GSK's Arexvy maintains its RSV market dominance, looks to key label expansion as Moderna's mRNA threat looms

Even with the threat of a potential new competitor in the respiratory syncytial virus (RSV) vaccine race on the horizon, GSK and its leading Arexvy shot aren’t sweating.

Over the first quarter, the vaccine once again came out ahead of Pfizer’s rival Abrysvo with 182 million pounds ($227 million) and some two-thirds of the RSV market share, GSK reported. In other terms, more than 70 million of the addressable U.S. population of 83 million have so far received GSK’s shot.

Pfizer, meanwhile, posted quarterly Abrysvo sales of $145 million.

It’s becoming a familiar story after the two raced to the FDA finish line last year. Since then, Arexvy has already collected blockbuster sales of 1.2 billion pounds ($1.5 billion) in its first year on the market. The company previously predicted peak sales to hit $3 billion, an estimate that GSK is “very confident” still stands, CEO Emma Walsmey said on a quarterly press call.

Still, the U.K.-based drugmaker isn’t stopping there in its Arexvy development. As Walmsey noted on the call, “There is plenty of room for growth.”

The next checkpoint is an FDA decision on the vaccine’s use in those aged 50 to 59, which would add another 50 million U.S. adults to its potential reach. The shot is currently approved for adults aged 60 and older.

That decision is expected in June and would make Arexvy the first RSV vaccine approved for the age group.

While the next couple of quarters likely won’t collect as many sales, since the RSV season typically picks up in the fall and peaks in the winter, growth over this year’s fourth quarter will be telling. By then, a third competitor—Moderna’s mRNA RSV vaccine—may have also entered the market, as its FDA decision date is set for this month.

The Arexvy maker “welcomes competition,” Walmsey said, and remains “very confident” in the underlying demand for its vaccine, Chief Commercial Officer Luke Miels added on a call with analysts.

A clearer picture on the potential impact of Moderna’s entry will come when the Center for Disease Control and Prevention’s Advisory Committee on Immunization Practices makes its immunization recommendations. That decision will begin “a race to lock down contracts” ahead of the next RSV season, Miels added.

In its Arexvy journey, GSK can look to its established shingles vaccine, Shingrix. That shot collected 945 million pounds ($1.2 billion) over the quarter, 50% of which came from global sales.

Together, the vaccines led GSK’s wider vaccine profile to 16% growth. Elsewhere, specialty medicines demonstrated similar growth of 17%, while general medicines crawled up 1%. The three sectors brought in largely even hauls of 2.3 billion pounds ($2.8 billion), 2.5 billion pounds ($3.1 billion) and 2.6 billion pounds ($3.2 billion), respectively.

All in all, the company garnered total quarterly revenues of 7.4 billion pounds ($9.2 billion) and boosted its 2024 guidance to the upper end of its 5% to 7% forecast range.