Bavarian Nordic provides update on COVID-19 booster vaccine program.

As previously reported, two weeks post a booster vaccination with ABNCoV2, the levels of neutralizing antibodies against the original SARS-CoV-2 variant (Wuhan index virus) were non-inferior to those stimulated in people vaccinated with Comirnaty and this result met the primary objective of the Phase III study. The Wuhan variant is no longer the primary concern, as the virus has mutated creating new circulating variants, such as Omicron XBB.1.5. In a follow-up analysis, when looking at this more distant variant, the levels of neutralizing antibodies induced by ABNCoV2 were lower than those stimulated by the non-adapted Wuhan-based Comirnaty, and fewer people had detectable antibodies following ABNCoV2 (64%) versus Comirnaty (85%). The levels of neutralizing antibodies induced by both vaccines were much lower than against the Wuhan variant.

A 6-month follow-up analysis will be conducted to evaluate the durability of the antibody responses from booster vaccination with ABNCoV2 and Comirnaty, which, if the Phase II durability results for ABNCoV2 are confirmed, may confirm an advantage over the comparator vaccine.

While safety data from the Phase III study will continue to be collected for 6 months, safety data from 4,205 individuals followed up for 2 months post vaccination showed ABNCoV2 to be well-tolerated with no serious adverse events being reported. These data support the current position of many of the regulators (e.g. FDA, EMA and WHO) that request variant-specific COVID vaccines that will likely have to be adapted each year like flu vaccines. Unfortunately, ABNCoV2 cannot be readily adapted within the seasonal timeframe and as such ABNCoV2 no longer represents a commercial opportunity for Bavarian Nordic.

Despite the lack of efficacy against distant and less virulent variants, the data generated in the overall development of ABNCoV2 may support the use of the cVLP platform in future pandemics, and the Company will discuss with the authorities how best to leverage the learnings from this development program.

Paul Chaplin, President and CEO of Bavarian Nordic said: “The world is in a different place now, and COVID-19 is no longer a public health crisis. However, as the disease continues to evolve, innovations in vaccine development are still warranted. We have generated robust data, so far demonstrating a favorable safety profile for the vaccine along with the ability to induce a strong and persistent immune response against earlier and more virulent strains, confirming the viability of the cVLP platform. We would like to thank our partners and everyone taking part in the Phase III study, and not least the Danish Ministry of Health for their support in this development that has validated a new vaccine platform for future pandemics.”

The Phase III study was designed to demonstrate non-inferiority of ABNCoV2 to Comirnaty measured by neutralizing antibodies against the SARS-CoV-2 virus (Wuhan wild type). The study enrolled a total of 4,205 adults who either previously completed primary vaccination or had already received one booster dose of a licensed COVID-19 vaccine. The active, controlled part enrolled 622 participants who were randomized to receive either a single 100 µg dose of ABNCoV2, or a single 30 µg adult booster dose of Comirnaty. The second part of the study evaluated the safety and tolerability of a single 100 µg dose of ABNCoV2 in 3,583 participants.