New Candidate Antibody-Drug Conjugate Gains Broad Patent Coverage

MORRIS PLAINS, N.J., Dec. 22, 2010 (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 additional claims for the patent family, "RS7 antibodies," were issued as Patent No. 1,002,443 in Korea. The new patent, which expires in March, 2023, covers compositions of humanized antibodies that target epithelial glycoprotein-1 (EGP-1 or TROP-2) for use in the treatment and diagnosis of cancer.  Comparable patents have also issued in the United States, Europe, Japan, Australia, China and Israel.

EGP-1, or TROP-2, has higher expression in prostate, lung, breast, ovarian, and cervical cancers as compared to normal tissues. The Company has developed the humanized monoclonal antibody, hRS7, for targeted therapy of multiple solid cancers.  hRS7 has also been shown to internalize into cancer cells, making it a suitable candidate for delivery of cytotoxic drugs. 

The Company has conjugated SN-38, the active metabolite of irinotecan used in chemotherapeutic regimens for colorectal, lung, and pancreatic cancers, to hRS7 for targeted treatment of cancer. Preclinical studies have indicated potent therapeutic effects of the antibody-drug conjugate in a human lung cancer model. (Please refer to the Company's press release at http://www.immunomedics.com/news_pdf/2008_PDF/PR03202008.pdf for more information). The development of hRS7-SN-38 conjugate has been supported in part by a grant from the Small Business Innovation Research Program of the National Cancer Institute, National Institutes of Health.

Additionally, by conjugating the RNA-degrading enzyme, RNase, to hRS7, the Company has demonstrated selective killing of cancers expressing the EGP-1 biomarker, including prostate and lung cancers.  (For more information, please refer to the Company's press release at http://www.immunomedics.com/news_pdf/2007_PDF/PR04172007.pdf ).  

Commenting on the new patent award, Cynthia L. Sullivan, President and Chief Executive Officer, said, "TROP-2 is a novel cancer target that we believe so far is only pursued by us. We are pleased to have received this new, 7 ^th patent, and look forward to developing this important new antibody for the therapy of multiple solid cancers."   "Results in preclinical models with various human cancers are being prepared for publication in a cancer journal," she added.

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 154 patents issued in the United States and more than 375 other patents issued worldwide, protects our product candidates and technologies. 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, 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: Immunomedics, Inc.
         Dr. Chau Cheng, Director, Investor Relations
          & Grant Management
         [phone], extension 123
         [e-mail]