Rituximab for systemic sclerosis: arrest of pulmonary disease progression in five cases Results of a lower dosage and shorter interval regimen

Systemic sclerosis (SSc) can be a devastating disease with lethal complications such as interstitial lung disease (ILD). Therapeutic strategies include cyclophosphamide but patients are frequently refractory even to this aggressive immunosuppressant. Lafyatis et al published a 6-month open observational study of 15 patients with diffuse scleroderma receiving one course of rituximab (2 1 g within 2 weeks) (1, 2). They found no significant clinical improvement in the extent of thickened skin and no significant benefit in pulmonary functional tests. Daoussis et al published a 1-year randomized controlled trial, in which eight scleroderma patients improved on skin fibrosis and pulmonary function (2, 3). This success was prolonged in an open 2-year observation of patients receiving four weekly pulses of 375 mg/m rituximab after 6, 12, and 18 months (2, 4). We report here a significant benefit with a different dosing regimen in a small open series of scleroderma patients with ILD. Five consecutive patients with anti-topoisomerase I (Scl-70)-positive diffuse scleroderma and ILD failed to respond to conventional therapy with intravenous cyclophosphamide. Demographic data and patients’ characteristics are shown in a Table (attached as supplementary material). All five patients received 500 mg rituximab on day 0 and day 14 every 3 months for a period of 1 year. Changes in the modified Rodnan skin score (mRSS) and diffusion lung capacity of carbon monoxide (DLCO) are shown in Figure 1.