EMA grants Orphan Drug Designation to pracinostat for the treatment of AML

On 11^th January 2018, the European Medicines Agency’s (EMA)  Committee for Orphan Medicinal Products (COMP) granted Orphan Drug Designation to pracinostat, for the treatment of Acute Myeloid Leukemia (AML).¹ Pracinostat is an oral Histone Deacetylase (HDAC) inhibitor with significant antineoplastic activity against a wide variety of tumor cell lines, including leukemia cells.^2,3

The Orphan Drug Designation granted for pracinostat by the EMA COMP was based on data from a phase II open-label, single-arm, multicenter study (NCT01912274), which assessed the safety and efficacy of pracinostat in combination with azacitidine (AZA) in patients (aged ≥ 65 years) with newly diagnosed AML who are ineligible for chemotherapy. Findings from this study showed that pracinostat in combination with AZA led to a median Overall Survival (OS) of 19.1 months and a Complete Remission (CR) rate of 42% in patients (n = 50). The data from this phase II study compared favourably with historical single-agent AZA data in similar AML population.⁴

Currently, pracinostat is being evaluated in a pivotal randomized phase III study (NCT03151408) in combination with AZA in patients with newly diagnosed AML who are unfit for standard induction chemotherapy. The primary endpoint of the study is OS. The secondary endpoints include morphologic CR rate, cytogenetic CR and CR without minimal residual disease. Helsinn and MEI Pharma, the drug manufacturers, announced in August 2017 that the “first patient has been dosed in this pivotal study”.¹