The FDA issued an expanded indication for ibrutinib (Imbruvica; Pharmacyclics) for the treatment of patients with CLL who have a deletion in chromosome 17 (17p deletion), which results in poor response to standard CLL therapies. Earlier in the year, the FDA approved ibrutinib for all patients with CLL, after having designated it as a breakthrough therapy.
With this new indication, the FDA also approved new labeling for the drug to reflect that the clinical benefit of ibrutinib for the treatment of CLL has been verified based on new clinical trial results. These results confirmed the PFS and overall survival (OS) benefits associated with ibrutinib.
The expanded indication for patients with 17p deletion is based on results from a clinical trial of 391 previously treated patients with CLL; of these, 127 patients had CLL with 17p deletion. Patients were randomized to ibrutinib or to ofatumumab until disease progression or until side effects became intolerable.
The trial was stopped early after a preplanned interim analysis showed that patients receiving ibrutinib had a 78% PFS improvement and a 57% OS benefit. Among the 127 patients with CLL plus 17p deletion, those receiving ibrutinib had a 75% improvement in PFS.
The most common side effects associated with ibrutinib were thrombocytopenia, neutropenia, diarrhea, anemia, fatigue, musculoskeletal pain, upper respiratory tract infection, rash, nausea, and fever.
This new indication was approved under the FDA’s accelerated approval and was reviewed under the agency’s priority review program. (July 28, 2014)
