Login to Your Account

'Acadia' Think It Really Works? After Two Fails, Phase III Win

By Randy Osborne
Staff Writer

Two strikes – and investor suspense – led up to a home run for Acadia Pharmaceuticals Inc., which tweaked the designs of previous, failed Phase III trials and thereby met all endpoints in the latest one with pimavanserin in Parkinson's disease psychosis (PDP).

"We did that in a smart way, so that we minimized placebo response and succeeded in suppressing variability," said Acadia CEO Uli Hacksell. "I think we have found a formula for success."

The nondopaminergic blocker of serotonin 5-HT2A receptors still must prove itself in another Phase III study to apply for FDA clearance, but the most recent success goes far to relieve doubts.

Wall Street rejoiced. San Diego-based Acadia's shares (NASDAQ:ACAD) closed Tuesday at $5.43, up $3.13, or 136 percent, after trading as high as $6.53.

Pimavanserin, taken as an oral tablet, met the primary endpoint in the trial known as Study 020, showing highly significant antipsychotic efficacy as measured using the 9-item SAPS-PD scale (p = 0.001).

Well tolerated as in previous trials, the compound also met the secondary goal: motoric tolerability, as measured using Parts II and III of the Unified Parkinson's Disease Rating Scale.

Acadia recorded a highly significant improvement in the secondary efficacy measure, too – the Clinical Global Impression Improvement, or CGI-I, scale (p = 0.001).

In fact, Hacksell said, pimavanserin performed well on every endpoint examined. "It's something you almost never see in a clinical trial," he said.

Study 020 improved over the previous two, known as 012 and 014, by using the highest dose (40 mg) proved safe and effective in earlier work, and by enrolling about 200 patients from only the U.S. and Canada, carefully screened using a test that ensured they were symptomatic. (See BioWorld Today, Sept. 2, 2009.)

The next Phase III trial, Study 021 , will be identical to 020, Hacksell told BioWorld Today. Like 020, it will probably take about two years, although "we may be able to shave off some time," he said.

Pimavanserin has reached the Phase II stage for schizophrenia and Alzheimer's disease psychosis (ADP). Needham & Co. analyst Alan Carr wrote in a research report that the bigger money lies in other indications. While PDP, with a market of about $500 million, "represents an attractive commercial opportunity for a company with a small sales force," positive data from Phase II work in schizophrenia could open the door to a $1 billion-plus in sales, Carr wrote.

Hacksell called the PDP market "sizeable," noting that 60 percent of Parkinson's disease patients develop psychosis, which is the main reason they end up in nursing homes. About 1 million are afflicted with Parkinson's in the U.S., and between 4 million and 6 million worldwide. About 40 percent of existing patients have PDP, and existing antipsychotic agents cannot be used in them.

The other diseases are "exciting opportunities," Hacksell acknowledged. ADP symptoms are similar to PDP, and Acadia will explore that space further "when we have the 021 study up and running full speed," he said. In schizophrenia, positive Phase II data showing a statistically significant antipsychotic effect in combination with Risperdal (risperidone, Johnson & Johnson) doubled Acadia's stock price when disclosed in 2007. (See BioWorld Today, March 20, 2007.)

Acadia has full rights to the drug. In the fall of 2010, the company and Biovail Laboratories International SRL (BLS), a wholly owned subsidiary of Aliso Viejo, Calif.-based Valeant Pharmaceuticals International Inc., ended their deal for pimavanserin in the U.S. and Canada. Acadia regained full ownership, and got a one-time cash payment of $8.75 million from BLS.

Acadia had about $23 million on hand at the end of the last quarter, said Thomas Aasen, chief financial officer. "We've been burning about $5 million per quarter on average, so it gives you a sense of the runway," he said, adding that the firm will evaluate the need for more cash, and how to get it, as the situation arises with pimavanserin, which he said has "the ideal profile" in PDP.