Otsuka Pharmaceutical Co., Ltd.

Pharmaceuticals
June 7, 2019

Otsuka and its Subsidiary Astex Pharmaceuticals, Inc. Announce Positive Results from a Phase III Clinical Trial of Anticancer Candidate ASTX727

Clinical activity and safety similar to that observed in a previous phase 1/2 study in myelodysplastic syndrome (MDS)

The oral, fixed-dose-combination drug candidate ASTX727 comprises the active ingredient of the DNA methylation inhibitor Dacogen® (decitabine) in combination with the novel metabolic enzyme inhibitor cedazuridine that suppresses the degradation of decitabine. Phase III trials are underway in the U.S. and Canada to support what would become the first-ever oral DNA methylation inhibitor, contingent on regulatory approval.

This trial was a multicenter, randomized, open-label, crossover study of ASTX727 and decitabine IV for untreated, mid-to-high-risk MDS patients aged 18 years and older. Subjects took ASTX727 in tablet form once daily for five days, stopped for 23 days to complete the 28-day cycle, then received decitabine in a once-daily infusion for five days as part of a second 28-day cycle--or the converse order. Following completion of these first two cycles, ASTX727 was administered to both groups in 28-day cycles until disease progression or any other reasons for discontinuation.

The trial met its primary endpoint of decitabine exposure equivalence of five-day dosing of oral ASTX727 (100 mg of cedazuridine and 35 mg of decitabine), in comparison to IV decitabine administered at the approved daily dose of 20mg/m2 in a one-hour infusion.