Real-world evidence of overall survival (OS) and treatment patterns of patients (pts) with testicular germ cell tumors (GCT) receiving palliative chemotherapy in the United States.

5038 Background: Pts with relapsed/refractory (R/R) GCT have a poor prognosis, with only palliative options remaining. Real-world data in this population, particularly around prior salvage strategies with high-dose (HDCT) or conventional-dose chemotherapy (CDCT), are needed to inform future treatment standards. Methods: Adult males with R/R testicular GCT who received palliative chemotherapy between 01/2016 to 03/2023 were identified in the Komodo Research Database Demographics were described on the index date, defined as the date of palliative chemotherapy initiation. OS, defined as the time from index date to death and stratified by prior HDCT exposure, was assessed among pts with 12 months (mos) follow-up time using the Kaplan-Meier method. Additionally, treatment patterns were analyzed in a subgroup of pts with an eligible health plan continuously from diagnosis to index date. Results: Of 57,508 pts with testicular GCT, 248 received palliative chemotherapy, among whom 97 (39.1%) had sufficient claims data to confirm prior exposure to salvage HDCT (+/- CDCT) or only CDCT (57 HDCT; 40 CDCT only). Median (interquartile range IQR) age on the index date for these 97 pts was 32 (25-42) years and most had commercial (47.4%) or Medicaid (36.1%) insurance. Observed index palliative regimens included gemcitabine + oxaliplatin (46.4%), oral etoposide (12.4%), and gemcitabine + paclitaxel (12.4%); 24.7% of pts received multiple palliative regimens (median 2, range 2-5). Median (95% confidence interval) OS was 8.0 (6.3-9.7) mos; 7.0 (5.7-9.7) mos for those HDCT exposed, and 9.3 (7.5-22.6) mos for those exposed to CDCT only. The treatment patterns subgroup comprised 51 pts observed for a median of 19.9 (IQR: 15.6-28.8) mos after diagnosis. Median (IQR) time from diagnosis to first-line (1L) chemotherapy was 0.9 (0.5-2.1) mos and to palliative chemotherapy was 12.5 (9.0-16.8) mos. Prior to palliative chemotherapy, 33 pts (64.7%) received salvage chemotherapy, including HDCT (+/- CDCT) in 23 pts (69.7%) and only CDCT in 10 pts (30.3%). Of 18 pts (35.3%) who did not receive salvage chemotherapy prior to palliative chemotherapy, median time from end of 1L chemotherapy to index date was 4.1 (IQR: 2.4-8.0) mos and 13 pts (72.2%) had renal insufficiency. Conclusions: Real-world data was able to capture treatment patterns, palliative chemotherapy use, and outcomes for pts with R/R testicular GCT. Surprisingly, more than 1/3 of pts did not receive a salvage chemotherapy regimen prior to palliative chemotherapy and of those who did, >30% did not receive HDCT. Renal insufficiency may be a major reason for lack of salvage chemotherapy use. These data provide prognostic information and variables influencing poor outcome in this understudied population for whom novel treatments are urgently needed.