RP101 is a proprietary, first-in-class, heat shock protein 27 (Hsp27) inhibitor, administered orally.
RedHill acquired an option for RP101 from RESprotect GmbH.
In August 2014 RedHill announced that it had entered into a binding exclusive option agreement for the acquisition of the oncology drug candidate RP101 and next generation compounds.
RP101 is an orally administered, patent-protected small molecule which binds to Hsp27, a chaperone protein which is found in abnormally high levels in cancer cells, and inhibits its activity. The overexpression of Hsp27, which results in the amplification of a multidrug-resistance (MDR) gene, has been linked to tumor resistance to cytotoxic drugs and the development of metastasis. Chemoresistance limits the effectiveness of chemotherapy and can ultimately lead to treatment failure. By inhibiting Hsp27, RP101 may prevent chemoresistance and enhance the sensitivity of tumors to chemotherapy.
RP101 is based on a new mechanism of action of the anti-viral drug brivudine, a nucleoside analogue approved and marketed in several European countries for the treatment of herpes zoster. RP101 has completed several clinical studies, including Phase II studies in pancreatic cancer and has been granted Orphan Drug designation for the adjunct treatment of pancreatic cancer by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA).