2023 American Academy of Neurology Abstract Website

Vera Bril¹, Artur Drużdż², Julian Grosskreutz³, Ali A. Habib⁴, Renato Mantegazza⁵, Kimiaki Utsugisawa⁶, John Vissing⁷, Tuan Vu⁸, Marion Boehnlein⁹, Maryam Gayfieva¹⁰, Bernhard Greve⁹, Franz Woltering⁹, Henry J. Kaminski¹¹
¹University Health Network, ²Department of Neurology, Municipal Hospital Poznań, ³Precision Neurology, Department of Neurology, University of Lübeck, ⁴MDA ALS and Neuromuscular Center, University of California, ⁵Fondazione IRCCS, Istituto Nazionale Neurologico Carlo Besta, ⁶Department of Neurology, Hanamaki General Hospital, ⁷Department of Neurology, Rigshospitalet, University of Copenhagen, ⁸Department of Neurology, University of South Florida Morsani College of Medicine, ⁹UCB Pharma, Monheim, Germany, ¹⁰UCB Pharma, Slough, UK, ¹¹George Washington University

Objective:

Assess efficacy of cyclic rozanolixizumab treatment for generalized myasthenia gravis.

Background:

In the Phase 3 MycarinG (NCT03971422; MG0003) study, 1 cycle (6 weekly SC infusions) of the humanized IgG4 mAb FcRn inhibitor rozanolixizumab 7mg/kg or 10mg/kg significantly improved MG-ADL, MGC and QMG scores versus placebo. After MycarinG, patients could enrol in OLEs (MG0004 then MG0007, or directly in MG0007).

Design/Methods:

MG0004 (NCT04124965) was an OLE of up to 52 weeks of weekly rozanolixizumab infusions. In MG0007 (NCT04650854), after an initial cycle, subsequent cycles were administered on symptom worsening (investigator’s discretion; e.g. MG-ADL increase ≥2/QMG increase ≥3; “symptom-driven cycles”). Pooled data are reported across MycarinG, MG0004 (first 6 weeks) and MG0007 (interim analysis) for patients with ≥2 symptom-driven cycles (up to 6 cycles; efficacy) and with ≥1 cycle (safety).

Results:

127/196 (64.8%) patients received ≥2 symptom-driven cycles of rozanolixizumab (69 patients 7mg/kg and 58 patients 10mg/kg). Treatment response was consistent across cycles 1–6: Mean Day 43 CFB in MG-ADL score for all rozanolixizumab-treated patients was: Cycle 1 (n=127): −3.7; cycle 2 (n=127): −3.9; cycle 3 (n=98): −3.4; cycle 4 (n=75): −3.8; cycle 5 (n=51): −3.9; cycle 6 (n=32): −4.5. Mean Day 43 CFB in QMG score was: Cycle 1 (n=127): −5.4; cycle 2 (n=125): −4.7; cycle 3 (n=97): −4.7; cycle 4 (n=74): −5.1; cycle 5 (n=51): −4.5; cycle 6 (n=32): −6.3. MGC reductions were consistent across cycles. Patients with >1 year participation initiated a median of 4 cycles per year in the first year. 169/188 (89.9%) patients receiving ≥1 cycle of rozanolixizumab reported ≥1 TEAE, with 103 (77.4%) and 120 (91.6%) patients experiencing TEAEs with a rozanolixizumab dose of 7mg/kg and 10mg/kg, respectively (most were mild-to-moderate).

Conclusions:

Rozanolixizumab efficacy was maintained over up to six 6-week treatment cycles across multiple MG-specific outcomes, with an acceptable safety profile following repeated cyclic treatment. Funding: UCB Pharma.