How Is Myasthenia Gravis Treated?

The goal of treating myasthenia gravis (MG) is to reduce or improve muscle weakness. Some people’s symptoms can improve so they only feel weakness occasionally. Some people even go into remission. This means they have no signs or symptoms. But other people can struggle to find a treatment that works for them.¹

There are several ways to treat MG. Some of these treatments are symptomatic therapies. This means they directly target disease symptoms, such as muscle weakness, without treating the underlying disease.  Other therapies, called disease-modifying therapies, target the underlying cause of MG by calming the body’s immune system. This results in a lessening of symptoms.¹

It may take some time to find the right combination of treatments that work for you. That is because MG can be very different from person to person. Certain people with MG may need specific treatments, including:¹

• Children
• People who are pregnant
• Older adults
• People with rare subtypes of MG

Acetylcholinesterase inhibitors

Acetylcholinesterase inhibitors are a type of drug that improves nerve signals to the muscles. This symptomatic therapy works for MG by making the signals from your nerves to your muscles last longer. Pyridostigmine (Mestinon^®) is the drug usually recommended for people with MG.^1,2

Steroids and other immunosuppressants

Steroids are drugs that help calm an overactive immune system. Steroids are also called corticosteroids. Your doctor may prescribe them if your muscle weakness does not get better after taking acetylcholinesterase inhibitors.¹

Some people cannot take steroids or need an additional drug to calm their immune system (immunosuppressant). But chronic use of high-dose steroids can cause side effects like weak bones (osteoporosis), high blood sugar, stomach ulcers, and increased risk of infection. If steroid use is not right for you, your doctor can prescribe other drugs that suppress the immune system, such as:¹

• Azathioprine (Azasan^®, Imuran^®)
• Cyclosporine (Gengraf^®, Neoral^®, Sandimmune^®)
• Methotrexate (Rheumatrex^®, Trexall^®)
• Mycophenolate mofetil (CellCept^®, Myfortic^®)
• Tacrolimus (Astagraf^® XL, Envarsus^® XR, Prograf^®)

Plasma exchange

Plasma is one of the building blocks of blood. Plasma carries antibodies, which are chemicals the body makes to fight germs. In an autoimmune condition like MG, some antibodies incorrectly attack healthy tissue. Plasma exchange (plasmapheresis) is a process in which a machine circulates your blood. The machine removes excess antibodies and replaces them with healthy plasma.¹

Plasma exchange is most often used when symptoms are temporarily severe, sometimes called a flare. It can also be used on a regular basis for serious MG or MG not responding to other treatments. Plasma exchange starts to work in days, but the effects are temporary.¹

Intravenous immunoglobulin (IVIG)

IVIG is an injection into your veins. The injection contains healthy antibodies. IVIG is most often given during a flare. It helps reduce the body’s attack on the nervous system. IVIG may be used on a regular basis for more serious MG. Like plasmapheresis, it begins working in days and brings temporary relief for a few weeks.¹

Thymectomy

Thymectomy is a surgery to remove the thymus gland. Thymectomy is always recommended for people with thymoma. A thymoma is a tumor on the thymus gland. But this surgery is not an option for everyone with MG.¹

A thymectomy can help reduce symptoms and the need for immunosuppressant drugs. Sometimes it is also an option for people with MG who do not have a thymoma.¹

Lifestyle and alternative treatments

Diet, exercise, rest, and stress reduction can all help manage MG. Knowing your triggers can also help reduce flares. Some very serious, well-studied triggers include:³

• Illnesses like flu, cold, surgery, and heart or kidney problems.
• Taking certain over-the-counter or prescription drugs, especially certain antibiotics.

Other triggers for MG symptoms include:³

• Drinking alcohol
• Stress
• Foods that require a lot of chewing
• Forgetting to take your MG drugs
• Hot foods
• Large meals
• Too much exercise, or "powering through" when you are tired
• Warm weather

Antibody-based biologics

About 1 out of 10 people with generalized MG develop refractory MG. Refractory MG is a serious condition in which symptoms do not improve after other treatments. In these cases, doctors may prescribe a biologic treatment. Biologics are a type of drug made from living organisms.^5-11

All of the lab-made biologic drugs used for MG are therapeutic antibodies designed to calm the immune system. Antibody-based biologics for MG include:^5-11

• Eculizumab (Soliris^®) and efgartigimod (Vyvgart^®) can treat refractory MG with anti-acetylcholine receptor (AChR) antibodies.
• Rituximab (Rituxan^®) can treat refractory MG with anti-muscle-specific kinase (MuSK) antibodies.
• Efgartigimod alfa and hyaluronidase-qvfc (Vyvgart^® Hytrulo) can treat people with generalized MG (gMG) with anti-AChR antibodies.
• Rozanolixizumab-noli (Rystiggo^®) can treat people with generalized MG (gMG) with anti-AChR or anti-MuSK antibodies.
• Ravulizumab-cwvz (Ultomiris^®) can treat adults with generalized MG (gMG) who have anti-AChR antibodies.
• Zilucoplan (Zilbrysq^®) is used to treat generalized myasthenia gravis (gMG) in adults who are anti-acetylcholine receptor (AChR) antibody-positive.

Soliris, Ultomiris, and Zilbrysq inhibit the C5 complement protein. By inhibiting the C5 protein, they regulate part of your immune system called the complement cascade. When the complement cascade is triggered by antibodies that target your own body – as it is in generalized MG – it can cause damage to your own cells and tissues.^5-7,10,11

Soliris, Ultomiris, and Zilbrysq have a boxed warning, the strictest warning from the US Food and Drug Administration (FDA). The warnings are similar. People treated with these drugs have developed life-threatening infections including meningitis. Meningitis is a bacterial infection of the brain and spinal cord. It can be deadly if it is not quickly spotted and treated. For people taking these drugs, you may need to receive certain vaccinations to prevent infections.^12,13

It is recommended to get a meningococcal vaccine at least 2 weeks before your first dose of Soliris, Ultomiris, or Zilbrysq. You should get regular booster shots. Your doctor may also recommend antibiotics to avoid meningococcal disease.^12,13

These are not all the possible side effects of these drugs. Talk to your doctor about what to expect when taking these drugs. You should also call your doctor if you have any changes that concern you when taking these biologics.