November 2, 2021

New Infusion Therapies for Myasthenia Gravis – SOLIRIS

Specialty Infusion Blog Derick

Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disorder that causes weakness in the eyeballs and eyelids and progresses to the head, neck, limb, and respiratory muscles. Communication impairment between nerve cells and muscles prevents muscle contractions from occurring, resulting in muscle weakness.

According to the Myasthenia Gravis Foundation of America, MG is relatively rare, affecting only between 14 and 20 out of every 100,000 people in the United States. However, it’s the most common primary disorder of neuromuscular transmission. 

While there is no cure for MG, a few different treatment options are available. Rituximab (Rituxan) is an infusion therapy prescribed for patients who don’t respond to other treatments. However, a newer IV treatment with monoclonal antibodies, Soliris (eculizumab), has become the first antibody-based complement inhibitor approved in the U.S., Europe, and Japan to treat adults suffering from generalized MG.

What are the symptoms of Myasthenia Gravis?

The main symptom of MG is weakness in the skeletal muscles (muscles under your control) which occurs due to the muscles not contracting normally. When the body’s muscles fail to contract, they can’t respond to nerve impulses leading to blocked communication between the nerve and muscle.

Weakness from MG typically gets worse when the body is more active and improves with rest. Other symptoms of MG include:

  • trouble talking/hoarse voice
  • problems walking up the stairs or lifting objects
  • facial paralysis
  • difficulty breathing due to muscle weakness
  • difficulty swallowing/chewing
  • fatigue
  • drooping of eyelids
  • double vision

MG is a unique disease as not everyone will experience every symptom, and muscle weakness can change from day to day for each patient. Symptoms will most likely get more severe over time if left untreated. 

What causes Myasthenia Gravis?

There are two leading causes of MG. Many people with MG have antibodies which instead of  helping to fight off infections, viruses, and other threats to the body, mistakenly destroy, damage, or block acetylcholine receptors. Fewer receptors result in the muscles becoming weaker due to not contracting correctly.

In some cases, the immune system attacks other proteins, such as muscle-specific kinase, which is essential for helping to maintain the function of the neuromuscular junction.

While the specific cause of the abnormal autoimmune response is unknown, researchers believe that the thymus gland may help trigger or support the production of the harmful antibodies that interrupt nerve-muscle communication.

How Soliris works

By binding to the C5 protein, Soliris works by blocking and preventing the generation of the terminal complement cascade (TCC), a part of the immune system that consists of a series of reactions that trigger the adverse immune response

Possible side effects of Soliris

As with any medication, there is a risk of side effects when taking Soliris. Common side effects include:

  • headache
  • tiredness/fatigue
  • nausea
  • vomiting
  • diarrhea
  • muscle pain
  • back pain
  • cold symptoms (stuffy nose, sneezing, or sore throat)

Although rare, serious side effects may occur. You should reach out to your doctor if you experience:

  • signs of infection (fever, persistent cough or sore throat, painful or frequent urination),
  • muscle cramps
  • swelling hands/ankles/feet,
  • fast heartbeat
  • changes in the amount of urine output

Soliris is administered through an infusion, so you should let your doctor or nurse know if you experience the following symptoms during your treatment:

  • chest pain
  • trouble breathing/shortness of breath
  • swelling of your face, tongue, or throat
  • feeling faint or like you may pass out

Soliris in clinical trials

Clinical trials of Soliris were done on adult MG patients who had two or more failed immunosuppressive treatments over 12 months and continued to suffer from significant unresolved disease symptoms. 

Patients taking Soliris reported a 60% improvement in their quality of life. They also showed decreased symptoms, including improvement in their double vision, drooping of the eyelids, swallowing, speech, breathing, and muscle weakness. 

Final thoughts

While Soliris is not a cure for those living with MG, it has shown significant improvements in supporting improved functionality of MG patients as well as helping to treat and manage their symptoms that had not previously shown improvement with the use of previous treatments or  medications. 

Living with MG requires an individualized treatment plan that often includes medication, diet and lifestyle changes, and mental health care. Specialty Infusion Centers collaborate with your specialist to provide infusion therapy for MG based on your predetermined treatment plan. Our centers offer private suites, amenities, and flexible evening and weekend appointments. All you have to focus on is feeling better! Reach out to us to learn more or get started today.