Clinical trials of a new drug intended to control hallucinations associated with advanced Parkinson’s disease also have become a trial in perseverance for San Diego’s Acadia Pharmaceuticals (Nasdaq: ACAD).
Despite a big setback three years ago, the company is reporting some encouraging results today in a comeback study evaluating the efficacy, tolerability, and safety of its pimavanserin drug in treating Parkinson’s disease psychosis. The company says pimavanserin met the primary and key secondary endpoints in a pivotal late stage trial, which the company repeated—at a cost of roughly $15 million—after a similar trial failed in 2009.
The outcome means Acadia is now laying plans for what should be a final, confirmatory, pivotal trial of pimavanserin that would likely take two years to complete. Perhaps after that, Acadia says it would be in a position to submit a new drug application for pimavanserin with the FDA. (Acadia has scheduled a conference call and webcast with investors and financial analysts today, beginning at 8 a.m. ET.)
“We are very excited with the results of this study, which really shows the potential of pimavanserin,” Acadia CEO Uli Hacksell said in phone interview late yesterday. The drug represents “a really major unmet medical need,” he said, because pimavanserin—unlike other antipsychotics—can be combined with the drugs used in patients with Parkinson’s to control tremors and other motor control symptoms.
Acadia’s drug reduced hallucinations in nearly all Parkinson’s patients in the study, without worsening their motor function, Hacksell said. Pimavanserin also is non-sedating, unlike many antipsychotics, which Hacksell said helped the patients sleep more soundly. And that helped to alleviate the burden among caregivers. “When you have a patient with Parkinson’s disease psychosis, there is a lot of stress on the caregiver, who is usually the spouse,” Hacksell said. It is the biggest reason why patients are institutionalized.
Nearly 1 million people in the United States are living with Parkinson’s, which is a chronic and progressive neurodegenerative disease, according to the American Parkinson Disease Association. About 4.6 million people around the world have Parkinson’s, and between 40 percent and 60 percent suffer from psychosis.
In September, 2009, the price of Acadia shares collapsed after the company reported results of a similar pivotal trial with almost 300 patients. That study, which also cost about $15 million, was unable to show a significant reduction in the number of hallucinations and delusions among Parkinson’s patients who were given pimavanserin in comparison with those who got a placebo.
Acadia overhauled the pivotal study to include five design enhancements. A couple of the biggest differences, Hacksell said, is that the latest study was done entirely in North America, and utilized an independent centralized rating service to measure antipsychotic efficacy in accordance with a 9-item scale of hallucinations and delusions adapted for Parkinson’s disease from the Scale for the Assessment of Positive Symptoms (SAPS-PD). The prior trial included patients in Eastern Europe and India and lacked the same type of centralized rating service, Haskell said.
The monumental do-over required Acadia to raise about $15 million in early 2011 to bolster its cash position, and the company said it had about $23 million in available cash at the end of September. Acadia CFO Tom Aasen said it won’t be enough to carry the company all the way through its last pivotal trial.
Acadia also parted ways with Canada’s Biovail, which had paid $30 million upfront in early 2009 as part of a pimavanserin-based strategic alliance, after Biovail merged with Valeant Pharmaceuticals in 2010. Acadia got a $9 million payment and regained full rights to pimavanserin, Aasen said.
It was unclear, though, whether Acadia is planning another financing or if the company might seek a strategic partner to advance the work on pimavanserin. Hacksell underscored that the company sees multiple additional opportunities for pimavanserin in addressing other neurological disorders, including Alzheimer’s disease psychosis and schizophrenia.
The company says it also has other drugs in its development pipeline, including collaboration with Allergan to develop two drugs—one for treating chronic pain and the other for glaucoma—along with two preclinical programs focused on Parkinson’s disease and other neurological disorders. Still, the San Diego drug company has a lot riding on the continued success of its lead drug candidate.