On Thursday, a committee of advisers to the Food and Drug Administration will meet for the second time in as many weeks to review an experimental coronavirus vaccine.
The panel last week endorsed Pfizer and BioNTech's shot, clearing the way for the regulator to issue a historic emergency authorization the next day, and this week convenes to review Moderna's candidate.
Both vaccines were found in large trials of tens of thousands of volunteers to be strongly effective, preventing COVID-19 in nearly all participants who received them. FDA scientists affirmed the companies' claims in their own reviews, issuing detailed analysis of Pfizer and BioNTech's data last week and of Moderna's this Tuesday.
Thursday's meeting will cover some of the same points as last week's, but could feature new questions and emerging concerns. A vote by the committee in support of Moderna's vaccine would likely lead to an FDA authorization within days.
BioPharma Dive will be tracking the meeting, which runs from 9:00 am to 5:15 pm ET, and report back here. Check back often as we update this page throughout the day.
Updated 10:20 am
Sharp-eyed pharmacists administering some of the first doses of Pfizer and BioNTech's vaccine following last week's authorization noticed the vials contain more than the five doses they're supposed to hold.
Extra drug product in vials, or "overfill," is common with injectable medicines, but with supplies of Pfizer's vaccine extremely short, the revelation there may be six or even seven doses in each vial was met with some surprise.
Doran Fink of the FDA noted Thursday that, per instructions for the vaccine, 1.8 mL of diluents are supposed to be added to the 0.45 mL of vaccine in each vial. As each doses is 0.3 mL, it's "not entirely unexpected" there would be more than five doses, Fink said.
The FDA has reportedly told state health officials the extra doses can be used, rather than discarded as is usual practice with overfill.
But the issue raised alarm bells for at least one committee member, who had asked Fink whether the extra doses changed the FDA's confidence in Pfizer's manufacturing process.
"We do feel confident that we have enough information to justify issuing an EUA for this vaccine," said Fink. — Ned Pagliarulo
Doran Fink, a deputy director for the FDA division that oversees vaccines, made a point to address reports of allergic reactions observed in four healthcare workers who received Pfizer and BioNTech's vaccine following authorization in the U.K. and U.S.
Fink predicted there "may be additional reports," but noted the cases are being found through established vaccine safety surveillance systems that are "working exactly as designed."
"While the totality of data at this time continue to support vaccinations under the Pfizer EUA, without new restrictions, these cases underscore the need to remain vigilant during the early phase of the vaccination campaign," Fink said. "We will do the same for Moderna if [its vaccine is] authorized."
The FDA is currently working with Pfizer to update the prescribing information for its shot and to draw more attention to the need for monitoring immediately after vaccination. Prescribing information for the vaccine already warns against administering to people with a history of severe allergies, and caution medical staff to have treatment on hand in case of emergency.
Fink said the agency doesn't have enough information yet to make any new recommendations. — Ben Fidler
Today's meeting builds to a single question, on which advisory committee members will be asked to vote yes or no: "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?"
Restricting an authorization to people 18 and over could result in a slightly different vote outcome. Last week, the FDA asked to authorize the Pfizer and BioNTech vaccine for people 16 and older, a question on which four of the 22 panel members voted no.
Two of them, David Kim from the Department of Health and Human Services and Archana Chatterjee from Rosalind Franklin University, said they voted no because they didn't believe there was enough data to support authorization in the 16- and 17-year-olds. Moderna's Phase 3 trial didn't enroll anybody under age 18, so that will not be debated.
A third no vote came from Oveta Fuller of the University of Michigan, who believes the Pfizer and BioNTech vaccine should be used in expanded access trials to gain more data. She could make the same argument this week, too.— Jonathan Gardner
Like last week, Arnold Monto, a professor and epidemiologist at the University of Michigan, is leading Thursday's meeting.
The first two presentations in the morning are repeats from last week — going over the FDA's emergency use authorization process and questions around running a placebo-controlled clinical trial after an authorization. But the FDA has built in more time for Q&A following each presentation this time around, perhaps taking to heart criticism last week's meeting was rushed.
Moderna's chief medical officer, Tal Zaks, will present his company's data before lunch, after which an open public hearing will follow.
The FDA's presentation begins at 2, while the real meat of the committee's discussion will happen between 3:10 pm and 5:15 pm.
Last week, the experts ran out of time after their vote and the meeting adjourned without any being able to explain their votes. Watch the clock today to see if this time around they get more time to discuss. — Ned Pagliarulo
The FDA has been concerned the public will be hesitant to receive a vaccine tested in the fastest development effort in history. The regulator has responded by attempting to make its vaccine reviews transparent. A crucial part of that plan involves holding and broadcasting advisory committee meetings for each emergency authorization application. The result: two meetings, seven days apart, for two similar shots.
Thursday's meeting, however, may not be just a repeat of last week. Moderna's vaccine appears to have a slightly different profile than Pfizer and BioNTech's, most notably a perhaps more pronounced slate of side effects. (More on that in the next section.)
One side effect in particular, a type of facial paralysis known as Bell's palsy, was observed in a few participants in both Pfizer's and Moderna's trials, and will likely feature in the day's discussion.
Another emerging issue is whether one dose of vaccine, rather than two, could be effective and should be more formally tested, given Moderna's and Pfizer's limited supplies.
With rollout of Pfizer's vaccine now underway, committee experts may ask about four cases of allergic reactions reported among some of the first people to get the shot, and whether there is any reason to believe the same issue may occur with Moderna's.
Panelists last week also ran out of time discussing a number of critical topics, including questions of when trial participants who originally received placebo should get vaccinated and how companies should adjust their studies when an authorized vaccine is more widely available. The same points could come up again Thursday. — Ben Fidler
In many important ways, the two shots are very similar.
Both consist of genetic sequences that encode for virus proteins, rather than the virus itself, to teach the immune system to recognize and fight the coronavirus. Both appear to be similarly and strongly effective at preventing COVID-19 across age, race, ethnicity or gender. And while we don't know yet if either can slow or stop transmission of the virus, data are expected from each developer soon.
But there are differences, too. Moderna's shot uses a higher dose of mRNA than Pfizer's and appears to be slightly less tolerable, with vaccination leading to higher rates of side effects like pain, chills and fever — particularly after the second dose.
Moderna's two-shot regimen is spaced four weeks apart, compared to three for Pfizer. And Moderna's vaccine can also be stored at warmer temperatures than Pfizer's, and stays stable in a standard refrigerator for longer.
Additionally, Moderna is seeking emergency clearance for its vaccine in adults 18 and older, while Pfizer's FDA authorization included 16 and 17 year olds. — Ben Fidler
Not even the most bullish optimist would have predicted as 2020 dawned that Moderna would have a medicine on the cusp of regulatory clearance by the end of the year. The scale of the pandemic, along with the government and investor resources put toward combating it, has changed that outlook considerably.
Authorization of Moderna's vaccine would bring further validation of its messenger RNA technology, which is similar to what's used in Pfizer's and BioNTech's shot and has proven more potent than expected in testing against the coronavirus.
Moderna hopes to use mRNA in preventive vaccines for other infectious diseases, as well as drugs for cancer and rare disorders. Lessons learned from the past year of development could help those hopes along.
An authorization could also give Moderna a place on national immunization schedules. Looking ahead, CEO Stéphane Bancel has proposed a combined vaccine to fight several respiratory viruses, including influenza and coronavirus.
More broadly, an authorization would cement Moderna's place in the national spotlight and give real backing to the company's ballooning market valuation. — Jonathan Gardner