SUNNYVALE, Calif., June 20, 2013 /PRNewswire/ -- Pharmacyclics, Inc. (the "Company") (Nasdaq: PCYC) today announced results of a study evaluating ibrutinib, an investigational oral Bruton's tyrosine kinase (BTK) inhibitor in patients with Waldenstrom's Macroglobulinemia (WM). Pharmacyclics is jointly developing ibrutinib with Janssen Research & Development, LLC. The data were presented today at the International Conference on Malignant Lymphoma (ICML), taking place in Lugano, Switzerland.
A Phase II study examining the efficacy and tolerability of ibrutinib in patients with relapsed/refractory WM was led by Dr. Steven Treon at the Bing Center for Waldenstrom's Research in Boston, MA. In WM the malignant B-cells produce large amounts of a normal antibody called immunoglobulin M (IgM). Antibodies such as IgM help the body to fight infection; however, in WM excess IgM causes the blood to thicken and causes many of the symptoms of the disease.[1],[2]
Thirty five relapsed/refractory WM patients who received a median of 2 prior therapies were evaluated. Key findings presented at ICML include:
- The best overall response rate was 83% (11.4% very good partial response; 54.3% partial response; 17.1% minor response)
- After six treatment cycles (a cycle = 4 weeks of treatment) bone marrow disease burden decreased from 70% down to 40% (p=0.0004)
- Levels of IgM reduced from 3,190 mg/dL at baseline to 1,232 mg/dL (6 cycles best response; p=5.1x10-9)
- Red blood cell production improved with levels of hematocrit increasing from 30.8% to 39.7% (6 cycles best response; p=1.1x10-11)
- The safety profile observed in patients with WM was similar to the established safety profile in other B-cell malignancies. Grade 3 and higher adverse events associated with the treatment of ibrutinib were infrequent with thrombocytopenia and neutropenia seen in 8.6%, and single cases of stomatitis and atrial fibrillation. None of these events led to ibrutinib discontinuation.
- As of June 3, 2013, 91.4% of patients remain on the study with a minimum of 6 cycles of follow up. The study was extended by an additional 28 patients to further evaluate the safety and efficacy of ibrutinib in WM and a total of 63 patients are now enrolled.
"These data suggest that ibrutinib was a highly active and well-tolerated treatment for Waldenstrom's patients in this study, and provide further evidence of the role of BTK in tumor growth," noted Steven Treon, M.D., Ph.D, Director of the Bing Center for Waldenstrom's Research and an attending physician at Dana-Farber Cancer Institute and Brigham and Women's Hospital, in Boston, MA. "Despite the relatively small patient population, there are currently no approved treatments specifically for Waldenstrom's, so the need for novel therapies such as ibrutinib should not be under-estimated."
About Ibrutinib
Ibrutinib is an investigational agent designed to specifically target and selectively inhibit an enzyme called Bruton's tyrosine kinase (BTK). BTK is a key mediator of at least three critical B-cell pro-survival mechanisms occurring in parallel – regulation of apoptosis, adhesion, and cell migration and homing. Through these multiple signals, BTK regulation helps to direct malignant B-cells to lymphoid tissues, thus allowing access to a micro environment necessary for survival.
The effectiveness of ibrutinib alone or in combination with other treatments is being studied in several B-cell malignancies, including chronic lymphocytic leukemia/small lymphocytic lymphoma, mantle cell lymphoma, diffuse large B-cell lymphoma, follicular lymphoma, Waldenstrom's macroglobulinemia and multiple myeloma. To date six Phase III trials have been initiated with ibrutinib and a total of 31 trials are currently registered on www.clinicaltrials.gov. Janssen Biotech, Inc. and Pharmacyclics entered a collaboration and license agreement in December 2011 to co-develop and co-commercialize ibrutinib.
About WM
Slow-growing and rare, with an incidence in the U.S. and Europe of approximately 3-5 cases a year per million people,[3] WM belongs to a family of cancers classified as non-Hodgkin lymphoma (NHL). WM originates from B-cells, a type of white blood cell (lymphocyte) that develops in the bone marrow. Approximately 70 percent of WM cases are diagnosed in those over the age of 65,[4] and the median overall survival is 5-11 years.[5],[6]
About Pharmacyclics
Pharmacyclics® is a clinical-stage biopharmaceutical company focused on developing and commercializing innovative small-molecule drugs for the treatment of cancer and immune mediated diseases. Our mission and goal is to build a viable biopharmaceutical company that designs, develops and commercializes novel therapies intended to improve quality of life, increase duration of life and resolve serious unmet medical healthcare needs; and to identify promising product candidates based on scientific development and administrational expertise, develop our products in a rapid, cost-efficient manner and pursue commercialization and/or development partners when and where appropriate.
Presently, Pharmacyclics has three product candidates in clinical development and several preclinical molecules in lead optimization. The Company is committed to high standards of ethics, scientific rigor, and operational efficiency as it moves each of these programs to viable commercialization.
The Company is headquartered in Sunnyvale, California and is listed on NASDAQ under the symbol PCYC. To learn more about how Pharmacyclics advances science to improve human healthcare visit us at http://www.pharmacyclics.com.
NOTE: This announcement may contain forward-looking statements made in reliance upon the safe harbor provisions of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, including statements, among others, relating to our future capital requirements, including our expected liquidity position and timing of the receipt of certain milestone payments, and the sufficiency of our current assets to meet these requirements, our future results of operations, our expectations for and timing of ongoing or future clinical trials and regulatory approvals for any of our product candidates, and our plans, objectives, expectations and intentions. Because these statements apply to future events, they are subject to risks and uncertainties. When used in this announcement, the words "anticipate", "believe", "estimate", "expect", "expectation", "goal", "should", "would", "project", "plan", "predict", "intend", "target" and similar expressions are intended to identify such forward-looking statements. These forward-looking statements are based on information currently available to us and are subject to a number of risks, uncertainties and other factors that could cause our actual results, performance, expected liquidity or achievements to differ materially from those projected in, or implied by, these forward-looking statements. Factors that may cause such a difference include, without limitation, our need for substantial additional financing and the availability and terms of any such financing, the safety and/or efficacy results of clinical trials of our product candidates, our failure to obtain regulatory approvals or comply with ongoing governmental regulation, our ability to commercialize, manufacture and achieve market acceptance of any of our product candidates, for which we rely heavily on collaboration with third parties, and our ability to protect and enforce our intellectual property rights and to operate without infringing upon the proprietary rights of third parties. Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee future results, performance or achievements and no assurance can be given that the actual results will be consistent with these forward-looking statements. For more information about the risks and uncertainties that may affect our results, please see the Risk Factors section of our filings with the Securities and Exchange Commission, including our transition report on Form 10-K for the six month period ended December 31, 2012 and quarterly reports on Form 10-Q. We do not intend to update any of the forward-looking statements after the date of this announcement to conform these statements to actual results, to changes in management's expectations or otherwise, except as may be required by law.
References
[1] Pub Med Health. Waldenstrom's macroglobulinemia; macroglobulinemia - primary; Lymphoplasmacytic lymphoma. Available from: http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001614/. Accessed May 14, 2013.
[2] American Cancer Society. Waldenstrom macroglobulinema. Available from: http://www.cancer.org/acs/groups/cid/documents/webcontent/003148-pdf.pdf. Accessed May 14, 2013.
[3] Garcia-Sanz R, Ocio E. Novel treatment regimens for Waldenstrom's macroglobulinemia. Expert Rev Hematol. 2010; 3:339-50.
[4] American Cancer Society. Waldenstrom macroglobulinemia: Key Statistics. Available from: http://www.cancer.org/cancer/waldenstrommacroglobulinemia/detailedguide/waldenstrom-macroglobulinemia-key-statistics-w-m. Accessed May 14, 2013.
[5] Vijay A, Gertz MA. Waldenstrom macroglobulinemia. Blood. 2007;109(12):5096-5103.
[6] Fonseca R, Hayman S. Waldenstrom macroglobulinaemia. Br J Haematol.2007;138(6):700-720.
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