Background: Nivolumab (nivo), a fully human IgG4 immune checkpoint inhibitor targeting PD-1, showed encouraging efficacy in relapsed/refractory cHL in a ph1 study (Ansell et al. NEJM 2014). Cohort B of CheckMate 205 ph2 study investigated nivo in cHL pts who had failed autologous hematopoietic stem cell transplantation (auto-HSCT) and brentuximab vedotin (BV): ORR per independent radiologic review committee was 66% and 6-m PFS was 77% (Engert et al. EHA 2016; abstr S793). Due to limited treatments there is a need to provide durable efficacy while maintaining/improving QoL. Aim: Evaluate QoL in pts receiving nivo in CheckMate 205 cohort B. Methods: This ongoing ph2 study (NCT02181738) assessed QoL in cHL pts receiving nivo 3 mg/kg IV q2w. Pt-reported QoL was assessed using European Organization for Research and Treatment of Cancer Quality of Life Questionnaire – Core 30 (EORTC QLQ-C30) and EuroQol Five Dimensions Questionnaire (EQ-5D) q4 cycles on treatment. EQ-5D visual analog scale (VAS) scores range 0–100 and EQ-5D utility index scores –0.6–1 (higher scores=better health state). A 7- and 0.08-point change from baseline (BL) in VAS and utility index score, respectively, represent a clinically meaningful improvement (CMI). QLQ-C30 scores range 0–100 (high scores=higher level of function/global health status [GHS]; for symptom scales, higher level of symptom burden); 10-point change represents a CMI. Changes from BL estimates are based on a mixed model with time point as a fixed effect. Missing data was investigated to assess possible bias. Results: BL and subsequent QoL assessment was completed by 72 treated pts (90%) from cohort B (n=80). Most pts with an on-treatment study visit through wk33 (n=47/72) completed both questionnaires (n=42). CMI in mean EQ-5D VAS scores were maintained over time on treatment (VAS mean change BL–wk33: 19.6, p≤0.001). Changes of the utility index least squares were significant (p≤0.005) at all treatment time points. For the QLQ-C30, significant improvements from baseline were observed from wk9 for: fatigue, dysnpena, appetite loss, physical function, role function and global health status. No QoL scale indicated deterioration during treatment. Conclusion: In cHL pts who had failed auto-HSCT and BV, nivo resulted in a trend towards QoL improvement in this small cohort. An improvement in GHS (EQ-5D VAS) was observed by wk9 and maintained over time on treatment. Funding: BMS. Medical writing: S Addison, Caudex, funded by BMS