A Dose Response Study to Evaluate the Efficacy and Safety of Oral AP1189 Administered in Disease-Modifying Anti-Rheumatic Drug (DMARD) naïve Participants Participants With Early Rheumatoid Arthritis

The purpose of the trial is to evaluate the efficacy, safety and tolerability of 12 weeks daily treatment of oral AP1189 at the doses of 40, 70, or 100 mg in combination with oral MTX compared to oral MTX alone. The aim is to have 240 participants randomized to one of the 4 treatment groups, in a 1:1:1:1 ratio and treated with both AP1189/Placebo and MTX.