The Japanese Ministry of Health, Labour and Welfare (MHLW) has granted marketing approval for Olumiant (baricitinib) 2mg and 4mg tablets for the treatment of rheumatoid arthritis (RA).

Olumiant is a once-daily oral JAK inhibitor jointly developed and commercialised by US-based pharmaceutical companies Eli Lilly and Incyte.

RA is an autoimmune disease that causes inflammation and progressive destruction of joints.

The indicated therapy can be used to treat RA patients with inadequate response to standard-of-care therapies, as well as for the prevention of structural injury of joints.

Eli Lilly Bio-Medicines president Christi Shaw said: "Today is an important milestone for the RA community in Japan.

"Olumiant has been shown to provide effective relief of RA symptoms in people who do not respond to standard treatments, as well as prevent the structural damage to joints that makes RA a progressive, debilitating disease."

Olumiant is currently undergoing clinical studies for inflammatory and autoimmune diseases.

The MHLW approval is based on the results of the baricitinib development programme that involves four Phase III clinical trials.

The trials involve various populations of more than 3,000 moderate-to-severe RA patients worldwide, including more than 500 patients from Japan.

Clinical studies have demonstrated the effectiveness of baricitinib in improving the signs and symptoms of RA compared to standard-of-care therapies.

Incyte chief medical officer Dr Steven Stein said: "The phase III clinical trial programme of Olumiant consistently showed significant improvement in clinical signs and symptoms of RA in a wide range of RA patients with a diverse treatment history."

The marketing authorisation of Olumiant in the country will provide a $15m milestone payment from Eli Lilly to Incyte.