Glossary

Antibody: A protein that is part of the immune system. When acting normally, antibodies protect you by attacking foreign substances, such as bacteria and viruses.

Autoimmune disease: Conditions where the immune system mistakenly attacks the body’s healthy cells, tissues, and structures.

Chronic: Long-lasting, persistent, or constant. A chronic disease is one with symptoms that occur over a long period of time. People with MG or gMG often experience both chronic and acute symptoms.

Complement proteins: Proteins that are released by the complement system to enhance (complement) the ability of your immune cells to do their jobs in protecting you against disease.

Complement system: Part of your immune system that enhances (complements) the ability of your immune cells to do their jobs in protecting you against disease.

Generalized myasthenia gravis (gMG): A chronic autoimmune, neuromuscular disease that causes weakness in the skeletal muscles, which can worsen after periods of activity and improve after periods of rest. This weakness can affect moving, eating, and breathing.

Immune system: A system that protects your body from foreign invaders by producing a response to fight infections and other threats.

Meningococcal infection: An infection of the lining of the brain and spinal cord and bloodstream caused by bacteria called Neisseria meningitidis. Meningococcal infections may become life-threatening or fatal if not recognized and treated early.

The Myasthenia Gravis Activities of Daily Living (MG-ADL) scale: An 8-category questionnaire that measures how much gMG symptoms affect certain functional activities of daily living, including breathing, talking, chewing, swallowing, actions such as brushing teeth and rising from a chair, as well as double vision and eyelid droop. The score ranges from 0 to 24; a higher MG-ADL score means more severe MG symptoms.

Neuromuscular junction (NMJ): The space where nerves and muscles meet. When the NMJ is damaged or signals between nerve and muscle in the NMJ are interrupted, muscles can grow weaker.

Neurotransmitter: A chemical messenger that carries information from nerve cells, across a space, to other cells. Neurotransmitters help you control your muscles, feel sensations, and respond to your environment.

Receptors: Proteins inside cells, or on their surface, that receive chemical signals.

Risk Evaluation and Mitigation Strategy (REMS): A drug safety program that the U.S. Food and Drug Administration (FDA) can require for certain medications to help reduce the occurrence or severity of a particular serious adverse event. They help support a drug’s safe use as described in the product’s FDA-approved prescribing information.