[intro music] Host – Dan Keller Hello, and welcome to Episode Eighty-three of Multiple Sclerosis Discovery, the podcast of the MS Discovery Forum. I’m Dan Keller. For years, MS researchers have been looking for a measure of MS progression and disability that would be meaningful to clinicians, clinical researchers, patients, and the regulatory agencies that approve new drugs, such as the Food and Drug Administration. To this end, people have looked to composite endpoints that are sensitive to small changes in patient condition and comparable across studies. At the ECTRIMS conference last fall in Barcelona, I met with Dr. Jerry Wolinsky, professor of neurology and director of the MS Research Group at the University of Texas Health Science Center at Houston, who leads us along the path to develop a useful measure incorporating composite endpoints. Interviewer – Dan Keller In terms of assessing progression and disability in MS, is there some advantage to having composite endpoints as opposed to the standard tests we’ve looked at? Interviewee – Jerry Wolinsky There are several different ways to think about composite endpoints. So one of the things that was introduced almost several decades ago was MSFC functional composite. So this was using three different ways of looking at different components of disability in patients with MS. One was a test of cognition. One was a test of fine motor skills in the upper extremities. And one was a test of walking abilities/walking speed. That particular composite looked very attractive. There was a fair amount of theoretical and practical work behind instituting the composite, and it was used in a number of trials. And it was based on some very important, I think, kind of statistical analysis. So what it allowed one to do was to take patients either in a given study or across studies and try to normalize the data that you would get from those patients into something called a z-score, which is a way of ranking and evaluating how far across the group of patients people were scattered. And then one could conceptually add up the z-scores and have a composite number, and a single number that you could use to analyze trial data. It seemed to be rather sensitive, and it seemed to work well. But the z-score is very dimensionless, and it makes little sense to the practicing clinician, or certainly to patients, to know that you’re minus-two or minus-five or plus-two, and that maybe this has moved by two-hundredths of a point from the time you started in the study until you got to the end of the study. So, highly sensitive, seemed very reproducible, maybe even a way to look across studies at different results, but neither patients or physicians and, most importantly, the FDA thought that this would be useful in day-to-day practice. So, while we’ve tested that kind of approach in multiple studies, it just hasn’t worked. But it did set up the notion that we could get a little bit more quantitative in things that could be useful on a daily basis, even using some of the same components of that MSFC. So instead of thinking about how fast could one person walk compared to another, we said, how fast can a person walk using a timed walk of a fixed distance and at one point in time? And then say how much change over an interval of time would represent something that was likely to be reproducible and, more importantly, likely to be correlated with some measure of quality of life that also was deteriorating? So then we got to the notion–and this was really best utilized thus far in the trials of 4-aminopyridine in terms of registration studies there–to say could you show a 20% improvement or more in this timed walk over an interval of time? And in that study, a certain number of patients were able to show it, and there was also some correlative data done to show that that amount of improvement correlated with things which were meaningful