Objectives. The objective of this study was to determine the overall tolerability and toxicity of olaparib capsules among older (>= 65 years) patients with recurrent ovarian cancer treated on 8 completed prospective trials of olaparib. Methods. An ancillary data analysis of 398 patients with recurrent ovarian cancer enrolled on eight prospective trials of olaparib capsules was performed. Patients aged 65 years and older were stratified into age groups by 5 year increments (ages 65-69, 70-74, >= 75 years) and compared to those < 65. Analysis was restricted to those patients receiving the recommended treatment dose of 400 mg PO b.i.d. Results. Of the 398 patients included, 78 were >= 65 (age 65-69 n = 38, age 70-74 n = 23, age >= 75 n = 17). The majority of elderly patients were Caucasian (n = 2 Asian) and had received ?.5 prior lines of chemotherapy. In patients < 65, 46.9% required dose reduction as compared to 44.7% of patients 65-69 years, 47.8% of patients 70-74 years, and 64.7% of patients >= 75 years (p = 0.62). In patients < 65 years 41.2% required dose interruption, as compared to 50%, 43.5%, and 64.7% of patients aged 65-69, 70-74, and >= 75, respectively (p = 0.11). There were no occurrences of myelodysplastic syndrome or acute myeloid leukemia in any of the older cohorts. Toxicities, including grade 3/4 nausea, were similar across age groups. Conclusions. Tolerability and toxicity of olaparib capsules is similar between women >= 65 years and < 65 years of age treated for advanced recurrent ovarian cancer. Use of olaparib should be considered in this patient population. (C) 2017 Elsevier Inc. All rights reserved.