Supplemental New Drug Application Filed for Ibrutinib (Imbruvica) for Treatment of Leukemia and Lymphoma
Treatment improves survival versus ofatumumab
A supplemental new drug application (sNDA) has been submitted to the FDA based on data from a phase III, open-label, head-to-head comparison of single-agent ibrutinib (Imbruvica, Pharmacyclics/Janssen Biotech) versus ofatumumab (Arzerra, GlaxoSmithKline) in 391 patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) who had received at least one prior therapy.
At a planned interim analysis in January 2014, the results of the phase III RESONATE trial demonstrated a statistically significant improvement in progression-free survival, the study’s primary endpoint, in patients treated with ibrutinib. Further, patients in the ibrutinib arm showed a statistically significant improvement in overall survival, a key secondary endpoint.
Data from this study will be presented at the 50th annual meeting of the American Society of Clinical Oncology (ASCO), to be held May 30–June 3 in Chicago.
The FDA granted accelerated approval for Imbruvica (ibrutinib) as a single agent for the treatment of patients with mantle cell lymphoma (MCL) or CLL who have received at least one prior therapy. The accelerated approval for these indications was based on the overall response rate in patients in phase II clinical studies. An improvement in survival or disease-related symptoms was not established in these studies.
Imbruvica (ibrutinib) is the first once-daily, single-agent, oral kinase inhibitor for patients with MCL or CLL who have received one prior therapy.
CLL is a slow-growing blood cancer of lymphocytes, most commonly B-cells. CLL is the most common adult leukemia. Approximately 16,000 patients in the U.S. are diagnosed each year with CLL. The prevalence of CLL is approximately 114,500 in the U.S. CLL is a chronic disease that predominantly occurs in the elderly, and the average age at diagnosis is 72.The 5-year survival rate is approximately 82%.
MCL is also a blood cancer; it is an aggressive type of B-cell non-Hodgkin lymphoma (NHL) that usually occurs in older adults. The disease typically involves the lymph nodes but can spread to other tissues, such as bone marrow, the liver, the spleen, and the gastrointestinal tract. The prevalence of MCL is approximately 11,300 in the U.S., and patients survive an average of 5 years.
CLL and MCL are both classified as orphan or rare diseases, defined as agents that affect fewer than 200,000 Americans. Patients commonly receive multiple lines of treatment over the course of their disease.
Ibrutinib inhibits a protein called Bruton’s tyrosine kinase (BTK). BTK is a key signaling molecule of the B-cell receptor signaling complex, which plays an important role in the survival and spread of malignant B cells. Ibrutinib blocks signals that tell malignant B cells to multiply and spread uncontrollably. It is one of the first medications to file for FDA approval via the “breakthrough therapy designation” pathway.
Source: Pharmacyclics; April 8, 2014.