A drug currently being developed for people suffering from multiple sclerosis (MS) has shown promising results to stop the progression of the disease in mice. Known as laquinimod, it is being tested phase 3 clinical trials, but the way it works on the human body is still not very well understood.
So far, no treatment is known to cure MS, and the disease is only controlled with medication which modifies the disease or addresses its symptoms – so there are high hopes regarding laquinimod.
In this study, published in the journal Neurology: Neuroimmunology & Neuroinflammation, researchers investigated the effects of laquinimod on immune cells, which are dysfunctional in patients with MS.
Their work confirms previous evidence that the drug can act by changing the behaviour of immune cells and preventing them from entering the brain and spinal cord.
Impact on cell clusters
The scientists, from the University of California-San Francisco, worked with mice models of MS, giving the rodents either a placebo or oral laquinimod. The results were significant: 29% of the mice that received the drug developed MS vs 58% of those on the placebo. A reduction in harmful clusters of B cells, which play a key role in the development of primary progressive MS (see box) was also observed when the animals had been given laquinimod.
Furthermore, they carried out an experiment on mice that had began to develop paralysis, and observed that the progression of the disease was slowed down after taking the medicine. The scientists also noted a reduction in dendritic cells that help create specialised T cells which contribute to the disease – in T cells and in harmful antibodies.
These findings contribute to the understanding of how the drug actually works on the immune system and how it could help people with MS both primary progressive and relapsing-remitting. More work during clinical trials will surely reveal whether similar effects can be expected in humans.