the lower dose after it proved similarly effective to the higher dose currently available. The change would effectively double manufacturing capacity of the medicine going forward.

Regeneron issued the high-level results in a press release. The data haven't yet been published in detail or in a peer-reviewed journal.

Regeneron's drug is among a handful of therapies authorized for Covid-19 patients to prevent severe disease and hospitalization. The drugs are targeted at patients early in the disease, when the virus is thought to be most susceptible to treatment.

The therapies have been scantily used, however, because of what doctors say is a cumbersome process for administering them and a lack of robust clinical trial data proving their effectiveness.

The new study data released by Regeneron on Tuesday could help boost enthusiasm for the medication among doctors and hospitals. The data could also eventually prompt influential expert panels convened by the National Institutes of Health and the Infectious Diseases Society of America to issue treatment guidelines recommending the drug's use.

Regeneron will likely have to release more detailed data, such as the baseline conditions of patients and a full breakdown of deaths and hospitalizations across study groups, before the drug receives stronger backing form medical groups, said Adarsh Bhimraj, a Cleveland Clinic physician who serves on the IDSA's guidelines committee.

"It looks promising but we still need to see the full data," said Dr. Bhimraj. He said monoclonal antibody drugs like Regeneron's so far look to be modestly effective because they require that a large number of patients be treated to show a significant reduction in bad outcomes from Covid-19.

"There's been no huge game-changers for Covid-19, so if I'm able to use it in 100,000 people to keep a couple hundred people out of the hospital there's some value in it," he said.

In November, the U.S. Food and Drug Administration cleared Regeneron's drug and another antibody treatment made by Eli Lilly & Co. for treating people with mild or moderate symptoms of Covid-19 who are at high risk of developing severe cases because of risk factors such as their age or underlying health conditions.

Both medicines are monoclonal antibodies, lab-engineered molecules that mimic the natural antibodies produced by the immune system to fight off viruses.

In October, former President Donald Trump received Regeneron's drug after he was infected with Covid-19 and later credited the medicine with his speedy recovery.

The initial authorizations in November were based on preliminary data from smaller earlier-stage studies. In recent weeks, the companies have issued findings from much larger studies that confirm the benefits seen in the earlier analyses.

The latest data comes from a Phase 3 study that compared two doses of Regeneron's drug, named REGEN-COV, with placebos in more than 4,000 Covid-19 patients with at least one risk factor such as obesity or cardiovascular disease.

The lower dose reduced the risk of hospitalization or death in study subjects by 70%, Regeneron said.

In the higher dose group, 1.3% of patients taking the drug were hospitalized or died, compared with 4.6% of those who received placebos, a 71% reduction of risk.

There was one patient death in each of the Regeneron drug study groups, and five deaths across both of the placebo groups.

"We are committed to working with the government, healthcare providers and others to support rapid and widespread adoption of REGEN-COV in appropriate patients," said George D. Yancopoulos, Regeneron president and chief scientific officer.

Regeneron's data suggest the drug's effectiveness is similar to Eli Lilly's drug cocktail, which combines a new monoclonal antibody, named etesevimab, to one called bamlanivimab that was authorized last year. The FDA authorized the cocktail in February based on trial data showing it reduced hospitalizations or death by 70%.

Regeneron also said Tuesday that the FDA recently updated a fact sheet on the drug to show that in laboratory tests it is no less effective against new coronavirus variants that were first identified in the U.K., South Africa and elsewhere.

By contrast, the FDA's most recently updated fact sheet for Eli Lilly's cocktail drug says it appears to be less potent against certain variants including those from South Africa and Brazil in laboratory tests. It is unclear whether the lab test findings will carry over to the drug being less effective in human patients, the FDA fact sheet says.

"There's a huge difference between what happens in a petri dish and what happens in a patient," said Dr. Bhimraj. An Eli Lilly spokeswoman didn't respond to a request for comment.

In addition, Regeneron said it had tested a new formulation of its drug that can be given as a quick shot, rather than via the intravenous infusions that are required now.

In a Phase 2 study, the new formulation reduced patients' virus levels as measured in samples taken from nasal swabs, but further studies may be required to show that it reduces the risk of hospitalization and death, a Regeneron spokeswoman said.

Write to Joseph Walker at joseph.walker@wsj.com

(END) Dow Jones Newswires

March 23, 2021 02:14 ET (06:14 GMT)

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