News that Moderna was inching closer to requesting full approval of its COVID vaccine by the U.S. Food and Drug Administration has led to some questions surrounding the approval process for the coronavirus vaccines this week.
Currently, no coronavirus vaccine is fully approved by the FDA, but three were given emergency use authorization by the agency.
They include vaccines from Pfizer-BioNTech, Moderna and Johnson & Johnson, the last of which regulators recommended be paused Tuesday while they investigate reports of potentially dangerous blood clots in a small number of women.
Emergency use authorization allows a vaccine to become available prior to full approval in the case of public health emergencies. The FDA can revoke the EUA at any time.
"The vaccines met FDA’s rigorous scientific standards for safety, effectiveness, and manufacturing quality needed to support emergency use authorization," the Centers for Disease Control and Prevention states on its website.
FDA approval of a drug, which requires a rigorous and structured process, means that data on the drug’s effects have been reviewed by the Center for Drug Evaluation and Research, which rules on whether the drug's provided benefits "outweigh its known and potential risks for the intended population," according to the agency's website.
Moderna, citing data from its phase three clinic trial, reported its COVID-19 vaccine was more than 90% effective at protecting against COVID and more than 95% effective against severe disease up to six months after the second dose, the company said Tuesday.
The update brings Moderna a step closer to filing its request for full U.S. approval, CNBC reports.
Once it gets full approval, Moderna can begin marketing the shots directly to consumers and selling them to individuals and private companies in the U.S.
Similarly, Pfizer and BioNTech said at the end of March that data from their Phase 3 trial showed high levels of protection against COVID six months after second doses.
"Because of that, that means that Pfizer is now going to be able to apply for the FDA for the full approval," Chicago Department of Public Health Commissioner Dr. Allison Arwady said at the time. "It's been under emergency use authorization, but that step is the part that lets you actually move ahead and apply for the full approval authorization, which is a big deal and exciting."
Since then, the companies have requested the FDA expand the emergency use of their COVID-19 vaccine to include adolescents aged 12 to 15.
Meanwhile, U.S. health officials are weighing next steps as they investigate a handful of unusual blood clots in people who received Johnson & Johnson’s COVID-19 vaccine — a one-dose shot that many countries were eagerly awaiting to help speed virus protection.
It’s not clear if the exceedingly rare reports — so far, six cases out of more than 7 million inoculations in the U.S. — really are linked to the J&J vaccine. But the government recommended a pause in J&J vaccinations on Tuesday, just a week after European regulators declared that such clots are a rare but possible risk with the AstraZeneca vaccine, a shot made in a similar way but not yet approved for use in the U.S.