Dexpramipexole promising in phase II trial for Lou Gehrig's disease
Results of a phase II clinical trial shows the drug dexpramipexole slows the progression of amyotrophic lateral sclerosis (ALS), otherwise known as Lou Gehrig’s disease.
Currently, there are only two drugs that treat ALS. The disease progressively causes death of nerve cells in the brain and spinal cord that ultimately leads to paralysis and death from respiratory failure.
Merit Cudkowicz, MD, director of the Massachusetts General Hospital (MGH) Neurology Clinical Trials Unit and ALS Center, lead author of the study said, "We need more therapies to slow, halt and ultimately reverse the course of disease and also therapies to treat the symptoms."
The two drugs available for ALS treatment are riluzole, which extends life about 10 percent, and Nuedexta, which treats the emotional instability associated with Lou Gehrig’s disease.
Earlier this year, researchers from Northwestern University announced a breakthrough in understanding the cause of ALS, or Lou Gehrig’s disease. In all cases, the disease occurs as the result of a breakdown of protein recycling in the brain and spinal cord. The Northwestern finding should also lead to new treatments within the next 5 to 10 years.
For the trial, patients were tested in two phases. The first group of 102 patients was split into 4 groups; all had been recently diagnosed with ALS.
Patients in the study were given either and oral placebo or dexpramipexole at total daily dosages of 50, 150 or 300 mg for 12 weeks.
After 12 weeks the participants were given just placebo for four weeks; then split again into two groups and given either 50 or 300 mg of dexpramipexole for 24 weeks.
The results showed 300mg of the experimental drug slowed progression of Lou Gehrig’s 30 percent, compared to placebo. The finding was the same in the second stage of the study.
"Since individual participants could have been in different treatment groups in the first and second stages of the study, seeing the same dose-dependent differences at both stages gives us confidence in the data. In a way, this was two supportive studies in one trial design," says Cudkowicz.
The drug is now in phase III clinical trials. Dexpramipexole is licensed for development by Biogen Idec and was initially developed by Knopp Biosciences of Pittsburgh.
Dexpramipexole seems to work for treatment of Lou Gehrig’s disease by protecting mitochondria in nerve cells from becoming dysfunctional. In the phase II trial, the drug was shown to extend lifespan for patients with ALS by 30 percent.