July 31, 2023: On Wednesday, GlaxoSmithKline CEO Emma Walmsley said she hopes slow takes for the group’s RSV vaccine to start slower than it did for its previous shingles shot.

“I think the uptake on this we need to watch for through the seasons, it won’t be the same speed of build but we do think it’s a key pillar and contributor,” Walmsley said during a call with journalists.

She spoke about the respiratory syncytial virus vaccine after London-based GSK reported second-quarter earnings and revenue topped Wall Street’s estimates.

Previous month, GSK’s RSV shot became the first to win U.S. and European Union approval for treating adults 60 and older. The company is preparing to roll out the vaccine this fall; the common respiratory disease typically begins to spread at higher levels in the autumn.

RSV usually causes mild, cold-like symptoms, but it kills thousands of seniors and hundreds of children each year in the U.S.

The company has not provided estimates for how much revenue the RSV shot will rake this year after its launch. But GSK’s full-year forecast expects overall vaccine revenue to increase by a “mid-teens” percentage from last year.

Walmsley also noted that GSK expects the vaccine to generate around 3 billion pounds, or $3.87 billion, in sales “over time.”

The company’s top-selling drug is GSK’s vaccine against shingles, a viral infection that results in a painful rash. The shot generated second-quarter sales of 880 million pounds, or $1.14 billion, and has been a critical revenue driver since it launched in the U.S. in late 2017.

The shot, called Shingrix, won more than 90% of the U.S. market share for shingles vaccines just five months after its launch.

In 2018, the shot gained approval in the European Union, Japan, and Canada, among other countries, and posted full-year global sales of 784 million pounds, or $1.01 billion.

Investors hope that GSK’s RSV shot will help offset patent ends for some of the company’s blockbuster HIV drugs in some years. Those expirations will permit other drugmakers to launch similar and potentially cheaper versions of those medications.