Innovative ABNCoV2 COVID-19 Booster Vaccine Induces Long-Lasting Protection

This week, the fully integrated vaccines company Bavarian Nordic announced the phase 2 trial results from their COVID-19 booster vaccine candidate, ABNCoV2.

ABNCoV2 is a non-adjuvanted, investigational COVID-19 booster vaccine that utilizes capsid virus like particle (VLP) technology. After a 12-month follow-up analysis, investigators determined ABNCoV2 induced high levels of protective antibodies, neutralizing the Wuhan/wild type strain and the Beta, Delta, and Omicron BA.4/5 variants of concern.

Investigators recruited 36 participants, none of whom had previously received a COVID-19 booster shot. The participants had no reports of COVID-19 infection, nor positive PCR results for SARS-CoV-2 since vaccination in the study.

A year after booster vaccination with ABNCoV2, participants retained high levels of neutralizing antibodies, at more than 90%. A separate analysis of 40 participants enrolled in the trial were tested against Omicron XBB.1.1. At 2 weeks after vaccination, the ABNCoV2 booster induced neutralizing antibodies against XBB.1.1 in 43% of study patients.

“It is encouraging to see durable antibody levels against the earlier variants of concern 1 year after vaccination with ABNCoV2, that has not been shown for other COVID19 vaccines,” said Paul Chaplin, president and CEO of Bavarian Nordic. “While it is believed that the currently circulating XBB variants are less virulent, the weakened immune responses against this more distant variant is a concern and needs to be carefully evaluated in the ongoing Phase 3 trial.”

A double-blind, controlled, phase 3 trial was initiated in September 2022. The primary trial endpoint was to determine the noninferiority of ABNCoV2 compared to the Pfizer-BioNTech (Comirnaty; BNT162b2) COVID-19 booster vaccine, determined by neutralizing antibodies generated against the Wuhan/wild type variant. Bavarian Nordic noted that ABNCoV2’s ability to neutralize other variants of concern will be assessed as secondary endpoints, with trial results expected in July 2023.

Bavarian Nordic is focused on vaccine research, development, manufacturing, and commercialization. The company worked with the US government to develop smallpox and mpox vaccines, and has a strong portfolio of vaccines for travelers and endemic diseases.