RSV antibody from Sanofi and AstraZeneca approved in Europe

With the first vaccines to guard against respiratory syncytial virus (RSV) expected to receive regulatory approval in the months ahead, the European Commission earlier this month gave its nod to a monoclonal antibody developed by Sanofi and AstraZeneca to prevent RSV lower respiratory tract illness (LRTI) in newborns and infants. The EC’s approval of the drug, Beyfortus (nirsevimab), is based on a series of clinical trials, including Phase 3 trials, and follows the recommendation in September of the European Medicines Agency’s Committee for Medicinal Products for Human Use.

RSV, the most common cause of bronchiolitis, pneumonia, and other respiratory infections in infants, is currently surging. The US Centers for Disease Control and Prevention reported case counts in October that were well over twice those of a year earlier. Beyfortus is the first single-dose RSV preventative for infants, including those born preterm.

Sanofi and AstraZeneca announced a joint development agreement for Beyfortus in 2017 under which AstraZeneca leads development and manufacturing activities and Sanofi is responsible for commercialization.

The news comes as front-runners in the race for an RSV vaccine marked advances. GSK announced earlier this month that the US Food and Drug Administration has accepted a biologics license application (BLA) and granted priority review for its older-adult RSV vaccine candidate, RSVPreF3. A decision is expected in May. Meanwhile, Pfizer this month announced positive results from a Phase 3 clinical trial investigating its bivalent vaccine candidate, RSVpreF, when administered to pregnant people to protect infants from RSV disease after birth.

In August, Pfizer announced positive results from a Phase 3 trial evaluating RSVpreF in adults 60 and older. Pfizer says that because of the results of the more recent trial, it plans to submit a BLA to the FDA by year-end.

Consulting firm Evaluate forecasts Beyfortus sales of just over $1 billion by 2028, according to Cem Baydar, chief consulting officer at the London-based firm. But he says the size of the market for RSV therapies is difficult to estimate.

“The more traditional vaccines from GSK and Pfizer have yet to be approved, although [they] have blockbuster potential,” Bayder says in an email response to questions.