Dr. Marty Makary, chief of the FDA, has expressed doubts about the agency approving the COVID-19 vaccine for winter, stating that additional data is still required.

The Food and Drug Administration on Tuesday named Dr. Vinay Prasad — a hematologist-oncologist who has been accused of spreading misinformation about Covid vaccines and was an outspoken critic of the agency’s decision to approve Covid shots in children — as its new vaccine chief.

Vinay Prasad, named to lead the FDA agency tasked with regulating vaccines and gene therapy, has made controversial comments regarding the government response to the COVID-19 pandemic.