This is a phase 2, multicenter, randomized, double-blind, placebo-controlled, parallel-group, efficacy and safety study in 30 patients with erosive osteoarthritis of interphalangeal joints. The study is composed of 4 phases: a pre-randomization phase for up to 35 days followed by a 91-day randomized, double-blind two arm treatment phase, followed by a 77-day open label treatment phase for all study participants and a 28-day observational follow-up phase. Efficacy of the double blind and open label phase will be assessed at study day 84 and 168 after treatment start respectively.