The FDA ( Food and Drug Administration ) has approved a new indication for Tasigna ( Nilotinib ) 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.

Tasigna is believed to work by blocking a signal that leads to leukemic cell development. The new indication expands the use of Tasigna to adult patients in earlier stages of the disease. The FDA originally approved Tasigna in October 2007 for the treatment of Ph+CP-CML in adult patients whose disease had progressed or who could not tolerate other therapies, including Imatinib ( Gleevec ).

When Tasigna was originally approved in October 2007, the FDA identified that the therapy placed patients at risk of an abnormal heart rhythm called QT prolongation. In March 2010, the FDA approved a Risk Evaluation and Mitigation Strategy ( REMS ) for Tasigna to help patients and health care professionals to better understand this risk. The REMS includes an updated Medication Guide and a communication plan to help reduce medication errors involving drug-food interactions and incorrect dosing intervals.

In chronic myeloid leukemia, 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.

The FDA granted Tasigna a priority review for Ph+ CP-CML. The agency completed the review in six months. The new indication for Tasigna was approved under the FDA’s accelerated approval program, which allows FDA to approve a drug to treat serious diseases with an unmet medical need based on an endpoint thought to reasonably predict clinical benefit. The 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 the confirmatory clinical trials are being conducted.

The safety and effectiveness of Tasigna were evaluated in a single clinical trial enrolling 846 patients with newly diagnosed Ph+ CP-CML. Patients received either Nilotinib or Imatinib until the disease worsened, or until unacceptable side effects developed. The study was designed to measure a significant reduction in the surrogate endpoint of the number of CML cancer cells in the blood stream ( i.e., major molecular response ) at 12 months. About 44% of patients who received Tasigna experienced a major molecular response, compared with 22% of patients receiving Imatinib.

In patients with newly diagnosed CP-CML, the most commonly reported non-blood-related adverse drug reactions were rash, itching, headache, nausea, fatigue, and muscle pain. Serious blood-related drug reactions included myelosuppression, thrombocytopenia, neutropenia, and anemia.

Other FDA-approved drugs to treat chronic myeloid leukemia include Gleevec in May 2001 and Sprycel ( Dasatinib ) in June 2006.

Source: Fda, 2010

XagenaMedicine2010