The European Medicines Agency (EMA) has granted Helsinn Group and MEI Pharma Inc (NASDAQ: MEIP) Orphan Drug Designation for the investigational drug candidate pracinostat, which is currently in a Phase 3 study in combination with azacitidine for the treatment of acute myeloid leukaemia (AML) in adult patients unfit to induction chemotherapy, the Swiss pharmaceutical group disclosed on Thursday.

The EMA's decision was based on the scarcity of treatments available to those suffering from AML and on positive results from a Phase 2 study that were presented at the American Society of Hematology (ASH) Annual Meeting in December 2016.

EMA Orphan Drug Designation status is assigned to medicines intended for use against a rare condition in the EU and it allows pharmaceutical companies to benefit from incentives to develop a medicine for a life-threatening or chronically debilitating rare disease.

Helsinn and MEI Pharma announced in August 2017 the dosing of the first patient in the pivotal Phase 3 study investigating pracinostat in combination with azacitidine in adults with newly diagnosed AML who are unit to receive intensive induction chemotherapy. The primary endpoint is overall survival and secondary endpoints include morphologic complete remission (CR) rate, cytogenetic complete remission, and complete remission without minimal residual disease.

Results from a Phase 2 open-label, single-arm, multicentre study of the combination therapy involving 50 patients with newly diagnosed AML not eligible for induction chemotherapy showed a median overall survival of 19.1 months, one-year survival of 62%, and a CR rate of 42%.