5587 Background: Bevacizumab (bev) may be part of first-line treatment for patients with “high-risk” epithelial ovarian cancer (OC) (GOG-0218 and ICON7 trials). The prevalence of high-risk patient subgroups, including bev use and its effect on survival in a real-world setting is not well studied. Methods: The observational multi-country cohort study RESPONSE collected retrospectively medical record data on women with newly diagnosed advanced high-grade serous or endometrioid OC (DOI: 10.1002/cncr.34350). We analysed patients defined as ‘high-risk’ according to ICON7 definition as either 1) stage IV disease, 2) inoperable stage III disease or 3) sub-optimally debulked (>1 cm residual disease) stage III disease. Unadjusted Cox proportional hazards regression analysis was performed to estimate the association of bev with the risk of death. Follow up time was calculated from time between response assessment at the end of primary chemotherapy and death or 20 months follow-up, whichever occurred first. Results: Of 954 patients in total, we identified 386 high-risk patients (40%) treated with platinum-based chemotherapy. Of these, 132 (34%) received bev maintenance treatment. Baseline characteristics did not differ between patients receiving bev or no bev. Bev use was associated with a statistically significant reduction in risk of death with a HR of 0.49 (95%Ci: 0.18-0.78, p=0.002) in the total group of high-risk patients. The effect on survival was most evident among inoperable stage III/IV patients (n=151) with a 63% reduction in risk of death (HR 0.37; 95% CI (0.18-0.78, p=0.009). Risk estimates for additional subgroups are given in the table. Conclusions: Forty percent of this real-world population are considered high-risk according to ICON-7 and a majority of these patients did not receive bev during first-line treatment. In line with ICON 7, this analysis supports the beneficial effect of bev on overall survival in this high-risk population. Patients who do not receive surgery are underrepresented in clinical trials and this real-world study confirms the strong benefit of bev particularly in this subgroup. Any real-world study may be limited by the potential presence of selection bias of patients to receive bevacizumab or not. [Table: see text]

Background This study aimed to describe the treatment strategies and outcomes for women with newly diagnosed advanced high-grade serous or endometrioid ovarian cancer (OC). Methods This observational study collected real-world medical record data from eight Western countries on the diagnostic workup, clinical outcomes, and treatment of adult women with newly diagnosed advanced (Stage III-IV) high-grade serous or endometrioid OC. Patients were selected backward in time from April 1, 2018 (the index date), with a target of 120 patients set per country, followed for >= 20 months. Results Of the 1119 women included, 66.9% had Stage III disease, 11.7% had a deleterious BRCA mutation, and 26.6% received bevacizumab; 40.8% and 39.3% underwent primary debulking surgery (PDS) and interval debulking surgery (IDS), respectively. Of the patients who underwent PDS, 55.5% had no visible residual disease (VRD); 63.9% of the IDS patients had no VRD. According to physician-assessed responses (at the first assessment after diagnosis and treatment), 53.2% of the total population had a complete response and 25.7% had a partial response to first-line chemotherapy after surgery. After >= 20 months of follow-up, 32.9% of the patients were disease-free, 46.4% had progressive disease, and 20.6% had died. Bevacizumab use had a significant positive effect on overall survival (hazard ratio [HR], 0.62; 95% CI, 0.42-0.91; p = .01). A deleterious BRCA status had a significant positive effect on progression-free survival (HR, 0.60; 95% CI, 0.41-0.84; p < .01). Conclusions Women with advanced high-grade serous or endometrioid OC have a poor prognosis. Bevacizumab use and a deleterious BRCA status were found to improve survival in this real-world population. Lay summary Patients with advanced (Stage III or IV) ovarian cancer (OC) have a poor prognosis. The standard treatment options of surgery and chemotherapy extend life beyond diagnosis for 5 years or more in only approximately 45% of patients. This study was aimed at describing the standard of care in eight Western countries and estimating how many patients who are diagnosed with high-grade serous or endometrioid OC could potentially be eligible for first-line poly(adenosine diphosphate ribose) polymerase inhibitor (PARPi) maintenance therapy. The results highlight the poor prognosis for these patients and suggest that a significant proportion (79%) would potentially be eligible for first-line PARPi maintenance treatment.

Introduction/Background Recent randomized clinical trials have demonstrated convincing effects of integrating PARP inhibitors (PARPi) and combination of PARPi + bevacizumab (anti-VEGF) into first line (1L) treatment of selected groups of advanced stage ovarian cancer (OC) patients. However, it remains unclear to which extent eligibility of PARPi treatment translates into a real-world setting, where the impact of patient heterogeneity and differences in national clinical practices may influence the potential for PARPi treatment. The aim of this study is to describe treatment strategies and outcomes of advanced OC; and to estimate the proportion of patients potentially eligible for 1L PARPi maintenance therapy and for concomitant anti-VEGF treatment practice using observational data in a multi-national setting (RESPONSE). Methodology This international, multi-centre, observational study, includes real-world data on diagnostic work-up, standard of care, clinical outcomes and treatment for around 1000 patients with advanced OC (≥120 patients/country). Last index date is 1st April 2018, ensuring at least 20 months of follow-up. Potential PARPi eligibility is defined as having no macroscopic residual disease (<1 cm) following upfront surgery and/or having a clinical complete response/partial response (CR/PR) following completion of 1L chemotherapy according to the label. Eligibility for PARPi treatment will be analysed prospectively by time-to-event by individual country, all countries combined, and in relation to treatment patterns. Finally, between-country variations will be described in relation to 1L treatment patterns and national guidelines. Results In total, eight countries, Austria, Belgium, Denmark, Finland, Israel, Netherlands, Norway, and Portugal, are included in the study (study flow chart; figure 1). Data collection is ongoing and will be finalized by Q1 2021. Inclusion of 120 patients per site will provide precise estimates of local PARPi eligibility (error margin of 4%) and sufficient power to detect clinical meaningful differences in PARPi eligibility between any two countries. Conclusion International real-world OC data is currently scarce. RESPONSE will add to the current knowledge regarding factors influencing eligibility to 1L PARPi or PARPi + anti-VEGF maintenance treatment in individual countries, and enable mapping of patient characteristics and key variables in the 1L treatment pathway, such as timing and outcome of surgery, including concomitant anti-VEGF treatment. Disclosures Professor Christian Marth has received funded research from EU, FWF, AstraZeneca and Roche, Honoraria/Expenses from Roche, Novartis, Amgen, MSD, Pharmamar, AstraZeneca, and Tesaro, and has performed Consulting/Advisory Boards for Roche, Novartis, Amgen, MSD, AstraZeneca, Pfizer, Pharmamar, Cerulean, Vertex, and Tesaro. Dr Jacob Korach has nothing to disclose. Dr Kristina Lindemann has acted as Consultant for AstraZeneca, Speaker for AstraZeneca and GSK, and participated in Advisory Boards for AstraZeneca and GSK. Dr Anne Weng Ekmann-Gade has received research grants for the current trial Dr E Van Nieuwenhuysen has nothing to disclose. Dr Heini Lassus has nothing to disclose. Dr Klaus Kaae Andersen is employed by AstraZeneca. Jesper Hansen is employed by AstraZeneca.