Overall survival analysis of phase 3 OlympiA study of adjuvant olaparib for germline BRCA1/2 mutated breast cancer

The multinational phase 3 OlympiA study randomized patients with BRCA1- or BRCA2-germline mutations and early-stage HER2-negative high-risk breast cancer after local therapy and neoadjuvant or adjuvant chemotherapy to olaparib or placebo. At the first interim analysis with 2.5 years of median follow-up, olaparib significantly improved the primary endpoint of invasive disease-free-survival and the secondary endpoint of distant DFS. The second prespecified interim analysis of the study has now been published. With median follow-up of 3.5 years, olaparib also improved the secondary endpoint of overall survival (HR 0.68; p=0.009), while improvements in IDFS and DDFS were sustained with similar effect size.