e18017 Background: The CheckMate-141 trial led to the approval of nivolumab in platinum-resistant metastatic squamous cell carcinomas of the head and neck (SCCHN). We evaluated outcomes of SCCHN patients in Ontario, Canada treated with nivolumab since its funding through the New Drug Funding Program (NDFP) of Cancer Care Ontario (CCO). Methods: Retrospective review using the provincial treatment registry (CCO NDFP) was undertaken. Patient characteristics, reason for treatment, treatment length, and date of death were collected. Kaplan-Meier method was used to estimate overall survival and Cox regression to evaluate prognostic effect of selected factors. Results: 134 patients with SCCHN received nivolumab between March 2017 and March 2019. Median patient age was 63 years with 80.6% male. Nivolumab was used as second-line therapy after disease relapse within 6 months of curative-intent platinum chemotherapy (PC) in 39.6% of patients (Indication 1 – I1), used as second-line therapy post PC in non-curative intent in 42.6% of patients (Indication 2 – I2), and used as first-line therapy in non-curative intent due to contraindication for PC in 17.2% of patients (Indication 3 – I3). Median overall survival (mOS) was 5.8 months (95% confidence intervals (CI) 4.5-7.3), and one-year OS was 28.4% (CI 2.10-36.1). HPV status had no statistically significant impact on OS (p = 0.12). Patients with a lower BSA (< 1.81) had median OS of 3.9 months (CI 3.1-6.7) versus 9.0 months (CI 6.5-14.8) in those with higher BSA, HR = 0.12 (CI 0.04-0.39, p < 0.001). Differences between indications was statistically significant (p < 0.001). Patients who received nivolumab for I1 had mOS 7.2 months (CI 3.8-9.8) versus 11.9 months (CI 6.2-not reached) for I3, HR = 1.73(CI 0.94-3.16). Patients who received nivolumab for I2 had mOS 3.9 months (CI 2.9-5.4) as compared to I3, HR = 3.27(CI 1.80-5.94). Patients who received nivolumab for I2 had poorer mOS as compared to I1 HR = 1.90(CI 1.23-2.92). Conclusions: Real world data in Ontario demonstrates poorer mOS, but similar 1-year survival compared to CheckMate-141 trial. HPV status had no significant impact on mOS. Patients who received nivolumab as first-line therapy in the non-curative setting appeared to have longer mOS than those who received initial PC for non-curative intent followed by nivolumab. Patients who received nivolumab as second-line therapy post PC in non-curative intent setting as compared to within 6 months of curative-intent therapy had poorer mOS.