Abstract 58P
Background
In China, ovarian cancer (OC) is the leading cause of death among gynecological cancers. Clinical trials showed that olaparib maintenance therapy was effective and well-tolerated in OC patients (pts). Yet, real-world safety data of olaparib in a broad Chinese population are limited. DIM-OC aims to intensively monitor the safety of olaparib in the largest Chinese OC cohort.
Methods
This multicenter, prospective, observational study enrolled OC pts who had received ≥1 dose of olaparib. Primary endpoints included the incidences of adverse events (AEs), serious AEs (SAEs) and AEs of special interest (AESIs) during the follow-up (up to 30 days after olaparib discontinuation or maximally for 6 months after enrolment), and were reported with the Clopper-Pearson 95% CIs.
Results
799 pts from 33 sites were enrolled by 30 Jun 2023, and 796 pts treated with olaparib were analyzed by data cut-off (29 Dec 2023). At baseline, the mean age was 56±9 years. 490 (61.6%) and 306 (38.4%) pts had newly diagnosed and platinum-sensitive relapsed OC, respectively. 343 (43.1%, 95% CI [39.6%, 46.6%]) reported ≥1 AEs and 257 (32.3%, 95% CI [29.0%, 35.7%]) had ≥1 treatment-related AEs (TRAEs) as per investigator assessment (Table). Most common TRAEs included anemia (n=137, 17.2%), white blood cell count decreased (n=79, 9.9%) and neutrophil count decreased (n=59, 7.4%). Grade ≥3 AEs occurred in 68 (8.5%, 95% CI [6.7%, 10.7%]) pts, grade ≥3 TRAEs in 52 (6.5%, 95% CI [4.9%, 8.5%]), SAEs in 27 (3.4%, 95% CI [2.2%, 4.9%]), and AESIs in 3 (0.4%, 95% CI [0.1%, 1.1%]). For AESIs, myelodysplastic syndrome, breast cancer and pneumonitis each occurred in 1 pt (0.1%, 95% CI [0.0%, 0.7%]). 21 (2.6%, 95% CI [1.6%, 4.0%]) pts discontinued treatment due to AEs. No new safety signals were detected. Table: 58P
| n (%) | Olaparib (N=796) | 95% CI | |
| ≥1 AEs | 343 (43.1) | 39.6%, 46.6% | |
| ≥1 treatment-related AEs | 257 (32.3) | 29.0%, 35.7% | |
| Grade ≥3 AEs | 68 (8.5) | 6.7%, 10.7% | |
| Grade ≥3 treatment-related AEs | 52 (6.5) | 4.9%, 8.5% | |
| SAEs | 27 (3.4) | 2.2%, 4.9% | |
| Treatment-related SAEs | 10 (1.3) | 0.6%, 2.3% | |
| AEs leading to treatment discontinuation | 21 (2.6) | 1.6%, 4.0% | |
| Treatment-related AEs leading to treatment discontinuation | 16 (2.0) | 1.2%, 3.2% | |
| AEs occurring in >5% of patients | Overall | Grade 1 or 2 | Grade 3 or 4 |
| Anemia | 153 (19.2) | 110 (13.8) | 43 (5.4) |
| White blood cell count decreased | 88 (11.1) | 81 (10.2) | 7 (0.9) |
| Neutrophil count decreased | 67 (8.4) | 59 (7.4) | 8 (1.0) |
| Platelet count decreased | 49 (6.2) | 45 (5.7) | 4 (0.5) |
Conclusions
Olaparib showed acceptable and tolerable safety profile in this largest to date, real-world Chinese OC cohort, regardless of treatment lines. No new safety signals were detected.
Clinical trial identification
NCT04560452.
Editorial acknowledgment
Medical writing support for the development of the abstract, under the input and direction of the authors, was provided by Xiaowei Ning from Costello Medical Singapore and funded by AstraZeneca China.
Legal entity responsible for the study
AstraZeneca.
Funding
AstraZeneca.
Disclosure
All authors have declared no conflicts of interest.