Effect of Tocilizumab on Fatigue and Bone Mineral Density in Patients with Rheumatoid Arthritis

Background: Chronic fatigue is common among patients with rheumatoid arthritis (RA), affecting quality of life. Osteoporosis is a prevalent co-morbidity in RA patients. Objectives: To assess the effect of long-term treatment with tocilizumab on fatigue and bone mineral density (BMD) in RA patients with inadequate response to synthetic or biologic disease-modifying anti-rheumatic drugs. Methods: In this multicenter, open-label, non-controlled, single arm study, patients >= 18 years of age received intravenous tocilizumab 8 mg/kg every 4 weeks for 96 weeks. The primary outcome was the change in Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue score from baseline to weeks 24, 48, 72, and 96. BMD was assessed before and 96 weeks after treatment. Results: The study comprised 145 patients (mean age 53.4 +/- 13.4 years, 83.4% women). Of these, 88 (60.7%) completed the 2 year treatment period. The mean FACIT-Fatigue score improved consistently starting from week 4 and showed a statistically significant increase of 5.0 +/- 9.7, 6.8 +/- 10.5, 7.3 +/- 10.9, and 7.3 +/- 10.4 from baseline to weeks 24, 48, 72, and 96, respectively (P < 0.0001). Mean BMD of femoral neck and total spine remained stable. Disease activity, acute phase reactants, and composite efficacy measures decreased during the study, while hemoglobin levels increased. Adverse events and serious adverse events were as expected for the known and previously described data. Conclusions: Tocilizumab therapy for 2 years significantly and clinically decreased fatigue. BMD remained stable and no new safety issue was reported.