Ambit Biosciences Initiates Quantum-R Phase 3 Trial - Quick Facts

(RTTNews) - Ambit Biosciences (AMBI) announced the initiation of the quantum-R Phase 3 clinical trial comparing quizartinib as monotherapy to chemotherapy regimens in relapsed/refractory acute myeloid leukemia or AML patients with the FMS-like tyrosine kinase-3 (FLT3)-ITD mutation.

The company stated that the trial will be conducted in FLT3-ITD positive AML patients over the age of 18 who have relapsed from, or are refractory to, frontline chemotherapy, including those patients relapsing following hematopoietic stem cell transplantation or HSCT.

The firm noted that patients will be dosed continually until disease progression or intolerable toxicity. Patients who proceed to HSCT after quizartinib treatment will be able to reinitiate treatment with quizartinib following the transplant.

The trial is expected to enroll about 326 patients in the United States, Western Europe, Canada and Australia. The primary endpoint for the Phase 3 clinical trial will be overall survival. An interim analysis will be conducted and will include an adaptive design component that will allow the Data Safety Monitoring Board (DSMB) to increase the number of patients, if warranted. Enrollment is expected to be completed in the second half of 2015, assuming there is no increase in the number of patients following the interim analysis.

The Phase 3 trial follows completion of the Phase 2 and Phase 2b clinical trials, which demonstrated the key clinical benefits of quizartinib as a monotherapy, including a high response rate in relapsed/refractory FLT3-ITD positive patients; a substantial number of patients who were bridged to a potentially curative HSCT; and median overall survival in FLT3-ITD positive patients which compared favorably to historical survival data reported for FLT3-ITD positive and negative AML patients.

Quizartinib is a once-daily, orally administered, potent and selective inhibitor of FLT3, a validated target in the treatment of AML. It is currently in development for the treatment of both newly diagnosed and relapsed FLT3-ITD positive and negative AML patients.

Both the U.S. Food and Drug Administration or FDA and European Commission have granted orphan drug designation to quizartinib for the treatment of AML.