UCLA researchers reported a next‑generation CAR‑T design engineered to resist the immunosuppressive microenvironment of solid tumors, and Calidi Biotherapeutics disclosed preclinical characterization of CLD‑401, an oncolytic vaccinia vector engineered for tumor specificity. Both programs aim to overcome barriers that have limited cell‑based therapies in solid malignancies—immune suppression, delivery, and tumor heterogeneity—and were presented with early efficacy and mechanism data at recent scientific meetings. CAR‑T refers to T cells genetically modified to express chimeric antigen receptors; oncolytic vectors are engineered viruses that selectively infect and kill tumor cells while stimulating local immunity.