FTSE rises, GSK tumbles after Zantac decision opens legal floodgates

The FTSE 100 rose on Monday morning despite GSK (GSK) collapsed after a US court ruling opened the door to thousands of lawsuits against its allegedly carcinogenic heartburn treatment Zantac.

The pharmaceutical giant fell 9.3% to £15.99 after a Delaware judge gave the green light for 70,000 cases to proceed and allowed expert witnesses to testify in court that the drug can cause cancer .

Investors had reached a point of some comfort with GSK’s Zantac problem as a series of US lawsuits linking the heartburn drug to cancer appeared to be winding down. However, the new ruling throws a significant wrench into the works, said AJ Bell chief investment officer Russ Mould.