Health-related quality of life in patients with giant cell arteritis treated with tocilizumab in a phase 3 randomised controlled trial.

Background: Patients with giant cell arteritis (GCA) treated with tocilizumab (TCZ) every week or every other week and prednisone tapering achieved superior rates of sustained remission to patients treated with placebo and prednisone tapering in a randomised controlled trial. Health-related quality of life (HRQOL) in patients from this trial is now reported.

Methods: Exploratory analyses of SF-36 PCS and MCS and domain scores, PtGA and FACIT-Fatigue were performed in patients treated with weekly subcutaneous TCZ 162 mg plus 26-week prednisone taper (TCZ-QW + Pred-26) or placebo plus 26-week or 52-week prednisone tapers (PBO + Pred-26 or PBO + Pred-52). These analyses were performed on responder and non-responder patients, including those who achieved the primary outcome and those who experienced flare and received escape prednisone doses.

Results: Baseline SF-36 PCS, MCS and domain scores were low, indicating impaired HRQOL related to GCA. At week 52, least squares mean (LSM) changes in PCS scores improved with TCZ-QW + Pred-26 but worsened in both PBO + Pred groups (p <  0.001). LSM changes in MCS scores increased with TCZ-QW + Pred-26 versus PBO + Pred-52 (p < 0.001). Treatment with TCZ-QW + Pred-26 resulted in significantly greater improvement in four of eight SF-36 domains compared with PBO + Pred-26 and six of eight domains compared with PBO + Pred-52 (p < 0.01). Improvement with TCZ-QW + Pred-26 met or exceeded minimum clinically important differences (MCID) in all eight domains compared with five domains with PBO + Pred-26 and none with PBO + Pred-52. Domain scores in the TCZ-QW + Pred-26 group at week 52 met or exceeded age- and gender-matched normative values (A/G norms). LSM changes from baseline in FACIT-Fatigue scores increased significantly with TCZ-QW + Pred-26, exceeding MCID and A/G norms (p < 0.001).

Conclusions: Patients with GCA receiving TCZ-QW + Pred-26 reported statistically significant and clinically meaningful improvement in SF-36 and FACIT-Fatigue scores compared with those receiving prednisone only. Improvements in the TCZ-QW + Pred-26 group led to recovery of HRQOL to levels at least comparable to those of A/G-matched normative values at week 52 and exceeded normative values in five of eight domains.

Trial Registration: ClinicalTrials.gov, NCT01791153. Date of registration: February 13, 2013.