Rituximab as a rescue treatment added on mycophenolate mofetil background therapy in progressive systemic sclerosis associated interstitial lung disease unresponsive to conventional immunosuppression

Abstract

ObjectiveTo test whether the use of rituximab (RTX) is effective and safe as a rescue therapy add-on treatment to mycophenolate (MMF) in patients with progressive systemic sclerosis-associated interstitial lung disease (SSc-ILD) in whom conventional immunosuppressants (IS) have failed. MethodsLongitudinal retrospective observational study of a cohort of patients with SSc-ILD that started treatment with RTX due to ongoing lung function impairment despite treatment with glucocorticoids and IS (cyclophosphamide and/or MMF). All patients were treated with 2 or more cycles of RTX and evaluated for at least 12 months. ResultsTwenty-four patients were included. Before initiation of RTX the mean decline in%pFVC and %pDLCO during the previous 2 years (delta) was −12.9% and −12.5%, respectively. After 1 year of treatment with RTX, a significant improvement in %pFVC (∆+8.8% compared to baseline, 95% CI: −13.7 to −3.9; p = 0.001) and%pDLCO (∆+4.6%, 95% CI: −8.2 to −0.8; p = 0.018) was observed. In addition, there was a significant reduction in the median dose of prednisone and it could be suspended in 25% of patients.At 2 years of treatment, RTX had been discontinued in 9 patients (due to adverse events in 3 cases and inefficacy in 6). In the 15 patients (62.5%) that completed 24 months of therapy, the statistically significant amelioration in pulmonary function test parameters was maintained: ∆%pFVC: +11.1% (95% CI: −17.6 to −4.5; p = 0.003) and ∆%pDLCO: +8.7% (95% CI: −13.9 to −8.3; p = 0.003). ConclusionBased on our results, RTX's use as an add-on treatment to MMF appears to be effective as a rescue therapy in patients with a more aggressive SSc-ILD phenotype.