Moderna has completed the enrolment of participants for the Phase III COVE study of its vaccine candidate, mRNA-1273, against Covid-19.

The trial is being conducted along with the US National Institutes of Health (NIH) unit National Institute of Allergy and Infectious Diseases (NIAID) and the Biomedical Advanced Research and Development Authority (BARDA).

A total of 30,000 participants have been enrolled for the trial in the US and over 25,650 participants have been administered the second vaccine dose.

In July, Moderna initiated dosing the subjects in the Phase III trial of mRNA-1273.

Moderna CEO Stéphane Bancel said: “Completing enrolment of the Phase III COVE study is an important milestone for the clinical development of mRNA-1273, our vaccine candidate against Covid-19.

“Moderna is committed to rigorous scientific research and the highest data quality standards. We will continue to work in collaboration with regulators to advance mRNA-1273, which we hope will help defeat the Covid-19 pandemic.”

The randomised, placebo-controlled trial will evaluate mRNA-1273 at the 100µg dose level in participants, with the prevention of symptomatic Covid-19 disease as the primary endpoint.

Its key secondary endpoints are prevention of severe Covid-19 disease and infection by SARS-CoV-2.

The target vaccine efficacy (VE) against symptomatic Covid-19 disease has been set at 60%.

An independent Data Safety Monitoring Board (DSMB) chartered by NIH will review the trial data.

Formal study efficacy analysis will be initiated at 151 cases and two interim analyses after 53 and 106 cases.

Moderna will decide on submitting an application seeking emergency use authorisation from the US Food and Drug Administration (FDA) depending on an assessment of the vaccine’s potential benefit after obtaining the two months of median safety follow-up.

In August, Moderna reported that its mRNA-1273 vaccine candidate induced immune responses in older adults in the Phase I trial.