VANCOUVER, British Columbia, June 11, 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 reported that epratuzumab labeled with the radioisotope, yttrium-90 (90Y), given in small doses in combination with veltuzumab is therapeutically active in patients with aggressive non-Hodgkin lymphoma (NHL). Results from this multicenter study were presented by Michael B. Tomblyn, MD, of H. Lee Moffitt Cancer Center in Tampa, FL.
Despite the advent of immunotherapy with anti-CD20 antibody for B-cell malignancies, aggressive NHLs remain a challenge, requiring the addition of chemotherapy. An attractive prospect for NHL therapy is to combine immunotherapy with radioimmunotherapy (RIT) targeting a different B-cell antigen. Since CD20 and CD22 are distinct antigens, anti-CD20 antibodies should not cross-block anti-CD22 RIT in such a treatment regimen.
In a previous clinical study, anti-CD22 RIT with 90Y-epratuzumab has produced results that are comparable to other interventions.1 Moreover, given that the anti-CD20 veltuzumab also compared well to published results with rituximab,2,3 the Company is conducting a Phase I/II study to evaluate the potential of 90Y-epratuzumab combined with veltuzumab in patients with aggressive NHL.
Results from 18 patients with various types of aggressive NHL who had failed 1 or more prior standard therapies were reported at the medical conference. Based upon prior study of 90Y-epratuzumab given alone in mostly indolent NHL patients, 2 infusions at 15 mCi/m2 were the initial dosage. However, 90Y-doses were lowered due to dose-limiting thombocytopenia and neutropenia, although most counts recovered within 1 – 8 weeks with no cases of transfusion-dependent thrombocytopenia. Maximum tolerated dose was determined as 2 infusions at 6 mCi/m2. One patient withdrew before evaluation due to a severe adverse event.
The overall objective response rate among 17 patients who have had treatment response assessments was 53% (9/17), with 2 patients (17%) reporting a complete response (CR). One of the CR patients improved from a partial response (PR) after being retreated with 90Y-epratuzumab. The other complete responder is continuing at 18 months. The combination is active in all NHL subgroups and across all 90Y-dose levels tested and IPI scores. At the maximum tolerated dose of 6 mCi/m2 x 2, 5 of 6 patients (83%) reported a PR or better.
"We are very encouraged by these early efficacy results, especially in light of the current low dose of 90Y," remarked Cynthia L. Sullivan, President and Chief Executive Officer of Immunomedics. "The Phase II part of this study is now underway," Ms. Sullivan added.
This study was supported in part by Award Number R44CA139668 from the National Cancer Institute. The content is solely the responsibility of the Company and does not necessarily represent the official views of the National Cancer Institute or the National Institutes of Health.
| Treatment responses | |||||
|
Subgroups |
Number of Patients |
Objective Response (%) |
Complete Response (N) |
Partial Response (N) |
Stable Disease (N) |
| Histology | |||||
| Diffuse large B-cell lymphoma | 8 | 50% | 2 | 2 | 1 |
| Mantle cell lymphoma | 5 | 20% | 0 | 1 | 3 |
| Transformed follicular lymphoma | 4 | 100% | 0 | 4 | 0 |
| 90Y Dose Level | |||||
| 12 + 15 mCi/m2 | 5 | 60% | 1 | 2 | 1 |
| 9 mCi/m2 | 6 | 17% | 0 | 1 | 3 |
| 6 mCi/m2 | 6 | 83% | 1 | 4 | 0 |
| International Prognostic Index Scores | |||||
| High-Int/High (3-4) | 8 | 25% | 1 | 1 | 3 |
| Low/Low-Int (0-2) | 9 | 78% | 1 | 6 | 1 |
Reference
- Morschhauser F., Kraeber-Bodéré F., Wegener W.A., Harousseau J.L., Petillon M.O., Huglo D., Trümper L.H., Meller J., Pfreundschuh M., Kirsch C.M., Naumann R., Kropp J., Horne H., Teoh N., Le Gouill S., Bodet-Milin C., Chatal J.F., Goldenberg D.M. High rates of durable responses with anti-CD22 fractionated radioimmunotherapy: results of a multicenter, phase I/II study in non-Hodgkin's lymphoma. J Clin Oncol. 2010 Aug 10;28(23):3709-16. doi: 10.1200/JCO.2009.27.7863. Epub 2010 Jul 12.
- Morschhauser F,. Leonard J.P., Fayad L., Coiffier B., Petillon M.O., Coleman M., Schuster S.J., Dyer M.J., Horne H., Teoh N., Wegener W.A., Goldenberg D.M. Humanized anti-CD20 antibody, veltuzumab, in refractory/recurrent non-Hodgkin's lymphoma: phase I/II results. J Clin Oncol. 2009 Jul 10;27(20):3346-53. doi: 10.1200/JCO.2008.19.9117. Epub 2009 May 18.
- Negrea G.O., Elstrom R., Allen S.L., Rai K.R., Abbasi R.M., Farber C.M., Teoh N., Horne H., Wegener W.A., Goldenberg D.M. Subcutaneous injections of low-dose veltuzumab (humanized anti-CD20 antibody) are safe and active in patients with indolent non-Hodgkin's lymphoma. Haematologica. 2011 Apr;96(4):567-73. doi: 10.3324/haematol.2010.037390. Epub 2010 Dec 20.
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.