PLYMOUTH MEETING, Pa.--(BUSINESS WIRE)--Beijing Med-Pharm Corporation (Nasdaq: BJGP) today announced that it has reached an agreement with Sunstone Pharmaceutical Co., Ltd. (“Sunstone”) to acquire a minority stake in the company. Sunstone is a privately held manufacturer of primarily over-the-counter (OTC) medicines, with operations in Tangshan, Hebei Province, People’s Republic of China.