SUNNYVALE, Calif., July 10, 2013 /PRNewswire/ -- Pharmacyclics, Inc. (Nasdaq: PCYC) today announced that it has submitted a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for the investigational oral Bruton's tyrosine kinase (BTK) inhibitor, ibrutinib, for two relapsed/refractory B-cell malignancy indications: mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). The submission was based on data from Phase II studies in patients with relapsed/refractory MCL and in patients with relapsed/refractory CLL/SLL. With this submission, Pharmacyclics is also requesting Priority Review. Pharmacyclics is jointly developing ibrutinib with Janssen. The NDA submission follows the receipt of a Breakthrough Therapy Designation from the FDA in February 2013 for ibrutinib as a monotherapy for the treatment of patients with relapsed/refractory MCL, and receipt of a second Breakthrough Therapy Designation for the treatment of patients with CLL/SLL with deletion of the short arm of chromosome 17 (del 17p). Further information on the implications of this filing for potential commercialization will be provided subsequent to the FDA rendering a decision on the filing. "We are very excited having achieved this major milestone. This first NDA for ibrutinib was made possible in record time because of the continuous support and consultations we received from the FDA," said Dr. Urte Gayko, Senior Vice President of Global Regulatory Affairs, Pharmacyclics. "We look forward to continuing to work with the FDA as they review the application for ibrutinib through the new Breakthrough Therapy Designation process." "These past months have been enormously active and productive for Pharmacyclics and our ibrutinib partner, Janssen. We received our first of three Breakthrough Therapy Designations just this past February and since then published various clinical results in patients with CLL del17p and also in patients with Waldenstroms; in April we completed enrollment of our first Phase III study; last month, results of two of our trials were published in the prestigious New England Journal of Medicine and today Pharmacyclics announced the filing of its first NDA for ibrutinib with the Food and Drug Administration," said Bob Duggan CEO and Chairman of Pharmacyclics. "Thus far, more than 1600 patients have been treated in our studies with ibrutinib and we are making excellent progress in the development and preparation for commercialization of this investigational drug. As of today, we have initiated 7 Phase III studies together with our partner Janssen and have currently registered with the US National Institute of Health 31 clinical trials using ibrutinib. It is Pharmacyclics's goal to advance science and drug development in the hopes of making a significant difference for the betterment of patients with serious unmet healthcare needs, and with the announcement today we have accomplished an important milestone in our timeless journey." About CLL / SLLCLL, a B-cell malignancy, is a slow-growing blood cancer that starts in the white blood cells (lymphocytes), most commonly from B-cells. CLL is the second most common adult leukemia. Approximately 15,680 patients in the US are diagnosed each year with CLL. The prevalence of CLL is approximately 113,000 in the U.S. It is a chronic disease of the elderly with a five-year survival of approximately 82 percent. 1 Patients commonly receive multiple lines of treatment over the course of their disease. When cancer cells are located mostly in the lymph nodes, the disease is called SLL. CLL and SLL are considered to be different manifestations of the same underlying disease; they share similarities in signs and symptoms, genetic features, disease progression and treatment. In CLL, the genetic mutation del 17p occurs when the short arm of chromosome 17 is missing. Del 17p CLL is associated with abnormalities of a key tumor suppressor gene, TP53, which results in poor response to chemoimmunotherapy and worse treatment outcomes. It occurs in about seven percent of treatment naïve CLL patients, with approximately 20-40 percent of relapsed/refractory patients harboring the mutation.