Measles Virus Vaccine Under Study in Multiple Myeloma
Posted: Monday, June 29, 2020
The antimyeloma T-cell response appears to be strengthened in patients with multiple myeloma after receiving the oncolytic virotherapy known as measles virus–encoding sodium iodide symporter (MV-NIS), according to the results of a recent study published in Leukemia. Stephen J. Russell, MD, PhD, of the Mayo Clinic, Rochester, Minnesota, and colleagues suggested this amplified immune response may support long-term tumor remission when used in combination with other immunomodulatory drugs.
“MV-NIS uses CD46 receptors to enter cells and to drive intercellular fusion of infected cells with their uninfected neighbors, resulting in formation of nonviable multinucleated syncytia,” the investigators commented. “Myeloma plasma cells overexpress CD46 and are therefore highly susceptible to MV-NIS killing.”
A total of 10 patients with multiple myeloma who were enrolled in a phase I trial of MV-NIS completed the study. The patients were administered a single intravenous infusion of 1011TCID50 infectious units of MV-NIS. Peripheral blood mononuclear cell samples were obtained before and after 6 weeks of virotherapy. The investigators performed a series of assays to determine whether the patients had existing cytotoxic T-cell activity against 10 preselected tumor-associated antigens and whether oncolytic virotherapy heightened this response. In addition, blood samples from healthy volunteers were cryopreserved as peripheral blood mononuclear cells.
Based upon the analysis of the samples collected before virotherapy, more than 50% of the patients with myeloma displayed T-cell responses against MAGE-C1, hTERT, MAGE-A3, and NY-ESO-1. The T-cell responses against these tumor-associated antigens were significantly stronger in patients with myeloma than in the healthy controls (P < .05). After intravenous MV-NIS infusion, the T-cell responses against MAGE-A3 and MAGE-C1 were significantly amplified (P < .05). One patient, who presented with high counts of measles-reactive and tumor antigen-reactive cytotoxic T cells at baseline, achieved long-term complete remission.
Disclosure: The study authors reported no conflicts of interest.