Rituximab therapy for refractory interstitial lung disease related to antisynthetase syndrome

Summary Objective To report our experience using rituximab as therapy for refractory antisynthetase syndrome (ASS)-associated interstitial lung disease. Methods We retrospectively evaluated the medical records of 7 ASS patients with refractory interstitial lung disease, which had previously failed to respond to prednisone and/or other cytotoxic drugs. All 7 patients received rituximab therapy, i.e.: 1 g at days 0 and 14 and at 6-month follow-up. Data on pulmonary symptoms, pulmonary function tests and high resolution computed tomography (HRCT) scan of the lungs were collected: 1) before rituximab initiation; and 2) at 6-month and one-year follow-up after the first infusion of rituximab. Results At one-year follow-up, ASS patients had resolution ( n  = 2) or improvement of pulmonary clinical manifestations. Patients also exhibited significant improvement of interstitial lung disease parameters: 1) on pulmonary function tests: FVC ( p  = 0.03) and DLCO ( p  = 2 × 10 −5 ); 2) and HRCT-scan of the lungs. Due to clinical resolution/improvement of interstitial lung disease, the median daily dose of oral prednisone could be reduced in these 7 ASS patients at one-year follow-up, compared with baseline (20 mg/day vs. 9 mg/day; p  = 0.015). Conclusion Our findings suggest that rituximab may be a helpful therapy for refractory interstitial lung disease in patients with ASS.