Immunomedics (IMMU) Presents Clinical Progress of Antibody-Drug Conjugate Programs

MORRIS PLAINS, N.J., May 30, 2013 (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, announced that during the Company’s presentation at the New York Biotechnology Association’s Annual Meeting yesterday, President and CEO, Cynthia L. Sullivan, updated the audience on the progress of the antibody-drug conjugate (ADC) programs.

“Although we have three ADC’s in clinical development, recent results with the two being studied in patients with advanced solid tumors, particularly metastatic colorectal and triple-negative breast cancers, are particularly encouraging,” Ms. Sullivan remarked. She added that “tumor shrinkage, including partial responses determined by RECIST criteria, was achieved in dose-escalation trials of IMMU-130 and IMMU-132 ADC product candidates.”

Both ADC product candidates involve SN-38, the active metabolite of irinotecan (used to treat metastatic colorectal and other solid cancers), conjugated by the Company’s proprietary technology to labetuzumab (anti-CEACAM5 humanized monoclonal antibody; IMMU-130) or the anti-TROP-2 humanized antibody, hRS7 (IMMU-132). Whereas IMMU-130 is being studied in advanced colorectal cancer patients who have failed irinotecan therapy, IMMU-132 is being tested in 13 cancer types, including colorectal, triple-negative breast, bladder, pancreas, prostate, kidney, and ovarian cancers.

“Since we have seen tumor shrinkage, including partial responses, so early in these trials, and that SN-38 bound to two different antibodies has been active, our confidence is increased regarding the future potential of these ADC candidates for treating these major cancer types after they become refractive to conventional chemotherapeutic agents,” Ms. Sullivan stated. “The major toxicities, to date, have been diarrhea and neutropenia, which generally can be alleviated by other medications, and these appear to be less frequent and milder than with irinotecan therapy,” she remarked further.

Ms. Sullivan also stated that the Phase Ib trial of ⁹⁰Y-clivatuzumab tetraxetan in patients with advanced, third-line, pancreatic cancer is reaching completion of follow-up and survival results continue to be analyzed. This trial compared clivatuzumab alone to the combination of clivatuzumab with low-dose gemcitabine in an open-label, randomized trial.

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™) method 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 223 active patents in the United States and more than 400 foreign patents, protects our product candidates and technologies. Our strength in intellectual property has resulted in the top-10 ranking in the 2012 IEEE Spectrum Patent Power Scorecards in the Biotechnology and Pharmaceuticals category. For additional information on us, please visit our website at 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, 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 any cash payment that the Company might receive in connection with a sublicense involving a third party and UCB, which is not within the Company’s control, new product development (including clinical trials outcome and regulatory requirements/actions), our dependence on our licensing partners for the further development of epratuzumab 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
         Senior Director, Investor Relations & Grant Management
         (973) 605-8200, extension 123
         ccheng@immunomedics.com