Moderna: COVID booster effective against omicron in tests, will still develop new shot

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CAMBRIDGE, Mass. - Moderna said Monday that its COVID-19 vaccine booster appears to provide protection against the rapidly-spreading omicron variant of the coronavirus, but it will still continue work developing a new shot specific to the strain.

The drug company said in a statement that preliminary data showed its booster shot currently being used in the U.S. and abroad increased neutralizing antibody levels against omicron 37-fold compared to pre-boost levels. A double dose of the booster — 100ug — provided an 83-fold increase in neutralizing antibody levels, the company said.

The news comes amid warnings about the variant’s rapid spread around the world, which has been detected in at least 89 countries. The World Health Organization first labeled omicron a variant of concern on Nov. 26.

The delta variant still accounts for more than 95% of estimated U.S. COVID-19 cases, according to the U.S. Centers for Disease Control and Prevention. But agency leaders say omicron is spreading faster than any past variant and will become the dominant strain nationwide within weeks.

Moderna said in its announcement that the couple would continue to develop an omicron-specific booster shot, which it expects to advance into clinical trials in early 2022.

"The dramatic increase in COVID-19 cases from the omicron variant is concerning to all. However, these data showing that the currently authorized Moderna COVID-19 booster can boost neutralizing antibody levels 37-fold higher than pre-boost levels are reassuring," Moderna CEO Stéphane Bancel said in a statement.

"To respond to this highly transmissible variant, Moderna will continue to rapidly advance an Omicron-specific booster candidate into clinical testing in case it becomes necessary in the future," Bancel added.

FILE - A health worker holds a vail containing Moderna COVID-19 booster vaccine. (Photo by Dinendra Haria/SOPA Images/LightRocket via Getty Images)

The company has tested various booster shots at different doses. It said data from a Phase 2/3 study of the 100ug booster dose suggested it was "generally safe and well-tolerated."

Moderna’s findings come after a large-scale analysis of data from South Africa showed the Pfizer-BioNTech COVID-19 vaccine seems to offer less defense against infection from omicron — but still good at protecting against hospitalization.

Pfizer and its German partner BioNTech are also currently testing three doses of the vaccine in babies and preschoolers after the usual two shots didn't appear strong enough for some of the children.

The World Health Organization noted that omicron is spreading rapidly even in countries with high vaccination rates or where a significant proportion of the population has recovered from COVID-19. It remains unclear if the rapid growth of omicron cases is because the variant evades existing immunity, is inherently more transmissible than previous variants, or a combination of both.

Still, public health officials in the U.S. and elsewhere continue to urge people to get vaccinated and receive a booster shot if they haven’t already in an effort to prevent overwhelmed hospital systems. The rapid spread of omicron and the ongoing fight against the delta variant come as the U.S. COVID-19 death toll has surpassed 800,000 people since the onset of the pandemic — the highest reported toll of any country.

"While it is rapidly increasing, we have the tools needed to fight #COVID19. Get vaccinated, get boosted," CDC Director Dr. Rochelle Walensky wrote in a tweet last week.

This story was reported from Cincinnati.