-- Preclinical Study Presented at 2013 Annual Meeting of the American Association for Cancer Research (AACR) --
-- Study on Mechanism of Cancer Metastasis also Reported --
WASHINGTON, April 8, 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, today announced the creation of a new class of antibody-cytokine conjugates using the Company's patented DOCK-AND-LOCK™ (DNL™) platform technology. These DNL™ complexes demonstrated potent anti-tumor activity in preclinical studies.The Company has previously reported the development of antibody-directed interferon-alpha 2b (IFN alpha 2b) complexes. (For more information, please refer to the Company's press release at www.immunomedics.com/pdfs/news/2009/PR04222009A.pdf ). Veltuzumab-IFN alpha 2b is the most advanced product from this group of IFN alpha-based DNL™ complexes, and is currently being developed for improved therapy of B-cell malignancies, partially supported by a grant from the Small Business Innovation Research program of the National Cancer Institute totaling $2.8 million. While functioning similarly to IFN-alpha in eliciting anti-viral, anti-tumor, and immune-modulating activities, IFN-lambda is being considered as a potential alternative to existing IFN-alpha therapeutic regimens due to its more restricted cellular targets. Antibody-targeted IFN- lambda may further improve its safety, potency and pharmacokinetics. In the current study, 3 DNL TM complexes of IFN- lambda, designated (E1)- lambda 1, (15)- lambda 1, and (C2)- lambda 1, were generated by site-specifically conjugating IFN- lambda 1 to 3 of the Company's proprietary humanized antibodies, hRS7 (anti-TROP-2), hMN-15 (anti-CEACAM6), and hL243 (anti-HLA-DR), respectively. These antibody-cytokine conjugates were evaluated in human malignant cell lines of cervix, colon, esophagus, lung, liver, and skin. Targeting of these antibody-cytokine conjugates to antigen-expressing cells markedly increased the amount of IFN- lambda 1 localized at the cell surface. As a result, (E1)- lambda 1 inhibited the in vitro proliferation of the cervical, lung and esophageal cancer cell lines at less than 1 picomolar (pM) concentration, which was 1,000-fold more potent than commercial IFN- lambda 1. Likewise, the anti-proliferation activity of (15)- lambda 1 was enhanced ~100-fold in cervical and esophageal cancer cells, but not in CEACAM6-negative lung cancer cells. "These promising results, attributable to increased localization and stronger binding to antibody-targeted cells, warrant further exploration as potential cancer therapeutics," remarked Cynthia L. Sullivan, President and Chief Executive Officer.