On April 29, the NIH recommended against use of the antiparasitic drug ivermectin for treatment of COVID-19 outside of a clinical trial. The recommendation was made because recent randomized, placebo-controlled trials of ivermectin have produced negative results and because alternative drugs that have been shown to be effective for treatment of COVID-19 are available.

The FDA has expanded the Emergency Use Authorizations (EUAs) for the mRNA COVID-19 vaccines manufactured by Pfizer-BioNTech (Comirnaty) and Moderna (Spikevax) to allow for their use as a second booster dose ≥4 months after a first booster dose in adults ≥50 years old and in persons aged ≥12 years (Pfizer) or ≥18 years (Moderna) who have undergone solid organ transplantation or have a condition that compromises the immune system to a similar extent.