The US Food and Drug Administration (FDA) has expanded the indication for Pfizer’s respiratory syncytial virus (RSV) vaccine Abrysvo to include adults aged 18–59 years who have chronic conditions that place them at increased risk of lower respiratory tract disease caused by the virus.
The label expansion adds to the existing label for Abrysvo that allows for vaccine use in adults over 60 years of age and pregnant women (between 32 and 36 weeks of gestation). The approval comes just in time for the current RSV season in the US, which typically runs from October to April.
Abrysvo generated $515m in sales in the fourth quarter of last year, as per Pfizer’s financials. While these are nowhere close to the profits Pfizer saw with products such as its Covid-19 vaccine developed with BioNTech, and the antiviral treatment Paxlovid, at their peak, with weakening demand for the Covid-19 products, Pfizer has touted Abrysvo as one of the primary revenue driver.
Abrysvo’s main competitor is GSK’s Arexvy, which is approved in the same indication. However, its use is limited to adults over 50 years of age. Arexvy raked in $1.2bn in sales last year, as per GSK’s financials.
GlobalData expects Arexvy to have higher sales of $3.3bn in 2030, compared to $2.2bn of Abrysvo over the same period. GlobalData is the parent company of Pharmaceutical Technology.
The FDA approval of the indication was based on the positive data from the Phase III MONeT study (NCT05842967). The trial was divided into two substudies; substudy A, which evaluated Abrysvo in patients with chronic medical conditions, including asthma and diabetes; and substudy B, which investigated the vaccine in immunocompromised patients.
Pfizer has not disclosed detailed results from the trial, stating its intention to publish these in a peer-reviewed scientific journal and present the same at a scientific conference. In August, the company reported that a single 120µg dose of the vaccine led to “strong neutralising” responses against RSV-A and RSV-B. The commonly reported treatment-associated side effects were pain at the injection site, muscle pain, joint pain and nausea.
Pfizer is also evaluating Abrysvo in children aged between two and 17 years in an open-label Phase I PICASSO trial (NCT05900154). The trial enrolled 128 participants across the US, according to ClinicalTrials.gov.
