1. Phase 2 Trial of Rituximab in Acetylcholine Receptor Antibody-Positive Generalized Myasthenia Gravis: The BeatMG Study
- Author
-
Merit Cudkowicz, Richard J. Barohn, Gil I. Wolfe, NeuroNEXT Nn BeatMG Study Team, Brenda Pearson, Muhammad Al-Lozi, David P. Richman, David A. Hafler, Michael Benatar, Kevin C. O’Connor, Robin Conwit, A. Gordon Smith, Eroboghene E. Ubogu, Richard Nowak, Emma Ciafaloni, Liz Uribe, Jonathan Goldstein, Mazen M. Dimachkie, Miriam Freimer, Michael E. Shy, Anthony A. Amato, Sharon P. Nations, Aditi Sharma, Jon W. Yankey, Ted M. Burns, Christopher S. Coffey, Laura Ann Sams, John T. Kissel, Dianna Quan, and Volkan Granit
- Subjects
medicine.medical_specialty ,Randomization ,Clinical Trials and Supportive Activities ,Clinical Sciences ,Placebo ,Rare Diseases ,Prednisone ,Clinical Research ,Internal medicine ,medicine ,Generalized myasthenia ,Cancer ,NeuroNEXT NN103 BeatMG Study Team ,Neurology & Neurosurgery ,business.industry ,Neurosciences ,Evaluation of treatments and therapeutic interventions ,Regimen ,Acetylcholine receptor antibody ,Steroid use ,6.1 Pharmaceuticals ,Rituximab ,Cognitive Sciences ,Neurology (clinical) ,business ,medicine.drug ,Research Article - Abstract
Background and ObjectiveTo determine whether rituximab is safe and potentially beneficial, warranting further investigation in an efficacy trial for acetylcholine receptor antibody-positive generalized myasthenia gravis (AChR-Ab+ gMG).MethodsThe B-Cell Targeted Treatment in MG (BeatMG) study was a randomized, double-blind, placebo-controlled, multicenter phase 2 trial that utilized a futility design. Individuals 21–90 years of age, with AChR-Ab+ gMG (MG Foundation of America Class II–IV) and receiving prednisone ≥15 mg/d were eligible. The primary outcome was a measure of steroid-sparing effect, defined as the proportion achieving ≥75% reduction in mean daily prednisone dose in the 4-weeks prior to week 52 and with clinical improvement or no significant worsening as compared to the 4-week period prior to randomization. The coprimary outcome was safety. Secondary outcomes included MG-specific clinical assessments. Fifty-two individuals were randomized (1:1) to a 2-cycle rituximab/placebo regimen, with follow-up through 52 weeks.ResultsOf the 52 participants included, mean ± SD age at enrollment was 55.1 ± 17.1 years; 23 (44.2%) were women and 31 (59.6%) were Myasthenia Gravis Foundation of America Class II. The mean ± SD baseline prednisone dose was 22.1 ± 9.7 mg/d. The primary steroid-sparing outcome was achieved in 60% of those on rituximab vs 56% on placebo. The study reached its futility endpoint (p = 0.03), suggesting that the predefined clinically meaningful improvement of 30% due to rituximab over placebo was unlikely to be achieved in a subsequent, larger trial. No safety issues were identified.DiscussionAlthough rituximab was safe and well-tolerated, these results suggest that there is a low probability of observing the defined clinically meaningful steroid-sparing effect over a 12-month period in a phase 3 trial of mild to moderately symptomatic AChR-Ab+ gMG.Classification of EvidenceThis study provides Class I evidence that for mild to moderate AChR-Ab+ gMG, compared with placebo, rituximab is safe but unlikely to reduce steroid use by an absolute difference of at least 30% at 1 year.Trial Registration InformationClinicalTrials.gov identifier: NCT02110706.
- Published
- 2022