The US Food and Drug Administration (FDA) has accepted for filing Pharmacyclics, Inc.'s supplemental New Drug Application (sNDA) to support the review of Imbruvica (ibrutinib) in the treatment of patients with chronic lymphocytic leukaemia (CLL) and small lymphocytic lymphoma (SLL) who have received at least one prior therapy for a full approval.
The sNDA was submitted to the FDA based on data from the randomized, multi-center, open label phase III RESONATE trial, PCYC-1112-CA, a head-to-head comparison of Imbruvica versus ofatumumab in 391 patients with CLL or SLL who had received at least one prior therapy. The target date as defined by the Prescription Drug User Fee Act by which the FDA is planning to finalize the review of this application (PDUFA date) is October 7, 2014.
"We are pleased to have received the acceptance of our sNDA filing by the FDA. We believe the data set that we have submitted is compelling," said Dr. Urte Gayko, senior vice president of Global Regulatory Affairs, Pharmacyclics. "We look forward to continuing to work with the FDA as they complete their review of this application."
RESONATE is a phase III, multi-center, international, open-label, randomized study that examined Imbruvica versus ofatumumab in patients with previously treated CLL/SLL who had received at least one prior therapy and were not considered appropriate candidates for treatment or retreatment with a purine analog (n=391). Patients received either 420 mg oral Imbruvica (n=195) once-daily until progression or unacceptable toxicity or received intravenous ofatumumab for up to 24 weeks (n=196, initial dose of 300 mg followed by 11 doses at 2,000 mg, per dose and schedule consistent with local labeling).
In January 2014, the RESONATE study was stopped early following the unanimous recommendation by the study's Independent Data Monitoring Committee (IDMC) after a pre-planned interim analysis which identified a significant difference in PFS for patients randomized to receive Imbruvica as compared to patients receiving ofatumumab in the control arm. In addition, the IDMC also recommended that Imbruvica should be made available to all patients who were on study and in the ofatumumab arm. These data served as the basis of the supplemental New Drug Application (sNDA) to the US Food and Drug Administration (FDA) in CLL or SLL patients who have received at least one prior therapy.
CLL is a slow-growing blood cancer of white blood cells called lymphocytes, most commonly B cells. CLL is the most common adult leukaemia in the Western world and predominantly a disease of the elderly with a median age at diagnosis of 72. As this orphan disease frequently progresses after front line therapy; patients are faced with fewer treatment options and are often prescribed multiple lines of therapy as they relapse or become resistant to treatments.
Imbruvica is a first in class, oral therapy that inhibits a protein called Bruton's tyrosine kinase (BTK). BTK is a key signalling molecule of the B-cell receptor signalling complex that plays an important role in the survival and spread of malignant B cells. Imbruvica blocks signals that tell malignant B cells to multiply and spread uncontrollably.
The FDA approved Imbruvica for previously treated MCL on November 12, 2013 and for previously treated CLL on February 12, 2014. The FDA's accelerated approval for these indications was based on overall response rate of patients in the phase II clinical studies of PCYC-1104 and PCYC-1102. Imbruvica is one of the first medicines to file for FDA approval via the new Breakthrough Therapy Designation pathway, enabling Pharmacyclics to rapidly bring this medicine to patients in need.
Pharmacyclics is a biopharmaceutical company focused on developing and commercializing innovative small-molecule drugs for the treatment of cancer and immune mediated diseases.