Introduction/Background Patients with advanced epithelial ovarian cancer (EOC) have a poor prognosis. The Olaparib significantly prolonged their progression-free survival (PFS). However, its tolerability in Asian population and the role of low dose in real-world practice was not well-reported.

Methodology Patients with primary or recurrent EOC using Olaparib in February, 2019 – July, 2023 were recruited in this study. Their clinical characteristics, including side effects graded by the CTCAE 5.0 and survival data evaluated by Kaplan-Meier curves, were reviewed retrospectively.

Results 21 patients received Olaparib for advanced EOC. The median age was 60 years (range 37 – 75 years) and the median body weight was 53kg (range 38.0 - 83.4kg). All patients started with 300mg tablets BD, except two who started with 250mg tablets. 13 patients (61.9%) required drug interruption, which occurred as early as 1.5 months (range 0.7 – 9.5 months) after initiation of Olaparib. 14 patients (66.7%) required dose reduction occurring 1.8 months (range 0.8 – 9.9 months), and 9 (42.9%) required a second dose reduction to 200mg BD after a median of 3 months (range 1.4 – 12.5 months). Although not included in most studies, 6 patients (28.6%) reduced the dose to 150mg BD, where 2 was due to anemia, 2 due to thrombocytopenia and 2 due to elevated creatinine. Median PFS and overall survival were not reached yet, but patients with 150mg BD did not have a higher recurrence rate compared to patients using the standard dose (16.7% vs 13.3%; p = 0.658).

Conclusion Our population had a high drug interruption/dosage modification rate. Although it is usually recommended to terminate Olaparib if patients cannot tolerate 200mg BD, a lower dosage of 150mg BD may still show beneficial effects in our cohort. A longer follow-up period and a larger cohort are needed to prove the value of this dosage.

Disclosures I have no potential conflict of interest to report.