BETHESDA, Md.--(BUSINESS WIRE)--REGENERX BIOPHARMACEUTICALS, INC. (AMEX:RGN) (www.regenerx.com) announced today that it is seeking a strategic partner to assist in the development of RGN-457 for the treatment of cystic fibrosis (CF). RGN-457 is based on thymosin beta 4 (Tß4) peptide formulated as an inhaled therapeutic agent to address this patient population. CF is a life-threatening, hereditary disease that impairs the patient’s ability to breathe due to the accumulation of thick and sticky mucus secretions in the airways of the lungs. There are estimated to be 30,000 and 40,000 CF patients in the U.S. and Europe, respectively. It is, therefore, considered an “orphan” disease in both territories. In 2006, the predicted median age of survival for patients with cystic fibrosis was 37 years.