NEW YORK – The US Food and Drug Administration has lifted a partial clinical hold on Kura Oncology's Phase Ib trial of its menin inhibitor KO-539 in patients with relapsed or refractory acute myeloid leukemia, the company said on Thursday.
The FDA lifted the hold once the agency and Kura agreed on a strategy to mitigate differentiation syndrome, which is a potentially life-threatening adverse event seen with certain AML treatments used for remission induction. The hold went into effect in November after a patient in the trial died due to what the company believes was differentiation syndrome.
With the mitigation strategy in place, Kura will now resume screening and enrolling new AML patients into the Phase Ib portion of the Phase I/II trial, called KOMET-001. In this study, which began last June, Kura is evaluating KO-539 in relapsed or refractory AML patients, including those with NPM1 mutations or KMT2A rearrangements.
The drug demonstrated promising activity in the allcomer population in the Phase Ia dose-escalation portion of the trial. In the Phase Ib portion, the company is studying the activity of two doses of the drug and expects to enroll 12 patients with NPM1-mutant or KMT2A-rearranged relapsed or refractory AML into the two dosing cohorts. The aim is to gauge safety, tolerability, pharmacokinetics, and efficacy, and establish KO-539's recommended Phase II dose.
"We continue to be encouraged by the safety, tolerability and clinical activity observed among currently enrolled patients and look forward to sharing a comprehensive update on the Phase I study at a future medical meeting," Kura CEO Troy Wilson said in a statement.
San Diego-based Kura is also studying its drug tipifarnib in combination with Novartis' PI3K inhibitor alpelisib (Piqray) in HRAS- or PIK3CA-dependent head and neck cancer.