On Apr. 14, 2021, researchers running the Com-Cov study, launched in February to investigate alternating doses of the Oxford-AstraZeneca vaccine and the Pfizer vaccine, have announced that the programme was extended to include the Moderna and Novavax vaccines in a new study.

Led by the University of Oxford, run across nine National Institute for Health Research supported sites by the National Immunisation Schedule Evaluation Consortium, and backed through funding from the Vaccines Taskforce and the Coalition for Epidemic Preparedness Innovations, the additional study will seek to recruit adults aged over 50 who have received their first, or ‘prime’ vaccination in the past 8-12 weeks.