December 9, 2009 (FinancialWire) — Immunomedics, Inc. (NASDAQ: IMMU) said subcutaneous injections of low doses of veltuzumab in patients with non-Hodgkin’s lymphoma achieved sustained serum levels of pharmacologically active antibody, with objective response rates comparable to those seen with higher intravenous doses.

The goal of this multicenter, open-label, Phase I/II study was to evaluate the safety, tolerability, and preliminary efficacy of subcutaneous veltuzumab in patients with previously untreated or relapsed CD20-positive indolent NHL or chronic lymphocytic leukemia . At the time of reporting, 17 NHL patients and 11 CLL patients had been enrolled to receive 4 subcutaneous injections of veltuzumab given 2 weeks apart at dose levels of 80, 160, or 320 mg. Efficacy was assessed at 4 and 12 weeks post treatment, with responding patients continuing follow-up.

In the 15 evaluable NHL patients, the objective response rate was 53%, with a complete response rate of 27%. For the 12 follicular lymphoma patients, objective and complete response rates were 58% and 25%, respectively. These results were comparable to the Phase I/II results using the intravenous formulation published by the Company (for more information, please refer to the company’s press release at www.immunomedics.com/news_pdf/2009_PDF/PR05182009.pdf), suggesting that the subcutaneous formulation may be active against NHL. Moreover, 7 of the 8 objective responders are currently continuing in remission, now up to 6 months after treatment.

In the 9 CLL patients with response assessments available, high levels of circulating leukemic cells substantially reduced the serum veltuzumab levels. As a result, more frequent and prolonged dosing is likely required. Overall, there were no objective responses, but 5 patients showed stable disease for up to 12 weeks.

Immunomedics is collaborating with Nycomed, which received the exclusive, worldwide rights to develop, manufacture and commercialize the subcutaneous formulation of veltuzumab for the treatment of all non-cancer indications.

At the same conference, the company also reported preclinical results of a new antibody, IMMU-114, for the therapy of B-cell malignancies. IMMU-114 is a humanized antibody targeting the HLA-DR antigen. The goals of the preclinical studies were to investigate the cytotoxic effects of IMMU-114 on leukemia, lymphoma, and multiple myeloma cell lines, as well as clinical specimens of CLL, and explore the signaling pathways involved.

Four of 6 CLL patient samples expressed HLA-DR at markedly higher levels than CD20, with the remaining 2 showing similar HLA-DR and CD20 expression. High expression of HLA-DR was also detected on the cell surface of all mantle cell lymphoma, acute lymphoblastic leukemia, hairy cell leukemia, CLL, and NHL cell lines tested, as well as 2/3 acute myeloid leukemia and 5/6 MM cell lines.

Approximately 60% cytotoxicity was obtained in CLL patient cells after incubation with IMMU-114. The humanized anti-HLA-DR antibody was cytotoxic to 2/2 MCL, 2/2 CLL, 2/4 ALL, 1/1 HC, 2/2 NHL and 2/2 MM cell lines without any added crosslinking antibody. Importantly, IMMU-114 was consistently more cytotoxic than anti-CD20 antibodies on these cell lines, as well as on 2 rituximab-resistant NHL variant cell lines.

The therapeutic activity of IMMU-114 was evaluated in 3 NHL mouse models. In one model, IMMU-114 treatment yielded 100% long-term survival. Although rituximab also induced significant responses compared to untreated mice (median survival time of 87.5 vs. 36 days for untreated controls), no long-term survivors were seen. IMMU-114 was also more effective than rituximab in the other two models. Encouraged by these findings, the company intends to introduce this new antibody into human testing.

FinancialWire(tm) is a fully independent, proprietary news wire service. FinancialWire(tm) is not a press release service, and receives no compensation for its news, opinions or distributions. Further disclosure is at the FinancialWire(tm) web site (http://www.financialwire.net/disclosures.php). Contact FinancialWire(tm) directly via inquiries@financialwire.net.

Free annual reports for companies mentioned in the news are available through the Free Annual Reports Service (http://investrend.ar.wilink.com/?level=279). Recently issued reports and/or recorded webcasts include Aria International Holdings, Inc. (OTCBB: ARAH), Continental Materials Corp. (AMEX: CUO), Darling International, Inc. (NYSE: DAR), Document Security Systems, Inc. (AMEX: DMC), and Juhl Wind, Inc. (OTCBB: JUHL).

Legal Disclaimer:

EIN Presswire provides this news content "as is" without warranty of any kind. We do not accept any responsibility or liability for the accuracy, content, images, videos, licenses, completeness, legality, or reliability of the information contained in this article. If you have any complaints or copyright issues related to this article, kindly contact the author above.