ODM-203 is used as a selective inhibitor of BET (bromodomain and extra-terminal) proteins, which play a key role in the regulation of gene expression linked to cancer progression. It is primarily investigated for its potential in oncology, especially in the treatment of solid tumors and hematological malignancies. By blocking BET bromodomains, ODM-203 disrupts the transcription of oncogenes such as MYC, thereby inhibiting tumor cell growth and proliferation. It has shown promise in preclinical models for prostate cancer, leukemia, and other cancers dependent on dysregulated transcriptional programs. ODM-203 is being evaluated in early-phase clinical trials to assess its safety, pharmacokinetics, and anti-tumor activity in humans. Its development represents a targeted epigenetic therapy approach aimed at cancers with limited treatment options.