Article Text

other Versions

PDF
Letter
Long-term benefit of rituximab in MuSK autoantibody myasthenia gravis patients
  1. Benison Keung,
  2. Kimberly R Robeson,
  3. Daniel B DiCapua,
  4. Jennifer B Rosen,
  5. Kevin C O'Connor,
  6. Jonathan M Goldstein,
  7. Richard J Nowak
  1. Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, USA
  1. Correspondence to Dr Richard J Nowak, Department of Neurology, Division of Neuromuscular Medicine, Yale University School of Medicine, PO Box 208018, 15 York Street, LCI 9th floor, New Haven, CT 06510, USA; richard.nowak{at}yale.edu

Statistics from Altmetric.com

Introduction

Despite the efficacy of standard immunotherapy, a subset of myasthenia gravis (MG) patients remains medically refractory. Muscle-specific kinase autoantibody positive (MuSK+) patients, in particular, do not respond well to treatment, exhibit more bulbar symptoms and have more frequent exacerbations as compared to acetylcholine receptor antibody positive (AChR+) patients.1 ,2 Autoreactive B cells are appropriate candidates for targeted drug therapy as they play an important role in the pathogenesis of MG.2–4 Rituximab, a chimeric monoclonal antibody that targets the CD20 antigen on B lymphocytes, is the only B cell–directed biologic currently approved for clinical use. Several groups, including our own, have observed the benefits of rituximab in both AChR+ and MuSK+ patients.2–7 The durability of this positive response has varied among different reports. One group reported sustained benefit after a mean follow-up of 31 months in the combined AChR+ and MuSK+ cohort and 40 months in the MuSK+ subpopulation.3

Here, we report our experience with the sustained effects of rituximab in nine refractory MuSK+ patients in a follow-up period ranging from 2 to 5.5 years.

Methods

A retrospective study was performed of generalised MuSK+ MG patients referred to our neuromuscular clinic from 2003 to 2011. Nine MuSK+ patients were identified with refractory disease and treated with rituximab. The group consisted of eight females and one male with a median age of 40. Patients were defined as refractory when they: (1) could not lower …

View Full Text

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.