Two-year Efficacy and Safety of Subcutaneous Tocilizumab in Combination with Disease-modifying Antirheumatic Drugs Including Escalation to Weekly Dosing in Rheumatoid Arthritis
This 2-year Phase 3 study, proved that subcutaneous tocilizumab (TC-SC) has long-term efficacy and an acceptable safety profile.
Patients enrolled had been previously diagnosed with RA with an inadequate response to DMARDs. Patients were randomised 2:1 to receive doses of TCZ-SC (n=437) or PBO (n=219) every other week for 6 months. After this time, all patients received TCZ-SC. Escape therapy, defined as weekly TCZ-SC, was available to patients from Month 3. Efficacy was analysed using ACR response rates, DAS28 remission, HAQ-DI scores and mTSS. Safety data were analysed by the occurrence of adverse events.
More PBO-TCZ-SC patients switched to escape therapy during treatment compared to TCZ-SC patients (45% vs 21%, respectively). 41% of these PBO-TCZ-SC patients escaped prior to Month 6, compared to 16% of TCZ-SC patients.
PBO-TCZ-SC patients reported improvements in efficacy after Month 6, and by Month 8 efficacy data were similar to patients given TCZ-SC initially. ACR20 responses were maintained until Month 24 in TCZ-SC patients and in PBO-TCZ-SC patients. Escape therapy patients also showed clinical improvement in ACR response rates, but this was not as high as other treatment groups.
Mean annualised progression rate for mTSS decreased through Month 12 for both treatment groups, and was 2-fold higher in the PBO-TCZ-SC group than in the TCZ-SC group (0.57 vs 0.29, respectively). The adverse event profile of TCZ-SC escape therapy patients was similar to patients who continuously received TCZ-SC q2w and patients who escaped PBO prior to Month 6.
The authors concluded that the sustained ACR responses supported the long-term efficacy of TCZ-SC q2w therapy. All safety data collected were consistent with the current safety profile of intravenous TCZ and were comparable to other long-term studies in TCZ-SC.