Amyotrophic Lateral Sclerosis (ALS)
Amyotrophic Lateral Sclerosis (ALS), also known as "Lou Gehrig's disease," is a progressive neurodegenerative disease that inhibits an individual's ability to control voluntary muscle movement. Affecting the brain and spinal cord's role in the initiation and control of muscle movement, ALS ultimately leads to paralysis and eventually death. There are approximately 30,000 individuals suffering from ALS in the United States at any one time.
- While there is no known cure for ALS, treatment of the disease is focused on relieving symptoms, preventing complications, and maximizing the quality of life. Presently, the only pharmaceutical available to treat the symptoms of ALS is Rilutek®. The drug has been demonstrated to increase life expectancy for patients with ALS by a few months.
- Avicena, in collaboration with Dr. Jeffrey Rosenfeld of the Carolinas ALS Center, is presently developing two novel drug candidates for the treatment of ALS. ALS-02, granted orphan drug designation by the FDA, recently completed its first Phase III trial. Data from this trial, when combined with a second trial of ALS-02, demonstrated a positive trend toward decreased mortality. Dr. Jeffrey Rosenfeld of the Carolinas ALS Center is presently analyzing additional data points. Upon completion, Avicena intends to discuss the findings with the FDA to help determine appropriate next steps.
- In preclinical studies, both of the company's compounds have demonstrated significant neuroprotective effects that have led to increased survival rate, improved motor performance and delayed onset of disease.
What is ALS
ALS is a neurodegenerative disease that attacks the motor neurons of the brain and spinal cord that are responsible for voluntary muscle movement. As these motor neurons degenerate, their ability to send impulses to the muscle fibers is compromised. The progressive degeneration of the motor neurons eventually leads to their death, resulting in the brain's inability to initiate or control muscle movement. Once a patient's muscles no longer receive the messages that they require to function, they begin to atrophy.
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Types of ALS
ALS is classified into two types. The most common type is known as "sporadic ALS" since it may occur without any prior family history of the disease. Sporadic ALS accounts for approximately 85% to 90% of all cases.
The second type, which accounts for the remaining 10% to 15% of patients, is referred to as "familial ALS." This type of ALS occurs more than once in a family lineage and is the result of genetic inheritance.
Despite their differences, sporadic and familial ALS are both marked by a similar set of symptoms, as well as disease progression.
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Symptoms of ALS
It is important to note that initial symptoms of ALS may vary greatly form patient to patient. Initial symptoms include increasing muscle weakness and muscle twitching, particularly in the hands, arms and/or legs. This can often result in tripping, stumbling, or falling. In advanced stages of ALS, patients may experience slurred speech and difficulty swallowing or breathing.
As ALS only attacks voluntary motor neurons, the five senses (sight, touch, hearing, taste and smell) are not impaired. Additionally, despite the degenerating condition of the body, the mind is generally not affected and remains alert throughout the progression of the disease.
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Progression of ALS
There is often a dramatic difference in the manner and rate at which ALS progresses from patient to patient. While one person may initially experience difficulty walking, another may first suffer from slurred speech. Furthermore, one patient may experience severe symptoms very quickly while another may have relatively mild symptoms for an extended period of time.
In general, a patient's hands and feet are affected first, causing difficulty in walking, lifting, dressing or washing. This weakening then spreads throughout the body at differing rates and eventually impacts a patient's ability to speak, eat and breathe. Difficulty with breathing often causes a patient to require the support of a ventilator and late stages of ALS can lead to muscle paralysis.
While the mean survival time with ALS is three to five years, many people live for longer periods of time following diagnosis. It is not unusual for patients to live for 10 to 20 years with the disease. In fact, in a small number of patients, ALS is known to halt its progression or even remit.
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Diagnosis of ALS
Diagnosing ALS is often difficult and relies on a series of tests designed to rule out diseases that demonstrate symptoms similar to ALS. Presently, there is no single test or test procedure used to diagnose the disease.
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Causes of ALS
While medical researchers have not yet been able to pinpoint the cause of ALS, there are several biological mechanisms that are generally believed to play a role in the disease. These include:
- damaging impact of free radicals on the body
- over stimulation of motor neurons
- mitochondrial dysfunction
Additionally, there are several research studies underway that are investigating potential genetic and/or environmental risk factors that may contribute to or cause ALS.
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Incidences of ALS
With an incidence rate of approximately 1 in 10,000, ALS affects roughly 30,000 Americans at any one time. Each year, approximately 5,600 new cases of ALS are diagnosed with the majority of patients classified as Caucasian (93%) and male (60%). The average age at the time of diagnosis with ALS is 55 with most people falling between the ages of 40 and 75.
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Treatment of ALS
While there is no known cure for ALS, treatment of the disease is focused on relieving symptoms, preventing complications, and maximizing the quality of life.
Presently, the only pharmaceutical available to treat the symptoms of ALS is Aventis' RilutekŪ. The drug has been demonstrated to increase life expectancy for patients with ALS by a few months.
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