-- Interim Results Updated at 2016 AACR Annual Meeting --
-- Objective Response Rate (ORR) of 50%, 86% Confirmed –
-- Median Progression-Free Survival (PFS) of 6.9 Months, 47% Maturity --
-- Mean Overall Survival (OS) of 11.4 Months, 16% Maturity --
NEW ORLEANS, April 19, 2016 (GLOBE NEWSWIRE) -- Immunomedics, Inc. (Nasdaq:IMMU) today announced that sacituzumab govitecan, its lead investigational antibody-drug conjugate (ADC), produced meaningful clinical benefit in patients with relapsed or refractory metastatic urothelial cancer. Among the 19 patients enrolled into the open-label Phase 2 study, at the time of analysis the interim median PFS was 6.9 months, based on RECIST 1.1, and interim mean OS was 11.4 months, with 84% of patients still alive. Expression of Trop-2, a cell-surface protein targeted by the ADC, is not a pre-selection criterion for patient enrollment.
“To put these results with IMMU-132 in perspective, multiple chemotherapy regimens have been reported to produce PFS of 2 to 5 months and OS of 4 to 9 months in the second- or third-line setting of metastatic urothelial cancer1,” commented Scott T. Tagawa, M.D., Medical Director, Genitourinary Oncology Research Program, Weill Cornell Medicine/New York-Presbyterian Hospital, New York, NY, who presented the updated results at the AACR conference.
Of the fourteen assessable patients who had received a median of 2 (range, 1 – 5) prior lines of chemotherapy, seven patients reported a partial response as their best response, yielding an interim ORR of 50%. Importantly, six of the seven responding patients (86%) had been confirmed with a follow-up computed tomography (CT) scan, four of whom are continuing with their treatment.
As has been reported by us in patients with other types of solid cancer, sacituzumab govitecan also has an acceptable interim safety profile in 13 urothelial cancer patients reported at AACR. The notable adverse events were Grade 3 or 4 neutropenia and febrile neutropenia in 31% and 15% of patients, respectively. Severe diarrhea, commonly reported with irinotecan, was rare, with only 8% Grade 3/4 incidents. More importantly, repeated doses can be given over months without evoking interfering anti-sacituzumab govitecan antibodies from patients’ own immune system.
“We are very encouraged by these results in metastatic urothelial cancer, which warrant a regulatory strategy similar to triple-negative breast cancer should these results continue to be robust,” remarked Cynthia L. Sullivan, President and Chief Executive Officer. “Updated results in triple-negative breast and non-small-cell lung cancers will be presented at two Clinical Science Symposia during the upcoming ASCO Annual Meeting in June.”
Sacituzumab govitecan has received Breakthrough Therapy designation from the FDA for the treatment of patients with triple-negative breast cancer who have failed prior therapies for metastatic disease.
In addition to Dr. Tagawa, other Principal Investigators participated in this ongoing Phase 2 study in metastatic urothelial cancer include Drs. Bishoy Faltas and Allyson J. Ocean, his colleagues at Weill Cornell Medical College; Drs. Elaine Lam and Wells A. Messersmith, University of Colorado Cancer Center, Aurora, CO; Drs. Philip Saylor and Aditya Bardia, Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA; Dr. Julio J. Hajdenberg, UF Health Cancer Center-Orlando Health, Orlando, FL; Drs. Alicia K. Morgans and Jordan D. Berlin, Vanderbilt-Ingram Cancer Center, Nashville, TN; and Drs. Emerson Lim and Kevin Kalinsky, Columbia University-Herbert Irving Comprehensive Cancer Center, New York, NY.
About Metastatic Urothelial Cancer
More than 90% of urothelial cancer occur in the urinary bladder. According to the American Cancer Society’s estimates, urinary bladder cancer accounts for about 5% of all new cancers in the United States and is the fourth most common cancer in men, but less common in women. In 2012, an estimated 577,403 Americans were living with the cancer. In 2016, an estimate of 76,960 new cases of urinary bladder cancer will be diagnosed in this country.
While the majority of urinary bladder cancers originate from the uroepithelial surface, most patients who die from the malignancy do so from metastatic disease. In 2016, approximately 16,390 deaths from urinary bladder cancer are expected in the United States. Metastatic urothelial cancer patients have been reported in the medical literature to have a median overall survival of approximately 15 months.2 Cisplatin-based combination chemotherapy regimens, involving doxorubicin, gemcitabine, methotrexate, and/or vinblastine, are standard first-line treatments for eligible patients. To date, no standard therapy has been established in the second- or third-line setting. However, multiple Phase 2 studies, using a wide variety of chemotherapy regimens, have reported PFS in the range of 2 to 5 months and OS of 4 to 9 months.1
About Sacituzumab Govitecan
Sacituzumab govitecan, or IMMU-132, is a first-in-class ADC developed by the Company by conjugating the moderately-toxic drug, SN-38, site-specifically and at a high ratio of drug to hRS7, a humanized antibody that targets the Trop-2 receptor expressed by many solid cancers. SN-38 is the active metabolite of irinotecan (Camptosar), which is used to treat certain solid cancers as a part of combination therapies, so its pharmacology and properties are well-known. This ADC has received Breakthrough Therapy designation from the FDA for the treatment of patients with triple-negative breast cancer (TNBC) who have failed prior therapies for metastatic disease. The FDA has also granted IMMU-132 Fast Track designation for patients with TNBC, and for patients with small-cell lung cancer (SCLC) or non-small-cell lung cancer (NSCLC). Sacituzumab govitecan has also been designated an orphan drug by the FDA for the treatment of patients with SCLC or pancreatic cancer in the U.S. and by the European Medicines Agency (EMA) for the treatment of patients with pancreatic cancer in the European Union.
References
- Sonpavde G, Sternberg CN, Rosenberg JE, et al. Second-line systemic therapy and emerging drugs for metastatic transitional-cell carcinoma of the urothelium. The Lancet Oncology. 2010. pp. 861–870.
- Abida W, Bajorin DF, Rosenberg JE. First-Line treatment and prognostic factors of metastatic bladder cancer for platinum-eligible patients. Hematol Oncol Clin North Am. 2015 Apr;29(2):319-28, ix-x.
About Immunomedics
Immunomedics is a clinical-stage biopharmaceutical company developing monoclonal antibody-based products for the targeted treatment of cancer, autoimmune disorders and other serious diseases. Immunomedics’ advanced proprietary technologies allow the Company to create humanized antibodies that can be used either alone in unlabeled or “naked” form, or conjugated with radioactive isotopes, chemotherapeutics, cytokines or toxins. Using these technologies, Immunomedics has built a pipeline of eight clinical-stage product candidates. Immunomedics’ portfolio of investigational products includes antibody-drug conjugates (ADCs) that are designed to deliver a specific payload of a chemotherapeutic directly to the tumor while reducing overall toxic effects that are usually found with conventional administration of these chemotherapeutic agents. Immunomedics’ most advanced ADCs are sacituzumab govitecan (IMMU-132) and labetuzumab govitecan (IMMU-130), which are in Phase 2 trials for a number of solid tumors and metastatic colorectal cancer, respectively. IMMU-132 has received Breakthrough Therapy Designation from FDA for the treatment of patients with triple-negative breast cancer who have failed at least 2 prior therapies for metastatic disease. Immunomedics has a research collaboration with Bayer to study epratuzumab as a thorium-227-labeled antibody. Immunomedics has other ongoing collaborations in oncology with independent cancer study groups. The IntreALL Inter-European study group is conducting a large, randomized Phase 3 trial combining epratuzumab with chemotherapy in children with relapsed acute lymphoblastic leukemia at clinical sites in Australia, Europe, and Israel. Immunomedics also has a number of other product candidates that target solid tumors and hematologic malignancies, as well as other diseases, in various stages of clinical and preclinical development. These include combination therapies involving its antibody-drug conjugates, bispecific antibodies targeting cancers and infectious diseases as T-cell redirecting immunotherapies, as well as bispecific antibodies for next-generation cancer and autoimmune disease therapies, created using its patented DOCK-AND-LOCK® protein conjugation technology. The Company believes that its portfolio of intellectual property, which includes approximately 287 active patents in the United States and more than 400 foreign patents, protects its product candidates and technologies. For additional information on the Company, please visit its website at www.immunomedics.com. The information on its 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 (including the funding therefor, outcomes, timing or associated costs), 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, new product development (including clinical trials outcome and regulatory requirements/actions), the Company’s dependence on business collaborations in order to further develop our products and finance our operations, the risk that we or any of our collaborators may be unable to secure regulatory approval of and market our drug candidates, risks associated with the outcome of pending litigation and 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.