FDA approves additional medical indication for Sprycel
Patients with rare type of leukemia now have another treatment option
The U.S. Food and Drug Administration today approved a new indication for Sprycel (dasatinib) for the treatment of a rare blood cancer when it is first diagnosed. The cancer, called Philadelphia chromosome positive chronic phase chronic myeloid leukemia (Ph+ CP-CML), is a slowly progressing blood and bone marrow disease linked to a genetic abnormality.
Sprycel, an oral kinase inhibitor, is believed to inhibit the activity of certain proteins responsible for the growth of cancer cells. The action allows bone marrow to begin reproducing normal red and white blood cells.
In June 2006, the FDA granted accelerated approval for Sprycel to treat adults with CP-CML with resistant disease or who were intolerant to prior therapy, including Gleevec (imatinib). The agency converted Sprycel to a regular approval in May 2009, after 24-month follow-up data from earlier clinical studies confirmed the treatment's safety and effectiveness.
Other FDA-approved drugs to treat various forms of CML include Gleevec, approved in May 2001, and Tasigna (nilotinib), approved in October 2007.
The FDA granted Sprycel a priority review for Ph+ CP-CML.
This is the third drug approved for Ph+ CP-CML under accelerated approval, a process allowing the FDA to approve a drug to treat a serious disease with an unmet medical need based on an endpoint thought to reasonably predict clinical benefit. A company is required to collect additional long term efficacy and safety information data confirming the drug's benefit. The accelerated approval program provides earlier patient access to promising new drugs while confirmatory clinical trials are being conducted.
"These drugs have dramatically changed the lives of patients with CML," said Richard Pazdur, M.D., director of the Office of Oncology Drug Products in the FDA's Center for Drug Evaluation and Research. "Results from additional CML studies continue to demonstrate the importance of studying cancer drugs in the earlier stages of a disease."
In CML, too many blood stem cells develop into a type of white blood cell called granulocytes. These granulocytes are abnormal and do not become healthy white blood cells. These cells can build up in the blood and bone marrow so there is less room for healthy white blood cells, red blood cells, and platelets. When this happens, infection, anemia, or unexpected bleeding may occur.
One open-label, randomized clinical trial in patients with CP-CML evaluated the safety and effectiveness of Sprycel. The trial measured complete cytogenetic response (CCyR) and cytogenetic response (MCyR), gene-based indicators of how well the malignant cells respond to the treatment. The most commonly reported side effects of Sprycel included decreased bone marrow activity resulting in fewer red and white blood cells and platelets (myelosuppression), fluid retention, diarrhea, headache, musculoskeletal pain, and rash.
Sprycel is marketed by New York City-based Bristol-Myers Squibb. Tasigna and Gleevec are marketed by East Hanover, N.J.-based Novartis Pharmaceuticals.