Meta-Analysis of Proptosis Response in Thyroid Eye Disease: Efficacy of EUGOGO Recommended Treatment Regimen With IV Methylprednisolone

Background: The European Group on Graves’ Orbitopathy (EUGOGO) recommends intravenous methylprednisolone (IVMP) as the first line treatment for moderate-to-severe active thyroid eye disease (TED). While many studies with varying doses of IVMP have reported improvements in inflammation, via clinical activity score (CAS) reduction, the reported improvements in the major progressive outcome of TED, proptosis, vary widely. A reduction in proptosis of ≥2 millimeter (mm) is considered by clinicians and EUGOGO as clinically meaningful. A meta-analysis of existing literature on use of IVMP in TED management, specifically proptosis response, was conducted. Methods: PubMed and Embase were searched for relevant randomized controlled trials (RCTs) and observational studies that included patients with moderate-to-severe active TED receiving treatment with the EUGOGO recommended dose of IVMP (4.5-5g over 12 weeks) from the inception of the databases to date of search (October 2020); regular alerts were established to capture any recent studies. The outcome of interest was change from baseline to week 12 in proptosis in mms. Single-arm meta-analyses were conducted for IVMP using the DerSimonian-Laird random-effects models and forest plots were generated. Pooled means and corresponding 95% confidence intervals (CIs) were calculated. The primary analysis included all identified studies. Sensitivity analyses were conducted based on study design, study characteristics (smoking status), and methodologies (weighted Bayesian meta-analyses based on study design). Results: The search retrieved 12 studies (10 single-center, 8 RCTs, 4 observational studies: 7 from China, 4 from EU, 1 from Turkey), reporting proptosis for 498 patients that were used for the meta-analysis. No placebo-controlled study with the EUGOGO recommended dose of IVMP was found. All studies included patients who were 18 years or older with moderate-to-severe TED and most (n=11) studies included patients with CAS of ≥3. For studies that reported this data, the mean or median (if mean not reported) age ranged from 35 to 52 years and duration of TED symptoms ranged from 4 to 13.6 months. Treatment with IVMP resulted in a reduction of 0.94 mm (95% CI: -1.57 to -0.32) in proptosis from baseline to week 12. The results from the sensitivity analyses were aligned with those from the primary analysis. Conclusions: Among patients with moderate-to-severe TED, this meta-analysis found the EUGOGO-recommended dose of IVMP may result in modest, but not clinically meaningful, improvements in proptosis. However, these results should be interpreted with caution given the paucity of published data and the lack of risk/benefit analyses with glucocorticoid use as compared to the recently FDA-approved therapy, teprotumumab, for the treatment of TED.