RegeneRx Biopharmaceuticals, Inc. (RegeneRx Biopharmaceuticals) is publicly held US based biopharmaceutical company. The company is engaged in the research and development of new pharmaceutical products towards the treatment of human diseases resulting from immune system disorders. It treats various diseases including cancer, chronic viral infections and auto immune diseases. The key product candidates developed by the company are currently in various stages of development. The candidates include: RGN-137 (topical); RGN-259 (eye drop); RGN-352 (injectable) and RGN-457 (inhalation). It is principally concentrated on the commercialization of Thymosin beta4, a 43 amino acid peptide, used in the treatment of injured tissues and non healing wounds. Moreover, it is involved in development of Tß4, Tß4 peptide fragments for assisting cosmeceutical applications. The company is headquartered in Bethesda, Maryland, the US.