NEW YORK (
announced separate plans Monday to move respective blood cancer drugs into pivotal clinical studies that, if positive, could lead to regulatory approvals.
Ariad said it is ready to begin a pivotal, phase II study of ponatinib, previously known as AP24524, in patients with resistant or intolerant chronic myeloid leukemia (CML) and so-called Philadelphia positive acute lymphoblastic leukemia (ALL).
Ponatinib becomes the second Ariad drug to enter into a late-stage study. The company's lead drug ridaforolimus is in an ongoing phase III study of sarcoma patients, partnered with Merck.
The phase II study of ponatinib will enroll 320 patients, all who have cancer that no longer responds to treatment with Sprycel or Tasgnia marketed by
CML is characterized by an excessive and unregulated production of white blood cells by the bone marrow due to a genetic abnormality that produces a protein known as BCR-ABL. Philadelphia-positive ALL patients also carry a genetic abnormality produces BCR-ABL. Novartis' Gleevec was the first drug approved to work by "repairing" the genetic error in CML patients. Despite that medical breakthrough, many CML patients relapse when their tumors mutate or become resistant.
Ponatinib is a pill designed to inhibit the production of the BCR-ABL protein and be effective in patients who have no other treatment options. This is why Ariad believes it will be able to seek regulatory approval based on positive results from a single arm phase II study with a tumor response as the primary endpoint.
Ariad is going ahead with the single arm phase II study of ponatinib study without a Special Protocol Assessment (SPA) agreement from the U.S. Food and Drug Administration. A company spokeswoman said the study was designed with input from regulatory authorities but an SPA was not necessary because ponatinib is following a clinical and regulatory path already carved out successfully by Bristol-Myers and Novartis.
The pivotal study of ponatinib is expected to enroll fully by the end of 2011, Ariad says.
Meantime, Cyclacel also said Monday it reached agreement with the FDA on an SPA agreement which will let the company begin a phase III study of sapacitabine in elderly patients with acute myelogenous leukemia (AML).
Cyclacel first engaged the FDA in SPA discussions for this study in the first quarter, leading some investors to grumble about the long wait. Nonetheless, the agreement will allow Cyclacel to begin the sapacitabine study before the end of the year, in line with the company's guidance.
The sapacitabine study will enroll newly diagnosed AML patients aged 70 years or older who are not able to tolerate intensive chemotherapy. Patients will be randomized to receive either sapacitabine, a pill, or an active control treatment. The primary endpoint of the study is overall survival.
Also on Monday,
announced that its experimental AML drug lintuzumab failed to prolong survival in a phase III study.
--Written by Adam Feuerstein in Boston.
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