The treatment is the first approved by the FDA to treat the 2 most common subtypes of generalized myasthenia gravis.
The FDA has approved rozanolixizumab-noli (Rystiggo)1 for generalized myasthenia gravis (gMG) in adults who are anti–acetylcholine receptor (AChR) or anti–muscle-specific tyrosine kinase (MuSK) antibody positive, which are the 2 most common subtypes of gMG.
MG causes muscle weakness and symptoms of the disease include “weakness of arm or leg muscles, double vision, drooping eyelids, and problems with speaking, chewing, swallowing and breathing.”2 Symptoms progress over time. There are approximately 36,000 to 60,000 cases in the United States.3
The approval was granted under the Priority Review designation and based on the data from the pivotal phase 3 MycarinG study. Rozanolixizumab is a humanized IgG4 monoclonal antibody delivered via a subcutaneous infusion. It is the only FDA-approved treatment for both anti-AChR and anti-MuSK antibody-positive gMG.
“gMG can cause unpredictable fluctuations in severity and frequency of symptoms, which are often debilitating and can substantially impact the lives of patients. People living with gMG often face treatment options that are broad-acting, and that have traditionally only offered symptomatic relief,” Vera Bril, BSc, MD, FRCPC, professor of medicine (neurology), University of Toronto and director of the Neuromuscular Section, Division of Neurology, University of Toronto and University Health Network in Toronto, said in a statement.1 She was also the lead investigator of the MycarinG study.
The results of the study were published in The Lancet Neurology in May 2023.4 MycarinG was a a randomized, double-blind, placebo-controlled, adaptive phase 3 study with sites in Asia, Europe, and North America. A total of 200 patients were enrolled, with 33% randomly assigned to receive rozanolixizumab 7 mg/kg, 34% receiving rozanolixizumab 10 mg/kg, and 34% receiving placebo.
From baseline to day 43, the reductions in Myasthenia Gravis Activities of Daily Living (MG-ADL) score were greater in the rozanolixizumab 7 mg/kg (least-squares mean [SE], –3.37 [0.49]) and rozanolixizumab 10 mg/kg (–3.40 [0.49]) groups than the placebo group (–0.78 [0.49]). MG-ADL assesses the impact of gMG on daily functions of 8 signs or symptoms that are typically affected in gMG.
The rozanolixizumab groups had similar proportions of patients with any treatment-emergent adverse events (TEAEs) and treatment-related TEAEs, both of which were higher than in the placebo group. Most TEAEs were mild to moderate and the most frequent were headache, diarrhea, pyrexia, and nausea.
“No 2 people living with gMG experience the disease in the same way, so we can’t take a ‘one size fits all’ approach to disease management,” said Iris Loew-Friedrich, executive vice president and chief medical officer at UCB, the manufacturer of rozanolixizumab-noli. “Disease management should be based on the clinical needs and preferences of the individual patient, and the aim of treatment is to help restore that patient’s ability to carry out activities of daily living. The approval of rozanolixizumab-noli means doctors have an additional approved treatment option for their gMG patients who have not yet found a treatment that meets their needs.”
Rozanolixizumab will be available in the United States during the third quarter of 2023, and it is currently under review by the European Medicines Agency and the Japanese Pharmaceuticals and Medical Devices Agency for the treatment of adults with gMG.
1. UCB announces U.S. FDA approval of RYSTIGGO[®] (rozanolixizumab-noli) for the treatment of adults with generalized myasthenia gravis. Press release. June 27, 2023. https://www.ucb.com/stories-media/Press-Releases/article/UCB-announces-US-FDA-approval-of-RYSTIGGOR-rozanolixizumab-noli-for-the-treatment-of-adults-with-generalized-myasthenia-gravis
2. Myasthenia gravis. Mayo Clinic. Updated June 22, 2023. Accessed June 26, 2023. https://www.mayoclinic.org/diseases-conditions/myasthenia-gravis/symptoms-causes/syc-20352036
3. Howard JF. Clinical overview of MG. Myasthenia Gravis Foundation of America. Reviewed June 2015. Accessed June 26, 2023. https://myasthenia.org/Professionals/Clinical-Overview-of-MG
4. Bril V, Drużdż A, Grosskreutz J, et al; MG0003 study team. Safety and efficacy of rozanolixizumab in patients with generalised myasthenia gravis (MycarinG): a randomised, double-blind, placebo-controlled, adaptive phase 3 study. Lancet Neurol. 2023;22(5):383-394. doi:10.1016/S1474-4422(23)00077-7