NEW ORLEANS and SUNNYVALE, Calif., Dec. 7 /PRNewswire-FirstCall/ -- Pharmacyclics, Inc. today announced interim data from a Phase I study of their novel orally administered Bruton's tyrosine kinase (Btk) inhibitor PCI-32765 in patients with relapsed or refractory B-cell non-Hodgkin's lymphoma (NHL) or chronic lymphocytic leukemia (CLL). These data are being presented at the American Society of Hematology (ASH) 51st Annual Meeting taking place this week in New Orleans, LA.
In the first 2 dose cohorts, 16 heavily pretreated and progressing lymphoma patients with a variety of B-cell malignancies were evaluated. In the first dose cohort, 7 patients were treated with PCI-32765 resulting in 2 partial responses (e.g. a 50% decrease in sum of the product of the diameters of up to 6 largest dominant masses; no increase in size of other nodes per the Revised Response Criteria for Malignant Lymphoma Bruce D. Cheson J Clin Oncol 25:579-586,) one in mantle cell lymphoma, one in follicular lymphoma and one patient with stable disease for approximately 5 cycles. In the second dose cohort, 9 patients were treated resulting in 3 partial responses (one patient with mantle cell lymphoma and two patients with chronic lymphocytic leukemia (CLL/SLL)) and 2 patients with stable disease for approximately 2 cycles. The overall response rate (ORR), considering only partial and complete responses, was 31% for the first two dose cohorts.
The trial is currently enrolling at a rapid rate. We anticipate the fourth dose cohort to commence in December 2009. At this time the company anticipates dosing only the first 5 dose cohorts to complete this Phase I study, as per the protocol dosing will continue to three levels above full kinase occupancy.
"PCI-32765 appears to be well tolerated by patients at oral doses that are able to fully inhibit the enzyme Btk," said Dr. Ranjana Advani, Associate Professor, Stanford University Medical Center and principal investigator of the trial. "In addition, we now have evidence of drug activity."
Bruton's Tyrosine Kinase and Immune Diseases
B-cells are immune cells, which are activated by antigens, pathogens or, in the case of autoimmunity, by host tissues. B-cells produce antibodies, which when self-reactive can trigger autoimmune disease. Activation of B-cells is also thought to play a major role in lymphomas where continuous, or tonic, stimulation results in uncontrolled B-cell proliferation. Btk is a type of enzyme known as a tyrosine kinase inside B-cells that plays an early key role in B-cell activation. Drugs that can inhibit Btk may prevent B-cell activation and therefore may play a role in the treatment of lymphomas or autoimmune disease. Other tyrosine kinases are important in cell signaling and have been targets for other drugs such as Gleevec(R) (imatanib mesylate), which is approved for treatment of certain leukemias. New drug or biological candidates targeting B-cells, including Rituxan for lymphomas and rheumatoid arthritis, are aimed at eliminating abnormally functioning B-cells.
According to the National Cancer Institute's SEER database the incidence of NHL (all types including Follicular and Aggressive) is projected at nearly 66,000 in 2009 and that 19,500 patients are expected to die from this disease in the United States in 2009. According to the Leukemia & Lymphoma Society (LLS), there are approximately 452,723 people in the U.S. living with NHL (with active disease or in remission).
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 regarding our expectations and beliefs regarding our future results or performance. 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", "should", "would", "project", "plan", "predict", "intend" and similar expressions are intended to identify such forward-looking statements. Our actual results could differ materially from those projected in the forward-looking statements. Additionally, you should not consider past results to be an indication of our future performance. For a discussion of the risk factors and other factors that may affect our results, please see the Risk Factors section of our filings with the Securities and Exchange Commission, including our annual report on Form 10-K 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.
CONTACT: R. Erdtmann, VP Finance of Pharmacyclics, Inc., +1-408-215-3325
Web site: http://pharmacyclics.com/
