Two Types of MS Defined

RNA patterns in MS patients help classify type of disease and define best treatment option

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Multiple sclerosis (MS) and treatment for the disease vary among the approximate 400,000 MS patients in the United States. A better classification system of the disease could enable doctors to better match patients to medication.

A recent study analyzed the content of MS patient blood samples to better understand different types of MS. From this research, two types of MS were identified.

"Discuss the best MS treatment with your doctor."

Philip De Jager, MD, PhD of the Brigham and Women’s Hospital Department of Neurology, and team extracted RNA from blood cells of 363 MS patients. The study participants included 141 MS patients who were not undergoing treatment, 128 MS patients treated with interferon beta and 94 MS patients treated with glatiramer acetate.

The blood samples of the untreated patients were collected before their first treatment or at least six week after their last treatment. The medicated patients had been treated for at least three months at the time the blood sample was collected.

Computer algorithms were used to understand the patterns within the RNA.

The patients were categorized as having MSa or MSb, depending on which set of RNA molecules were found in their blood. MSa patients had a more active disease course than MSb patients that included a higher risk for future MS relapse.

MSa patients under glateiramer acetate or interferon beta were more likely to have attacks than those not under medication.

“While disease subtypes have existed for years and have been refined repeatedly, significant variability in symptom profile remains within disease subtypes,” said Nancy D. Chiaravalloti, PhD, Director of Neuropsychology and Neuroscience Research at the Kessler Foundation.

“These findings represent significant progress towards an additional categorization of the disease process that could potentially enhance our ability to understand symptom presentation,” said Dr. Chiraravalloti.

The study has a few limitations. The study focused on the initial phases of MS and did not address the progressive nature of the disease.

The researchers were unable to determine whether patients can fluctuate between MSa and MSb or if they remain in one category.

There was also a lack of data regarding the patients who were not on medication. The researchers could not determine if medication changed the course of the disease.

“Much future research is necessary to delineate the clinical correlations of these distinct variations of MS and determine if the distinction between the variations is clinically meaningful and useful,” said Dr. Chiaravalloti.

The study was published in September in Science Translational Medicine.

Affymetrix Inc generated microarray data for the study. Some study authors receive funding from a Fondazione Italiana Sclerosi Multipla research fellowship, National MS Society.

Some authors are consultants for TEVA, Biogen Idec, EMD Serono and Bayer Pharmaceuticals.

Reviewed by: 
Review Date: 
September 26, 2012
Last Updated:
September 26, 2012