To investigate the long-term safety and preliminary efficacy of etanercept in patients with refractory lupus arthritis.
We evaluated 43 patients in this observational cohort study. All received etanercept (50mg/week) in addition to concomitant immunosuppressive agents. Patient and disease characteristics were collected. Incidence of adverse events and the effect on autoantibody levels were evaluated. Clinical efficacy was measured by the 28-joint count and the SLEDAI-2K scores. Remission of lupus arthritis was defined by a 28-joint score = 0. Clinically inactive systemic disease was defined by a SLEDAI-2K score <4.
The total follow-up time was 93 patient-years (median: 2.3 years per patient; range: 0.4-6.8 years). Most side effects were minor and related to local reactions. Only 2 significant adverse events occurred (8%), both were of infectious nature. The rate of autoantibody production was low (18%). A mild increase in titres of ANA (2), IgG anti-dsDNA (3) and IgM anticardiolipin (aCL) (2) antibodies was observed. All anti-dsDNA antibody increments were transient and coincided with systemic flares. No vascular events occurred. In general, disease activity declined during therapy. Most patients (83%) with lupus arthritis achieved clinical remission by week 12. All patients with simultaneous serositis experienced clinical and radiological resolution of this condition. Relapses were frequent (23%), mostly mild and related to etanercept reduction. A total of 24 patients discontinued treatment, 12 of them due to clinical remission.
Long-term therapy with etanercept was relatively safe and had remarkable long-term efficacy for refractory lupus arthritis. In view of these results, further controlled trials are warranted.