On April 29, 2016, the FDA approved pimavanserin (Nuplazid; Acadia), an atypical antipsychotic, for the treatment of hallucinations and delusions associated with Parkinson’s disease. Pimavanserin is the first drug approved by the FDA for hallucinations and delusions that are associated with Parkinson’s disease.
“Hallucinations and delusions can be profoundly disturbing and disabling. Nuplazid represents an important treatment for people with Parkinson’s disease who experience these symptoms,” said Mitchell Mathis, MD, Director of the FDA’s Division of Psychiatry Products.
As many as 50% of patients with Parkinson’s disease experience hallucinations and delusions; these serious symptoms can add to the burden of physical limitations in patients with this disease.
Pimavanserin was approved under the FDA’s priority review status and was earlier granted a breakthrough therapy designation in an effort to expedite the development and approval process. Although its mechanism of action is still not fully understood, the effect of pimavanserin may be mediated through a combination of inverse agonist and antagonist activity at serotonin 2A receptor (5-HT2A) and, to a lesser extent, at serotonin 5-HT2C receptors.
The efficacy of pimavanserin was established in a randomized, placebo-controlled, parallel-group, 6-week clinical trial involving 199 patients with Parkinson’s disease who experienced hallucinations and/or delusions. Patients receiving pimavanserin had less frequent and/or less severe hallucinations and delusions, without worsening the primary motor symptoms of Parkinson’s disease, compared with those receiving placebo.
The most common adverse effects associated with pimavanserin were peripheral edema and a confused state. Pimavanserin was approved with a boxed warning cautioning healthcare professionals about the risk for death in elderly patients with dementia-related psychosis who use antipsychotic drugs.
Pimavanserin is not approved for the treatment of patients with dementia-related psychosis that is unrelated to hallucinations and delusions associated with Parkinson’s disease psychosis.