A RANDOMIZED DOUBLE-BLIND TRIAL OF PREDNISOLONE ALONE OR WITH AZATHIOPRINE IN MYASTHENIA-GRAVIS

We compared prednisolone (PRED) and azathioprine (AZA) versus predniso lone alone in the treatment of MG. Prednisolone alone or combined with azathioprine is widely used in the treatment of MG, but no randomized placebo-controlled comparative trial data are available. The predniso lone dose and clinical outcome were compared in a multicenter randomiz ed double-blind study of 34 MG patients who were followed up for 3 yea rs. One group (PRED + AZA) received prednisolone (on alternate days) p lus azathioprine (2.5 mg/kg); the other group received prednisolone on alternate days plus placebo (PRED + PLAC). Initial high-dose predniso lone (1.5 mg/kg on alternate days) was tapered at remission to the min imal dose required to maintain remission. The prednisolone dose did no t differ significantly between the two groups at 1 year (median values : PRED + AZA, 37.5 mg on alternate days; PRED + PLAC, 45 mg on alterna te days) but was reduced at 2 and 3 years in the PRED + AZA group (med ian value at 3 years: PRED + AZA, 0 mg on alternate days; PRED + PLAC, 40 mg on alternate days; p = 0.02). Relapses and failures to remit ov er the 3 years were more frequent in the PRED + PLAC group. There was a sharp rise in the anti-acetylcholine receptor (AChR) titers in the P RED + PLAC group at 2 years. Incidence of side effects was slightly le ss in the PRED + AZA group. Azathioprine as an adjunct to alternate da y prednisolone in the treatment of antibody-positive generalized MG re duces the maintenance dose of prednisolone and is associated with fewe r treatment failures, longer remissions, and fewer side effects.