Extended induction in the True North OLE study: ozanimod efficacy in biologic-naive and biologicexperienced patients

Abstract Background Prior exposure to biologics can influence response to subsequent lines of advanced therapies. Previous analyses showed that patients who did not achieve clinical response following 10 weeks of ozanimod treatment in the phase 3 True North (TN) study benefited from extended induction with open-label ozanimod in the TN open-label extension (OLE) study. As the impact of prior biologic exposure on outcomes with extended induction is unknown, the aim of this analysis was to evaluate that question. Methods Clinical nonresponders to ozanimod at TN Week (W) 10 entered the OLE (data cutoff: January 10, 2022, at which point the disposition was available until OLE W94 for all patients). Data were analysed in patients with and without prior biologic exposure at baseline. Disease activity was assessed at TN W0 (baseline) and at W10 (OLE entry). Symptomatic clinical response and remission were evaluated through OLE W94, and multiple clinical, endoscopic, and histologic endpoints were evaluated at OLE W46 and W94 using observed case (OC) and nonresponder imputation (NRI) analyses. Results A total of 220 patients with prior biologic information entered the OLE after not achieving clinical response at TN W10 (biologic-naive, n=122; biologic-experienced, n=98). Disease activity at baseline was generally consistent between biologic-naive and experienced patients. About half of the ozanimod W10 nonresponders in both groups achieved symptomatic clinical response by OLE W5, with a higher proportion of biologic-naive patients maintaining response until OLE W94 in both OC and NRI analyses (Figure 1). Higher proportions of biologic-naive patients also sustained symptomatic clinical remission until OLE W94 in both OC and NRI analyses. In OC analysis, a higher proportion of biologic-naive patients achieved all clinical, endoscopic, and histologic endpoints at OLE W46 compared with biologic-experienced patients; by OLE W94, however, the proportions of patients who achieved all clinical, endoscopic, and histologic endpoints were generally consistent, regardless of prior biologic exposure (Figure 2). As expected, a smaller proportion of patients achieved the efficacy endpoints in the NRI analysis, with proportions being higher in biologic-naive patients; response rates were sustained between OLE W46 and W94 in each group. Conclusion Both biologic-naive and -experienced clinical nonresponders to ozanimod at the end of induction demonstrated response to extended induction with ozanimod. Delayed response was durable for up to 2 years of continuous ozanimod treatment in both groups, with higher proportions achieved in biologic-naive patients.