Mycophenolate plus methylprednisolone versus methylprednisolone alone in active, moderate-to-severe Graves' orbitopathy (MINGO): a randomised, observer-masked, multicentre trial

Summary Background European guidelines recommend intravenous methylprednisolone as first-line treatment for active and severe Graves' orbitopathy; however, it is common for patients to have no response or have relapse after discontinuation of treatment. We aimed to compare the efficacy and safety of add-on mycophenolate to methylprednisolone in comparison with methylprednisolone alone in patients with moderate-to-severe Graves' orbitopathy. Methods MINGO was an observer-masked, multicentre, block-randomised, centre-stratified trial done in two centres in Germany and two in Italy. Patients with active moderate-to-severe Graves' orbitopathy were randomly assigned to receive intravenous methylprednisolone (500 mg once per week for 6 weeks followed by 250 mg per week for 6 weeks) either alone or with mycophenolate (one 360 mg tablet twice per day for 24 weeks). The prespecified primary endpoints were rate of response (reduction of at least two parameters of a composite ophthalmic index [eyelid swelling, clinical activity score, proptosis, lid width, diplopia, and eye muscle motility] without deterioration in any other parameter) at 12 weeks and rate of relapse (a worsening of symptoms that occurred after a response) at 24 and 36 weeks. Rates of response at week 24 and sustained response at week 36 were added as post-hoc outcomes. Prespecified primary outcomes and post-hoc outcomes were assessed in the modified intention-to-treat population (defined as all patients assigned to treatment who received at least one infusion of methylprednisolone, when outcome data were available), and safety was assessed in all patients who received at least one dose of study drug. This trial is registered with the EU Clinical Trials Register, EUDRACT number 2008-002123-93. Findings 164 patients were enrolled and randomised between Nov 29, 2009, and July 31, 2015. 81 were randomly assigned to receive methylprednisolone alone and 83 to receive methylprednisolone with mycophenolate. In the intention-to-treat population at 12 weeks, responses were observed in 36 (49%) of 73 patients in the monotherapy group and 48 (63%) of 76 patients in the combination group, giving an odds ratio (OR) of 1·76 (95% CI 0·92–3·39, p=0·089). At week 24, 38 (53%) of 72 patients remaining in the monotherapy group and 53 (71%) of 75 patients remaining in the combination therapy group had responded to treatment (2·16, 1·09–4·25, p=0·026). At week 24, relapse occurred in four (11%) of 38 patients in the monotherapy group and four (8%) of 53 patients in the combination group (OR 0·71, 0·17–3·03, p=0·72). At week 36, relapse occurred in an additional three (8%) patients in the monotherapy group and two (4%) patients in the combination group (0·65, 0·12–3·44, p=0·61). At week 36, 31 (46%) of 68 patients in the monotherapy group and 49 (67%) of 73 patients in the combination group had a sustained response (OR 2·44, 1·23–4·82, p=0·011). 23 patients had 24 serious adverse events, with 11 events in ten patients in the combination group and 13 events in 13 patients in the monotherapy group. Mild and moderate (grade 1–2) drug-related adverse events occurred in 16 (20%) of 81 patients receiving monotherapy and 21 (25%) of 83 patients receiving combination therapy (p=0·48). Interpretation Although no significant difference was seen in the rate of response at 12 weeks or rate of relapse at 24 and 36 weeks, post-hoc analysis suggested that addition of mycophenolate to treatment with methylprednisolone improved rate of response to therapy by 24 weeks in patients with active and moderate-to-severe Graves' orbitopathy. Funding Novartis, Germany.