Older rheumatoid arthritis drug is more effective against MS than newer, costlier drug

Mabthera, when used outside the intended indications, rheumatoid arthritis and lymphoma, is more effective than one of the more recent drugs for multiple sclerosis. This according to an observation study by researchers from Sweden´s Karolinska Institutet, which is in published in Annals of Neurology.

Increasingly efficacious disease modulatory drugs have been developed in recent years against multiple sclerosis (MS) but some of them carry risks of adverse reactions, which limits their usefulness. Tysabri (natalizumab), which is considered one of the most powerful of today's MS drugs, in about 50 per cent of patients is associated with a greatly increased risk of contracting an opportunistic, potentially fatal viral infection of the brain. A simple blood test is all it takes to assess if someone is at risk of infection. Consequently, patients who have responded well to Tysabri often switch regimens to minimise the risk of this serous side-effect. However, when patients are taken off Tysabri, there is a high chance that their MS will flare up despite the change-over to another MS drug.

Compared outcomes

In this present observation study, which was conducted in Sweden at the MS clinics at Karolinska University Hospital, Sahlgrenska University Hospital and Umeå University Hospital, researchers compared the outcomes for a total of 256 patients who had switched from Tysabri to either Gilenya or Mabthera.

"We found that patients treated with Mabthera ran a much lower risk of their MS flaring up after the change of drugs than those treated with Gilenya," says principal investigator Fredrik Piehl, professor at Karolinska Institutet's of Department of Clinical Neuroscience and consultant at Karolinska University Hospital's neurology clinic. "Those who changed to Mabthera also had a lower risk of developing an adverse reaction to the new drug."

Older drug

Mabthera is an older drug mainly used for the treatment of rheumatoid arthritis and lymphoma, and has not been formally approved for the treatment of MS. Nonetheless, a growing number of patients in Sweden have received this treatment as many clinics have found it effective. But since there are no evaluations of its medical efficacy, its use is controversial and has been reported to the Health and Social Care Inspectorate on the grounds that there is no evidence to support it.

"The results we've seen in this study provide strong support for the genuine efficacy of Mabthera in the treatment of high-inflammatory MS and for it being a valuable alternative to approved MS drugs for this category of patients," says Professor Piehl. "It would also bring considerable savings to the healthcare services as it is much cheaper than the regular MS drugs."