Safety and Efficacy of TollB-001 Tablets in Moderate to Severe Rheumatoid Arthritis

The goal of this study is to evaluate the safety, pharmacokinetic (PK) characteristics, and preliminary efficacy of a new oral chemical drug in : adults aged 18-70 years (male or female) with moderate to severe active rheumatoid arthritis (RA), who have had inadequate response to or intolerance of at least one conventional synthetic disease-modifying antirheumatic drug (csDMARDs) . Participants will take the assigned study drug (either tollB-001 Tablets or placebo) once daily orally for 4 weeks, follow up for 1 week.