Ariad Pharmaceuticals, Inc. announced the initiation of a phase 1 clinical trial of its investigational oral multi-targeted kinase inhibitor, AP24534, in patients with refractory haematological cancers, including those with drug-resistant forms of chronic myeloid leukaemia (CML) and acute myeloid leukaemia (AML).

This clinical study is designed to determine the safety and tolerability of AP24534, as well as its pharmacokinetics (the behaviour of the drug in patients) and its pharmacodynamics (the effects of the drug on patients' cells). Since all participants in the trial will have well-characterized malignancies, initial information describing the product candidate's anti-tumour activity will also be obtained.

This multi-centre, sequential dose-escalation trial will evaluate up to fifty patients with refractory haematological cancers, each of whom will receive a fixed oral dose of AP24534 once daily without interruption. Patients will remain on treatment until they reach predetermined endpoints.

"The start of patient enrolment in this phase 1 trial for AP24534 signals an important advance in the development of our growing portfolio of oncology product candidates," said Pierre Dodion, M.D., senior vice president and chief medical officer Ariad. "Discovered by Ariad scientists, AP24534 has been shown to selectively block a series of well-validated cancer targets known to play critical roles in the pathogenesis of several haematological cancers and solid tumours. Especially in patients with the drug-resistant forms of CML, where the genetic basis for the disease can be readily measured in individual patients, we expect this trial to provide insights into the potential therapeutic effects of AP24534 early in its clinical development."

Ariad's second oncology product candidate, AP24534, is an investigational oral multi-targeted tyrosine kinase inhibitor that has broad potential applications in cancer. In preclinical studies, AP24534 has demonstrated potent inhibition of kinase targets associated with drug-resistant chronic myeloid leukaemia and acute myeloid leukaemia, as well as angiogenesis in multiple solid tumours. AP24534 has completed extensive preclinical studies, including safety assessment studies, which indicate that the drug candidate should be well tolerated at anticipated therapeutic dose levels in cancer patients. In addition to the clinical study in haematological malignancies described above, further clinical development in patients with solid tumours is expected to begin later in 2008.