Bavarian Nordic has completed the participant enrolment in the Phase III clinical trial of its MVA-BN respiratory syncytial virus (RSV) vaccine candidate in adult patients aged 60 years above.

More than 20,000 participants are enrolled at 120 sites across Germany and the US for the randomised, global, double-blind trial, which commenced in April this year.

The trial’s primary objective is to evaluate the RSV vaccine candidate’s efficacy against lower-respiratory tract disease (LTRD) that is caused by RSV compared to placebo.

The company anticipates topline results from the Phase III study in mid-next year.

Bavarian Nordic CEO and president Paul Chaplin said: “The RSV Phase III trial is our largest single study to-date, and we are pleased to complete target enrolment within the projected timeframe.

“We would like to thank all the clinical trial sites and their personnel for their significant contribution to advancing our RSV vaccine candidate, and not least the many volunteers without whom innovation and progress in the development of novel vaccines would not be possible.

“Our RSV vaccine has shown great promise in clinical trials thus far confirming its significant potential to change the lives of adults at risk from RSV-related disease, and we look forward to seeing the results from the Phase III trial next year.”

The investigational RSV vaccine candidate MVA-BN RSV was developed using the company’s proprietary vaccine platform technology, MVA-BN.

It includes five distinct RSV antigens for stimulating a broad immune response against RSV subtypes (A and B).

MVA-BN RSV showed up to 79% vaccine efficacy in preventing symptomatic RSV infections in a double-blinded, placebo-controlled human challenge Phase II clinical trial.

Participants treated with the vaccine candidate also had significant reduction in viral load compared to placebo.

Simultaneously, Bavarian Nordic is also conducting a global Phase III trial of its Covid-19 booster vaccine candidate.

Enrolment of participants is progressing, with initial results expected early next year.