Tocilizumab is a humanised IgG1 monoclonal antibody that prevents interleukin-6 [IL-6] from binding to the IL-6 receptor.1 It is the first licensed biological agent to inhibit IL-6, a major cytokine in the inflammatory network.
In a randomised double-blind trial involving 622 patients with moderate to severe active rheumatoid arthritis with an inadequate response to MTX, significantly more patients receiving tocilizumab 8mg/kg (n=205) or 4mg/kg† (n=213) (given every four weeks with weekly MTX) had an ACR20* response by week 24 than those receiving placebo (n=204) (59 per cent and 48 per cent, respectively vs 26 per cent).2
In the same trial the disease activity score using 28 joint counts (DAS28) decreased rapidly in the tocilizumab groups with DAS28 remission (<2.6) at week 24 achieved in significantly more patients in the tocilizumab 8mg/kg and 4mg/kg† groups than in the placebo group (27 per cent and 13 per cent vs 0.8 per cent).2
Similar results were observed in another trial involving 499 patients with moderate to severe active rheumatoid arthritis and failure to respond, or intolerance to one or more TNF antagonists within the previous year.3 In this trial significantly more patients receiving tocilizumab 8mg/kg or 4mg/kg† (in combination with MTX) achieved an ACR20 response by week 24 compared with those receiving placebo (50.0 per cent and 30.4 per cent vs 10.1 per cent) and significantly more achieved DAS28 remission at week 24 (30.1 per cent and 7.6 per cent vs 1.6 per cent).
The proportion of patients who achieved an ACR70 response was significantly increased in the tocilizumab 8mg/kg groups in both studies.2,3
Tocilizumab has also been shown to produce significant improvements in fatigue (FACIT-fatigue) and quality of life (SF-36 physical and mental) scores at both doses† compared with placebo.2
In the trials most adverse events were mild to moderate occurring with a similar overall incidence in all groups.3 The incidence of serious adverse events was comparable across all groups.2,3
- RoActemra Summary of Product Characteristics, 2009.
- Smolen JS et al. Lancet 2008; 371:987-97.
- Emery P et al. Ann Rheum Dis 2008; 67:1516-23.
† 4mg/kg is not a licensed or recommended starting dose.
* ACR20 or 70=20% or 70% improvement in rheumatoid arthritis signs and symptoms according to American College of Rheumatology (ACR) criteria.
Further information: Roche