FDA Panel Backs Moderna’s Vaccine

“The evidence for the vaccine highly outweighs any issues that we have seen,” said panel member Hayley Gans, a Stanford University pediatrics professor.

The vote came as the coronavirus pandemic continued its rampage, with a record 247,000 U.S. cases reported Wednesday alongside peaks in reported deaths and hospitalizations.

“We’re talking about a pandemic where we really need to move this forward, and there’s really an effort to get this done quickly,” said committee member Dr. Steven Pergam, infectious-disease specialist with Seattle Cancer Care Alliance. “There’s no doubt in my mind that it looks like the benefits outweigh the risks.”

The lone abstention came from Michael Kurilla, a director of clinical innovation with the National Institutes of Health. He declined to comment.

The FDA is expected to grant emergency approval for the Moderna vaccine late Friday, one week after doing so for the Pfizer vaccine. That would allow distribution of the Moderna vaccine to begin as early as this weekend.

Federal officials say they expect to distribute nearly six million doses of the Moderna vaccine to more than 3,200 locations around the U.S. in the initial batch, with distribution potentially starting within about 24 hours of FDA action.

Doses could start arriving at hospitals and other vaccination sites within days. More shipments will follow, and Moderna expects to deliver a total of 20 million doses by the end of December.

With both vaccines, which are given in two doses, federal officials expect to have enough this month to immunize about 20 million people, mostly health-care workers and residents of nursing homes and other long-term care facilities.

Moderna’s vaccine can be shipped and stored at higher temperatures than Pfizer’s, which requires special freezers and dry ice.

In voting to recommend approval of the vaccine, the FDA’s Vaccines and Related Biological Products Advisory Committee considered in depth the scientific results, including side effects, raised in Moderna’s clinical study of about 30,000 patients. The FDA doesn’t have to follow the panel’s advice, but it is expected to do so.

The Moderna vaccine has been shown to reduce the rate of Covid-19 disease with symptoms by 94.1% in a clinical study, which compared the vaccine to a placebo. The FDA termed the vaccine “highly effective” in its analysis released Tuesday.

There isn’t enough evidence regarding the use of the vaccine in a pediatric population younger than 18 or in pregnant or breast-feeding women, Rachel Zhang, an FDA medical officer, told the panel.

Dr. Zhang said that there were three cases of serious side effects among Moderna vaccine recipients that appeared to be related to the vaccine.

One was severe nausea and vomiting, and two involved facial swelling. Both cases of serious facial swelling happened in people who had prior dermal fillers for cosmetic purposes, and were successfully treated with medications. There was an additional case of lip swelling in another person who had prior dermal filler.

There were also a small number of cases of Bell’s palsy, or weakening of facial muscles, after vaccination. Dr. Zhang said the rate was consistent with what would be expected in the general population, but the FDA plans to monitor the situation.

Another FDA vaccine official, Doran L. Fink, said the agency is studying two cases of serious allergic reactions in people who got the Covid-19 vaccine from Pfizer and BioNTech in Alaska.

Dr. Fink said the FDA was working with Pfizer to revise the written prescribing information and fact sheets distributed with Pfizer’s vaccine to underscore the need for post-vaccination monitoring and how to manage an immediate allergic reaction.

The Moderna vaccine, developed in collaboration with the National Institutes of Health, was found in the FDA analysis not only to be effective in treating mild to moderate disease with certain symptoms, but also severe disease. The Pfizer vaccine was found to be 95% effective in a separate study.

Moderna also presented preliminary data suggesting that the first dose of its vaccine could reduce coronavirus infections that have no symptoms. A member of the FDA panel, Patrick Moore, said this would be “important for control of the epidemic” because it could be a sign the vaccine reduces viral transmission.

The Moderna study found that the most common side effects included injection-site pain, fatigue, headache and chills. Severe adverse reactions were rare but occurred more frequently after the second dose than after the first dose.

Moderna’s vaccine “offers the potential to address the public health crisis of Covid-19,” Jacqueline Miller, a Moderna senior vice president and therapeutic area head for infectious diseases, told the FDA committee members Thursday.

Moderna said that there was one anaphylactic reaction in a vaccine recipient in the study, but it occurred two months after the second dose in a person with a history of asthma and allergy to shellfish. The company plans to continue to monitor for such events.

The Moderna vaccine would be the first of several after Pfizer’s vaccine that are expected to build up the nation’s vaccine supply against the coronavirus pandemic, which has killed more than 310,000 Americans and 1.6 million people world-wide, according to Johns Hopkins University.

One thorny issue the panel confronted was whether placebo patients in the Moderna and Pfizer studies will automatically now get vaccinated. Ethical considerations suggest that they should, having sacrificed for the public. But a countervailing force is that researchers need to follow those patients as long as possible to be a comparison group to assess side effects of the vaccines.

Many panel members said during the hearing that, realistically, the placebo patients will have to be given an option to get the vaccine, given that vaccines now are becoming available across the U.S.

Moderna is exploring changing the design of its large study to offer its vaccine to people who previously received the placebo, to encourage them to remain in the study, the FDA said in a briefing document released earlier this week.

Write to Thomas M. Burton at [email protected] and Peter Loftus at [email protected]