The diabetes drug is Byetta and its generic name is exenatide. This drug was developed for Type 2 Diabetes but may be able to improve cognitive and motor function in Parkinson’s disease. A small study of 44 patients conducted by Dr. Thomas Foltynie from the National Hospital for Neurology and Neurosurgery in London has shown promise.
Of the 44 Parkinson’s subjects, 20 received twice daily injections of exenatide. Byetta (exenatide) is designed as a pen type device for self injection. Given the expense of manufacturing placebos into such a device, the control group received nothing. Subjects were followed for a year and evaluated periodically by a blinded investigator. Multiple rating scales were employed and subjects were rated both on and off medication at regular intervals throughout the study. At the conclusion of the study, investigators found that the subjects who received exenatide showed an almost 3 point improvement in both motor and cognitive function while the control group had a 2 point decline. Weight loss was the only side effect. .
But while the benefit and improvement seen in the control group is sufficient reason to initiate more statistically relevant clinical trials, there is another perhaps even larger benefit. This clinical trial utilized a medication that is already FDA approved and its basic safety and tolerability were already known. Given the enormous expense, the long period of development and animal studies and the risks involved in developing and studying new treatments or drugs for neuroprotection, this study was much more cost efficient as well as being a very rapid way of collecting information about the effectiveness and tolerability of this drug in a new population. Clearly, the results of this one small study are not sufficient to determine the efficacy of exenatide for Parkinson’s however, it does speed up the process of making more options available for symptomatic relief of Parkinson’s.