Viruses Mutate More Nimbly Than Therapies Hobbled by FDA Regulations

(p. A7) In a laboratory in New York City, researchers coaxed a key piece of the coronavirus — its infamous outer “spike” — to mutate so that it became invisible to disease-fighting antibodies, according to a new study that has not yet been published in a scientific journal.

The provocative finding should not set off alarm bells, experts said. The altered spikes were not attached to the real coronavirus, which mutates at a much slower pace than most laboratory viruses. But the study does underscore the need for treatments and vaccines that attack the virus in different ways, so that if the pathogen manages to evade one approach, another will be waiting in the wings.

“It’s an old story for virology,” said Dr. Sallie Permar, a virologist and pediatrician at Duke University who was not involved in the study. “If you only target one little region, that virus is going to find a way to get away from it. It’s why viruses are so successful in this world.”

. . .

Several types of monoclonal antibodies are now in clinical trials. If all goes well, such concoctions might not only treat coronavirus infections but also prevent them. That could help millions of people, especially as the world awaits a vaccine, said Akiko Iwasaki, an immunologist at Yale University who was not involved in the study.

But the new findings also hint that single-antibody formulations “may not be as successful,” Dr. Taylor said, at least in the long term. Developing a cocktail containing a diverse blend of antibodies could be a safer bet.

Such mixtures would also more accurately mimic the body’s natural response to the coronavirus. In the study, viruses flushed with samples of convalescent plasma — fractions of blood donated by people who have recovered from Covid-19 — struggled to infect cells.

Some scientists, including those at American biotechnology company Regeneron, are already attempting this combo approach, mixing two potent types of monoclonal antibodies into a single treatment.

But Dr. Iwasaki pointed out that antibody cocktails might be tougher to bring to market. “Every time you make a drug, you get approval for each component separately,” she said. . . .

The lesson of diversity might be even more powerful for vaccines, which can marshal a multifaceted immune response. Some immune cells and molecules will be tailored to home in on the spike, whereas others might prefer other parts of the virus. Vaccines that present the body with many pieces of the coronavirus, rather than the spike alone, could have a better shot at triggering a suite of these defenses, said Dr. Taia Wang, an immunologist at Stanford University who was not involved in the study.

For the full story, see:

Katherine J. Wu. “Experiment on Spike Protein Shows Obstacles of Mutation.” The New York Times (Wednesday, July 29, 2020): A7.

(Note: ellipsis added.)

(Note: the online version of the story has the date July 28, 2020, and has the title “The Coronavirus Could Dodge Some Treatments, Study Suggests.” The online version has an extra paragraph that does not appear in the print version. In my quotations above, I stick to the print version.)

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