A recent clinical trial has confirmed the drug Ibudilast reduces brain shrinkage in patients with progressive multiple sclerosis.
Multiple sclerosis is a condition affecting the brain and spinal cord. The disease causes the breakdown of myelin, the substance that surrounds nerve axons that carry messages to and from the brain. Myelin protects the nerves from damage and helps to ensure fast transmission of signals to and from the brain. Without the protection of myelin, nerves can become damaged, signals to and from the brain are slowed, and in some cases, those messages are distorted or do not get through.
Individuals with multiple sclerosis can have flare ups of symptoms which can disappear for weeks or even months before returning. However, there is a progressive form of the disease which causes a gradual decline in function and brain atrophy or shrinkage.
Multiple sclerosis can cause many debilitating symptoms including muscle weakness, numbness, pain, cognitive problems, balance problems, loss of sensation, vision loss, fatigue, and many more. There is no cure for multiple sclerosis, although specific symptoms can be treated and therapies have been developed that help to prevent relapses.
There are relatively few treatments available to patients with the progressive form of the disease, although one drug – Ibudilast – has shown some promise for slowing progression of the disease.
The trial was conducted on 255 patients, who were given up to 10 capsules of Ibudilast or placebos each day for 96 weeks. The rate of brain shrinkage was assessed every 6 months using MRI scans. The most common side effects were nausea, gastrointestinal problems, headaches and depression, although there was no significant difference in these adverse effects between the different groups in the study.
The results of the trial confirm that the drug can reduce brain shrinkage. A comparison between the patient groups showed Ibudilast reduced brain atrophy by 0.0009 units per year – approximately 2.5 milliliters of brain tissue. What is not known is the degree to which that loss of shrinkage has an effect on loss of function or symptoms of the disease.
“The trial’s results are very encouraging and point towards a potential new therapy to help people with progressive MS,” said Robert J. Fox, M.D, lead research for the study. “It also increased our understanding of advanced imaging techniques, so that future studies may require a smaller number of patients followed over a shorter period of time.”
The next step is to determine the extent to which the slowing of brain atrophy alleviates the symptoms of progressive multiple sclerosis.
The clinical study was funded by the National Institute of Neurological Disorders and Stroke (NINDS) and the results of the study – Phase 2 Trial of Ibudilast in Progressive Multiple Sclerosis – was recently published in the New England Journal of Medicine: DOI: 10.1056/NEJMoa1803583