Subcutaneous Ig Maintenance Therapy for Myasthenia Gravis

The study is a pilot study to ascertain the feasibility and tolerability of subcutaneous immunoglobulin (SCIG or IGSC) as a maintenance therapy for patients with non-thymomatous MG patients (MGFA class II-IV) at entry, aged 18-80 years, positive acetylcholine receptor antibody, receiving greater than 30mg of prednisone daily. Patients may or may not be receiving anticholinesterase agents. The neurologist principal investigator at each site will have the overall responsibility for study performance is designated the medical coordinator (MC). The MC will assess patients from the sites clinic populations and identify potential subjects for inclusion and exclusion criteria. Once a subject is identified and provided informed consent to participate the Visit Schedule will be initiated. At the initial visit the MC will perform the acetylcholine receptor antibody level, and record the prednisone and anticholinesterase doses. The MC will be responsible for assessment of adverse events. The research coordinator will arrange for the initial laboratory testing at the patient's local Quest, where the blood will be drawn. Baseline lab tests to be done will include IgA level to evaluate for deficiency, IgG level, CBC, AchR antibody, pregnancy tests in women, LFT's, PT/PTT and BUN/Creatinine. The patient will complete the SF-36 quality of life, MG, and MGFA ADL The research coordinator will be responsible for training subjects in performance of IGSC infusion. Subjects will have outpatient clinic assessments in one week and then monthly for the remainder of the study. Patients will receive 2gms/kg divided over 4 weeks initially and then will be given 250mgs/kg/wk for total of 6 months. This is similar to the standard IV treatment for patients which is 2 gm/kg given over 2-5 days for the initial dose. After the initial dose, a patient is started on monthly IV maintenance dose of 1 gm/kg each month given over 1-3 days. The subject will be evaluated monthly for assessment of whether minimal manifestation (MM) status has been reached, which then allows reduction of corticosteroids by 5mg or more if clinically indicated. The MC will record adverse events and symptoms. The dose of anticholinesterase drugs will be decreased at the discretion of the MC. The prednisone dose will be decreased unless the MM status is lost; in that situation the prednisone dose will be increased 10mg every 2 weeks until the MM is again achieved. Titration of the prednisone and cholinesterase inhibitor medications will be at the discretion of the physician and will be based on the patient's symptoms as measured by symptoms and examination, leading to a determination of the MM. The patient will complete the SF-36 quality of life assessment.