Conventional disease-modifying anti-rheumatic drugs combined with Chinese Herbal Medicines for rheumatoid arthritis: A systematic review and meta-analysis

Rheumatoid Arthritis (RA) remains a major global public health challenge. Disease-modifying anti-rheumatic drugs (DMARDs) are standard therapeutic drugs for RA. Conventional DMARDs (c-DMARDs) are a subgroup of approved synthetic DMARDs. The c-DMARDs experienced lesser response with longer disease duration or drug exposure, and unwanted adverse events (AEs). The combination treatments (CTs) of c-DMARDs and Chinese Herbal Medicines (CHMs) were often used in RA clinical trials for increasing the therapeutic effectiveness and reducing the AEs. This systematic review aimed to evaluate the efficacy and safety of the CTs for RA. Databases were searched from inception to October 2020 for identification of randomized controlled trials (RCTs) that investigated the CTs in the management of RA. Twenty-three RCTs with 2,441 participants were included. The assessments and analyses found CTs improved American College of Rheumatology (ACR) 20 (RR: 1.33, 95% CI [1.21, 1.45], 10 studies, n=1,075) and alleviated AEs (RR: -0.40, 95% CI [-0.30, -0.53], 19 studies, n=2,011) in comparison with c-DMARDs. The CTs also significantly improved RA symptoms and patient-reported outcomes; reduced disease activity score (DAS) 28, serum acute-phase reactants and RA biomarkers. The five most commonly used herbs in included studies were Angelicae Sinensis Radix, Paeoniae Radix Alba, Cinnamomi Ramulus, Glycyrrhizae Radix et Rhizoma, and Clematidis Radix et Rhizoma. Pharmacological studies indicated these CHMs could contribute to the outcomes. The integrated CHMs potentially increased the overall effectiveness of c-DMARDs and alleviated AEs in management of RA. Large sample and rigorously designed RCTs are required for future studies.