Charcot-Marie-Tooth Disease
Also known as: CMT, Hereditary Motor and Sensory Neuropathy, Peroneal Muscular Atrophy
Charcot-Marie-Tooth disease (CMT) is a group of inherited disorders that affect the peripheral nerves. These nerves carry signals from the brain and spinal cord to the muscles and sensory receptors throughout the body. CMT primarily affects the nerves in the arms and legs, leading to muscle weakness, atrophy, and sensory loss. Symptoms typically begin in adolescence or early adulthood, but can appear at any age. CMT is a progressive disease, meaning symptoms worsen over time, but most individuals with CMT have a normal life expectancy.
Imagine your body has wires (nerves) that help your muscles move and feel things. In CMT, some of these wires are damaged, especially in your legs and feet. This makes it hard to walk and you might not feel things as well. It's like having a weak signal on your phone, making it hard to hear the other person.
Signs & Symptoms
- Muscle weakness in feet and legs
- Foot deformities (high arches, hammertoes)
- Decreased sensation in feet and legs
- Loss of muscle bulk in lower legs (stork leg deformity)
- Difficulty with balance and walking
- Hand weakness and clumsiness
- Fatigue
- Pain (sometimes)
- Scoliosis (in some cases)
Treatment Options
Physical Therapy
SUPPORTIVEOccupational Therapy
SUPPORTIVEOrthotics (ankle-foot orthoses)
SUPPORTIVEPain Management (medications, therapies)
MODERATELY EFFECTIVESurgery (for foot deformities or scoliosis)
MODERATELY EFFECTIVEPXT3003 (baclofen, naltrexone, and D-sorbitol)
MODERATELY EFFECTIVEDiagnosis
- Neurological examination
- Nerve conduction studies
- Electromyography (EMG)
- Genetic testing
- Nerve biopsy (rarely)
History
Charcot-Marie-Tooth disease was first described in 1886 by Jean-Martin Charcot, Pierre Marie, and Howard Henry Tooth, who independently reported the condition.
Recent Breakthroughs
Gene Therapy Advances for CMT1A
Preclinical studies have shown promising results for gene therapy approaches targeting the PMP22 gene in CMT1A, the most common form of CMT. Adeno-associated virus (AAV) vectors are being investigated to deliver functional copies of the gene or to silence the overexpressed PMP22 gene.
PXT3003 Phase 3 Trial Results
Phase 3 clinical trial results for PXT3003, a combination of baclofen, naltrexone, and D-sorbitol, showed potential benefits in slowing disease progression in CMT1A patients. Further studies are underway to confirm these findings and assess long-term efficacy.