New study reveals why potential MS drug does not work

Scientists now understand why a type of drug that has been successful for other autoimmune conditions doesn’t work for people with MS.

The drug, known as a TNF blocker, is already used to treat rheumatoid arthritis and Crohn’s disease - but can make MS symptoms worse.

A study has determined that people's genes can affect how they may respond to a treatment; in the future genetics may be a factor in deciding whether or not someone should try a new treatment.

The study

A team of researchers led by Professor Lars Fugger at the University of Oxford discovered what happens inside cells when a person has a specific variation of a gene known as ‘TNFRSF1A’. This variation, linked to MS, was discovered last year through a large genetics study.

The TNFRSF1A gene produces the code for the body to make the protein TNFR1, which has a role in regulating the immune system. When a person has a specific (MS-associated) variation in this gene, the protein produced acts differently and can not, or is blocked from, carrying out its normal job.

Scientists now understand that the exact same thing happens inside cells when somebody takes a TNF blocking drug.

This explains why a TNF-blocker drug, Lenercept, tested in people with relapsing-remitting MS through a randomised, controlled clinical trial in the late 1990s, actually brought on MS symptoms like optic neuritis.

Genes and MS

There are many other genes linked to MS but more research needs to be carried out to find out what roles these genes may play in causing the condition.

Nick Rijke, Director of Policy and Research at the MS Society, said: "There are many genes associated with MS, but we know little about the role they play or the influence they have on the condition.

"This important study has shown that some of your genes can play a part in deciding whether or not you respond to a treatment. In the future this could help ensure that people with MS are offered the drug treatments that are most likely to work for them."

This study, supported in part by the MS Society, was published today in the journal Nature.