Pfizer Oncology racked up its third FDA approval of a new drug in 13 months as the agency green lighted leukemia drug Bosulif (bosutinib).

The drug is indicated for previously-treated Philadelphia chromosome positive chronic myelogenous leukemia (CML). The trial included patients previouisly treated with imatinib (Gleevec) or imatinib plus at least one second-generation tyrosine kinase inhibitor, and Pfizer noted that around a third of patients receiving the Novartis drug as initial therapy “do not achieve an optimal response,” while only half of those who ultimately require second-generation TKIs see good outcomes. An estimated 26,000 Americans are living with CML, and more than 5,000 new cases are diagnosed each year in the US.

“As the first therapy in our growing hematology portfolio to receive approval by the FDA, Bosulif exemplifies Pfizer’s commitment to bringing meaningful new medicines to patients with hematologic cancers,” said Pfizer Oncology VP of clinical development and medical affairs Mace Rothenberg. “We believe many doctors and CML patients will find this treatment to be a welcome addition, offering a distinct adverse event profile and a convenient once-daily dosing regimen.

FDA also approved Medivation/Astellas Pharma prostate cancer drug Xtandi (enzalutamide), indicated for treatment of metastatic castration-resistant prostate cancer that has failed treatment with Sanofi’s Taxotere. The drug was developed by Medivation but Astellas will comarket the drug in the US and has marketing rights for the rest of the world.