Company logo of pharmaceutical company GlaxoSmithKline is seen at their Stevenage facility, Britain October 26, 2020. LONDON — Shares of British pharmaceuticals giant GSK plunged 9% Monday, after a U.S. court ruled that scientific evidence could be presented in a stack of lawsuits relating to the discontinued heartburn drug Zantac. The Delaware State Court late on Friday ruled that plaintiffs' expert witnesses could testify in the roughly 75,000 cases alleging the once-popular drug ranitidine — sold under t ...