Multicenter phase 2 trial of second-line avelumab plus gemcitabine for advanced leiomyosarcoma

The multicenter phase 2 EAGLES study in South Korea evaluated avelumab (anti-PD-L1) plus gemcitabine for patients with advanced leiomyosarcoma (aLMS) who failed on first-line chemotherapy. Among 35 evaluable patients, one had complete response and six had partial response, for an ORR 20% (95% CI 8-37), while 18 additional patients had stable disease, for a DCR of 71% (54-85). The median duration of response was 21.8 months (range 7.6 - ≥43.3). The median progression-free survival and overall survival were 5.6 months (95% CI 4.5-6.8) and 27.5 months (20.4-34.6), respectively. Grade 3 or 4 adverse events occurred in 70% of patients, and immune-related adverse events occurred in 14%. Patients with higher density of tumor-infiltrating lymphocytes (greater than the median) had better ORR, PFS, and OS. The authors conclude that the combination of avelumab and gemcitabine demonstrated promising efficacy and manageable safety among aLMS patients who progressed on first-line chemotherapy.