VIENNA, Austria, June 11 /PRNewswire-FirstCall/ -- Immunomedics, Inc. , a biopharmaceutical company focused on developing monoclonal antibodies to treat cancer and other serious diseases, today announced that data presented at the 12th Congress of EHA in Vienna, Austria, showed positive responses in patients with non-Hodgkin’s lymphoma (NHL) treated with a new radioimmunotherapy (RAIT) using epratuzumab to deliver toxic radiation directly to lymphoma cells in small fractions. Franck Morschhauser, MD, Centre Hospitalier Regional Universitaire de Lille, Lille, France, is the lead investigator of this open-label, multicenter Phase I/II dose-escalation study and the presenter at the meeting.
Current RAIT treatments for NHL such as tositumomab and ibritumomab tiuxetan are radiolabeled murine antibodies targeting the CD20 antigen on the surface of mature B-cells and B-cell tumors as expressed by NHL cells. Immunomedics’ epratuzumab is a humanized monoclonal antibody that targets the CD22 antigen on B-cells, including malignant B-cells. The internalizing property of epratuzumab is believed to be well suited for delivering radiation from the potent radioisotope, yttrium-90, selectively and locally to lymphoma cells that express the CD22 antigen. Moreover, because epratuzumab is humanized, it is argued that the new RAIT can be administered to patients repeatedly in smaller doses. Researchers found that splitting the dose over two or three fractions made it tolerable to patients while delivering higher radioactivity to tumor cells.
At the time of reporting, 54 patients were evaluated with an overall objective response rate of 59% and a complete response rate of 43%. Moreover, responses appear durable with 6 complete responders who remained disease free for more than 1 year, including 4 continuing for more than 2 years. Both the objective and complete response rates appear to increase with higher cumulative doses. Objective responses occurred for 41% of patients at the lowest total doses of 5-10 mCi/m(2), compared to 55% in the groups receiving 15-20 mCi/m(2), 63% in the 22.5-37.5 mCi/m(2) cohorts, and 90% receiving the highest cumulative doses of 37.5-45 mCi/m(2). Similarly, complete responses occurred for 29% of patients in the 5-10 mCi/m(2) total dose groups, compared to 45% at 15-20 mCi/m(2), 44% at 22.5-37.5 mCi/m(2), and 60% at 37.5-45 mCi/m(2).
Importantly, 64% of patients who had received prior rituximab-containing regimens responded to (90)Y-epratuzumab, as well as 41% of patients with prior bone marrow transplant. Moreover, responses were seen in patients with different types of NHL. Sixty-eight percent of patients with follicular lymphoma responded to the RAIT, compared to 57% for mantle cell lymphoma, 22% for diffuse large B-cell lymphoma, and all 3 patients with marginal zone lymphoma.
“We are very encouraged by these results. Not only did we observe high response rates but, more importantly, the responses were seen in patients with different types of NHL, and in rituximab-treated or naïve patients with or without a history of bone marrow transplants,” remarked Dr. Franck Morschhauser.
Adult patients with documented B-cell NHL who failed at least one prior regimen of standard chemotherapy were eligible for this study. At the time of reporting, 58 patients with a median of 3 prior therapies have completed treatment. Patients were treated once weekly for two or three consecutive weeks and the (90)Y dose was escalated in successive patient cohorts. For patients with prior bone marrow transplants, dose escalation stopped at 10 mCi/m(2) total dose (5.0 mCi/m(2) x 2 weeks). For patients without prior bone marrow transplants, however, the study is continuing at the highest tested level of 45 mCi/m(2) total dose (15.0 mCi/m(2) x 3 weeks).
“We are particularly enthused by the strong safety profile, which we believe allows us to increase the radiation dosage needed to achieve more effective results. The 45 mCi/m(2) cumulative dose level is more than two-fold higher than the maximum allowable dose of 32 mCi for ibritumomab tiuxetan, or 18.5 mCi/m(2) based on a body area of 1.73 m(2) for a standard person,” commented Cynthia L. Sullivan, President and Chief Executive Officer. “This study is now almost completed, and we will decide to either out-license this agent, or complete the clinical development on our own,” she added.
About Immunomedics
Immunomedics is a New Jersey-based biopharmaceutical company focused on the development of monoclonal, antibody-based products for the targeted treatment of cancer, autoimmune and other serious diseases. We have developed a number of advanced proprietary technologies that allow us to create humanized antibodies that can be used either alone in unlabeled or “naked” form, or conjugated with radioactive isotopes, chemotherapeutics or toxins, in each case to create highly targeted agents. Using these technologies, we have built a pipeline of therapeutic product candidates that utilize several different mechanisms of action. We have licensed our lead product candidate, epratuzumab, to UCB, S.A. for the treatment of all autoimmune disease indications worldwide. We have retained the rights for epratuzumab in oncology indications for which UCB has been granted a buy-in option. UCB has development, manufacture and commercialization rights, and is responsible for all clinical trials evaluating epratuzumab for the treatment of patients with moderate and severe lupus. At present, there is no cure for lupus and no new lupus drug has been approved in the U.S. in the last 40 years. The Company is conducting clinical trials with hA20 in patients with non-Hodgkin’s lymphoma, epratuzumab as a potential therapeutic for patients with lymphoma and leukemia, (90)Y-epratuzumab for the therapy of patients with lymphoma, (90)Y- hPAM4 for pancreas cancer therapy and hCD74 as a therapy for patients with multiple myeloma. We believe that our portfolio of intellectual property, which includes approximately 108 patents issued in the United States, and more than 250 other issued patents worldwide, protects our product candidates and technologies. We also have a majority ownership in IBC Pharmaceuticals, Inc., which is developing a novel Dock and Lock (DNL) methodology, and a new method of delivering imaging and therapeutic agents selectively to disease, especially different solid cancers (colorectal, lung, pancreas, etc.), by proprietary, antibody-based, pretargeting methods. For additional information on us, please visit our web site at http://www.immunomedics.com. The information on our website does not, however, form a part of this press release.
This release, in addition to historical information, may contain forward- looking statements made pursuant to the Private Securities Litigation Reform Act of 1995. Such statements, including statements regarding clinical trials, out-licensing arrangements (including the timing and amount of contingent payments), forecasts of future operating results, and capital raising activities, involve significant risks and uncertainties and actual results could differ materially from those expressed or implied herein. Factors that could cause such differences include, but are not limited to, risks associated with new product development (including clinical trials outcome and regulatory requirements/actions), our dependence on our licensing partner for the further development of epratuzumab for autoimmune indications, competitive risks to marketed products and availability of required financing and other sources of funds on acceptable terms, if at all, as well as the risks discussed in the Company’s filings with the Securities and Exchange Commission. The Company is not under any obligation, and the Company expressly disclaims any obligation, to update or alter any forward-looking statements, whether as a result of new information, future events or otherwise.
For More Information: Dr. Chau Cheng Associate Director, Investor Relations & Business Analysis (973) 605-8200, extension 123 ccheng@immunomedics.com
Immunomedics, Inc.
CONTACT: Dr. Chau Cheng, Associate Director, Investor Relations & BusinessAnalysis, of Immunomedics, Inc., +1-973-605-8200, extension 123,ccheng@immunomedics.com
Web site: http://www.immunomedics.com//
Company News On-Call: http://www.prnewswire.com/comp/113121.html/
