Rucaparib is primarily used in the treatment of certain types of cancer, particularly ovarian cancer, fallopian tube cancer, and primary peritoneal cancer. It is especially effective in patients who have specific genetic mutations, such as BRCA1 or BRCA2. The drug works by inhibiting the PARP enzyme, which plays a crucial role in repairing DNA damage. By blocking this enzyme, Rucaparib prevents cancer cells from repairing their DNA, leading to their death. This targeted approach makes it a valuable option for patients with advanced or recurrent cancers who have limited treatment alternatives. Additionally, Rucaparib is sometimes used as a maintenance therapy to help prevent cancer from returning after initial treatment. Its ability to selectively target cancer cells with minimal impact on healthy cells has made it a significant advancement in precision medicine for cancer treatment.