Immunomedics Announces Results From Two Clinical Trials at Hematology Conference

Immunomedics Announces Results From Two Clinical Trials at Hematology Conference

SAN DIEGO, Dec. 13, 2011 (GLOBE NEWSWIRE) -- Immunomedics, Inc. (Nasdaq:IMMU), a biopharmaceutical company primarily focused on the development of monoclonal antibody-based products for the targeted treatment of cancer, autoimmune and other serious diseases, today announced that two studies conducted by outside investigators that involved the Company's antibody drug candidates were presented at the 53rd Annual Meeting of the American Society of Hematology.

Led by Dr. Lapo Alinari of the Comprehensive Cancer Center, The Ohio State University, Columbus, OH, the first study is a Phase I/II trial evaluating the safety, tolerability, and overall response rate of combining milatuzumab, the first humanized anti-CD74 antibody in clinical testing, and veltuzumab, a second-generation humanized anti-CD20 antibody, in patients with relapsed or refractory B-cell non-Hodgkin lymphoma (NHL) after at least 1 prior therapy. The milatuzumab+veltuzumab combination has previously demonstrated in vitro anti-tumor activity in preclinical studies performed at the Ohio State University.

Patients in this Phase I/II study received veltuzumab at 200 mg/m2 weekly combined with escalating doses of milatuzumab at 8, 16, and 20 mg/kg twice per week of weeks 1 to 4, 12, 20, 28, and 36. Three of the first 6 patients enrolled at dose levels 1 and 2 had significant grade 3 infusion reactions with milatuzumab. The study was amended to separate veltuzumab and milatuzumab dosing days and to add additional premedication. No dose-limiting toxicities were then observed, and no patients experienced grade 3 infusion reactions after the protocol was modified. Human anti-veltuzumab and anti-milatuzumab antibodies, collected on day 1 of weeks 4, 12, and 36, have not been detected in any patient.

The dose-escalation phase of this study has completed enrollment with 18 patients diagnosed with various types of NHL, including both indolent and aggressive forms, having received at least 4 weeks of the combination therapy. All 18 patients were assessable for response at week 5.

Overall, 14 patients had evidence of antitumor activity, with 4 patients (22%) having an objective response, including 2 complete responses. Of the 2 patients who achieved a complete response, 1 patient with grade 1-2 follicular NHL who was rituximab-refractory and had undergone an allogeneic transplant and 1 patient with marginal zone lymphoma who remains in remission at 13 months. Partial responses were seen in 2 patients with grade 3 follicular NHL refractory to rituximab. Stable disease (SD) was observed in 10 patients of a median duration of 5.25 months (range 2.5-12 months) and 2 remain on protocol therapy. All responding patients achieved response following induction therapy. Responses were not dose-dependent and occurred at dose levels 1 and 2.

These results demonstrated that combination therapy with veltuzumab and milatuzumab was active and well-tolerated in a population of heavily pre-treated patients with relapsed or refractory NHL. The study has been expanded into a Phase II trial to further evaluate the efficacy of the combination in selected subtypes of NHL.

The second investigator-sponsored study reported at the same conference was a Phase II trial conducted by The Children's Oncology Group to determine if addition of epratuzumab to an established chemotherapy platform could improve rates of successful induction of second remission (CR2) in children with B-cell precursor (BCP) acute lymphoblastic leukemia (ALL) and early bone marrow relapse. Previously, the feasibility portion of the study had produced a complete remission rate of 75% in 15 patients, of whom 7 showed no residual disease.

A total of 116 patients, ages 2-30 years with first, early marrow relapse of BCP ALL, with or without extramedullary disease, were enrolled in this multicenter study. The primary study endpoint was CR2 rate at the end of the first block of chemotherapy plus epratuzumab as compared to the 67% CR2 rate for historical controls. For addition of epratuzumab to be deemed effective, an improvement in CR2 rate of 13% (67% vs. 80%) was required.

Epratuzumab, at 360 mg/m2 per dose, was tolerable in combination with chemotherapy in pediatric and young adult patients with early relapsed CD22-positive BCP ALL, but did not significantly improve the CR2 rates when compared to historical controls treated with chemotherapy alone. However, among patients who attained a complete remission, those treated with epratuzumab were significantly more likely to become minimal residual disease negative as compared to those treated without epratuzumab. Therefore, the study will await final survival results to assess the meaning of the effect of epratuzumab on minimal residual disease becoming negative.

"We are currently collaborating with multiple investigators in Europe to further evaluate epratuzumab in children with ALL. A multicenter, multi-national, Phase III clinical trial is expected to begin in 2012," stated Cynthia L. Sullivan, President and Chief Executive Officer of Immunomedics.

About Immunomedics

Immunomedics is a New Jersey-based biopharmaceutical company primarily 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, cytokines 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 also have a majority ownership in IBC Pharmaceuticals, Inc., which is developing a novel Dock-and-Lock (DNL) methodology with us for making fusion proteins and multifunctional antibodies, 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. We believe that our portfolio of intellectual property, which includes approximately 186 patents issued in the United States and more than 400 foreign patents, protects our product candidates and technologies. For additional information on us, please visit our website at 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, potential collaborations, 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 partners for the further development of epratuzumab for autoimmune indications and veltuzumab for non-cancer 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.

CONTACT: Dr. Chau Cheng
Director, Investor Relations & Grant Management
(973) 605-8200, extension 123
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