CPI-1205 is primarily used in the field of oncology as an investigational drug targeting certain types of cancer. It functions as a selective inhibitor of EZH2 (enhancer of zeste homolog 2), an enzyme involved in the regulation of gene expression through epigenetic mechanisms. Overactivity of EZH2 has been linked to the progression of various cancers, including lymphomas and solid tumors. The compound shows promise in clinical trials for treating relapsed or refractory B-cell lymphomas, such as follicular lymphoma and diffuse large B-cell lymphoma. By inhibiting EZH2, CPI-1205 helps restore normal gene expression patterns that control cell growth and apoptosis, potentially halting tumor progression. Its application is also being explored in combination therapies with other anticancer agents, such as immunotherapies or targeted drugs, to enhance treatment efficacy. Due to its targeted mechanism, CPI-1205 may offer a more precise approach with potentially fewer side effects compared to conventional chemotherapy.