The study aims to test a new drug, IMVT-1402, for adults with rheumatoid arthritis (RA), a condition that causes pain and swelling in the joints. This study is for those whose RA is hard to treat. The study has three parts: a 5-week screening to check if you can join, a 16-week period where everyone gets the drug, and a 12-week period where you might get the drug or a placebo (a fake pill). If you do well, you can stay on the drug for another 48 weeks.

• The study lasts up to 81 weeks, including all periods.
• Participants must visit the study center regularly for check-ups.
• Participants might receive payment for their time and travel.

To join, you need to have definite RA, high levels of certain antibodies, and have tried at least two other RA treatments that didn't work. You can't join if you have had certain other diseases or have used certain other drugs recently. The study checks if the drug helps reduce symptoms by 20%, known as ACR20 response, and monitors safety and side effects.