GlaxoSmithKline PLC, which replaced the head of its struggling U.S. operations in February, is considering changes to its compensation model for sales staff, according to an internal memo obtained by Bloomberg News. A task force is looking at "more comprehensive options to simplify the Patient First program" for incentive pay and will provide a report within a month, Glaxo, based in London, said in an April 1 statement to its U.S. sales employees.