Katherine A Buzzard1, Nicholas J Meyer2, Todd A Hardy1, D Sean Riminton2, Stephen W Reddel1. 1. Department of Neurology, Concord Repatriation General Hospital, Concord West, New South Wales, 2139, Australia. 2. Department of Immunology, Concord Repatriation General Hospital, Concord West, New South Wales, Australia.
Abstract
INTRODUCTION: Myasthenia gravis (MG) can be refractory to conventional immunotherapy. We report on the efficacy and durability of intravenous (IV) remission-induction cyclophosphamide (CYC) followed by oral immunosuppression in refractory MG. METHODS: We identified 8 patients from our medical records with moderate or severe refractory MG who were treated with 6 cycles of IV CYC (0.75 g/m(2) ) every 4 weeks followed by oral immunosuppression. RESULTS: Six patients improved within 3 months of treatment. Four patients remained in clinical remission (mean follow-up 31 months). Two patients responded partially, and 1 patient relapsed after 11 months. Two patients were non-responders. CYC was well tolerated. Acetylcholine receptor antibody levels remained below pretreatment levels in patients in clinical remission. The leukocyte nadir was lower in CYC responders. CONCLUSIONS: Remission-induction IV CYC followed by oral immunosuppression is a rapid, effective, and durable treatment for refractory MG. Adding a post-CYC immunosuppressant may account for low relapse rates compared with other published series.
INTRODUCTION:Myasthenia gravis (MG) can be refractory to conventional immunotherapy. We report on the efficacy and durability of intravenous (IV) remission-induction cyclophosphamide (CYC) followed by oral immunosuppression in refractory MG. METHODS: We identified 8 patients from our medical records with moderate or severe refractory MG who were treated with 6 cycles of IV CYC (0.75 g/m(2) ) every 4 weeks followed by oral immunosuppression. RESULTS: Six patients improved within 3 months of treatment. Four patients remained in clinical remission (mean follow-up 31 months). Two patients responded partially, and 1 patient relapsed after 11 months. Two patients were non-responders. CYC was well tolerated. Acetylcholine receptor antibody levels remained below pretreatment levels in patients in clinical remission. The leukocyte nadir was lower in CYC responders. CONCLUSIONS: Remission-induction IV CYC followed by oral immunosuppression is a rapid, effective, and durable treatment for refractory MG. Adding a post-CYC immunosuppressant may account for low relapse rates compared with other published series.
Authors: Srikanth Muppidi; Kimiaki Utsugisawa; Michael Benatar; Hiroyuki Murai; Richard J Barohn; Isabel Illa; Saiju Jacob; John Vissing; Ted M Burns; John T Kissel; Richard J Nowak; Henning Andersen; Carlos Casasnovas; Jan L de Bleecker; Tuan H Vu; Renato Mantegazza; Fanny L O'Brien; Jing Jing Wang; Kenji P Fujita; James F Howard Journal: Muscle Nerve Date: 2019-03-08 Impact factor: 3.217