ATLANTA, Dec. 10, 2007 (PRIME NEWSWIRE) -- Immunomedics, Inc. (Nasdaq:IMMU), a biopharmaceutical company focused on developing monoclonal antibodies to treat cancer and other serious diseases, announced today that its lead product candidate, epratuzumab, produced durable complete responses in patients with recurrent or refractory non-Hodgkin's lymphoma (NHL) when used in combination with rituximab. John P Leonard, MD, Weill Cornell Medical College, presented the final clinical trial results at the 49th annual meeting of ASH in Atlanta, GA.
Forty-nine patients with recurrent or refractory low-grade CD20-positive B-cell NHL were enrolled in this multicenter, open-label, single-arm study. Fourteen patients had prior rituximab therapy with the remaining thirty-five being rituximab-naive. All patients received infusions of 360 mg/m2 of epratuzumab followed by 375 mg/m2 rituximab weekly for four consecutive weeks. One patient discontinued rituximab after an infusion reaction, but completed epratuzumab treatment.
Twenty-six patients, or 54%, achieved an objective response (OR), including 27% with complete responses (CR/CRu) and 27% with partial responses (PR). The combination immunotherapy was active not only in 41 low-grade follicular patients (54% OR, 24% CR) but also 7 patients with small lymphocytic lymphoma (57% OR, 43% CR/CRu). Moreover, comparable activity was seen in both 34 rituximab-naive patients (50% OR, 26% CR/CRu) and 14 patients who had responded to prior rituximab (64% OR, 29% CR).
Overall, the median duration of objective response (DR) was 14.7 months and the median progression-free survival (PFS) was 11.1 months. Follicular patients had durable responses with a median PFS of 10.0 months and median DR of 13.4 months. Follicular patients with CRs had especially long-lived responses, with a median PFS of 35.1 months and median DR of 33.4 months, including long-term responses still continuing for over 4 years.
"These final results confirm that adding epratuzumab to rituximab did not produce additive toxicity over that expected with rituximab alone, and the combination therapy was well tolerated by patients. This study demonstrates promising anti-lymphoma activity for indolent NHL, and can result in durable complete remissions in a significant subset of patients," remarked Dr. Leonard, lead investigator of the study.
"These encouraging results have generated interests from various study groups of the National Cancer Institute," commented Cynthia L. Sullivan, President and Chief Executive Officer. "It appears that NHL patients may benefit from combination therapy involving CD22 and CD20 monoclonal antibodies with different mechanisms of action," she commented further.
Epratuzumab is currently being studied in a Phase II trial by the Children's Oncology Group of the National Cancer Institute (NCI) in children with acute lymphoblastic leukemia. The North Central Cancer Treatment Group, a national clinical research group sponsored by the NCI, has completed patient enrollment with their Phase II trial evaluating epratuzumab in combination with rituximab and CHOP chemotherapy in patients with previously untreated diffuse large B cell lymphoma. Additionally, the Cancer and Leukemia Group B of NCI is planning a Phase II trial using epratuzumab and rituximab as initial therapy for indolent NHL patients.
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 exclusively licensed our lead product candidate, epratuzumab, to UCB (www.ucb-group.com) for the treatment of all autoimmune disease indications worldwide. Epratuzumab's most advanced program is for the treatment of systemic lupus erythematosus (SLE). 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. We have retained the rights for epratuzumab in oncology indications for which UCB has been granted a buy-in option. The Company is conducting clinical trials with veltuzumab in patients with non-Hodgkin's lymphoma, epratuzumab as a potential therapeutic for patients with lymphoma and leukemia, 90Y-epratuzumab for the therapy of patients with lymphoma, 90Y-hPAM4 for pancreas cancer therapy and milatuzumab 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.