Pregabalin for the treatment of Cerebellar Ataxia with Neuropathy and Vestibular Areflexia Syndrome (CANVAS) associated chronic cough.

This study is divided into a two week Screening Phase, followed by 12 weeks of either placebo or pregabalin (treatment phase one) followed by a four week washout period where no drug/placebo is administered, followed by another 12 week period of either pregabalin or placebo (treatment phase two). At the end of 12 weeks there is a final safety period of four weeks (End Phase) were no drug/placebo is administered but the study team continues to follow the participants. Participants will receive pregabalin, as an oral capsule at 75 mg twice per day for 12 weeks within a 36 week cross over study. Unused tablets will be returned to dispenser for counting to monitor compliance. For participants who must reduce their dosage following intolerable adverse drug reaction, they will reduce to one capsule per day. For those who still experience unmanaged cough, they may increase their dosage. This will be increased to three capsules per day if they are tolerating the medication and their blood test results are not deranged. Participants may be offered this increase or decrease of dosage at the end of the first week of each treatment phase. Safety bloods are to be performed at screening, four weeks into treatment phase one and four weeks in treatment phase two. Additional safety bloods may be ordered in the medical opinion of the PI.