Bavarian Nordic A/S reported topline results from a Phase 3 non-inferiority clinical trial of ABNCoV2, a VLP-based, non-adjuvanted COVID-19 booster vaccine candidate. The two-part 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 1:1 to receive either a single 100 µg dose of ABNCoV2, or a single 30 µg adult booster dose of Comirnaty.

The results from this group showed that ABNCoV2 was non-inferior to Comirnaty® in terms of neutralizing antibodies against the SARS-CoV-2 (Wuhan wild type), thus meeting the study’s primary objective. The second part of the study, which is evaluating the safety and tolerability of a single 100 µg dose of ABNCoV2, has enrolled 3,583 participants into 2 cohorts according to whether they had completed primary vaccination only or primary plus booster vaccination. Results from this group will become available in the third quarter of 2023.

Given the continued mutations of SARS-CoV-2 and emergence of new and more distant variants, causing changes in the regulatory requirements and guidelines, the primary objective, while important, is likely insufficient to support a product approval on its own. ABNCoV2 has been designed to induce a broader protective response and therefore the secondary objectives that will compare ABNCoV2 to Comirnaty in terms of neutralizing antibodies against circulating variants will be important to understand the current effectiveness of ABNCoV2. These results are anticipated in the third quarter of 2023.

ABNCoV2 is a next-generation COVID-19 booster vaccine candidate, initially developed by AdaptVac, using their proprietary capsid virus like particle (cVLP) technology. Bavarian Nordic has licensed the vaccine candidate and has conducted the clinical development beyond Phase 1. ABNCoV2 has shown to be highly immunogenic in relevant preclinical models inducing a durable and highly protective response from a COVID-19 challenge. Results from a Phase 2 trial in previously vaccinated subjects has confirmed the ability of ABNCoV2 to significantly boost antibody titers to levels reported to be highly efficacious (>90%)1 against SARS-CoV-2, including previous variants of concern.