Subgroup analysis of older patients treated within the randomized phase 3 doxorubicin versus doxorubicin plus evofosfamide (SARC021) trial

Background: More than half of patients with soft tissue sarcoma (STS) are aged ≥65 years (older), however contemporary data on the efficacy/safety of anthracycline chemotherapy in older patients with STS are lacking. Methods: SARC021 randomized patients to receive first-line doxorubicin or doxorubicin plus evofosfamide. The main aim of this study was to compare the outcome and safety of first-line anthracycline-based therapy in older patients compared with those <65 years. IRB approval was obtained at all participating sites and this research meets requirements for protection of human subjects. Results: Of 640 patients, 209 (33%) were older, with a median age 70 (range 65–89) years. The median overall survival (OS) was 16.7 months (95%CI: 13.2–20.0) in older patients compared to 20.1 months (95%CI: 16.9–23.2) in those aged <65 years (n = 431), HR 1.21 (95%CI: 0.99–1.48), p = .057. The median progression-free survival (PFS) in older patients was 6.3 months (95%CI: 5.8–7.2) compared to 6.0 (95%CI: 5.1–6.4) in those <65 years, HR 0.86 (95%CI: 0.70–1.05), p = .14. Older patients had significantly more hematological (141 [67%] versus 208 [48%], p < .0001), non-hematological (131 [63%] versus 215 [50%], p = .0097) and ≥ Grade 3 adverse events (178 [85%] versus 299 [69%], p = .0002), compared to younger patients. More older patients (30, 14%) stopped treatment due to adverse events compared to younger patients (22, 5%), p = .0001. Conclusions: The efficacy of first-line anthracycline-based chemotherapy did not differ significantly between older and younger advanced sarcoma patients. Significantly more older patients stopped chemotherapy due to adverse events. These results provide a benchmark for daily clinical practice and future trials in older patients.