US: FDA Allows Mix-and-Match Boosters For Covid Vaccines

On Wednesday, the US Food and Drug Administration said that it is authorizing the usage of “mix and match” strategy for people who are looking for a booster shot of a Covid vaccine after their primary series. “The FDA has determined that the known and potential benefits of the use of a single heterologous booster dose outweigh the known and potential risks of their use in eligible populations,” the agency said in a statement.

The authorized vaccines in the USA are Pfizer, Moderna, and Johnson & Johnson. And now, a single dose of any three of them can be used following completion of primary vaccination with a different Covid vaccine. The new decision also stated that people who received two Moderna shots and are 65 or older, over 18 and at high risk for Covid, or over 18 and have high occupational exposure, may now receive a booster.

All adults who received the one shot J&J vaccine more than two months ago are also eligible for a booster. The data supporting the decisions come from emerging research reviewed by the FDA. “Today’s actions demonstrate our commitment to public health in proactively fighting against the Covid-19 pandemic,” said acting FDA commissioner Janet Woodcock.

Earlier, there has been a long debate on mix and match concept and experts believed the best combination would be to substitute one mRNA vaccine with the other (Pfizer and Moderna). And in Canada, mixing vaccines was approved months ago. The advice from the federal health ministry has consistently been, “Don’t vaccine-shop. Take the vaccine that is provided on the day you go.” Many Canadians have received doses of different vaccines. The approved ones are AstraZeneca, Pfizer, and Moderna.