Drugs giant GSK's shares dive after sales of its bestselling shingles jab slump on weak demand in China

GSK's London-listed shares fell as much as 7% on Wednesday after third-quarter results showed demand for its shingles vaccine Shingrix — the company's bestselling product — weakening sharply, particularly in China. Vaccine sales across the group dropped 2% to £2.6 billion in the three months to September 30. A looming patent loss on a blockbuster HIV drug added to investor unease, offsetting a 3% gain in overall operating profit driven by older medicines.

A 7% intraday drop would be GSK's worst single-day fall since June 2024, wiping out all of this year's earlier share gains.

Falling demand for Shingrix and its RSV jab dragged vaccine revenue down despite stronger specialty medicines performance elsewhere in the portfolio.

GSK is now pressing to cut costs and accelerate its drug pipeline as patent expiry on its HIV treatment threatens a key future revenue stream.