The effect of tocilizumab on clinical signs and laboratory findings in rheumatoid arthritis patients resistant to methotrexate

Rheumatoid arthritis (RA) is a chronic systemic autoimmune inflammatory disease that mainly affects joint damage followed by increased morbidity and mortality rates. The progressive increase of inflammation factors, especially IL-6, is seen during the course of this condition. The aim of this study was to evaluate the effect of tocilizumab (TCZ) in patients with severe to moderate resistant RA with an inadequate response to treatment with disease-modifying antirheumatic drugs (DMARDs). We also reviewed the safety of the drug and related complications. Twelve selected RA patients received 8 mg/kg of TCZ every 4 weeks for over 24 weeks; we evaluated inflammatory factor like ESR, lipid profile, comprehensive physical exam, and RA activity like Disease Activity Score (DAS) 28, Short Form (36) Health Survey (SF-36), and ACR50 to calculate the swollen and tender joint counts. DMARDs were simultaneously administered. First-level response and secondary response were defined as reaching the American College of Rheumatology 20% response criteria (ACR20) within 24 weeks of treatment and Disease Activity Score (DAS) 28, Short Form (36) Health Survey (SF-36), and ACR50, respectively. All patients achieved ACR20 after 24 weeks and 83% reached ACR50 (p < 0.001). DAS28 decreased from 6.93 ± 2.11 at baseline to 1.29 ± 0.95 at the end of 28 weeks (p < 0.001). SF-36 increased from 28 ± 1.43 to 61.42 ± 15.66 at the end of the study (p < 0.001). SF-36 physical component summary scores also increased from 42 ± 4.98 at baseline to 88.17 ± 2.96 at the end of the study (p < 0.001). We observed that TCZ caused a rapid and sustained improvement in all disease activity indicators such as CRP, ESR, swelling and tender joint count, and morning stiffness duration in RA patients’ refractory to methotrexate.