Kura's leukemia treatment performs best when tacked onto existing combo, new data show

New data from Kura Oncology’s phase 1b trial show that the company’s oral leukemia treatment performed best on top of a standard-of-care combo regimen in newly diagnosed patients with specific mutations. 

It was a small sample, but the company reported Tuesday that all five enrolled patients who had recently been diagnosed achieved a complete response when given ziftomenib on top of the chemotherapies cytarabine and daunorubicin. The original combo is approved for newly diagnosed patients with secondary acute myeloid leukemia. Kura is aiming ziftomenib at patients with NPM1-mutant (NPM1-m) and KMT2A-rearranged (KMT2A-r) acute myeloid leukemia.

Kura also tested ziftomenib on top of AbbVie's Venclexta and the chemotherapy azacitidine in 15 other patients, recording a 53% overall response rate, with variations depending on the mutation or whether or not patients had previously received a menin inhibitor. As of the data cutoff, 16 out of 20 patients remained enrolled in the trial. 

The biotech says a 200 mg, once-daily regimen of ziftomenib was well tolerated with “the safety profile consistent with features of underlying disease and backbone therapies,” according to a release. Amer Zeidan, primary investigator of the study, interim chief of the Division of Hematologic Malignancies and director of early hematology therapy research at the Yale Cancer Center, called ziftomenib “one of the most exciting investigational agents being studied in AML.” 

“The combinations demonstrate encouraging preliminary evidence of clinical activity in patients with refractory/relapsed disease after failure of other agents, including venetoclax, a setting with very limited effective treatment options,” Zeidan said in a statement.

Just to even have data to report could be seen as a win for Kura, two years after ziftomenib was freed from a partial clinical hold following a patient death. Last week, the company conducted a $150 million private placement, expected to finance operations into 2027. 

Front and center remains the company’s ongoing phase 2 trial testing ziftomenib as a monotherapy in patients with NPM1-mutant acute myeloid leukemia, with enrollment expected to wrap up by the middle of the year. 

Investors appeared to appreciate the early signs of benefit in the combo trial as well, with Kura’s shares up 11.88% just before the market opened, from $18.60 to $20.81.