E-Mail MINNEAPOLIS - People with the advanced form of multiple sclerosis (MS) called secondary progressive MS who took the drug siponimod for one to two years had improved cognitive processing speed compared to those who did not take the drug, according to a new study published in the December 16, 2020, online issue of Neurology®, the medical journal of the American Academy of Neurology. Cognitive processing speed is the amount of time it takes someone to take in information, process it and then react to solve a problem or complete a task. It can affect many aspects of a person's daily life including employment, driving skills and social activities.