SAN FRANCISCO--(BUSINESS WIRE)--Five Prime Therapeutics, Inc. (FivePrime), a leader in the discovery and development of innovative biologics announced today that it has formed a focused strategic drug discovery alliance with GlaxoSmithKline (NYSE:GSK). This new collaboration gives GSK exclusive access to FivePrime’s drug discovery platforms specifically in the areas of sarcopenia, cachexia and other skeletal muscle disorders.