OBJECTIVEThe primary objective is to describe the real-life effectiveness and safety of nivolumab treatment in patients with relapsed or refractory classical Hodgkin's lymphoma. The secondary objective is to describe the therapeutic management after nivolumab monotherapy.METHODObservational, retrospective, multidisciplinary study including all patients with relapsed or refractory classical Hodgkin's lymphoma treated with nivolumab monotherapy from November 2015 to March 2023. Patient and treatment-related variables were collected. Effectiveness was measured as overall response rate, progression-free survival, and overall survival. Safety was measured as percentage of patients with adverse effects and severity.RESULTSThirteen patients were included, median age 37.5 years (RIQ: 25.3-54.7), 84.6% male. The median number of previous lines of therapy was 3 (RIQ: 2-4.5), including autologous haematopoietic stem cell transplantation (84.6%) and brentuximab vedotin (100%). All received nivolumab 3 mg/kg/14 days, with a median of 11 cycles (RIQ: 6.5-20.5) per patient. Median time on treatment was 4.9 months (RIQ: 3-9.6) and median follow-up time was 9.2 months (RIQ: 5.6-32.3). Complete response was achieved by 3 patients (23.1%), partial response by 3 (23.1%), stable disease by 3 (23.1%), and progression by 4 (30.8%). The objective response rate was 46.2%. Median progression-free survival was 23.9 months (95% CI: 0-49.1), median overall survival was not reached. At the study cut-off date, 5 patients had died (38.5%), 4 were in complete remission without active treatment (30.8%), and 4 were continuing treatment (30.8%). Adverse events occurred in 76.9% of patients, 44% of severity ≥3, the most frequent being hypothyroidism and hepatotoxicity. One patient discontinued treatment due to pneumonitis, 2 suffered treatment delays (thrombocytopenia and hypertransaminemia), and 1 changed the regimen to monthly (pulmonary toxicity).CONCLUSIONSNivolumab in the treatment of relapsed or refractory classical Hodgkin's lymphoma has confirmed favourable effectiveness data in the study sample, expressed as objective response rate of 46.2% and a clinical benefit rate of 69.2%. Safety was acceptable, manageable, and consistent with that described in the literature.