A DNA vaccine is showing promise as a novel treatment for multiple sclerosis (MS), say North American scientists.

Findings from a study of 30 patients with MS showed that intramuscular injections of the vaccine were well tolerated and led to beneficial changes to the immune system.

The cause of MS is unknown, but pathology is thought to involve immune attack of myelin sheaths surrounding neurons. The latest study involved a DNA vaccine that encodes the full length of the myelin basic protein.

Patients with relapsing–remitting or secondary progressive MS were randomly assigned to receive the vaccine, named BHT-3009, or placebo. Intramuscular injections were given at one, three, five and nine weeks.

After 13 weeks, patients given placebo were given four injections of BHT-3009.

Regular assessments, including MRI, were carried out from the beginning of the study until 50-week follow-up.

The researchers found the vaccine had favourable trends on MRI, with a trend towards decreased number and volume of brain lesions in those given BHT-3009, compared with placebo.

Additionally, the blood and cerebrospinal fluid of three patients showed the vaccine led to a reduction in the number of interferon-[gamma] CD4+ cells targeting the myelin basic protein.

The researchers have already started a phase IIb trial into the vaccine involving 290 patients.

Professor Alan Thompson, an expert in clinical neurology at University College London, said: ‘It’s clearly well tolerated and it needs more study.

‘It’s just one of several different options including reducing inflammation, neuroprotection and repair.’

Comment below and tell us what you think