Sonia Guedan, PhD, August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain, discusses novel strategies used to improve CAR T-cells in solid tumors. One of the approaches involves the combination of CAR T-cells with oncolytic adenoviruses to revert tumor immunosuppression. To improve CAR T-cell persistence in the tumor microenvironment, the intracellular domains of the CAR can be changed. Finally, to avoid toxicities the affinity of the single-chain variable fragment can be lowered. This interview took place at the 2nd European CAR T-Cell Meeting in Sitges, Spain.