Abstract 26P
Background
There is limited evidence of RW outcomes for pts with A/R EC. This descriptive, noninterventional, retrospective study reports RW pt characteristics and survival outcomes in a cohort of pts with A/R EC in England who received first-line (1L) therapy and could have been eligible for a clinical trial of an immune checkpoint inhibitor (ICI) in EC.
Methods
This study used routine population-level data, available through the National Disease Registration Service in England. Pts diagnosed with A/R EC (recurrences identified via a defined algorithm) between 1 Jan 2013 and 31 Dec 2019 were included (follow-up until 23 Aug 2021). Patients in the ICI cohort had received any 1L therapy for A/R EC and met the key eligibility criteria of the RUBY trial (A Study to Evaluate Dostarlimab Plus Carboplatin-paclitaxel Versus Placebo Plus Carboplatin-paclitaxel in Participants With Recurrent or Primary Advanced Endometrial Cancer; NCT03981796). Demographics, baseline characteristics, and therapy received were reported. Overall survival (OS), time to next treatment (TTNT; a proxy for progression-free survival), and time to treatment discontinuation (TTD) from 1L chemotherapy initiation (index date) were assessed using Kaplan-Meier methodology.
Results
Of 9629 identified pts with A/R EC who received any 1L therapy, 24.7% (N=2376) were in the ICI cohort (demographics in table). Median TTNT, median TTD, and median OS in months from 1L chemotherapy initiation were 16.9 (95% confidence interval [CI]: 15.8–18.5), 3.4 (95% CI: 3.4–3.4), and 27.2 (95% CI: 24.7–30.2), respectively. Table: 26P
| Characteristic | N=2376 |
| Median age, years (range) | 67.9 (26.7–94.0) |
| Disease stage at primary diagnosis, n (%) | |
| FIGO I/II | 401 (16.9) |
| FIGO III/IV | 1975 (83.1) |
| Histology, n (%) | |
| Endometrioid | 1049 (44.1) |
| Serous | 667 (28.1) |
| Carcinosarcoma | 309 (13.0) |
| Nonspecific carcinoma | 105 (4.4) |
| Clear cell carcinoma | 103 (4.3) |
| Other | 143 (6.0) |
| 1L systemic anticancer therapy received, n (%) | |
| Carboplatin+paclitaxel | 1824 (77.8) |
| Carboplatin | 302 (12.9) |
| Cisplatin | 49 (2.1) |
| Doxorubicin | 16 (0.7) |
| Other | 154 (6.6) |
| None | 31 (1.3) |
Conclusions
This RW study in England demonstrates that 1L survival outcomes are poor for pts with A/R EC who received 1L therapy, highlighting the critical unmet need for more effective therapies to delay EC relapse and prolong pt survival.
Clinical trial identification
OneCDP218291.
Editorial acknowledgement
Editorial support provided by Hayley Butler, PhD, of Fishawack Health, funded by GSK.
Legal entity responsible for the study
GSK.
Funding
Study funded by GSK (OneCDP218291).
Disclosure
K. Heffernan: Financial Interests, Personal, Other, Employee: GSK. J. Garside: Financial Interests, Personal, Other, Employee: GSK. T. Rahman: Other, Personal, Other, Data Scientist: Health Data Insight CIC. C. Pearson: Other, Personal, Other, Senior Health Data Analyst: Health Data Insight CIC. S. Banerjee: Financial Interests, Personal, Other, Employee: GSK; Financial Interests, Institutional, Other, Research grants: AstraZeneca, GSK; Financial Interests, Personal, Other, Advisory boards: Amgen, AstraZeneca, Epsilogen, GSK, Immunogen, Merck Sharpe Dohme, Merck Sereno, Mersana, Novartis, Oncxerna, Regeneron, Seagen, Shattuck Labs; Financial Interests, Personal, Other, Honoraria for lectures: Amgen, AstraZeneca, Clovis, GSK, Immunogen, Merck Sharpe Dohme, Mersana, Pfizer, Roche, Takeda. All other authors have declared no conflicts of interest.