Johnson & Johnson (J&J) has expedited the launch of a Phase I/IIa clinical trial of its Covid-19 vaccine candidate, Ad26.COV2-S, from September this year to the second half of next month.

The randomised, double-blind, placebo-controlled trial will assess the safety, reactogenicity and immunogenicity of the investigational vaccine recombinant in 1,045 healthy volunteers aged 18 to 55 years, and 65 years and above.

J&J, through its subsidiary Janssen Pharmaceutical, will perform the trial in the US and Belgium.

The company is also in talks with the National Institutes of Allergy and Infectious Diseases to potentially start the Phase III trial of the vaccine ahead of its original schedule, contingent on data from Phase I trials and regulatory approvals.