This is a Phase 1, multi-center, double-blind, randomized, placebo-controlled, multiple ascending dose (MAD) study.~The study will consist of a Screening Visit (Days -1 to Day 10), Treatment duration (up to 11 days) and a Follow-up/end of treatment (EOT) visit.~This MAD study will consist of 4 cohorts of 8 patients (6 active treatment and 2 matching placebo, or a 3:1 ratio), each receiving an oral dose of TCK-276 or matching placebo for 7 days (once daily (QD) under fed condition). The first cohort will be divided into 2 subgroups to implement the sentinel dosing approach.~The study duration is approximately 42 days.
The study is to evaluate the safety, tolerability, and pharmacokinetic (PK) of multiple orally administered TCK-276 in both males and females with Rheumatoid Arthritis (RA).