GSK shares have fallen the steepest since April, after the British pharmaceuticals giant reported a sharp drop in vaccine sales.

The FTSE 100 medicines titan slumped up to five per cent in early trading on Wednesday, as investors looked past the group’s higher-than-expected revenue. 

The London-based group posted a £8.9bn turnover in the third quarter, five per cent higher than last year and one per cent above analyst expectations. 

GSK’s specialty medicines are driving the group’s revenue upwards, with its injectable HIV medicines and oncology drugs each posting double-digit growth. But a two per cent dip in vaccine revenue to £2.6bn dampened the pharma giant’s performance. Sales of Arexvy, the group’s vaccine for respiratory tract disease, slumped 14 per cent to £0.2bn, offsetting a 12 per cent uplift in meningitis vaccine sales.

Chris Beauchamp, chief market analyst at investment platform IG, said weakness in GSK’s vaccine business “is pointing towards tougher trading in the coming quarters”. 

Wednesday morning’s share price dip reversed some of the stock’s gains in the first half of October, leaving GSK level in the year to date at £18.33.

Beauchamp said: “£18 still seems to be the floor for now, but GSK has to come up with some good news on core products, and soon, if it is to avoid giving back more of the 2025 share price gains.” 

Analysts at Shore Capital, which have a ‘buy’ recommendation on the stock, said GSK remains the stockbroker’s preferred asset in the UK’s pharmaceutical sector, over rival Astrazeneca. 

“We believe GSK is shedding legacy perceptions of being a perennial disappointment, and it is becoming increasingly difficult to dismiss its longer-term growth ambitions given the progress that has been made since the CHC demerger,” they said.

Chief executive Luke Miels said: “GSK has delivered another strong quarter, with our key growth drivers and new launches performing well. We remain focused on operational delivery, execution and accelerating R&D.”

Group plans staff layoffs

In July, GSK announced sweeping job cuts to fund a new £400m mega-campus in Cambridge. The firm said it would need to find £1.9bn in savings to bankroll this new site.

Cambridge is set to become the company’s new research and development home, currently based in Stevenage. Miels is hoping this move will be a shot in the arm for GSK as it races to catch up with Astrazeneca and its US peers.