FDA advisers recommend Novavax COVID vaccine for emergency use

Gloved hand, vaccine vial, and vaccination card
Gloved hand, vaccine vial, and vaccination card

Diverse Stock Photos / Flickr cc

With nearly 22% of the nation yet to receive a single COVID-19 vaccine dose, federal vaccine advisers today recommended that the Novavax COVID-19 vaccine be approved under an emergency use authorization (EUA).

If the Food and Drug Administration (FDA) accepts the group's recommendation and Centers for Disease Control and Prevention (CDC) advisers recommend it, Novavax would give the United States a fourth vaccine to battle the virus. The Novavax vaccine is already approved for emergency use in other countries, and US officials hope that a vaccine made with a more traditional process might sway some who have been hesitant to be immunized against COVID-19.

In other US developments, the CDC today said the BA.4 and BA.5 Omicron subvariants are starting to become more prevalent across the country, and a new survey of US public schools found that rural and lower income schools were less likely than others to make ventilation improvements to reduce the spread of COVID-19.

Uncertainty about Omicron protection, heart effects

During today's meeting, the Vaccines and Related Biological Products Advisory Committee (VRBPAC) was asked to weigh the benefits and risks in people ages 18 and older. The Novavax vaccine is a recombinant nanoparticle protein-based product that contains an adjuvant. It is given in two doses, 3 weeks apart. The measure passed with 21 yes votes and 1 abstention.

Ahead of the meeting last week, FDA staff published an extensive review of the vaccine's efficacy and safety, which said the vaccine—largely studied when the Alpha variant was circulating—would probably provide meaningful protection against the Omicron variant, though they raised concerns for rare cardiac conditions after vaccination, similar to ones that have been seen with other COVID-19 vaccines.

During today's discussion, the group aired reservations about potential rare cardiac complications from COVID-19 vaccines and pushed for the need to explore the underlying mechanism. Many also agreed that the efficacy profile looked similar to earlier approved mRNA vaccines, and some noted the benefits of a different vaccine that has easier storage requirements and less reactogenicity for those who are sensitive to mRNA vaccine side effects.

The abstention came from Bruce Gellin, MD, MPH, chief of global public health strategy at the Rockefeller Foundation, who is a temporary VRBPAC voting member. He said his abstention should be interpreted as a conditional yes vote. He praised the company's perseverance with the vaccine and said its data are impressive. But he said there are still questions about cross-protection in Omicron settings and expressed confidence that FDA staff will evaluate more data than VRBPAC saw before making its final recommendation.

At today's meeting, Filip Dubovsky, MD, MPH, Novavax's senior vice president and chief executive officer, said the company expects in the coming months to seek clearances for expanded age indications and use as a booster dose.

BA.4 and BA.5 make US inroads

In its weekly update on variant activity, the CDC today said the BA.4 and BA.5 Omicron subvariants now make up 5.4% and 7.2% of sequenced samples, respectively, with the viruses present in all parts of the country.

Last week, the two subvariants were under the threshold of 1% and weren't listed separately. The two subvariants were first detected in South Africa, where they fueled a modest fifth wave of activity after Easter. Though BA.4 and BA.5 were first detected by South African scientists, it's not clear where they originated.

Meanwhile, the CDC said the level of the dominant BA.2.12.1 subvariant, first seen in New York, continued to rise and is at 62.2% of sequenced samples, up a bit from 59.2% last week.

The new variants are known to be more transmissible and are thought to have immune evasion properties, but so far, there is no sign that they cause more severe disease.

Ventilation, Paxlovid, and kids' cases

In other US COVID developments:

  • A CDC survey of US public schools on ventilation improvement strategies found that few used higher-cost strategies, such as upgrading ventilation systems or using air filtration systems. The group published its findings today in Morbidity and Mortality Weekly Report (MMWR). The most common lower-cost strategies included holding activities outdoors, inspecting ventilation systems, and opening doors and windows. Rural and mid-poverty-level schools were less likely to take the more resource-intensive steps. The web survey began in the summer of 2021.

  • Pfizer yesterday announced that it would invest $120 million to boost production of Paxlovid, its SARS-CoV-2 antiviral, at its Michigan plant, because of strong demand.

  • Pediatric COVID-19 cases declined for the first time since early April, the American Academy of Pediatrics (AAP) said in its weekly update. More than 87,000 cases were reported for the week ending Jun 2, though it's not clear if the Memorial Day weekend affected testing levels.

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