GSK Plc said it will pay as much as $2.2 billion to resolve about 80,000 US court cases related to allegations that its old reflux medication Zantac was contaminated with a suspected carcinogen. The cases represent about 93% of those against the company involving Zantac,

Shares of GSK rose 6% on Thursday after the British drugmaker agreed to pay up to $2.2 billion to settle lawsuits in the United States that claimed its discontinued heartburn drug Zantac caused cancer.

GSK said it expects to take a charge of £1.8 billion ($2.3 billion) in its third-quarter results in relation to the settlements, which will be funded through "existing resources," and said there will be "no changes to GSK's growth agenda or investment plans for R&D as a result."