CLINICAL DEFINITION FOR MULTIPLE-SCLEROSIS TREATMENT TRIALS

Clinically, the Schumacher Panel criteria remain the best set of diagnostic criteria. Two subsets therein are definable, i.e., exacerbating-remitting (ER) and chronic progressive (CP), with the latter subdivided into progressive from onset and secondarily progressive. A clinically stable stage can also be recognized. It has been customary in treatment trials to separate ER and CP patients. End point for the latter is a comparison of neurologic status at the end of the trial with that entry. A similar assessment can be made for ER patients. With this criterion both types could be included in a single study. One could also, though, treat the exacerbation in an acute study pr assess whether exacerbations can be prevented in a long-term trial. Most clinicians no longer consider monophasic disease as multiple sclerosis (MS). Depending on clinical extent, such patients are divisible into acute disseminated encephalomyelitis, Devic disease, transverse myelopathy, or optic neuritis. Each subgroup could be studied as with an acute exacerbation or in long term as to whether future and different neurologic insults can be prevented. One measure of neurologic status is the Disability Status Scale (DSS), which grades clinical impairment due to MS on a 0 (normal) to 10 (death due to MS) basis. The expanded DSS (EDSS) subdivides each step 1 through 9 into two. Type and severity of neurologic impairment is defined by graded involvement in the following eight functional systems (FS): pyramidal, cerebellar, brainstem, sensory, bowel and bladder, visual, cerebral, and other. frequency and severity of each FS correlates strongly with DSS scores. In treatment trials, change of one full step on (E)DSS can be used to define improvement or worsening for each patient.