Disabling Neuromuscular Spasm and Spasticity
Disabling muscle spasm is a sudden, violent, painful contraction of muscles which may occur in either acute or chronic settings. In the acute setting, muscle injury due to trauma or overuse results in severe pain and limitation of movement for hours to days. Chronic or recurrent muscle spasm is more typically associated with serious neurological disorders such as Lou Gehrig’s disease (ALS), multiple sclerosis, stroke, spinal cord injury, and cerebral palsy. Such recurrent, painful muscle spasms often, but not always, afflict individuals with spasticity, an abnormality in muscle “tone.” Spastic limbs become stiff and rigid because their muscles fail to relax, lacking normal regulation by the damaged nervous system. Both spasticity and sudden, painful muscle spasms can occur as complications of the neurological disorders mentioned above.
Acute spasms are treated with muscle relaxants (Skelaxin, Flexeril) and other therapies. Spasticity treatment may include such medications as baclofen, diazepam, tizanidine, or clonazepam. Physical therapy regimens may include muscle stretching and range-of-motion exercises to help prevent shrinkage or shortening of muscles and to reduce the severity of symptoms. Surgery may be recommended for tendon release or to sever the nerve-muscle pathway.
While muscle relaxants and antispasmodics can make it possible for the patient to begin therapeutic exercise and rehabilitation, current medications have limited clinical utility because of central nervous system side effects, including sedation and interaction with alcohol, which can impair the ability of the patient to perform normal daily functions.
The ideal therapy for disabling muscular spasms would provide a good safety profile, an efficacious mechanism of action, and no sedation or interaction with alcohol. Avigen is working to identify and develop therapies that bring physicians and their patients closer to that ideal therapy.
To this end, Avigen is investigating the use of AV650 in both acute and chronic muscle spasms. In the acute setting, successful treatment with a safe, non-sedating drug may not only provide relief from spasms and the associated pain, but may also prevent the changes in pain-signaling pathways in the nervous system that can lead to chronic pain. In serious, irreversible neurological diseases, the use of AV650 on a long-term basis may offer both treatment and prevention of recurrent, painful muscle spasms and spasticity, leading to improved function, sleep uninterrupted by pain, and better quality of life overall.