Acadia claims Alzheimer's success
- Results from a Phase 2 study of Acadia Pharmaceuticals' Nuplazid (pimavanserin), an experimental treatment for Alzheimer's disease psychosis, showed a statistically significant improvement in the primary endpoint compared with placebo, according to Tuesday announcement.
- After six weeks in the -019 Study, patients receiving Nuplazid showed a 3.76-point improvement compared with a 1.93-point improvement for placebo (p=0.0451). However, the reduction in psychosis was not significant after 12 weeks. There were no impairments in cognition over an additional 6 weeks of treatment. The most common adverse effects were falls, urinary tract infection and agitation.
- There are currently no drugs on the market for Alzheimer's disease psychosis, and Acadia's share price jumped by 12% on the trial results.
Despite producing statistically significant results in AD psychosis patients at six weeks, the data wasn't durable and the effect diminished by 12 weeks.
The lack of durability raised questions amongst investors and analysts. While the stock ticked up almost 50% in pre-market trading, excitement was tempered by the muted success of the drug and Acadaia shares only gained 12% by close of trading on Tuesday.
Yet, according to Reuters, Needham analysts suggested that the endpoint miss at 12 weeks was not expected to be a regulatory concern, as many antipsychotics are tested at six weeks, and added "we do not believe it is unreasonable to consider Nuplazid (pimavanserin) potentially useful in all dementia patients with psychosis."
Acadia Pharmaceuticals' pipeline is focused around Nuplazid. Following a 12-2 vote from the FDA's advisory committee that the benefit outweighed the risk in psychosis in Parkinson's disease, Nuplazid was approved in April 2016. This was the first drug approved for this indication in the U.S.
The drug is also in Phase 3 in schizophrenia as an adjunctive therapy in patients who have an inadequate response to other treatments. It is also in several Phase 2 trials – Alzheimer's disease agitation, negative symptoms of schizophrenia, and adjunctive therapy in major depressive disorder.
Around 5.4 million people in the U.S. have Alzheimer's disease, with a quarter to a half developing hallucinations and delusions. It's a large potential market, but companies studying drugs for Alzheimer's disease face a lot of questions at the moment, following a series of collapses and calamities in the development process.
- Acadia Pharmaceuticals Statement
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