Switching From Reference Adalimumab to SB5 (Adalimumab Biosimilar) in Patients With Rheumatoid Arthritis:...

Area of Science:

• Rheumatology
• Immunology
• Pharmacology

Background:

• Previous studies demonstrated comparable 24-week efficacy and safety of biosimilar SB5 and reference adalimumab (ADA) in moderate-to-severe rheumatoid arthritis (RA).
• A transition study was designed to further assess patients switching from ADA to SB5 or continuing on either treatment up to 52 weeks.

Purpose of the Study:

• To evaluate the long-term efficacy, safety, and immunogenicity of biosimilar SB5 compared to reference adalimumab (ADA) in patients with moderate-to-severe rheumatoid arthritis (RA).
• To assess the impact of switching from ADA to SB5 on treatment outcomes up to 52 weeks.

Main Methods:

• A phase III, randomized, 52-week study involving patients with moderate-to-severe RA.
• Patients were initially randomized to SB5 or ADA (40 mg subcutaneously every other week).
• At 24 weeks, ADA patients were rerandomized to continue ADA or switch to SB5; SB5 patients continued SB5.

Main Results:

• Efficacy, safety, and immunogenicity were comparable across all treatment groups up to 52 weeks.
• American College of Rheumatology (ACR) response rates (ACR20/50/70) were maintained after switching from ADA to SB5 and were comparable across groups (ACR20: 73.4%-78.8% at week 52).
• Minimal and comparable radiographic progression was observed; safety profiles and antidrug antibody incidence were similar post-transition.

Conclusions:

• Biosimilar SB5 demonstrated well-tolerated, comparable efficacy, safety, and immunogenicity to reference adalimumab (ADA) over one year in RA patients.
• Switching from ADA to SB5 did not result in emergent safety issues, increased immunogenicity, or loss of efficacy.