Kyowa Kirin Co., Ltd. (TSE: 4151, "Kyowa Kirin") and Kura Oncology, Inc. (NASDAQ:KURA, "Kura"))) today announced the first patient has been dosed in a Japanese Phase 2 registrational clinical trial (jRCT2031250550) studying ziftomenib, an oral menin inhibitor, for the treatment of relapsed or refractory (R/R) NPM1-mutated (NPM1-m) acute myeloid leukemia (AML). NPM1-m AML accounts for approximately 30% of AML patients. The initiation of this trial represents a significant step forward toward establishing a potential new treatment option for patients in Japan. Following completion of this clinical trial, Kyowa Kirin plans to file for regulatory approval in Japan.

Ziftomenib was approved by the U.S. Food and Drug Administration (FDA) in November 2025 for the treatment of adult patients with R/R NPM1-m AML who have no satisfactory alternative treatment options, under the brand name KOMZIFTI™.