Drivers of New Rozanolixizumab Treatment Cycles in Patients with Generalized Myasthenia Gravis in the Phase 3 MycarinG and Open-label Extension Studies
Zabeen K. Mahuwala1, Julian Grosskreutz2, Ali A. Habib3, Renato Mantegazza4, Robert M. Pascuzzi5, Sabrina Sacconi6, John Vissing7, Tuan Vu8, Raphaelle Beau-Lejdstrom9, Bernhard Greve10, Fiona Grimson11, Thaïs Tarancón12, Vera Bril13
1Department of Neuromuscular Medicine, Epilepsy and Clinical Neurophysiology,, Department of Neuromuscular Medicine, Epilepsy and Clinical Neurophysiology, University of Kentucky, Lexington, KY, USA, 2Department of Neurology, Precision Neurology, Department of Neurology, University of Lübeck, Lübeck, Germany, 3MDA ALS and Neuromuscular Center,, MDA ALS and Neuromuscular Center, University of California, Irvine, Irvine, CA, USA, 4Department of Neuroimmunology and Neuromuscular Diseases,, Department of Neuroimmunology and Neuromuscular Diseases, Fondazione IRCCS, Istituto Nazionale Neurologico Carlo Besta, Milan, Italy, 5Neurology Department, Neurology Department, Indiana University School of Medicine, Indiana University Health, Indianapolis, IN, USA, 6Université Côte d'Azur Peripheral Nervous System & Muscle Department, Université Côte d'Azur, Peripheral Nervous System & Muscle Department, Pasteur 2 Hospital, Centre Hospitalier Universitaire de Nice, Nice, France, 7Department of Neurology, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark, 8Department of Neurology, Department of Neurology, University of South Florida Morsani College of Medicine, Tampa, FL, USA, 9UCB Pharma, Bulle, Switzerland, 10UCB Pharma, Monheim, Germany, 11UCB Pharma, Slough, UK, 12UCB Pharma, Madrid, Spain, 13University Health Network, Toronto, ON, Canada
Objective:

A post-hoc analysis to understand factors leading to initiation of a new rozanolixizumab cycle in the Phase 3 MycarinG and open-label extension (OLE) studies.

Background:

In the Phase 3 MycarinG study (NCT03971422), one 6-week cycle of rozanolixizumab significantly improved MG-ADL and QMG scores versus placebo. After MycarinG, patients could enroll in OLE studies (MG0004/NCT04124965 then MG0007/NCT04650854, or into MG0007 directly) to receive additional rozanolixizumab treatment.

Design/Methods:

Initiation of a new cycle of rozanolixizumab treatment was at the investigator’s discretion, with advisory protocol guidance to consider a new cycle when MG-ADL scores worsened by ≥2 points or QMG scores worsened by ≥3 points. MG-ADL and QMG score changes before the start of a new cycle were analyzed for patients receiving or waiting for a new cycle after initial rozanolixizumab treatment.

Results:

Overall, 145 patients were included in the analysis (patients with MG-ADL values: n=120; patients with QMG values: n=119). A new cycle of rozanolixizumab was initiated following a mean (SD) worsening in score of 3.1 (3.5) for MG-ADL and 4.1 (5.2) for QMG from the end of the first cycle to the start of the new cycle. In total, 76/145 (52.4%) and 66/145 (45.5%) patients received a new cycle of rozanolixizumab having met the definition of MG-ADL and QMG score worsening, respectively. Initiation of a new cycle of rozanolixizumab followed worsening on either scale in 34/145 (23.4%) patients, on both scales in 54/145 (37.2%) patients, and on neither scale in 32/145 (22.1%) patients.

Conclusions:
Initiation of a new rozanolixizumab cycle was generally driven by worsening in observed changes in
MG-ADL and/or QMG scores. Physicians also initiated a new cycle in some patients with MG-ADL or QMG score changes that did not meet the suggested threshold for new cycle initiation, indicating that physicians personalized treatment based on their understanding of individual patient needs. 
10.1212/WNL.0000000000205069