“Immunomedics, Inc. (Nasdaq: IMMU) today announced that patients with metastatic triple-negative breast cancer (TNBC) lived for a median of seven months without tumor progression, after receiving at least 3 doses of sacituzumab govitecan, the Company’s lead investigational antibody-drug conjugate (ADC) for solid cancer therapy, in a Phase 2 clinical study. The study also indicated that the responses were very durable, showing a median time-to-progression, based on computed tomography, of 9.4 months (range of 1.8+ to 13.2+ months), which included patients with stable disease, and partial and complete responses.
” ‘Patients in this late-stage setting usually have a median PFS of three to four months when treated with other agents,’ stated Aditya Bardia, MD, MPH, Assistant Professor of Medicine at Harvard Medical School, Attending Physician at the Massachusetts General Hospital Cancer Center in Boston, and an investigator in this trial. ‘Sacituzumab govitecan is a promising agent that offers hope for these patients with poor prognosis,’ Dr. Bardia added.”
“Immunomedics, Inc., (IMMU) today announced that among 49 patients with metastatic triple-negative breast cancer (TNBC) evaluated for response to treatments with sacituzumab govitecan in a mid-stage clinical study, 31%, or 15 patients, showed a reduction in tumor size of 30% or more. They include 2 patients with complete response. Response assessments were based on the rules set by the Response Evaluation Criteria In Solid Tumors (RECIST 1.1). Adding the 22 patients with responses between less than 30% tumor shrinkage and less than 20% tumor increase, the disease control rate was 76%.
“Sacituzumab govitecan also produced significant duration of response in these responding patients. Measured as the time it takes from the beginning of sacituzumab govitecan treatments to when the cancer progresses, the median progression-free survival (PFS) for the 48 patients who received the optimal doses of 8 or 10 mg/kg was 6.0 months. Importantly, 63% of patients (22 of 35) had a time-to-progression longer than their last therapy, notwithstanding disease progression has not yet happened in 56% of patients at the time of analysis.
“These results were presented at the 2015 Annual Meeting of the American Society of Clinical Oncology by Dr. Aditya Bardia of Massachusetts General Hospital Cancer Center in Boston, MA, and a faculty member at Harvard Medical School, who commented, ‘Given that a majority of the patients enrolled into this study had failed 4 or more prior cancer therapies, some as many as 11, we are quite encouraged with sacituzumab govitecan in this late-stage setting in an aggressive disease that is difficult to treat.’ “
“The FDA granted fast track designation to sacituzumab govitecan for the treatment of patients with metastatic non–small cell lung cancer, according to a press release from the drug’s manufacturer.
“Sacituzumab govitecan (IMMU-132, Immunomedics) — a next-generation antibody-drug conjugate of the moderately toxic drug SN-38, the active metabolite of irinotecan — is intended for patients with metastatic NSCLC who have failed two prior lines of therapy, such as ALK, EGFR and PD-1 inhibitors.
“Sacituzumab govitecan has shown promise in a mid-stage clinical study for patients with metastatic solid cancers — including breast, lung, esophageal, colorectal, and urinary bladder cancers — who failed multiple prior therapies. Patients experienced limited and tolerable side effects, according to the press release.
“Previously, the FDA granted fast track status to sacituzumab govitecan for the treatment of patients with triple-negative breast cancer and small-cell lung cancer. In addition, sacituzumab govitecan received FDA orphan drug designation for the treatment of small-cell lung cancer and pancreatic cancer.”
“Immunomedics, Inc., (Nasdaq:IMMU) today announced that 33% of patients with small cell lung cancer (SCLC) and 31% with non-small cell lung cancer (NSCLC) had their tumor reduced in size by 30% or more, after being treated with sacituzumab govitecan, the Company’s lead investigational antibody-drug conjugate (ADC). Including patients that reported stable disease as their best response, the ADC controls the progression of the cancer in 75% and 56% of NSCLC and SCLC patients, respectively. These patients had either failed to respond to their last lung cancer therapies or their cancer had returned or progressed.
“Dr. Francois Wilhelm, Chief Medical Officer, presented the updated results at the 15th Annual Targeted Therapies of Lung Cancer Meeting, an invitation-only meeting sponsored by The International Association for the Study of Lung Cancer (IASLC).
“Sacituzumab govitecan is a next generation ADC designed for targeted therapy of solid cancers. The agent was created by site-specifically conjugating a TROP-2-targeting antibody with a high ratio of a moderately toxic drug, SN-38, using a pH sensitive linker. TROP-2 is a receptor found on many human cancer cells, such as cancers of the breast, cervix, colon and rectum, kidney, liver, lung, ovary, pancreas, and prostate, but with only limited expression in normal human tissues. In an animal model of human pancreatic cancer, the ADC delivered up to 135-times the amount of SN-38 to the tumor than when irinotecan, the parent drug of SN-38, was given.”
The gist: The U.S. Food and Drug Administration (FDA) has granted a “Fast-Track” designation to a new treatment for people with metastatic, triple-negative breast cancer who haven’t had success with their previous treatments. The treatment is called sacituzumab govitecan (aka IMMU-132). The Fast-Track designation means that the FDA will facilitate a faster approval process so that the treatment can soon be prescribed by oncologists in the U.S.
“The FDA today granted fast track status to sacituzumab govitecan, an antibody–drug conjugate in development for treatment of patients with triple-negative breast cancer who failed prior therapies for metastatic disease, according to the drug’s manufacturer.
“Sacituzumab govitecan (IMMU-132, Immunomedics) is formed by using the moderately-toxic SN-38 — the active metabolite of irinotecan (Camptosar; Pfizer), used to treat certain solid tumors — conjugated to an anti–TROP-2 antibody.
“The FDA’s Fast Track program is intended to facilitate the development and expedite the review of new drugs intended to treat serious conditions, as well as agents that would fill unmet medical needs.
“The FDA based its decision on the efficacy sacituzumab govitecan has shown in patients with advanced triple-negative breast cancer.
The gist: A drug called sacituzumab govitecan has shown promising results in a clinical trial in patients with metastatic triple-negative breast cancer (TNBC) who have taken previous treatments. In the trial, patients generally experienced a longer period of time without their cancer worsening when they took sacituzumab govitecan compared to when they took their last treatment for TNBC.
“Immunomedics, Inc., (Nasdaq:IMMU) today announced that sacituzumab govitecan, the Company’s novel investigational antibody-drug conjugate (ADC), continues to produce a partial response (PR) rate of 30% and a 70% clinical benefit rate (CBR), defined as PR and stable disease, in patients with metastatic triple-negative breast cancer (TNBC) who had been heavily pretreated. For patients with PR or stable disease longer than 6 months, the CBR was 40%. Significantly, PRs ranging from 30% to 70% tumor shrinkage as best response were reported. Responses are measured by computed tomography (CT) based on RECIST 1.1 criteria.
“Dr. Aditya Bardia of Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, presented the Phase 1/2 study at the San Antonio Breast Cancer Symposium in San Antonio, TX. Commenting on the results, Dr. Bardia stated, ‘TNBC patients in this late-stage setting have limited treatment options that are effective. We are quite encouraged with this experience with sacituzumab govitecan, especially the time-to-progression results, which showed that the duration of response for the responding patients was generally longer than their last prior therapy for TNBC.’ ”
“As the name implies, TNBC represents breast cancers that are negative for estrogen and progesterone receptors, as well as human epidermal growth factor receptor 2, or HER2. This type of breast cancer comprises about 15-20% of all invasive breast cancers and is more prevalent in young and African-American women. Despite the fact that initial responses with chemotherapy are high, TNBC characteristically has a high recurrence rate and is perhaps the most difficult type of breast cancer to treat successfully with current cytotoxic agents. According to a published report, the median survival for patients with metastatic triple-negative breast cancer is estimated to be 13 months. 1 Currently, there are no targeted treatments available for TNBC.”