FDA Agrees to Review Ponatinib for Treatment-Resistant Leukemia
Decision expected in March 2013 (Oct. 24)
The FDA has accepted a New Drug Application (NDA) for accelerated review of the investigational BCR-ABL inhibitor ponatinib (Ariad Pharmaceuticals) in patients with resistant or intolerant chronic myeloid leukemia (CML) or Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL).
The FDA also has granted the manufacturer’s request for priority review, which is given to investigational medicines that have the potential to provide significant improvement in the treatment, prevention, or diagnosis of a disease.
The agency set an action date of March 27, 2013.
Ponatinib is an investigational BCR-ABL inhibitor that has also selectively inhibited other tyrosine kinases in preclinical studies, including FLT3, RET, KIT, and members of the FGFR and PDGFR families of kinases.
The primary target for ponatinib is BCR-ABL, an abnormal tyrosine kinase that is expressed in CML and Ph+ ALL. The drug also targets BCR-ABL isoforms, which carry mutations that confer resistance to treatment with existing tyrosine kinase inhibitors, including the T315I mutation, for which no effective therapy exists.
CML is characterized by excessive, unregulated production of white blood cells (WBCs) by bone marrow due to a genetic abnormality that produces the BCR-ABL protein. After a chronic phase of production of too many WBCs, CML typically evolves to a more aggressive phase, referred to as the accelerated phase or blast crisis. Ph+ ALL is a subtype of acute lymphoblastic leukemia that carries the Philadelphia (Ph) chromosome, which produces BCR-ABL. Ph+ ALL has a more aggressive course than CML and is often treated with a combination of chemotherapy and tyrosine kinase inhibitors. Since both of these diseases express the BCR-ABL protein, both are potentially susceptible to treatment with ponatinib.
Source: Ariad Pharmaceuticals, October 24, 2012.