Efficacy of tripterygium glycosides (TG) in rheumatoid arthritis as a disease-modifying anti-rheumatic drug (DMARD) in combination with conventional DMARDs: A systematic review and meta-analysis of randomized controlled trials

To explore efficacy and safety, as well as efficacy mechanisms, main efficacy characteristics, and efficacy influencing factors of TG, in combination with one conventional DMARD, to provide guidance for the clinical application of TG in treating RA. We searched the databases of PubMed, Embase, Web of Science, Cochrane Library, Ovid, Scopus, Clinicaltrials.gov, CNKI, Wanfang, SinoMed, VIP, Chinese Clinical Trial Registry, KTKP, and J-STAGE to August 12, 2022. All included studies were analyzed with Stata 16.0 software and Review Manager 5.4 software according to the PRISMA Statement. Thirty-eight randomized controlled trials (RCTs) were included. Combined TG was superior in 28-joint count Disease Activity Score (DAS28) and American College of Rheumatology 50 response (ACR50) and did not increase adverse events (AEs). Combined TG significantly suppressed interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). And combined TG showed significant advantages in improving tender joint count (TJC), swollen joint count (SJC), pain score, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and physician’s and patient’s global assessments of disease activity. However, the average age of the intervention population, treatment course, the combined DMARDs category, and the risk of bias were important factors influencing the above effects. The combination of TG is superior to conventional DMARD monotherapy in improving RA conditions with a good safety profile. This effect is closely related to the mechanism of TG reducing IL-1, IL-6 and TNF-α. And the combination of TG shows better effect in all aspects such as improving joint signs, symptoms, inflammatory indicators, and overall health. But for those under 45 years of age, with short-term intermittent dosing, in combination with MTX may be more beneficial for TG to show better efficacy.