CAR-T Cell Therapy: A Novel Approach in Cancer Treatment and Current Limitations. Arindam Dasgupta State Aided College Teacher (SACT 1) Vivekananda College for Women, Kolkata Department of Zoology. Email- arindamdsgpta12@gmail.com Phone- 09831249716. Abhishikta Ghosh Roy Superintending Anthropologist Anthropological Survey of India Ministry of Culture Government of India. ABSTRACT Chimeric Antigen Receptor (CAR)-T cell therapy is a cutting edge, completely original and arguably the most complex cancer therapy ever invented to cure cancer, especially B cell leukemia. However, hundreds of studies are currently investigating its use in other cancer types. It's a combination of gene therapy, where a DNA is edited to remove a defective gene or to insert a target gene, and immunotherapy, which boosts a patient's natural immune system. Customized DNA constructs are delivered to patients’ T lymphocytes where they express specific engineered receptors against the specific target antigens on malignant cells. It is a ‘living drug' engineered from the patient's own lymphocytes for better targeting and killing their own cancer cells. Such a single crafted immune cell can kill more than a thousand malignant cells. However, there are major limitations in the application of this therapy which includes severe side effects, both temporary and long term, specially by the release of cytokines causing inflammatory reactions. In addition, studies have also revealed the relapse of cancer in one of three cases or more. The primary cause is developing resistance against CAR-T by evolving new or shedding surface markers among many. Challenges still limit the use of this therapy against solid tumors of lung, colon, breast and prostate. Moreover, large work forces are needed to be properly trained to carry out this complex procedure efficiently, which is always going to be a major challenge in many countries. Other challenges remain to be cell associated toxicity, immunosuppressive microenvironment, cell trafficking etc. Here, we review the in-depth concept design, recent innovations and mechanism of action along with the pressing hurdles around the therapy and the strategies to overcome the limitations. Keywords- CAR-T Cell, Gene Therapy, Immunotherapy.