Efficacy and safety of baricitinib for active rheumatoid arthritis in patients with an inadequate response to conventional synthetic or biological disease-modifying anti-rheumatic drugs: A meta-analysis of randomized controlled trials

The purpose of the present meta-analysis was to assess the efficacy and safety of baricitinib for active rheumatoid arthritis (RA) in patients with an inadequate response or intolerance to conventional synthetic or biological disease-modifying anti-rheumatic drugs (DMARDs). A total of 7 randomized controlled trials (RCTs) were included. The primary effective outcome was the RA improvement to reach an American College of Rheumatology 20% (ACR20) response rate. The safety outcomes were composed of clinical laboratory parameters. All patients included received 4 mg baricitinib once daily to treat RA for 12 or 24 weeks. The ACR20 response rate in the baricitinib group was significantly higher compared with that in the control group at 12 weeks [relative risk (RR), 1.77; 95% confidence interval (CI), 1.62-1.94; P<0.00001] and 24 weeks (RR, 1.76; 95% CI, 1.48-2.10; P<0.00001). Similarly, other effective outcome measures also exhibited significant improvements in the baricitinib group compared with those in the placebo group. Regarding the safety outcomes, no significant difference in adverse events (AEs) was identified at 12 weeks (P=0.14), but AEs were significantly higher in the baricitinib group compared with those in the control group at 24 weeks (P=0.03). Most laboratory values were significantly different between the baricitinib and placebo groups; however, the clinical significance of these changes remains to be determined. In summary, the present meta-analysis demonstrated that 4 mg baricitinib once daily was beneficial in patients with active RA with an inadequate response or intolerance to conventional synthetic or biological DMARDs. More high-quality RCTs are required to determine the sustained efficacy and the safety of baricitinib.