Despite treatment advances in AML, including potentially curative allogeneic hematopoietic stem cell transplantation (HSCT), the cornerstone of AML induction chemotherapy continues to be variations of a treatment regimen known as "7 + 3", a seven-day infusion of cytarabine and a three-day administration of an anthracycline, an approach three decades old.
Many patients respond to this initial therapy, known as induction chemotherapy, which is generally followed by additional chemotherapy, known as consolidation therapy. A significant portion of patients ultimately relapse when the disease is renewed by a subpopulation of quiescent leukemic stem cells which lie dormant in the bone marrow stroma. This AML therapeutic regimen is associated with very significant short-term toxicity and with frequent development of life-threatening complications and occasional deaths during therapy.
Cantex conducted an open-label, non-randomized Phase IIA pilot clinical trial of CX-01 in 12 patients with newly diagnosed AML. Of these 12 patients, 11 had no prior illness that predisposes to leukemia. These 11 primary AML patients received CX-01 in combination with standard induction chemotherapy. All 11 patients achieved a complete response with a single cycle of this treatment. A 12th patient, with pre-existing chronic myelomonocytic leukemia, did not have a complete response with a single induction cycle, but achieved a complete remission with a second induction cycle without CX-01. These results suggest that CX-01 may enhance the complete remission rate in patients receiving chemotherapy for primary AML.
Cantex is now enrolling patients into a 75-patient, U.S.-based, multiple arm randomized Phase IIB clinical trial in newly diagnosed patients with both primary and secondary AML, administering CX-01 in conjunction with the standard induction and consolidation chemotherapy. Endpoints of the clinical trial include the effect of the addition of CX-01 to induction and consolidation chemotherapy on the incidence and duration of complete remission, on platelet and white blood cell recovery, and on overall survival. Cantex anticipates top-line results from this clinical trial in the first half of 2018.