Nowadays, safety is as important as a drug’s efficacy. In particular, reaffirming the safety of drugs that require long-term administration post-approval is essential.

JAK inhibitors, which have entered the market as an oral option to treat various autoimmune diseases such as rheumatoid arthritis and ankylosing spondylitis, have been embroiled in controversy since last year.

In 2021, the US FDA had warned of increased risk of cardiovascular events and cancer on the use of Jak inhibitors, and the MFDS also issued a Dear Healthcare Professional Letter on the issue. In the end, the FDA decided to include the increased risk of major heart-related events, thrombosis, and death in the black