This pivotal phase 2 study evaluated the safety and efficacy of brentuximab vedotin in patients with relapsed or refractory (R/R) systemic anaplastic large cell lymphoma (ALCL). After a median observation period of approximately 6 years from first treatment, we examined the durability of remission, progression-free survival (PFS), overall survival (OS), and safety outcomes of patients treated on this trial. Among all enrolled patients (n558), no progressions were observed beyond 40months, and median OS was not reached. Patients with a complete response (CR), as assessed by the investigator (38 of 58, 66%), continued to demonstrate improved outcomes with neither median OS nor PFS reached. Of the 38 CR patients, 16 received a consolidative stem cell transplant (SCT) with median PFS not reached. Among patients who were on-study and in remission at study closure, 16 patients had not received any new treatment after single-Agent brentuximab vedotin other than consolidative SCT. Among this subset of 16 patients, 8 received SCT, and the remaining 8 patients(14% of all enrolledpatients)remained in sustained remissionwithoutconsolidative SCT or any new anticancer therapy. Thirty-Three patients experienced peripheral neuropathy, among whom, the majority (30 of 33, 91%) had experienced resolution or improvement at their last assessment. These final results, which demonstrated a high rate of peripheral neuropathy resolution, and durable remissions in a subset of patients with relapsed or refractory systemic ALCL, provide evidence that single-Agent brentuximab vedotin may be a potentially curative treatment option.