Emery P, et al. – The 52–week efficacy and safety of SB4 [an etanercept biosimilar] were compared with reference etanercept (ETN) in patients with active rheumatoid arthritis (RA). In investigations, the efficacy including radiographic progression was comparable between SB4 and ETN up to week 52. SB4 was well tolerated and had a similar safety profile to that of ETN.

Methods

• In this study, patients with moderate to severe RA despite MTX treatment were randomized to receive 50 mg/week of s.c. SB4 or ETN up to week 52.
• ACR response rates, 28–joint DAS, Simplified and Clinical Disease Activity Indices and changes in the modified total Sharp score (mTSS) were included in the efficacy assessments.
• Safety and immunogenicity were also analyzed.

Results

• 596 patients were randomized to receive either SB4 (n = 299) or ETN (n = 297).
• 505 (84.7%) patients completed 52 weeks of the study.
• The ACR20 response rates in the per–protocol set were comparable between SB4 (80.8%) and ETN (81.5%), at week 52. 
• Between the two groups, all efficacy results were comparable and they were maintained up to week 52.
• Radiographic progression was also comparable and the change from baseline in the mTSS was 0.45 for SB4 and 0.74 for ETN. 
• The safety profile of SB4 was similar to that of ETN and the incidence of anti–drug antibody development up to week 52 was 1.0 and 13.2% in the SB4 and ETN groups, respectively.