Managing gMG

Management strategies for myasthenia gravis (MG) aim at restoring the patients’ muscle strength and well-being by controlling the disease and its symptoms, while reducing potential medication side effects.1,2

After receiving any treatment for MG, patients can expect an evaluation of their symptoms and muscle weakness along with monitoring of potential medication side effects over time.1–3

Depending on the treatment, patients may need to wait for variable periods of time before an evaluation of the treatment effect is possible.1,4

The treatment approach for each patient with MG may differ depending on their individual situation and preferences and the judgement made by their healthcare professionals.1,3 Several treatment options are available to manage MG, including so-called symptomatic therapies, long-term and short-term immunosuppressive therapies, surgery and new therapies.1,4 A number of these treatments are commonly used in clinical practice without being specifically approved for MG (so called "off-label" use).2,5
Most – but not all – patients with MG may receive symptomatic therapy with drugs called acetylcholinesterase inhibitors as part of their initial treatment.1,3 Acetylcholinesterase inhibitors can control symptoms of muscle weakness,5 as they act to improve the communication between nerves and muscles by increasing the amount of a chemical called acetylcholine in the body.4 Acetylcholinesterase inhibitors are most commonly administered as oral tablets in adult patients with MG, though administration in the form of a syrup or as an injection is also possible.2,6 The dose is adjusted to suit each patient’s needs, aiming to maximise benefit while minimising side effects.3,7 A therapeutic effect from acetylcholinesterase inhibitors may be seen within a few hours after administration.4
Immunosuppressive therapies aim at suppressing the abnormal activity of the immune system that is seen in patients with MG.1,4 Immunosuppressive therapies used in MG can be grouped into long-term and short-term depending on whether they are administered for a relatively long or a relatively short period.4
When symptomatic therapy does not adequately control the symptoms of a patient with MG, long-term immunosuppressive therapy may be used.1,3 Long-term immunosuppressive therapy can include steroids and/or non-steroidal immunosuppressive drugs.1,3,4

Steroids, also known as corticosteroids, are usually administered orally in patients with MG, though other ways of administration are possible such as infusion into a vein.1,2,5,8 The dose and duration of administration are adjusted depending on the severity of the disease, individual patient factors and side effects.1,2 A therapeutic effect from steroids may be seen within a few weeks after administration.1 When taking steroids for long periods, side effects such as problems with the bones or skin, weight gain or increased risk of infections may be experienced by some patients.1 The number and severity of side effects differ among patients and depend on the steroid dose and duration of use.8

Non-steroidal immunosuppressive drugs can be used together with steroids or taken alone when steroid use is not possible.1,3,5 The type, route of administration, dose and duration of treatment with non-steroidal immunosuppressive drugs in patients with MG is decided by healthcare professionals on a case-by-case basis.1,3,5 The time period for seeing a therapeutic effect from non-steroidal immunosuppressive drugs may vary between months and years after administration depending on the chosen drug.1,5

Some patients with MG may receive short-term immunosuppressive therapies.1,3 This can be, for example, the case in patients who need a treatment with a rapid effect such as patients with severe symptoms or who experience a life-threatening condition due to MG, in patients who are in preparation for surgeries or in patients who are about to start treatment with steroids and potential worsening of symptoms needs to be prevented.1,3 Two commonly used short-term immunosuppressive therapies are the so-called plasma exchange and intravenous immunoglobulin.1,3 It should be noted that these therapies may also be used as long-term treatment in some patients.1,3

Plasma exchange (sometimes called plasmapheresis) is a therapeutic procedure used to remove abnormal components such as antibodies and proteins from the patient’s blood.1,9 In preparation for plasma exchange, a needle is usually inserted into a vein in each of the patient’s arms.9 The patient may then rest on a reclining chair or bed while a machine draws blood from one arm, exchanges it and returns it to the other arm, using replacement plasma – the liquid component of the blood.9,10 The procedure may last several hours9 and may be repeated for several cycles on different days.10

Intravenous immunoglobulin refers to a solution containing antibodies (immunoglobulins) collected from many healthy donors.8 It is injected into a vein in the arm using an infusion pump.11 The dose and duration of the infusion is individualised for each patient and may be repeated for several cycles on different days.8,11

In some patients with MG, surgery may be recommended to remove an organ called the thymus (or thymus gland) that is located in the chest.1–3,12 This type of surgery is known as thymectomy.1–3,12Minimally invasive surgical procedures for thymectomy are increasingly employed in patients with MG, involving very small cuts (incisions) to access the thymus using specialised tools and robotic systems.1,12,13
A few new therapies have been recently approved for MG while several others are under development, all aiming to address various aspects of the mechanisms involved in the development of the disease1,5 and reduce side effects related to conventional treatments.14,15 Some of these therapies belong to a drug class called biologics,1,5 which refers to pharmaceutical products that are isolated from natural resources (human, animal or microorganism) and may be produced by biotechnology methods or other cutting-edge technologies.16
Please consult your treating physician or healthcare team for more information or if you have questions about your therapy.
MG, myasthenia gravis.
Gilhus NE, et al. Myasthenia gravis. Nat Rev Dis Primers. 2019;5(1):30. Diagnostik und Therapie myasthener Syndrome. DGN. Available at: https://dgn.org/leitlinie/diagnostik-und-therapie-der-myasthenia-gravis-und-des-lambert-eaton-syndroms. Last accessed: August 2023. Sanders DB, et al. International consensus guidance for management of myasthenia gravis: Executive summary. Neurology. 2016;87(4):419–425. Jayam Trouth A, et al. Myasthenia gravis: A review. Autoimmune Dis. 2012;2012:874680. Riley TR, et al. An update of the pharmacological treatment options for generalized myasthenia gravis in adults with anti-acetylcholine receptor antibodies. Am J Health Syst Pharm. 2023:zxad035. Mantegazza R, et al. Current and emerging therapies for the treatment of myasthenia gravis. Neuropsychiatr Dis Treat. 2011;7:151–160. Meriggioli MN, Sanders DB. Autoimmune myasthenia gravis: Emerging clinical and biological heterogeneity. Lancet Neurol. 2009;8(5):475–490. Melzer N, et al. Clinical features, pathogenesis, and treatment of myasthenia gravis: A supplement to the Guidelines of the German Neurological Society. J Neurol. 2016;263(8):1473–1494. Therapeutic apheresis services. Patient information leaflet – Plasma exchange procedure. NHS Blood and Transplant. Available at: https://nhsbtdbe.blob.core.windows.net/umbraco-assets-corp/1948/plasma-exchange-procedure.pdf. Last accessed: August 2023. Menon D, Bril V. Pharmacotherapy of generalized myasthenia gravis with special emphasis on newer biologicals. Drugs. 2022;82:865. Intravenous immunoglobulin (IVIg) in the treatment of acute and chronic neurological diseases. NHS. The Walton centre. NHS Foundation Trust. Available at: https://www.thewaltoncentre.nhs.uk/patient-leaflets/intravenous-immunoglobulin-ivig-in-the-treatment-of-acute-and-chronic-neurological-diseases/483784. Last accessed: August 2023. Narayanaswami P, et al. International consensus guidance for management of myasthenia gravis: 2020 update. Neurology. 2021;96(3):114–122. Myasthenia gravis. Treatment. NHS. Available at: https://www.nhs.uk/conditions/myasthenia-gravis/treatment/. Last accessed: August 2023. Kaminski HJ, Denk J. Corticosteroid treatment-resistance in myasthenia gravis. Front Neurol. 2022;13:886625. Murai H, et al. The Japanese clinical guidelines 2022 for myasthenia gravis and Lambert–Eaton myasthenic syndrome. Clin Exp Neuroimmunol. 2023;14:19–27. What Are "Biologics" Questions and Answers. FDA. Available at: https://www.fda.gov/about-fda/center-biologics-evaluation-and-research-cber/what-are-biologics-questions-and-answers. Last accessed: August 2023.