A high-profile meeting of the FDA's Vaccines and Related Biological Products Advisory Committee underway today remained on track toward a likely vote supporting a recommendation for emergency use authorization (EUA) of Moderna Inc.'s COVID-19 vaccine, mRNA-1723, with FDA support for its issuance remaining strong.

As the day-long meeting kicked off, Doran Fink, deputy director for the agency's division of vaccines and related products, said his team felt "confident that we have enough information to justify issuing an EUA for this vaccine, should everyone agree that the benefits outweigh the risks based on the clinical data."

Shares of Moderna (NASDAQ:MRNA) climbed 2.9% to $141.03 by midday.

Following two reports of anaphylaxis and one report of a possible allergic reaction to the first vaccine to receive an EUA, Pfizer Inc. and Biontech SE's BNT-162b2, Fink addressed new reports today of two workers at an Alaska hospital who suffered allergic reaction to vaccine. He said the agency was working with Pfizer to revise labeling for the product, but meanwhile anticipated that there would be more reports of such reactions, underscoring the need to remain vigilant during the early phase of the vaccination campaign.

Keenly aware of the interest in the issue and its import as wider distribution of COVID-19 vaccines get underway, Moderna's team also addressed the issue. During the course of the Cambridge, Mass.-based company's ongoing phase III study of mRNA-1723, its team has "actively scrutinized" its safety data to identify and analyze possible cases of anaphylaxis, said David Martin, the firm's vice president of pharmacovigilance. So far, it has found no cases suggestive of anaphylaxis to the vaccine candidate, though two anaphylactic reactions have been reported to the company as adverse events, Martin said.

One case occurred in the placebo arm of the trial, called Study 301, and the other occurred in the mRNA-1273 arm. The placebo arm event occurred 10 days after the first dose, and was attributed to co-administration of radiocontrast dye, he said. The mRNA-1273 event occurred 63 days after the second dose of the vaccine in a person with a history of asthma and allergy to shellfish.

The meeting continues through the midday with an hour of open public comment, to be followed by time for additional questions and answers for Moderna by VRBPAC panelists. Following an afternoon presentation by the FDA, the members will vote at 3:10 p.m. ET on just one question: "Based on the totality of scientific evidence available, do the benefits of the Moderna COVID-19 vaccine outweigh its risks for use in individuals 18 years of age and older?"

BioWorld will offer further coverage of the meeting with delivery of today's full issue.