ALS: Current Treatments and Prevention Strategies for Longevity - Rare Disease

Dr. Chen Shunsheng reply Rare Disease

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Many neuromuscular diseases cause progressive muscle atrophy, including progressive muscular atrophy, spinal muscular atrophy, and motor neuron diseases, among others.
Among these, motor neuron diseases progress the fastest.
Motor neuron disease refers to the progressive degeneration of motor neurons in the spinal cord, brainstem, and motor cortex, leading to progressive weakness and atrophy of the limbs, respiratory muscles, and muscles involved in swallowing or tongue movement.
Clinically, varying degrees of muscle weakness, atrophy, and signs of upper motor neuron involvement can be observed.
The time from diagnosis to death is approximately three to four years, with death often attributed to respiratory failure or respiratory tract infections resulting from muscle atrophy.
Motor neuron disease is also known as amyotrophic lateral sclerosis (ALS) based on the location of the lesions.
Other neurological diseases, such as Parkinson's disease, brainstem stroke, cervical and lumbar spinal stenosis, cervical myelopathy, brachial plexus lesions, and other neuropathies, are often misdiagnosed as this condition, necessitating thorough differential diagnosis before establishing a diagnosis.
Common tests performed before confirming a diagnosis of motor neuron disease include electromyography, nerve conduction studies, magnetic resonance imaging (MRI) of the head and neck, muscle biopsy, blood tests, urinalysis, and cerebrospinal fluid analysis.
Treatment methods for motor neuron disease can be divided into two categories: (1) disease-specific treatments and (2) patient-centered treatments.
The latter focuses on alleviating the suffering and discomfort caused by various complications experienced by the patient, typically through symptomatic therapy.
In the past, there were no effective medications for motor neuron disease, but in the last two to three years, several drugs have been developed, categorized based on research phases and effectiveness: (1) proven effective treatments: Riluzole is the only drug approved by the U.S.
Food and Drug Administration (FDA) for motor neuron disease, marketed under the brand name Rilutek.
(2) Potentially effective treatments that have completed Phase III clinical trials but are not yet FDA-approved; (3) treatments evaluated in clinical trials with a lower likelihood of effectiveness.
We will first discuss the first two categories.
Riluzole has been proven effective for this condition.
Its mechanism of action involves blocking the toxicity of glutamic acid in motor neurons, thereby preventing damage to motor neurons associated with this disease.
Patients taking Riluzole experience a slower progression of the disease, which not only delays the need for tracheostomy and the onset of respiratory failure but also improves quality of life and makes caregiving easier.
Although average life expectancy still requires further improvement, multiple follow-up studies have shown that Riluzole does not have significant severe side effects or cases leading to adverse complications, making it the only drug objectively proven to extend life for patients with motor neuron disease.
Other potentially effective treatments include several drugs that may also have therapeutic effects on motor neuron disease, among which insulin-like growth factor (IGF-1) and brain-derived neurotrophic factor (BDNF) show more definitive efficacy.
Both are growth factors, expected to promote nerve regeneration to achieve therapeutic effects.
IGF-1 has passed Phase III trials, while the results of BDNF's Phase III testing are still pending evaluation.
Additionally, some other drugs may be worth trying, including: (1) Vitamin E and other antioxidants, as clinical observations have found that some familial forms of motor neuron disease exhibit defects in the peroxidase gene on chromosome 21, leading to insufficient enzyme function that normally clears free radicals; supplementing with Vitamin E or other antioxidants may be beneficial.
(2) Glia-derived neurotrophic factor (GDNF) and other growth factors, such as NT-3/4 or Axokine, have been found in laboratory studies to promote nerve regeneration, but their efficacy in humans remains uncertain.
(3) Glutamate antagonists.
In summary, motor neuron disease, which previously left the medical community at a loss, can now extend patients' lives with Riluzole treatment, along with several new drugs and therapies on the horizon, providing greater assurance for patients' lives and quality of life.
Early diagnosis and treatment may further enhance outcomes.

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Reply Date: 2004/08/16