Vyvgart (efgartigimod alfa) Shows Promise in Treating Generalized Myasthenia Gravis in Expanded Access Program
Vyvgart (efgartigimod alfa) has been found to be effective in treating adults with refractory generalized myasthenia gravis (gMG) in an expanded access program, according to a recent study published in the journal Muscle & Nerve. The study found that more than half of the patients experienced a clinically meaningful improvement in symptoms, and most were able to reduce or stop other medications. Although patients required more frequent dosing than what was used during clinical testing, Vyvgart appears to work just as well when given every other week, broadening options for personalized treatment.
What is Generalized Myasthenia Gravis (gMG)?
Generalized myasthenia gravis (gMG) is a rare autoimmune disorder that affects the skeletal muscles, causing muscle weakness and fatigue. The condition is caused by the production of self-reactive antibodies against proteins on the surface of nerve cells that are involved in signaling to the muscles. This leads to a breakdown in communication between the nerves and muscles, resulting in weakness and fatigue. Symptoms typically include drooping eyelids, blurred or double vision, difficulty speaking, chewing, and swallowing, and weakness in the arms and legs.
How does Vyvgart (efgartigimod alfa) work?
Argenx’s Vyvgart works by blocking a protein called neonatal Fc receptor (FcRn), which extends the time antibodies remain circulating in the bloodstream by preventing their destruction. Blocking FcRn helps clear antibodies from circulation, including the harmful ones that drive MG. Vyvgart is infused into the bloodstream once weekly over four-week cycles and is approved to treat adults who have self-reactive antibodies against the acetylcholine receptor, the most common ones found in MG patients.
What was the study about?
The researchers reviewed the medical records of 16 adults with gMG who received Vyvgart as part of an expanded access program in the Netherlands. The program gave patients access to Vyvgart before it was available on the market. The patients had been living with the disease for a median of 12 years and had received intravenous immunoglobulin and/or plasma exchange prior to receiving Vyvgart. Ath the onset of treatment, Vyvgart was infused in the hospital once weekly for four weeks. One patient only received two infusions during these first four weeks. Doctors then adjusted how often Vyvgart was given based on a patient’s symptoms, levels of circulating antibodies, and side effects.
What were the study findings?
After four weeks of treatment, nine (56.3%) patients had a favorable outcome, defined as a clinically meaningful improvement on at least two disease measures or being able to reduce or stop corticosteroids or intravenous immunoglobulin or plasma exchange, without needing rescue medications. Vyvgart also resulted in better quality of life over four weeks, as measured by a mean reduction of 5.75 points on the 15-item revised version of the MG-QoL15r questionnaire. Lower scores on the questionnaire indicate better quality of life. Most patients (80%) reduced their doses of corticosteroids or azathioprine or required fewer doses of intravenous immunoglobulin or sessions of plasma exchange. Despite more frequent dosing than in the clinical study, levels of antibodies in the patients’ blood remained stable and did not fall below safety thresholds.
Conclusion
Vyvgart appears to be an effective treatment for adults with refractory generalized myasthenia gravis (gMG). The expanded access program shows that more than half of the patients saw a clinically meaningful improvement in symptoms and better quality of life. While patients required more frequent dosing, Vyvgart appears to work just as well when given every other week, broadening options for personalized treatment. More research is needed to determine the long-term effectiveness of Vyvgart for refractory gMG.
Originally Post From https://myastheniagravisnews.com/news/more-frequent-vyvgart-dosing-may-needed-real-world-study/
Read more about this topic at
VYVGART Hytrulo (efgartigimod alfa and hyaluronidase- …
FDA Approves New Treatment for Myasthenia Gravis