Moderna has begun dosing patients in a clinical trial testing its omicron-specific Covid-19 vaccine booster, the company announced Wednesday.
The Phase 2 study – Modern’s first trial of the omicron – specific vaccine in humans – will assess the safety, tolerability and immune response generated by the shot in adults.
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Laboratory data from Moderna as well as studies published by the Centers for Disease Control and Prevention show that the drug manufacturer’s existing booster shot still provides protection against the new variant, especially against serious illness.
But Moderna said new data, published Wednesday in The New England Journal of Medicine, shows about a six-fold decrease in the ability of the antibodies to neutralize the omicron variant compared to the original strain, six months after the booster.
The company’s announcement comes a day after Pfizer and BioNTech announced they were launching a clinical trial to test their own modified vaccine targeting the omicron variant.
The extremely contagious variant now accounts for virtually all new cases of Covid in the United States, according to the CDC.
Moderna enrolls two groups in its clinical trial: People who received two doses of their vaccine at least six months ago, and people who received two doses plus a booster shot at least three months ago.
The company said it expects to enroll about 300 participants in each part of the trial, which will be conducted at up to 24 locations in the United States
Bill Hanage, an epidemiologist at the Harvard TH Chan School of Public Health, said Moderna’s experiments will allow researchers to know how much benefit there is in training the immune system to attack the new variant.
“The drop in neutralizing antibodies to omicron, which they report six months after the boost, is enough to allow the virus to start an infection, but the immune response is still strong enough to handle it pretty well in the vast majority of people,” he said. he.
Moderna has previously said it is in discussions with public health leaders about potentially deploying an omicron-based booster this fall.
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