Astellas Pharma has launched the JAK blocker Smyraf (peficitinib hydrobromide) in Japan for the treatment of rheumatoid arthritis, as a later-line therapy. The therapy was approved in March 2019, based mainly on the results from two Phase III trials, RAJ3 and RAJ4. It is estimated that there are up to 1 million people in Japan with rheumatoid arthritis.