Amyotrophic Lateral Sclerosis (ALS)

ALS is a devastating, neurodegenerative disease that results in progressive muscle weakness and paralysis due to the death of nerve cells called motor neurons in the brain and spinal cord. When motor neurons die, the brain loses its ability to send messages to initiate and control voluntary muscle movements such as speaking, walking, and breathing.1,2

While ALS can affect people of any age, race, and ethnic background, symptoms most commonly appear between 55 and 75. There is significant unmet need for people and families living with ALS, as there are currently no treatments that have been shown to stop or reverse the progression of the disease.1

The underlying cause of ALS has not been identified. However, once the disease process has begun, we know that uncontrolled activation of the complement cascade, a part of the body’s immune system, is a feature of the disease as it progresses.

Individuals with ALS have high levels of activated C3, a complement cascade protein, at the neuromuscular junction where the neurons communicate directly to muscle cells, as well as the brain and spinal cords of these patients.3,4 There have been numerous studies suggesting that the elevated level of C3 present throughout the motor system of ALS patients is likely to contribute to chronic neuroinflammation and the death of motor neurons.4,5,6

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MERIDIAN: A Phase 2, Randomized, Double-Blind, Placebo-Controlled, Multicenter Study to Evaluate the Efficacy and Safety of Pegcetacoplan in Patients With Amyotrophic Lateral Sclerosis.
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  1. National Institute of Neurological Disorders and Stroke. (2020). Amyotrophic Lateral Sclerosis Fact Sheet.
  2. ALS Association. What is ALS? Retrieved June 2020 from
  3. Sta M, et al. Neurobiol Dis. 2011;42(3):211-220.
  4. Bahia El Idrissi N, et al. J Neuroinflammation. 2016;13(1):72.
  5. Woodruff, et al., PNAS January 7, 2014;111(1):E3-E4
  6. Lee, et al J Neuroinflammation. 2018;15:171.

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