Abstract
OBJECTIVE: To evaluate the effect of tocilizumab (TCZ), an interleukin 6 receptor inhibitor, on humoral immune responses to immunisations in patients with rheumatoid arthritis (RA). METHODS: Patients with RA with inadequate response/intolerance to one or more anti-tumour necrosis factor-α agents were randomly assigned (2:1) to TCZ 8 mg/kg intravenously every 4 weeks plus methotrexate (MTX) or MTX alone up until week 8. Serum was collected before vaccination at week 3, antibody titres were evaluated at week 8, and then all patients received TCZ+MTX through week 20. End points included proportion of patients responding to ≥6/12 pneumococcal polysaccharide vaccine (PPV23) serotypes (primary) and proportions responding to tetanus toxoid vaccine (TTV; secondary) at week 8. RESULTS: 91 patients were randomised. At week 8, 60.0% of TCZ+MTX and 70.8% of MTX patients responded to ≥6/12 PPV23 serotypes, with insufficient evidence for any difference in treatments (10.8% (95% CI -33.7 to 12.0)), and 42.0% and 39.1%, respectively, responded to TTV. Two of three TCZ+MTX patients with non-protective baseline TTV antibody titres achieved protective levels by week 8. The safety profile of TCZ was consistent with previous reports. CONCLUSIONS: Short-term TCZ treatment does not significantly attenuate humoral responses to PPV23 or TTV. To maximise vaccine response, patients should be up to date with immunisations before starting TCZ treatment. CLINICALTRIALSGOV IDENTIFIER: NCT01163747.