In a nutshell
The authors compared the effectiveness and safety of SB2, a biological variant of infliximab (Remicade) — the original biological product, to infliximab itself in patients with moderate to severe rheumatoid arthritis (RA).
Some background
In RA, high levels of immune system protein are generated which causes inflammation, leading to chronic pain. Methotrexate (Trexall) is one of the most commonly used drugs in the treatment of RA. However, many RA patients fail to respond to methotrexate. Infliximab is an alternative treatment approved for RA. It blocks specific parts of the immune system that play a key role in RA inflammation. SB2 is a biosimilar of infliximab. A biosimilar is a biological product, which is highly similar to an already approved biological product (reference product –infliximab, in this case) in terms of safety and function. In early clinical studies, SB2 showed comparable effectiveness to that of infliximab.
A large population based study is needed to establish the benefit of SB2 in moderate to severe RA.
Methods & findings
The authors aimed to compare the effectiveness of SB2 to infliximab in patients with moderate to severe RA.
584 patients were included in this phase III study. All patients had moderate to severe RA despite treatment with methotrexate. 291 patients received SB2 (group1). 293 patients received infliximab (group 2). The median (midpoint) follow-up was 296 days. Patients were evaluated for ACR 20/50/70 response, (DAS) 28 and safety after 30 weeks of treatment.
ACR 20/50/70 (American College of Rheumatology) response measures 20%, 50% or 70% improvements in swollen or tender joints after treatment. DAS (disease activity score) 28 is an assessment to measure the progress and improvement of RA by examining 28 joints.
The ACR 20 response at week 30 was 64.1% in group 1 compared to 66% in group 2. The ACR 50/70 response and DAS 28 score were similar between group 1 and group 2. Treatment-related side effects occurred in 57.6% of patients in group 1. This was compared to 58% in group 2. Immunogenicity (using a substance to start an immune response) of SB2 and infliximab was measured. 55.1% of patients in group 1 and 49.7% of patients in group 2 experienced an immunogenic response.
The bottom line
The authors concluded that the safety and effectiveness of SB2 were similar to infliximab in the treatment of moderate to severe RA.
Published By :
Annals of the rheumatic diseases
Date :
Aug 28, 2015
