Effect of Xinfeng capsule in the treatment of active rheumatoid arthritis: a randomized controlled trial

To explore the use of Xinfeng capsule (XFC) in the treatment of active rheumatoid arthritis (RA) and its effect on immunoglobulin titer, B cell-activating factor (BAFF) and its receptor (BAFF-R).

A multi-center randomized, double-blind, parallel-controlled study was conducted. 45 RA patients were assigned to two groups: one was treated with XFC plus the placebo for leflunomide (LEF) and the second group was treated with LEF plus XFC placebo, for 12 weeks. The clinical and laboratory parameters were collected at baseline and at 12 weeks.

After 12 weeks of treatment, patients in the two groups all showed an therapeutic effect when ACR20, ACR50 and ACR70 were compared, but the differences between two groups were not significant (P < 0.05). The serum levels of IgG1, BAFF and BAFF-R in the XFC group were lower than those in the LEF group (P < 0.05). The level IgG subtypes correlated with clinical parameters; IgG2 levels positively correlated with C-reactive protein (CRP) (P < 0.01); IgG3 levels positively correlated with white blood cell count and CRP (P < 0.01); IgG4 levels positively correlated with Complement 4 ( C4) (P < 0.01); the level of BAFF negatively correlated with Lymphocyte (LYMPH#) (P < 0.01); however, BAFF-R positively correlated with Platelet (PLT) and a1-acid glycoprotein (AGP) (P < 0.01).

XFC can regulate the level of BAFF/BAFF-R in active rheumatoid arthritis and improve the levels of immunoglobulins in RA patients.