The University of Rochester Medical Center (URMC) is leading a multi-center clinical research study of a new experimental treatment for Tourette's syndrome. The study will examine whether or not a drug that alters the chemical activity in the brain can alleviate the symptoms of the disease.
Tourette's syndrome (TS) is a neurological disorder characterized by multiple, repeated tics. These tics generally consist of abrupt and involuntary vocal outbursts or muscular jerks. Symptoms usually begin at an early age and can increase in frequency and severity over time. Many individuals with TS have a mild form of the disease and do not require medical intervention unless the tics interfere with normal daily function.Patients with more severe forms of TS are currently treated with various antipsychotic drugs
"While the precise mechanism that causes Tourette's is unknown, we have long observed that the neuro-chemical dopamine is overly active in individuals with the disease," said URMC neurologist Roger Kurlan, M.D., the study's principal investigator. "This chemical imbalance in the brain may play a role in the disease and, consequently, the drugs that are currently used to treat the disease are known to suppress dopamine production.However, these drugs are also associated with severe side effects that often deter their use."
Kurlan and his colleagues are studying a drug called Mirapex (pramipexole). The drug is approved by the Food and Drug Administration for use in patients with Parkinson's disease and restless leg syndrome.Mirapex is a dopamine agonist; it stimulates dopamine production in the brain. Small pilot studies with the drug in TS patients have shown good outcomes and few side effects. Mirapex is investigational in patients with Tourette's syndrome.
"It would seem to be counter-intuitive to stimulate more chemical activity in the brain when we know that there already is an imbalance in Tourette's patients," said Kurlan. "However, we believe that this might actually cause the dopamine receptors in the brain to adapt and desensitize so that they start reacting less to the overactive dopamine."
Kurlan is the head of the Tourette's Syndrome Study Group, an international network of researchers who are involved in almost every major clinical study of the disease. It was work by Kurlan and his colleagues in 2001 in schools in Monroe County, New York that demonstrated that TS is far more prevalent than previously realized.His research found that 1 in 4 children in special education programs in the region's schools exhibited some form of tics or TS. Kurlan and his colleagues were also instrumental in establishing the hereditary nature of disease which helped dispel the previously held notion that TS was a psychological disorder.
Kurlan and his colleague Jonathan Mink, M.D., Ph.D. also run one of the larger TS clinics in the country; at any one time, URMC physicians are following more than 2,000 TS patients from across upstate New York and northern Pennsylvania.
URMC is seeking the families of children or adolescents who are bothered by their tics to participate in the study.The study is being funded by Mirapex's manufacturer, Boehringer Ingelheim Pharmaceuticals, and there is no cost to participants.The study lasts for 6 weeks, with the option for patients to continue the medication for a longer period.