Researchers use qMRI to confirm effect of CS treatment in patients with OA

Mar 5 2011

A group of Canadian researchers led by Prof. Jean-Pierre Pelletier, Head of the Osteoarthritis Research Unit at the University of Montreal Hospital Research Centre, published a clinical trial in which they confirm, for the first time using quantitative Magnetic Resonance Imaging (qMRI), the disease modifying effects of chondroitin sulphate, a symptomatic slow acting drug for osteoarthritis (SYSADOA).

This clinical trial, published in Annals of the Rheumatic Diseases (impact factor 8.111), explored the effect of chondroitin sulphate (CS) treatment on cartilage volume loss, subchondral bone marrow lesions (BML) and synovitis in patients with knee osteoarthritis (OA). "This study focused on quantifying over time by MRI the main structural changes observed in the cartilage, bone and synovial membrane", Prof. Pelletier said.

The investigator states that after only six months of treatment with CS, patients show a significant decrease in loss of articular cartilage as compared to the placebo group, and for the first time, a significant reduction in the progression of BMLs by 12 months.

According to Prof. Pelletier, these data highlight not only the importance of the interrelationship between cartilage and subchondral bone in OA, but also its potential role in the disease process and response to treatment with SYSADOAs.

Prof. Pelletier concluded that, "CS is a safe drug with an overall positive effect on OA, significantly reducing the volume of cartilage loss in knee OA, and providing for the first time new information on its positive effect in vivo on other structural changes observed in this disease".

Professor Pelletier commented that the clinical trial results prove that CS is able to slow the progression of OA, however this does not mean it is able to cure. "The cure involves the regression of all lesions related to OA," he says, "and that's not the case. Chondroitin sulphate slows the progression of the disease. This is an important finding as a decrease in the rate of progression of cartilage loss in knee OA patients, as seen by MRI, could potentially reduce the need for total knee replacement – a phenomenon that has been observed in other MRI clinical studies".

Confirming previous studies

The clinical trial by Prof. Pelletier definitively supports the findings of previous studies describing the positive effects of CS on the pathogenic mechanisms of action of OA (Kwan S et al 2007; Monfort J et al 2005; Bassleer et al 1998; Ronca de 1998, etc), and supports the ability of CS to modify the natural history of the disease, as previously demonstrated by Kahan (2009), Michel (2005), and Uebelhart (1998 and 2004), and the two meta-analyses by Hochberg (2008 and 2010).

Similarly, Prof. Pelletier said that these findings refute the conclusions reached by S. Wandel et al. in a meta-analysis published in the British Medical Journal (BMJ) in 2010 to the effect that SYSADOAs do not offer benefits in the treatment of patients with OA.

In this regard, Prof. Pelletier says, "the methodology used by Wandel et al. is questionable based on the opinion of several experts in the field of OA, as reflected by the several letters to the editor posted on the BMJ website, some of which have also been published in the official Journal. The results of the Wandel et al. meta-analysis are in contrast to many other meta-analyses performed by expert scientists dealing with the same issue, which have shown that CS is an effective symptomatic treatment for OA and that it can slow disease progression".

"In line with my previous comments, following the publication of this meta-analysis, one of the editors from BMJ issued an official statement in the BMJ website questioning some of the assumptions made in the article and also mentioning a possible conflict of interest of the BMJ senior statistics editor, thus seriously questioning the validity and reliability of this meta-analysis", Prof. Pelletier specified.

Future goals

The expert says the results of this pilot MRI study are very positive and encouraging. Given the evidenced efficacy and safety of the product, it definitely represents a most valuable option for OA patients. Though he notes, "it is important that patients are provided with highly purified pharmaceutical grade CS, the one used in this study, as this is the only one that can guarantee such efficacy and specifically, safety results".