CAR-M is a therapy that begins with the isolation of primary monocytes from a patient’s blood, which are then modified with the desired antigen-specific chimeric receptor, such as anti-HER2. The resulting CAR-M modified cells are cryopreserved and will be reinjected into the patient. CAR-Ms may be able to reach immunologically “cold” tumors to activate them to better respond to treatment. Preliminary data from the multi-center Phase 1 human clinical trial of CAR-M targeting HER2-positive recurrent or metastatic solid tumors were presented at the recent Society for Immunotherapy of Cancer conference. Preliminary data demonstrated that CAR-M therapy (CT-0508) has the ability to alter the microenvironment of solid tumors and change the composition of myeloid cells and T cells. This innovative immunotherapy advances scientific discovery for solid cancer tumors and offers a promising new strategy in the fight against cancer. These results also represent the first clinical data with genetically engineered macrophages in humans. The Food and Drug Administration recently granted Fast Track designation to CT-0508 for clinical trials evaluating the efficacy and safety of the treatment in patients with solid tumors.