Effect and Safety of Benzathine Penicillin Combined With Etanercept on Spondyloarthritis

This trial is a randomised, double-blinded, placebo-controlled, polycentric study. The study consisted of a screening period (up to 2 weeks before randomization), a treatment period (24 weeks), and 5 follow-up visits (Weeks 0, 6, 12,18 and 24). After a 2-week preparation period, 340 patients with SpA will be randomly and equally assigned to either experimental group consisting of BPG (injection form, 1.2 million units of intramuscular injection, once every two weeks) with ETN (injection form, 25mg of hypodermic injection, twice a week) or the control group consisting of placebos (injection form, once every two weeks) with ETN (injection form, 25mg of hypodermic injection, twice a week),with treatment lasting for 12 weeks. After 12 weeks of treatment, the label will be opened, and all patients will choose to use BPG combined with ETN maintenance therapy for another 12 weeks of treatment. Follow-up will be conducted at baseline, 6 weeks,12 weeks,18 weeks and 24 weeks after the end of treatment. The primary outcome is the response rate of ASAS40 in patients after 12 weeks of medication. The secondary outcomes are the severity of symptoms, disease activity, quality of life, and imaging progression scale scores of patients at each follow-up point. We will synchronize the recording of adverse events to compare the safety of the two treatment regimens