Based on a search of the ClinicalTrials.gov registry using the search terms “multiple myeloma” and “chimeric antigen receptor” or “CAR” (final date of search May 1, 2019), numerous studies of CD138-targeted CAR-T cell therapy in combination with other CARs are ongoing or planned (NCT03196414, NCT03473496, NCT03271632). This evidence concerns the gene SDC1 and plasma cell myeloma.