Myasthenia Gravis

A Multi-Center, Single-Blind, Randomized Study Comparing Thymectomy to No Thymectomy in Non-Thymomatous MG Patients on Prednisone (MGTX)

Study Design: Multi-Centered, Single-Blind, Randomized, Two Arm Trial

Study Objectives: Thymectomy and Myasthenia Gravis: a clinical challenge.

Myasthenia gravis (MG) is an autoimmune disease in which 85% of patients have antibodies to muscle acetylcholine receptors (AchR-Ab) that interfere with neuromuscular transmission. MG frequently causes severe disability that can be life-threatening. Thymectomy has been established therapy in non-thymomatous MG since 1940, based on retrospective, non-randomized studies. Corticosteroids are now being used increasingly either as the sole treatment or in conjunction with thymectomy. Both therapies have associated adverse effects, and indications for their use based on randomized trial data are lacking.

There is therefore an important clinical need to establish the place of thymectomy in the management of MG patients receiving prednisone, specifically extended transsternal thymectomy [ETTX] because it provides the greatest thymic resection with low morbidity and limited risk of nerve injury. To address this, we aim to answer three questions in a rigorously executed 5 year study in which each patient will be followed for at least 3 years:

Question 1: Does ETTX combined with prednisone result in a greater improvement in myasthenic weakness, compared to prednisone alone?

Question 2: Does ETTX combined with prednisone result in a lower total dose of prednisone, thus decreasing the likelihood of concurrent and long-term toxic effects, compared to prednisone alone?

Question 3: Does ETTX combined with prednisone enhance quality of life by reducing adverse events and symptoms associated with the therapies, compared to prednisone alone?

Key Personnel:
John Newsom-Davis, MD Study Chair
Gil Wolfe, MD Vice Chair
Alfred Jaretzki MD Surgical Chair
Henry Kaminski, MD Ancillary Studies

Data Coordinating Center
Gary Cutter, PhD Director
Inmaculada Aban, PhD Deputy Director
Greg Minisman, MA Project Manager