Efficacy and safety of switching from reference adalimumab to CT-P17 (100 mg/ml): 52-week randomized, double-blind study in rheumatoid arthritis.

OBJECTIVE: To compare the safety and efficacy of switching from reference adalimumab to adalimumab biosimilar CT-P17 with continuing reference adalimumab/CT-P17 in active RA. METHODS: This double-blind, phase III study randomized (1:1) subjects with active RA to receive 40 mg (100 mg/ml) CT-P17 or European Union-sourced reference adalimumab subcutaneously every 2 weeks (Q2W) until week (W) 24 [treatment period (TP) 1]. Thereafter, subjects receiving reference adalimumab were randomized (1:1) to continue reference adalimumab or switch to CT-P17 from W26 (both Q2W until W48; TP2). Subjects receiving CT-P17 in TP1 continued CT-P17. W0-W24 results were previously reported; we present W26-W52 findings. End points were efficacy (including joint damage progression), pharmacokinetics, safety and immunogenicity. RESULTS: Of 607 subjects who initiated TP2 treatment, 303 continued CT-P17, 153 continued reference adalimumab and 151 switched to CT-P17. Efficacy improvements up to W24 were maintained during TP2; efficacy was comparable among groups. At W52, 20% improvement in ACR response rates were 80.5% (continued CT-P17), 77.8% (continued reference adalimumab) and 82.2% (switched to CT-P17). Joint damage progression was minimal. Mean trough serum adalimumab concentrations were similar among groups. CT-P17 and reference adalimumab safety profiles were numerically similar and switching did not affect immunogenicity. At W52, 28.4% (continued CT-P17), 27.0% (continued reference adalimumab) and 28.3% (switched to CT-P17) of subjects were anti-drug antibody-positive. CONCLUSION: Efficacy, pharmacokinetics, safety and immunogenicity of CT-P17 and reference adalimumab were comparable after 1 year of treatment, including after switching from reference adalimumab to CT-P17. TRIAL REGISTRATION: ClinicalTrials.gov, http://clinicaltrials.gov, NCT03789292.

Efficacy and safety of biosimilar CT-P17 versus reference adalimumab in subjects with rheumatoid arthritis: 24-week results from a randomized study.

BACKGROUND: To demonstrate equivalent efficacy of the proposed high-concentration (100 mg/ml), citrate-free adalimumab biosimilar CT-P17 to European Union-approved adalimumab (EU-adalimumab) in subjects with active rheumatoid arthritis (RA). METHODS: This randomized, double-blind phase III study ( ClinicalTrials.gov , NCT03789292) randomized (1:1) subjects with active RA at 52 centers to receive CT-P17 or EU-adalimumab 40 mg subcutaneously every 2 weeks until week 52. Results to week 24 are reported here. The primary endpoint was 20% improvement by American College of Rheumatology criteria (ACR20) response rate at week 24. Equivalence was concluded if the corresponding confidence intervals (CIs) for the estimate of treatment difference were within predefined equivalence margins: - 15 to 15% (95% CI; European Medicines Agency assumption); - 12 to 15% (90% CI; Food and Drug Administration assumption). Additional efficacy, pharmacokinetic, usability, safety, and immunogenicity endpoints were evaluated. RESULTS: 648 subjects were randomized (324 CT-P17; 324 EU-adalimumab). The ACR20 response rate at week 24 was 82.7% (n = 268/324) in both groups (intention-to-treat population). The 95% CI (- 5.94 to 5.94) and 90% CI (- 4.98 to 4.98) were within predefined equivalence margins for both assumptions and equivalent efficacy was concluded. Additional endpoints and overall safety were comparable between groups. Mean trough serum concentrations of CT-P17 were slightly higher than those of EU-adalimumab. Immunogenicity was slightly lower numerically for the CT-P17 group than for the EU-adalimumab group. CONCLUSIONS: CT-P17 and EU-adalimumab have equivalent efficacy and comparable safety and immunogenicity in subjects with active RA. Overall safety of CT-P17 is consistent with the known safety profile of reference adalimumab. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03789292 . Registered 28 December 2018-retrospectively registered.