Pimavanserin tartrate is a serotonin (5-HT2A) receptor inverse agonist used to treat patients with Parkinson's disease who experience psychiatric disorders such as hallucinations or delusions.

About Parkinson: There are about 10 million Parkinson's patients in the world, and according to statistics, China has nearly 2.5 million to 3 million Parkinson's disease patients, making it the country with the most Parkinson's disease patients in the world. There are about 100,000 new patients every year, and the incidence rate of people over 65 years old is 1.7%, while the medical treatment rate accounts for only 40%, and less than 500,000 people can be truly diagnosed and treated due to missed diagnosis and misdiagnosis. About 70% of patients with Parkinson's disease will progress to Parkinson's dementia, and more than 50% of patients with Parkinson's disease and 75% of patients with Parkinson's dementia sometimes have psychiatric symptoms.

About Parkinson's disease psychosis (PDP): often present in Parkinson's disease, manifestations include hallucinations, delusions, delusions, confused thinking, delirium, etc., which are common triggers for mobility disorders and hospitalization in Parkinson's patients, which not only complicate disease management, but also induce illness, dementia and death. Parkinson's disease psychosis is a major challenge in treatment because dopamine drugs are ideal for managing motor symptoms, but they can worsen them. Parkinson's disease can also be worsened when antipsychotic drugs are used to treat psychiatric symptoms.

Regarding the treatment of PDP: first-line drug: pimavanserin, not only can significantly improve the hallucinations and delusions of patients with Parkinson's disease psychosis, and the treatment of Parkinson's disease psychosis is safe and effective, but also, because it has no effect on dopamine, high doses will not induce stiffness, will not cause other movement disorders, and can preserve motor function.