NEW YORK (AP) — Onyx Pharmaceuticals Inc. and partner Bayer ended a late-stage study of its drug Nexavar in skin cancer patient because the drug was not working to improve patients' overall survival rate. The companies said an independent data monitoring committee concluded the drug would not meet its treatment goal of improved overall survival in patients. Late-stage studies are typically the largest and most expensive stage of development for a drug candidate. Nexavar is already approved to treat liver and advanced kidney cancer. Germany-based Bayer and Emeryville, Calif.-based Onyx said they will further review the findings of the skin cancer study to determine if the data has any impact on other ongoing Nexavar studies.