EMA’s human medicines committee (CHMP) has started a rolling review of Ad26.COV2.S, a COVID-19 vaccine from Janssen Vaccines & Prevention B.V.

The CHMP’s decision to start the rolling review is based on preliminary results from laboratory studies and early clinical studies in adults. These studies suggest that the vaccine triggers the production of antibodies and immune cells that target the SARS-CoV-2 coronavirus.

The company is currently conducting trials in people to assess safety and immunogenicity (how well the vaccine triggers a response against the virus), and effectiveness. EMA will evaluate data from these and other clinical trials as they become available.

The rolling review will continue until enough evidence is available for a formal marketing authorisation application.

EMA will assess the vaccine’s compliance with the usual standards for effectiveness, safety and quality. While EMA cannot predict the overall timelines, it should take less time than normal to evaluate an eventual application because of the work done during the rolling review.