Bavarian Nordic has reported additional data from the Phase II clinical trial of boosting with its non-adjuvanted Covid-19 vaccine candidate, ABNCoV2.

According to the trial data, participants inoculated priorly with approved messenger ribonucleic acid (mRNA) or adenoviral vaccines showed ABNCoV2 vaccine elicited a substantial improvement in neutralising antibodies against the Omicron variant of the SARS-CoV-2 virus.

Furthermore, in most of the trial subjects, a rise in neutralising antibodies was in line with those seen against the Wuhan variant.

While the neutralising antibody titers against Omicron were found to be lowest versus other variants, they were boosted to levels consistent with an increased protection level across both 50μg and 100μg dose groups. 

Topline results from the trial reported previously showed that one dose of 50μg or 100μg ABNCoV2 could enhance neutralising antibodies. 

ABNCoV2 was developed initially by AdaptVac leveraging its capsid virus-like particle (cVLP) technology and Bavarian Nordic licenced the worldwide marketing rights to the vaccine.

Bavarian Nordic president and CEO Paul Chaplin said: “We now have demonstrated a large range of immune responses against different variants of concern, including Omicron.

“This encourages us to continue to rapidly initiate our Phase III study and subsequently submit this vaccine for licensure.” 

With support from the Danish State, the company intends to commence a Phase III programme of the vaccine soon.

The programme will enrol nearly 4,000 seropositive participants who will be given a booster dose of 100μg ABNCoV2 or an mRNA-based vaccine.

This programme is aimed at showing non-inferiority of ABNCoV2 compared to the currently licenced mRNA vaccine.