Novavax Inc. said on Monday that participants in its ongoing COVID-19 vaccine trials in South Africa and the UK can now receive additional shots, ensuring those who received a placebo can also get the active vaccine.
Allowing volunteers to cross to the other vaccine offers them an incentive to continue in the trials even when active vaccines are approved.
The company said it planned to cross over participants in its ongoing large, late-stage study in the United States and Mexico, for which the company will read initial clinical data during the second quarter.
If authorized for emergency use in the United States, Novavax's two-shot vaccine would help ramp up ongoing vaccination efforts in the country with currently approved vaccines from Pfizer BioNTech Moderna Inc and Johnson Johnson.
As part of the updated trial design, all participants of the trials will be offered the chance to receive an additional round of shots by the company in the UK and the U.S.
Participants who opt to do so will receive two additional doses of either vaccine for those who initially received placebo or placebo for those who had first received the vaccine.
All participants will continue to be blinded or not know if they have received the experimental vaccine or a placebo.