GlaxoSmithKline plc. (ADR) (NYSE:GSK) stock has gone up 7.48% since the release of its higher-than-expected second quarter fiscal '15 (2QFY15) earnings on July 29. The stock rallied, despite an over 1% decline on the NYSE ARCA Pharmaceutical Index (DRG). Bidness Etc look at the reasons behind the company's recent stock gain.