Biosimilar Candidate CT-P42 in Diabetic Macular Edema: 24-Week Results from a Randomized, Active-Controlled, Phase III Study

Abstract

ObjectiveTo demonstrate the therapeutic similarity of CT-P42 compared to reference aflibercept (Eylea®) in adult patients with diabetic macular edema (DME). DesignRandomized, active-controlled, double-masked, Phase III clinical trial ParticipantsPatients with a diagnosis of either type 1 or 2 diabetes mellitus (DM) with DME involving the center of the macula. MethodsPatients were randomized (1:1) to receive either CT-P42 or reference aflibercept (2 mg/0.05 mL) by intravitreal injection every 4 weeks (5 doses) then every 8 weeks (4 doses) in the main study period. Results up to Week 24 are reported herein. Main Outcome MeasuresThe primary endpoint was mean change from baseline at Week 8 in best corrected visual acuity (BCVA) using the Early Treatment Diabetic Retinopathy Study (ETDRS) chart. Equivalence between CT-P42 and reference aflibercept was to be concluded if the two-sided 95% confidence interval (CI) (global assumptions) and two-sided 90% CI (US Food and Drug Administration [FDA] assumptions) for the treatment difference fell entirely within the equivalence margin of ±3 letters, as assessed in the full analysis set. ResultsOverall, 348 patients were randomized (CT-P42: 173; reference aflibercept: 175). BCVA improved from baseline to Week 8 in both groups, with a least squares mean (standard error) improvement of 9.43 (0.798) and 8.85 (0.775) letters in the CT-P42 and reference aflibercept groups, respectively. The estimated between-group treatment difference was 0.58 letters, with the CIs within the pre-defined equivalence margin of ±3 letters (95% CI −0.73, 1.88 [global]; 90% CI −0.52, 1.67 [FDA]). Through Week 24, other efficacy results for the two groups, in terms of change in BCVA and retinal central subfield thickness, as well as ETDRS Diabetic Retinopathy Severity Scale score, supported therapeutic similarity. Pharmacokinetics, usability, safety (including the proportions of patients experiencing at least one treatment-emergent adverse event [CT-P42: 50.3%; reference aflibercept: 53.7%]), and immunogenicity were also comparable between groups. ConclusionsThis study in patients with DME demonstrated equivalence between CT-P42 and reference aflibercept (2 mg/0.05 mL) in terms of efficacy, with similar pharmacokinetic, usability, safety, and immunogenicity profiles.