Low-dose rituximab combined with a short course of intravenous methylprednisolone is an effective and safe alternative to the standard use of high-dose steroids in thyroid eye disease, according to study findings published in Clinical Endocrinology.
Current guidelines recommend the use of intravenous glucocorticoids as the first-line treatment for active thyroid eye disease, but despite its efficacy in suppressing inflammation, up to one-third of patients do not respond to therapy and 10% to 20% have relapse once the treatment stops. Glucocorticoids are also associated with a range of potentially serious adverse events. The monoclonal antibody rituximab has been shown to lower inflammation in active thyroid eye disease, but optimal dosing has not yet been established. In this study, the efficacy of intervention with a targeted immunomodulatory therapy was evaluated in a small retrospective study of 12 patients with thyroid eye disease.
The cohort received a 100-mg infusion of rituximab plus a steroid-sparing agent if there was a clinical indication for it. The clinical activity score; vision, inflammation, strabismus, and appearance (VISA) overall severity score; and Oxford Quality of Life score were recorded at each visit. Patients with a VISA score of ≥3 points were classified as having active thyroid eye disease.
After a mean follow-up of 6.3 months, clinical activity score was significantly reduced in the cohort (mean score, 5.08 to 1.58; P <.001), as was mean VISA overall severity score, which declined by 50% from 12 to 6 points (P <.001). The mean cumulative dose of intravenous methylprednisolone was 2.3 g. Treatment with rituximab induced significant CD19+ depletion, indicating an effect on B cells (n = 8; P <.001). There was not, however, a significant reduction in thyrotropin receptor antibody levels (n = 8; P =.06). The only adverse event was a transient infusion-related rash experienced by 4 patients, which resolved with chlorphenamine. Quality of life scores did not differ markedly before and after treatment.
“Our treatment protocol significantly reduces overall steroid load as well as the duration of treatment required in the hospital setting,” concluded the researchers, although they add that the “small number of patients and the lack of randomization are limitations” and that a large multicenter randomized controlled trial is needed.
Insull EA, Sipkova Z, David J, Turner HE, Norris JH. Early low dose rituximab for active thyroid eye disease: an effective and well tolerated treatment [published online March 13, 2019]. Clin Endocrinol (Oxf). doi:10.1111/cen.13970