Thanks to the FDA’s expedited reviews, an RSV prevention market battle between several pharma giants may kick off in 2023.
AstraZeneca and Sanofi will learn about the FDA’s verdict for their RSV antibody drug nirsevimab in the third quarter of 2023, the companies said Thursday. European regulators already cleared the RSV preventative therapy under the brand name Beyfortus in early November.
Previously, Pfizer and GSK separately earned FDA priority reviews for their RSV vaccines, with decisions for both expected in May 2023. As for the Sanofi and AZ antibody, the FDA “has indicated it will work to expedite its review,” the companies said Thursday. This means, if approved on time, the three products might be able to launch into the 2023-24 RSV season together.
Still, nirsevimab is targeting a different treatment setting—at least initially.
AZ and Sanofi are seeking approval for nirsevimab to prevent RSV disease in newborns and infants in their first RSV season and for children up to 2 years who remain vulnerable to severe RSV disease during their second RSV season.
By comparison, Pfizer and GSK are initially angling their vaccines for adults ages 60 years and older. Both Pfizer’s RSVpreF (PF-06928316) and GSK’s RSVPreF3 are recombinant vaccines targeting the viral fusion protein that RSV uses to enter human cells, but the GSK version is also boosted with GSK’s AS01E adjuvant.
Despite a difference in their initial target markets, Pfizer looks on track to tread on AZ and Sanofi’s desired turf. In November, Pfizer unveiled partly positive interim data for RSVpreF to protect newborns when used as a maternal immunization.
Each year, more than 177,000 older adults are hospitalized in the U.S. alone because of RSV, and RSV affects more than 6.5 million infants under six months old globally each year, according to Pfizer. Together, the two indications represent a potential multibillion-dollar peak sales opportunity, Pfizer CEO Albert Bourla said during the company’s third-quarter earnings call in November. SVB Securities analyst Geoffrey Porges in 2021 put the RSV market value at $10.5 billion by 2030.
If approved and recommended by the CDC, a vaccine like Pfizer’s RSVpreF holds an advantage of zero out-of-pocket copay, Bourla noted. AZ and Sanofi’s nirsevimab will likely come with out-of-pocket cost, but the antibody drug’s seemingly higher efficacy for all medically attended RSV infections in infants could be a key selling point, SVB Securities analysts pointed out in a November note.
Meanwhile, GSK appears stalled on the maternal vaccination front. The British pharma in February 2022 paused its maternal RSV vaccine trials after an independent data monitoring committee noted a safety concern. A company spokesperson said that the safety analysis “is ongoing as we continue to focus on delivering a potentially best-in-class RSV vaccine for older adults.”
Still, the GSK vaccine’s high efficacy data in older adults could mean blockbuster sales by itself. The GSK shot could reach $1.8 billion sales in 2028, Evaluate Vantage projected in its annual world preview report published in December.
Meanwhile, more potential RSV rivals are on their way. Moderna is expecting interim analysis for its mRNA vaccine candidate, mRNA-1345, in older adults this winter, CEO Stéphane Bancel confirmed to Fierce Biotech earlier this week.
Elsewhere, Bavarian Nordic expects topline data for its RSV vaccine candidate in adults at least 60 years of age in mid-2023. Johnson & Johnson launched a phase 3 trial of its RSV vaccine also in individuals 60 years of age and older in September 2021. Separate from nirsevimab, Sanofi is working on a live-attenuated RSV shot with phase 2 data in infants and toddlers expected in April 2024.