Background SB4 is approved by the European Medicines Agency as a biosimilar of the etanercept reference product (ETN). The phase I clinical study results and 52-week results of phase III clinical study have been reported previously.1–3
Objectives To evaluate the long term safety, immunogenicity, and efficacy of continuing SB4 vs. switching (as will occur in clinical practice) from ETN to SB4 in patients with moderate to severe RA.
Methods The phase III randomised, double-blind study period consisted of 52 weeks of treatment with either weekly dose of subcutaneous 50 mg SB4 or ETN with background methotrexate (MTX) in patients with moderate to severe RA. After 52 weeks of treatment, patients in Czech Republic and Poland were enrolled into the open-label, extension period and received SB4 for additional 48 weeks. Efficacy, safety, and immunogenicity were assessed up to Week 100.
Results At Week 52, 245 patients from the randomised, double-blind study period enrolled into the extension study: 126 patients continued to receive SB4 (SB4/SB4) and 119 patients switched from ETN to SB4 (ETN/SB4). Among them, 119 (94.4%) patients of SB4/SB4 and 113 (95.0%) patients of ETN/SB4 completed 100 weeks of treatment. SB4 was well tolerated and the safety profile was comparable between SB4/SB4 and ETN/SB4 during the open-label, extension period (Table 1). Adverse events were those newly occurring after Week 52 in 47.6% of SB4/SB4 and 48.7% of ETN/SB4. There were no cases of injection site reactions reported after Week 52. The overall incidence of anti-drug antibodies after Week 52 was 0.8% in SB4/SB4 and 0.9% in ETN/SB4. Efficacy was sustained and comparable between SB4/SB4 and ETN/SB4 up to Week 100 (Table 2).
Conclusions SB4 was well tolerated and effective over 2 years in patients with RA. Efficacy, safety, and immunogenicity were comparable between the SB4/SB4 and ETN/SB4, demonstrating that switching produced no treatment emergent issues such as loss of efficacy, increase in adverse events, or increase in immunogenicity.
Lee YJ et al. Ann Rheum Dis. 2015; 74 (Suppl2: 718), SAT0176
Emery P et al. Ann Rheum Dis. 2015–207588 [Epub ahead of print]
Vencovsky J et al. Arthritis Rheumatol. 2015; 67 (suppl 10), 2055
Disclosure of Interest P. Emery Consultant for: Samsung Bioepis, AbbVie, Pfizer, Merck, UCB, BMS, Sandoz, J. Vencovský Consultant for: Pfizer, servier, Samsung Bioepis, Eli Lilly, BMS, Novarti, Speakers bureau: UCB, Pfizer, AbbVie, MSD, A. Sylwestrzak Grant/research support from: Samsung Bioepis, P. Leszczyński Grant/research support from: Samsung Bioepis, W. Porawska Grant/research support from: Samsung Bioepis, B. Stasiuk Grant/research support from: Samsung Bioepis, J. Hilt Grant/research support from: Samsung Bioepis, Z. Mosterova Grant/research support from: Samsung Bioepis, S. Y. Cheong Employee of: Samsung Bioepis, J. Ghil Employee of: Samsung Bioepis