Covid-19 roundup: FDA authorizes Pfizer-BioNTech booster for 12-to-15-year-olds; Early results suggest antivirals may hold up against Omicron
Children between the ages of 12 and 15 years old are now eligible for a third dose of the Pfizer-BioNTech vaccine after the FDA authorized it Monday, as well as a third shot for those between 5 and 11 who are immunocompromised.
The FDA also shortened the time between the completion of a primary vaccine and a booster shot to five months for Pfizer’s jab, although Moderna’s booster interval remains at 6 months. The moves come as Omicron has ripped through the US, causing the number of positive cases to skyrocket.
“Throughout the pandemic, as the virus that causes Covid-19 has continuously evolved, the need for the FDA to quickly adapt has meant using the best available science to make informed decisions with the health and safety of the American public in mind,” acting FDA Commissioner Janet Woodcock said in a statement.
The expanded booster EUA comes after reviewing real-world data in Israel, including safety data from 6,300 people between the ages of 12 and 15. All got a booster at least five months after the original two doses. There were no new safety concerns after a booster shot, and there were no new cases of myocarditis or pericarditis reported. — Josh Sullivan
Early results suggest antivirals may hold up against Omicron
As the Omicron variant — now dominant in the US — threatens the efficacy of currently available vaccines and monoclonal antibodies, new data suggest that three antivirals may hold up against the mutation.
Gilead’s remdesivir, Merck’s molnupiravir and Pfizer’s Paxlovid will likely retain their activity against all current variants of concern, including Omicron, as the target proteins of these antivirals are highly conserved, according to results from a new study posted on bioRxiv.
It’s important to note that these results are from a preprint, and have not been peer-reviewed or published in a journal.
“These results indicate that when more VOCs arise, due to antigenic drift, there is a high probability that they will remain sensitive towards current antivirals,” the preprint states. “It is therefore important to continue both vaccine development as well as antiviral research, as they are both essential armor and complement each other in the strategy to control the current pandemic.”
While remdesivir was the first FDA-authorized antiviral to treat Covid-19 (and is administered via IV), two oral options from Merck and Pfizer got the green light just a couple of weeks ago. Pfizer’s at-home pill, sold commercially as Paxlovid, proved to reduce the relative risk of hospitalization or death by 89% (within three days of symptom onset) and 88% (within five days of symptom onset) compared to placebo in a trial of more than 2,000 people.
Merck’s pill, on the other hand, saw its efficacy drop from a 50% relative reduction in hospitalizations and deaths at the interim readout to just 30% in the final results. And unlike the Pfizer pill, molnupiravir is not recommended for use during pregnancy.
The news comes as two mAb treatments from Regeneron and Eli Lilly are not effective against Omicron, and supplies of a third mAb from Vir/GlaxoSmithKline are very limited.
“Though the current focus lies on SARS-CoV-2, we wish to emphasize the need for broad-spectrum antivirals for future viral outbreaks,” the preprint states. — Nicole DeFeudis
Belgium inks deals for 2 antiviral pills
As governments are moving to buy Pfizer’s antiviral pill, Belgium has reached an agreement to buy 10,000 courses, Reuters reported.
The country will also buy 10,000 courses of Merck’s molnupiravir. That drug has gone through ups and downs, with France canceling its order for the drug as recently as December after some less-than-impressive trial data. But Belgian health workers have advised that its country purchase 10,000 courses of both Paxlovid and molnupiravir.
In the US, the FDA’s antimicrobial drugs advisory committee voted 13-10 in favor of the pill’s benefits outweighing the risks for adults within 5 days of developing Covid symptoms, in November. But it took the FDA until Dec. 23 to authorize the pill.
Paxlovid requires a six pill daily regimen, with three pills in the morning and another three at night. Molnupiravir requires four in the morning and another four at night. Neither drug has been authorized by European drug agencies, though the EMA did say that it was OK to use Paxlovid for adults who don’t require supplemental oxygen. In a conversation with Reuters, the spokesperson did not reveal details about the cost of these deals. — Josh Sullivan
Pfizer’s Covid-19 pill gets OK in Britain
Pfizer’s Covid-19 pill, dubbed Paxlovid, has gotten the OK in Britain for use in adults who have mild to moderate infection and at least one underlying condition that could lead to severe illness, such as obesity, older age, diabetes mellitus or heart disease.
Because Paxlovid has shown to be most effective during the early stages of infection, the country’s Medicines and Healthcare products Regulatory Agency recommends that patients take it within five days of the start of their symptoms.
The MHRA cleared the drug on Dec. 31, adding that it’s too early to tell whether Omicron will impact its efficacy.
The pill was authorized by the FDA a couple of weeks ago. And while the agency noted in its EUA health care provider fact sheet that Paxlovid should stand up against the Omicron variant, most of the trial data has only been released in Pfizer press releases so far.
“We now have a further antiviral medicine for the treatment of COVID-19 that can be taken by mouth rather than administered intravenously,” June Raine, MHRA chief executive, said in a statement. “I hope the announcement today gives reassurance to those particularly vulnerable to COVID-19, for whom this treatment has been approved. For these individuals, this treatment could be life-saving.” — Nicole DeFeudis