GCG and Parkinson disease: Importantly, two phase II trials in PD patients showed good effects with the GLP-1 receptor agonists Exendin-4 and Lixisenatide.<h4>Methods</h4>We have developed a dual GLP-1/GIP receptor agonist (DA5-CH) that can cross the blood-brain barrier (BBB) at a higher rate than Tirzepatide.