A recent study – which you can find in the journal Muscle & Nerve – investigated Soliris as a treatment for anti-acetylcholine receptor (AChR) antibody-positive generalized myasthenia gravis (gMG). It returned with positive results regarding safety and efficacy, which is very exciting for patients and doctors alike.
About Myasthenia Gravis
Before we dive into Soliris and the corresponding research, we should first gain an understanding of what this rare disease is. Myasthenia gravis (MG) is the most common autoimmune neuromuscular disorder. Those affected experience weakness in the voluntarily controlled muscles. Throughout the world, about 20 of every 100,000 people have MG. It is an autoimmune condition, meaning the body attacks itself, specifically the proteins necessary for communication between the brain and muscles. This causes symptoms like drooping eyelids, issues with chewing and swallowing, fatigue and weakness in the skeletal muscles, slurred speech, double vision, and a changed gait. Physical activity worsens the symptoms, whereas periods of rest can improve them. For a small percentage of those with MG, weakness in the chest could lead to life-threatening respiratory issues.
Doctors diagnose this condition through a physical exam, evaluation of patient history, blood tests, and EMGs. Like many rare disorders, a diagnosis is not always easy to obtain. The similarity of symptoms to other conditions often results in a misdiagnosis. After doctors have confirmed that one has MG, treatment consists of steroids, plasmapheresis, or surgery to remove the thymus gland. While there is no cure, some medications can significantly improve symptoms or even induce remission.
Titled “Safety and outcomes of eculizumab for acetylcholine receptor positive generalized myasthenia gravis in clinical practice,” this study looked at Soliris for gMG, which is also known under the generic name eculizumab. This treatment has already received approval in Japan and the United States, which actually hinged on data from another trial: the REGAIN study, alongside its open-label extension (OLE) portion. The studies shared a few commonalities, namely a demonstration of clinically meaningful benefits, such as quality of life, functional ability, activities of daily living, and boosted muscle strength.
Now, the latest study looked at 12 AChR antibody-positive gMG patients from two Boston hospitals: Mass General and Brigham and Women’s. All of these patients had been treated with at least one dose of Soliris before being followed for an average of 18 months. Additionally, patients had also failed to respond to prior treatments – the majority were on standard therapies (prednisone, Mestinon, etc) or maintenance therapies (IVIG, plasma exchange, etc) when starting the trial.
In order to evaluate the data being compiled, researchers used the MG Foundation of America Post-intervention Status (MGFA-PIS) while also looking at adverse events (AEs), MG-Activities of Daily Living (MG-ADL), Soliris’ effect on clinical classification (MGFA-CC), and whether or not additional immunomodulatory therapies are needed.
- Increases in MGFA-CC and MGFA-PIS scores were seen in at least 80% of patients after about one month
- MG-ADL scores – which have to do with the ability to perform daily activities – decreased from 8.7 to 2.8
- Higher scores relate to a higher level of disability
- This score remained below 3.5 for more than one and a half years
- Over the course of about 18 months, there was a decrease in treatment with prednisone, although it is important to note that no patient discontinued completely
- The average prednisone dose dropped from 22.5 to 7.2 mg
- All five patients who were initially being treated with IVIG stopped treatment
- Two returned to maintenance therapy after one year in regard to little improvement in a clinical sense
- Patients undergoing plasma exchange were able to stop this treatment without any signs of worsening disease
- Adverse events were mild and did not lead to any discontinuation of the study drug
Overall, these results show that Soliris is both efficacious and safe for gMG patients. You can read more about this research and what it means at Myasthenia Gravis News.