Background	9 Months Ended
Background	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Background	Background Carisma Therapeutics Inc., a Delaware corporation (collectively with its subsidiaries, the Company), is a clinical-stage cell therapy company focused on using the Company’s proprietary cell therapy platform to develop transformative immunotherapies to treat cancer and other serious diseases. The Company has created this comprehensive cell therapy platform to enable the therapeutic use of engineered macrophages and monocytes, which belong to a subgroup of white blood cells called myeloid cells. The Company’s focus is its proprietary chimeric antigen receptor macrophage and monocyte (CAR-M) cell therapy platform, which redirects macrophages against specific tumor associated antigens and enables targeted anti-tumor immunity by utilizing genetically modified myeloid cells (macrophages and monocytes) to express chimeric antigen receptors (CARs), enabling these potent innate immune cells to recognize specific tumor associated antigens on the surface of tumor cells. The Company has an ex vivo oncology program and an in vivo program. In addition, the Company utilizes its cell therapy platform to engineer macrophages with the potential to treat fibrosis. Ex Vivo Oncology Program — The Company's lead product candidate, CT-0525, is intended to treat solid tumors that overexpress human epidermal growth factor receptor 2 (HER2), a protein found on the surface of a variety of solid tumors, including breast cancer, gastric cancer, esophageal cancer, salivary gland cancer, and others. CT-0525 utilizes a novel approach to CAR-M therapy that engineers patients’ monocytes directly, without ex vivo differentiation into macrophages. The Company believes that engineering monocytes directly (CAR-Monocyte) will result in a therapy with favorable attributes compared to engineering after ex vivo differentiation (CAR-Macrophage) and that this approach has the potential to improve upon the anti-tumor effect seen with CAR-Macrophages. In Vivo Program (Moderna Collaboration) — In addition to the Company's clinical program in ex vivo cell therapy, the Company has an in vivo mRNA/lipid nanoparticle (LNP) CAR-M program in partnership with ModernaTX Inc. (Moderna). This collaboration utilizes Moderna's mRNA/LNP technology, together with the Company's CAR-M platform technology, to create novel in vivo off the shelf gene therapy products. Fibrosis Program — Using its macrophage and monocyte engineering platform, the Company is also pursuing early research and development of multiple assets for the potential treatment of diseases beyond oncology, including fibrosis and other immunologic and inflammatory diseases. In the second quarter of 2024, the Company achieved pre-clinical proof of concept in its liver fibrosis program, demonstrating the anti-fibrotic potential of engineered macrophages in two liver fibrosis models. The Company's first product candidate to enter clinical development, CT-0508, was the first CAR-Macrophage to be evaluated in a human clinical trial and was an anti-HER2 product candidate. The Company also enrolled six patients in a sub-study evaluating the co-administration of CT-0508 and pembrolizumab, a programmed cell death protein 1 checkpoint inhibitor, evaluating the safety and tolerability of the co-administration, along with several customary secondary endpoints. In late March 2024, the Company and its board of directors approved a revised operating plan to reduce monthly operating expenses and conserve cash, which it began implementing in April 2024. Pursuant to the revised operating plan, the Company has prioritized CT-0525 as the Company's lead product candidate going forward, ceased further development of CT-0508, paused further development of CT-1119 pending additional financing, reduced its workforce, including employees engaged in research and development and general and administration activities, and decreased spending on other non-essential activities. As of July 2024, all clinical activities related to the Phase 1 clinical trial of CT-0508 and its sub-study utilizing CT-0508 in combination with pembrolizumab have been completed and no further development of CT-0508 is planned. The Company completed its workforce reduction and paid the majority of related costs in the second quarter of 2024.