capecitabine + olaparib

Capecitabine + olaparib refers to a treatment regimen involving the antimetabolite capecitabine and the PARP inhibitor olaparib, specifically within the context of the PLANET trial (NCT05263986) led by the Netherlands Cancer Institute. In this Phase III pragmatic trial, these two agents constitute the standard-of-care (SoC) adjuvant therapy for patients with early-stage triple-negative breast cancer (TNBC) who have residual disease following neoadjuvant chemotherapy and pembrolizumab. It is important to note that in the PLANET trial, these drugs are typically used as alternative options rather than a concurrent combination: capecitabine is the standard for most patients, while olaparib is reserved for those with germline BRCA mutations. Capecitabine is an oral prodrug of 5-fluorouracil that inhibits thymidylate synthase, thereby blocking DNA synthesis. Olaparib is an oral small molecule that inhibits PARP1, PARP2, and PARP3, enzymes essential for DNA single-strand break repair, leading to cell death in homologous recombination-deficient tumors.