FTSE 100 declines as GSK shares fall after Nuvalent acquisition announcement

Tuesday 09 June 2026 - 10:00

The UK’s main stock index, the FTSE 100, edged lower on Tuesday as shares in pharmaceutical group GSK weighed on market performance following the announcement of a major overseas acquisition.

GSK revealed plans to acquire U.S.-based drug developer Nuvalent in a deal valued at approximately $10.6 billion. The move is aimed at strengthening the company’s oncology portfolio, particularly in lung cancer treatments. However, investors reacted cautiously, sending GSK shares down by around 2.8 percent.

The decline in GSK stock contributed significantly to losses in the broader healthcare sector, with the FTSE 350 Pharmaceuticals and Biotechnology index also falling as investors reassessed the financial impact of the acquisition.

Overall, the FTSE 100 slipped around 0.3 percent, while the mid-cap FTSE 250 managed a slight gain, reflecting mixed sentiment across UK equity markets.

Market analysts noted that global investors are closely watching geopolitical developments, particularly tensions in the Middle East, which have influenced energy prices and inflation expectations. Concerns over higher energy costs have reinforced expectations that the Bank of England could consider further interest rate adjustments in the coming months.

Oil major BP also traded lower, tracking weaker crude oil prices amid easing geopolitical tensions. At the same time, investors reacted to internal governance developments within the company following leadership changes at board level.

Despite broader market weakness, some stocks posted strong gains. Investment firm Molten Ventures saw its shares rise sharply after reporting positive annual results, while beverage company Fever-Tree benefited from strong revenue expectations and a new share buyback program.

Homebuilder MJ Gleeson, however, declined after issuing profit guidance below market expectations, highlighting ongoing pressure in the UK housing sector.

The mixed performance across sectors underscores the current volatility in UK markets, where corporate earnings, interest rate expectations and geopolitical risks continue to shape investor sentiment.