Progression-free survival may be a better primary outcome in trials on re-lapsed/refractory Ewing sarcoma

Progression-free survival (PFS) may be a better primary outcome for clinical trials on re-lapsed/refractory Ewing sarcoma (RR-ES) since response does not correlate with survival outcomes in this population, according to data presented at the 2020 American Society of Clinical Oncology (ASCO) Virtual Scientific Program.

In this study, data from 241 patients with RR-ES who were evaluable for imaging response were randomized to receive either topotecan-cyclophosphamide, irinotecan-temozolomide, gemcitabine-docetaxel (GD), or high-dose ifosfamide.

Progression-free survival and overall survival were similar for patients with partial response or complete response/partial response compared to those with stable disease. For patients with progressive disease, overall survival was inferior.

The authors concluded response does not correlate with survival outcomes in RR-ES and using partial or complete response as a marker of success and stable disease as a marker of failure may be misleading. Progression free survival is a potentially better primary outcome for clinical trials in RR-ES, the researchers concluded.

Reference

Wheatley K, et al. Correlation of response with progression-free (PFS) and overall (OS) survival in relapsed/refractory Ewing sarcoma (RR-ES): Results from the rEECur trial. Presented at: the 2020 American Society of Clinical Oncology (ASCO) Virtual Scientific Program.