Acadia Pharmaceuticals ($ACAD) heralded positive pivotal data for its late-stage Parkinson's contender pimavanserin this morning, marking a big turnaround for a program that had spurred more doubt than hope when a similar Phase III effort was scuttled by a big placebo effect back in 2009.
Impressed by the data, investors swiftly bid up Acadia's shares by 150%.
Three years ago Acadia was forced to acknowledge that pimavanserin--an oral 5-HT2A receptor inverse agonist--had been edged out by a placebo when it measured hallucinations and delusions domains using a score for Parkinson's disease symptoms. Its stock price was eviscerated and its partner on the drug--Biovail--soon after bowed out after merging with Valeant, a pharma company well known for its aversion to R&D. But this morning the developer noted that the drug hit its primary endpoint on significant antipsychotic efficacy using a 9-point measuring scale which had been adapted from the earlier, failed, approach. There were also measured improvements in sleep, wakefulness and caregiver burden.
Roger Mills, the EVP for development, says that narrowing the 20-point scale used in the failed Phase III down to the 9 relevant measurements--with the FDA's blessing--helped eliminate some of the "noise" seen in earlier data. The company also made sure to enroll more severely afflicted patients, avoiding the moderate cases more likely to demonstrate a placebo response and skew the data.
The focus now, CEO Uli Hacksell tells FierceBiotech today, will be on executing a confirmatory Phase III for Parkinson's psychosis, follow up on promising animal data for Alzheimer's psychosis and pursue the mid-stage program for pimavanserin in schizophrenia. There's no precise timeline on an NDA, he adds, but the next late-stage trial is also expected to run for about two years. And there are no immediate plans for a partnership.
"Our strategy is to move forward aggressively internally," says the CEO.
"These data represent an unprecedented advance for Parkinson's patients who suffer from the psychosis frequently associated with this disease," said Dr. Jeffrey Cummings, the director of the Cleveland Clinic Lou Ruvo Center for Brain Health, in a prepared statement. "Among Parkinson's patients, psychosis is the leading cause of institutionalization and dramatically increases the risk of mortality. Neurologists have limited options to treat this serious disorder, and off-label use of current antipsychotics is linked to increased risk of death and serious adverse events, as well as loss of motor control. The results of this study suggest that a selective, non-dopaminergic-based therapy has the potential to transform the treatment landscape for patients with this debilitating disorder."
The biotech reported that the pimavanserin arm demonstrated a 5.79-point improvement in psychosis at day 43 compared to a 2.73-point improvement for placebo, "representing a highly significant and clinically meaningful treatment difference of 3.06 points on SAPS-PD (p=0.001)." Investigators also reported there was no evidence of worsened motor function for patients in the drug arm, hitting a secondary endpoint in the study.
- here's the press release
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