In a phase 2a trial (NNC0109–0012), anti-IL-20 mAb seems to be effective particularly in the patients with seropositive RA (RF- and anti-CCP- positive) rather than seronegative RA patients, but the phase 2b trial (NCT01636843) failed because the primary efficacy endpoint was not met [91]. The gene discussed is IL20; the disease is rheumatoid arthritis.