ImmunoCellular Therapeutics has announced the presentation of data from the phase 1 clinical trial of ICT-121 in patients with recurrent glioblastoma. The data from the 20-patient, open-label, multi-center study show that 6 of 20 patients are alive (as of April 2017; survival ranging from 10 to 24 months), and these patients will continue to be followed. As noted in the data presentation, ICT-121 was generally safe and well tolerated.
As also noted, although diversity in patient disease severity resulting from a protocol amendment to expand patient eligibility makes interpretation of survival data difficult, the results are encouraging and warrant further investigation. Pending immune response data will provide insight into the potential effectiveness of ICT-121 in inducing the formation of cytotoxic T cells targeting CD133, a cancer stem cell marker. ICT-121 is a dendritic cell-based immunotherapy that specifically targets CD133 which is overexpressed in a wide variety of solid tumors, including glioblastoma as well as non-small cell lung, colon, ovarian, pancreatic and breast cancers.
The phase 1 data were presented by Jeremy D. Rudnick, MD, a neurologist in the Johnnie L. Cochran, Jr. Brain Tumor Center in the Department of Neurology at Cedars-Sinai, in a poster titled, "Immunological targeting of CD133 in recurrent glioblastoma: A multi-center Phase I translational and clinical study of autologous CD133 dendritic cell immunotherapy." The data were presented at the 53rd Annual Meeting of the American Society of Clinical Oncology (ASCO), taking place in Chicago.
"The preliminary findings from this phase 1 trial are encouraging, especially in light of the lethality of recurrent glioblastoma and lack of therapeutic options for patients with this disease," said Dr. Rudnick. "We look forward to continuing to follow the patients in this study, and believe that ICT-121 is a potentially promising cancer immunotherapeutic agent."
The phase 1 multi-center trial of ICT-121 targeting CD133 assesses safety and tolerability (primary endpoint) and monitors overall survival and progression-free survival (secondary endpoints). ICT-121 is comprised of autologous dendritic cells that are loaded with two HLA-A2 restricted epitopes of the CD133 antigen. After surgical resection, the HLA-A2-positive patients with recurrent glioblastoma were treated with ICT-121 once a week for 4 weeks during the induction phase and then once every 2 months during the maintenance phase until disease progression, death, ICT-121 depletion or discontinuation. In addition to safety and survival data, the phase 1 trial also assesses immune response by using an ELISpot assay and examining cytokine mRNA expression in response ICT-121 treatment.
"We are encouraged by the preliminary phase 1 results of ICT-121, which we believe underscore the potential of our DC-based approach to cancer immunotherapy," said Anthony J. Gringeri, PhD, ImmunoCellular president and chief executive officer. "We are grateful for the time and effort of the patients, investigators, and staff who supported this clinical study."