The Race for a Super-Antibody Against the Coronavirus

Even as vaccines are hailed as our best hope against the coronavirus, dozens of scientific groups are working on an alternate defense: monoclonal antibodies. These therapies shot to prominence just this month after President Trump got an infusion of an antibody cocktail made by Regeneron and credited it for his apparent recovery, even calling it a “cure.”

Monoclonal antibodies are distilled from the blood of patients who have recovered from the virus. Ideally, antibodies infused early in the course of infection — or even before exposure, as a preventive — may provide swift immunity.

An enthusiastic Mr. Trump has promised to distribute these experimental drugs free to anyone who needs them. But they are difficult and expensive to produce. At the moment, Regeneron has enough to treat only 50,000 patients; the supply is unlikely to exceed a few million doses in the foreseeable future.

Dozens of companies and academic groups are racing to develop antibody therapies. Already Regeneron and the drug company Eli Lilly have requested emergency use authorizations for their products from the Food and Drug Administration.

These drug companies have the long experience and deep pockets needed to win the race for a powerful antibody treatment. But some scientists are betting on a dark horse: Prometheus, a ragtag group of scientists who are months behind in the competition — and yet may ultimately deliver the most powerful antibody.

Prometheus is a collaboration between academic labs, the United States Army Medical Research Institute of Infectious Diseases, and a New Hampshire-based antibody company called Adimab.

The group’s antibody is not expected to be in human trials until late December, but it may be worth the wait. Unlike the antibodies made by Regeneron and Eli Lilly, which fade in the body within weeks, Prometheus’s antibody aims to be effective for up to six months.

“A single dose goes a long way, meaning we can treat more people,” said Kartik Chandran, a virologist at Albert Einstein College of Medicine and the group’s leader.

In mice and laboratory tests, Prometheus’s antibody protects against not just the coronavirus, but also the SARS virus and similar bat viruses — suggesting that the treatment may protect against any coronaviruses emerging in the future.

A study published last year recorded about 400 strains of bat-origin coronaviruses in China, some of which had already spilled over into people.

Among scientists, Dr. Chandran and Prometheus are famous for careful and clever work that has unearthed critical insights into deadly pathogens. While working on Ebola, for example, the team discovered a new entryway into human cells used by the virus, and used that information to design an antibody combination that works against all major strains of Ebola.

“They do very innovative stuff,” said Florian Krammer, an immunologist at the Icahn School of Medicine at Mount Sinai in New York. “If they find something cool, they dig deep.”

Antibodies are as variable as the people who produce them. Some antibodies are weaker than others; some target a different part of the coronavirus than others; and some are powerful protectors, while a small number may even turn against the body, as they do in autoimmune diseases.

Monoclonal antibodies are artificially synthesized copies of the most effective antibodies produced naturally by patients. In late February, AbCellera fished out an apparent winner from among 550 antibodies drawn from the blood of an infected patient. Barely three months later, partner Eli Lilly began the first trial of a synthesized version in patients.

Regeneron, which has a $450 million contract from the federal government to develop its treatment, was not far behind. Its drug is a cocktail of two antibodies. One was discovered in a patient in Singapore, while the other was made using a synthetic viral snippet in mice.

Regeneron expects to have enough of its cocktail to treat 300,000 patients within the next few months. The company may eventually produce about two million doses annually worldwide in partnership with Roche. Eli Lilly hopes to have 100,000 doses available later this month.

Even dozens of companies manufacturing antibodies could not produce the billions of doses required for the world — or just the minimum estimate of 25 million doses needed for Covid-19 patients and high-risk people in the United States alone.

And it’s not clear how quickly manufacturing capacity could be scaled up. For one, the treatments are made in specialized facilities with ingredients — sterile vials, protein resins, culture media — needed to make other antibodies and vaccines, as well.

“It’s a finite capacity, and there are only so many things you can do to try to increase that capacity,” said John Kokai-Kun, the director of external scientific collaboration at U.S. Pharmacopeia, an organization that monitors manufacturing quality.

The antibodies are also expensive to produce. Some cost up to $200,000 — even the cheapest cost about $15,000 — per year of treatment, making them unattainable for all but the richest of countries, according to a report released in August.

“I don’t see monoclonal antibodies being at large-scale use in the public,” Dr. Kokai-Kun said. “They’re just too complicated to make and too expensive to really be effective in that regard.”

Like vaccines, the antibodies have to be injected, and the amounts, which are calibrated to a person’s weight, can be significant. (Mr. Trump received eight grams — vaccine doses tend to be in micrograms or even nanograms.) The protection wanes after just a few weeks.

“That puts a strain on your manufacturing infrastructure already to make the kinds of doses that we think are going to be required worldwide,” said Andrew Adams, a vice president at Eli Lilly. “We have to start thinking about the populations that we should prioritize.”

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