Omicron BA.4/BA.5-Adapted Bivalent COVID-19 Vaccine Shows Positive Early Trial Results

A 30-µg booster dose of the Omicron BA.4/BA.5-adapted bivalent COVID-19 vaccine (Pfizer-BioNTech) was found to offer better protection against the Omicron BA.4/BA.5 variants of COVID-19 than the original Pfizer-BioNTech COVID-19 vaccine (BNT162b2 Wild Type), according to the results of a phase 2/3 clinical trial (NCT05472038).

The Omicron BA.4/BA.5-adapted bivalent vaccine was found to be safe, tolerable, and immunogenic in younger and older adults. The FDA authorized the 30-µg booster dose for emergency use in children aged 12 years and older on October 12, 2022.

“The current dominance of BA.4/BA.5 and related sublineages underscores the importance of our data and science-based approach to develop a vaccine which is adapted to these prevalent strains of the virus and make it available in a timely manner,” said Ugur Sahin, MD, CEO, co-founder of BioNTech, in a recent press release.

The data also suggest that the new bivalent vaccine could be better equipped to fight multiple variants and reduce a surge of winter cases than the original vaccine, explained Albert Bourla, chairman and chief executive officer, Pfizer, in a recent press release.

“We are pleased to see encouraging responses just one week after vaccination in younger and older adults,” said Bourla in the press release.

During the multicenter, randomized, controlled trial, healthy adults were given a 30-µg or 60-µg booster dose of Pfizer and BioNTech’s Omicron BA.4/BA.5-adapted COVID-19 vaccine. Participants under age 17 were given a 30-µg dose, and the results were evaluated using safety, immunogenicity, and tolerability measures.

The researchers evaluated immunogenicity with a SARS-CoV-2 live virus fluorescent focus reduction neutralization test assay. The results showed that neutralizing antibodies were similar across groups who received booster doses 6 or 11 months after the original vaccine.

“These preliminary findings are consistent with our preclinical data showing a substantial increase in the neutralizing antibody response against the Omicron sublineages BA.4 and BA.5,” said Sahin in the press release.

The company will release new data in the coming weeks on the efficacy of the Omicron BA.4/BA.5-adapted bivalent booster a month following receiving it. Pfizer and BioNTech are also initiating studies to determine the safety and efficacy of the Omicron BA.4/BA.5-adapted bivalent booster among children aged 6 to 11 years.

“Since the earliest days of the pandemic, we have strived to transparently share data regarding our COVID-19 vaccines in the interest of public health,” Bourla said. “While we expect more mature immune response data from the clinical trial of our Omicron BA.4/BA.5-adapted bivalent vaccine in the coming weeks, we are pleased to see encouraging responses just one week after vaccination in younger and older adults.”

Reference

Pfizer and BioNTech Announce Positive Early Data From Clinical Trial of Omicron BA.4/BA.5-Adapted Bivalent Booster in Individuals 18 Years and Older. News Release. October 13, 2022. Accessed on October 13, 2022. https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-biontech-announce-positive-early-data-clinical