Pfizer has announced the US Food and Drug Administration (FDA) approved a supplemental New Drug Application (sNDA) to expand the indication for Bosulif (bosutinib) to include adult patients with newly-diagnosed chronic phase Philadelphia chromosome-positive chronic myelogenous leukemia (Ph+ CML). The sNDA was reviewed and approved under the FDA’s Priority Review and accelerated approval programs based on molecular and cytogenetic response rates. Continued approval for this indication may be contingent upon verification and confirmation of clinical benefit in an ongoing long-term follow up trial. Bosulif was first approved in September 2012 in the US for the treatment of adult patients with chronic, accelerated or blast phase Ph+ CML with resistance or intolerance to prior therapy.

“Bosulif was Pfizer’s first treatment for hematologic malignancies, and has since become an important treatment option for Ph+ CML patients who are resistant or intolerant to previous therapy. This expanded indication has the potential to make an even greater impact on the lives of patients with CML,” said Liz Barrett, Global President, Pfizer Oncology. “the  news marks the third FDA approval for a Pfizer hematology medicine in just five months, a significant achievement that reinforces our commitment to patients living with blood cancers.”

“Among patients with CML, with the various treatment options available, it is important to recognize the unique needs of each of my CML patients and prescribe treatments that best meet those needs,” said Jorge E. Cortes, M.D., The University of Texas MD Anderson Cancer Center. “The efficacy and distinct tolerability profile of Bosulif make it an important and useful treatment option for newly diagnosed CML patients.”

The approval was based on results from BFORE (Bosutinib trial in First line chrOnic myelogenous leukemia tREatment), a randomized multicenter, multinational, open-label Phase 3 study which showed Bosulif 400 mg was associated with a significantly higher rate of patients achieving major molecular response (MMR) at 12 months (47.2%; 95% CI, 40.9-53.4) compared to the rate achieved in patients treated with imatinib 400 mg (36.9%; 95% CI, 30.8-43.0), a current standard of care (two-sided P=0.0200). Complete cytogenic response (CCyR) rate by 12 months was 77.2% (95% CI: 72.0, 82.5) for patients treated with Bosulif compared to 66.4% (95% CI: 60.4, 72.4) for patients treated with imatinib (two-sided P=0.0075). The adverse events seen in the trial were consistent with the known safety profile for Bosulif. The most common adverse reactions in newly diagnosed CML patients treated with Bosulif (incidence =20%) are diarrhea (70%), nausea (35%), thrombocytopenia (35%), rash (34%), increased alanine aminotransferase (ALT) (31%), abdominal pain (25%), and increased aspartate aminotransferase (AST) (23%).