Dexpramipexole dihydrochloride ((R)-Pramipexole dihydrochloride) is a neuroprotective agent and weak non-ergoline dopamine agonist. In Vitro: Dexpramipexole has been found to have neuroprotective effects and is being investigated for treatment of amyotrophic lateral sclerosis (ALS). Dexpramipexole reduces mitochondrial reactive oxygen species (ROS) production, inhibits the activation of apoptotic pathways, and increase cell survival in response to a variety of neurotoxins and β-amyloid neurotoxicity. Compared to the S-(-) isomer, Dexpramipexole has much lower dopamine agonist activity.