In April, MesotheliomaHelp reported that an immunotherapy drug being tested for the treatment of pleural mesothelioma had such positive Phase 1b trial results that the company would “advance directly to a Phase 3 clinical trial.” Now, the company reports continued encouraging results with the immunotherapy drug known as CRS-207 in its ongoing Phase 1b trial.
In a Nov. 12 press release from Aduro-Biotech, the company reported on its preliminary findings of the second cohort of its multi-center, Phase 1b mesothelioma clinical trial. The results of the trial, designed to assess the efficacy of CRS-207 when used in combination with chemotherapy drugs pemetrexed and cisplatin for patients with malignant pleural mesothelioma, were announced at the Annual Meeting of the Society for Immunotherapy of Cancer held Nov. 9-13 in National Harbor, Maryland. The positive results came with a one-percent increase in the company’s shares pre-market Monday, Nov. 13.
Initial results of a 22 patient cohort, with more advanced disease than those tested in the first round, included: 82% of patients had disease control, with 55% achieving a partial response, and 27% with stable disease; and tumor shrinkage was observed in 77% of patients. The results were reported following treatment with CRS-207 in combination with standard of care chemotherapy and immune-modulating doses of cyclophosphamide as a first-line treatment.
“We believe these data, together with the results from the first cohort, support further investigation of CRS-207 in mesothelioma, and we intend to initiate a Phase 2 study of CRS-207 used in combination with an anti-PD-1 therapy as an immune-modulator in patients with mesothelioma who have failed at least one prior therapy,” said Dirk G. Brockstedt, Ph.D., executive vice president of research and development of Aduro.
CRS-207 is a Listeria-based vaccine that has been engineered to induce immune system T cells to target cancer cells that express mesothelin. Mesothelin is a protein found in higher amounts in certain types of cancer cells including mesothelioma, non-small-cell lung cancer and pancreatic cancer.
Malignant pleural mesothelioma is a cancer of the lining of the chest cavity caused by exposure to asbestos. Approximately 2,500 to 3,000 people are diagnosed with mesothelioma each year in the U.S. Most are older workers, retired workers and veterans exposed to airborne asbestos fibers at a workplace decades ago. Mesothelioma takes decades to appear after exposure, but then advances rapidly.
Aduro Biotech, Inc. is a private, clinical-stage immuno-oncology company focused on the development of technology platforms to stimulate an immune response against cancer.