Interstitial lung disease (ILD) is a major cause of morbidity and mortality in patients with idiopathic inflammatory myopathies (IIM). Glucocorticoids are the initial standard treatment. However, many patients fail to respond and continue to progress despite treatment with high dose glucocorticoids. The efficacy of rituximab has been suggested in case reports and case series of refractory antisynthetase (AS) syndrome, but data on patients without auto-antibodies or with rapidly progressive ILD are scarce. We report a case of rapidly progressive dermatomyositis (DM) associated ILD treated successfully with B-cell depletion therapy.