As the Omicron variant rages, Peter Marks, the FDA’s top vaccine regulator, said that getting a booster dose earlier than six months after initial doses may be the best way to guard against the ubiquitous variant.

Drugmakers like Pfizer, BioNTech and Moderna have announced that they are working on vaccines that target the Omicron variant.

But Marks, who is director of the FDA’s Center for Biologics Evaluation and Research (CBER), said last week that by the time we get an Omicron-specific vaccine manufactured, the Omicron wave will be over.

In an email to FDAnews, he said it is “too early to know whether vaccination with an Omicron-variant vaccine will provide a compliment of antibodies that will adequately protect against a spectrum of different variants,” as did the prototype vaccine.

“Shortening the length of time between completion of the primary series and a booster dose of the currently authorized vaccines may help reduce waning immunity and provide better protection, particularly against the Omicron variant,” he said.

Marks wasn’t specific about how much one should shorten the length of time between the primary series and the booster. But on Jan. 3, the FDA amended the Emergency Use Authorization for the Pfizer-BioNTech COVID-19 vaccine to reduce the time between the completion of primary vaccination of the Pfizer-BioNTech COVID-19 vaccine and a booster dose to at least five months.

Marks added that it’s still unclear how many boosters we’ll need, and when, as we face a future likely filled with other variants.

“We don’t yet know the appropriate regimen of additional booster doses of the COVID-19 vaccines that individuals will need to receive in order to provide continued protection against COVID-19 and the associated serious consequences that can occur, including hospitalization and death,” said Marks.

Compared with the original coronavirus strain first identified when the pandemic began, Omicron has a large number of mutations on the spike protein that could make it resistant to current vaccines.

Yet at the same time, the numbers of those newly infected with Omicron are starting to wane in certain parts of the world.

Marks added that there’s no way to know what the dominant COVID-19 variant will be going forward.

It is “somewhat premature to predict in the midst of this incredible surge in Omicron cases, what the primary circulating variant will be in the coming months, as we have already seen how rapidly we can move from one variant to another,”  he said, adding that the agency “will carefully evaluate the data and information as it becomes available in making any future determinations.” — Suz Redfearn