Evaluating the Efficacy and Safety of PARP Inhibitors in BRCA-Mutated Triple Negative Breast Cancer- A Systematic Review

Introduction: TNBC is a subtype of breast cancer that accounts for 10-15% of instances and is distinguished by the lack of HER2overexpression, progesterone receptors, and oestrogen receptors. Compared to other kinds of breast cancer, TNBC is moreaggressive, has a worse prognosis and survival rate, and can only be treated with chemotherapy. In cancer cells with BRCAmutations, PARP inhibitors target the PARP enzyme in DNA repair, accumulating DNA damage and causing cell death. Theobjective of a systematic review was to assess the efficacy and safety of PARP inhibitors in the management of TNBC withBRCA mutations. Objective response rates and outcomes like overall survival and progression-free survival were evaluated.Methods:The purpose of the systematic review is to evaluate how well PARP inhibitors, work to treat triple negative breastcancer. The Cochrane library and PubMed were searched for pertinent research, and the search period was from 2012 to 2022.Phase 2 and 3 randomised clinical trials examining the effectiveness of PARP inhibitors alone or in combination with othertreatments and reporting progression-free survival, overall survival, and objective response rate met the inclusion criteria for thestudies. Preclinical studies, single-arm studies, trials without information on BRCA status, case reports, and studies conducted inlanguages other than English were excluded. The JADAD score was used to evaluate the trials that were chosen. Patientcharacteristics, treatment modalities, and efficacy results were among the data retrieved from the research.Results:When compared to the control group, patients using PARP inhibitors demonstrated statistically significant improvementsin progression-free survival (PFS). However, there were no appreciable differences in overall survival (OS). The effectiveness ofthe PARP inhibitors varied among patient demographics and subgroups. Anemia, tiredness, and nausea were the most oftenreported side effects. In comparison to the control group, veliparib was linked to a greater incidence of anaemia and nausea. Inboth groups, a similar number of patients experienced serious adverse effects.Discussion:The effectiveness of PARP inhibitors as monotherapy or in combination with carboplatin-paclitaxel has been shownin evaluated studies. Anemia, tiredness, and nausea were the most frequent adverse effects, and severe hematologic toxicities wereof particular concern. However, future negative outcomes can be avoided by routine blood counts and the restriction of somePARP inhibitors to individuals who have recovered from hematologic toxicity. Patients with mutations in particular HR-relatedgenes did not react to olaparib therapy, however some subsets of breast cancer and other cancers such as prostate cancer, mayrespond favourably to PARP inhibitors. The systematic review has shortcomings such research diversity and a dearth of trials withsufficient power, which can reduce the dependability of results.Conclusion:PARP inhibitors have been proven in clinical trials to be beneficial in treating BRCA mutant TNBC, resulting inobjective responses and complete/partial remissions. They have a good safety profile, with the majority of side effects being mildto moderate. Despite the increased risk of myelosuppression, PARP inhibitors are a viable treatment option for patients withBRCA mutant TNBC. More research is required to completely comprehend optimal use and long-term advantages.