Saturday, August 16, 2014

Acadia Pharmaceuticals - Sleep Disturbance Study

During the second quarter conference call ACAD had mentioned that they are planning a "sleep disturbance" clinical trial for Parkinson's disease patients either in the 4th quarter of 2014 or first quarter 2015. This post will examine the potential market size for Parkinson's Disease patients who have sleep disturbances.
Sleep disturbances which include sleep fragmentation, day-time somnolence, sleep-disorder breathing, restless leg syndrome, nightmares and rapid eye-movement sleep behavior disorder, are estimated to occur in 64% of patients with PD according to this study, PD and Sleep Disorders...
So independent of patients with Parkinson's Disease Psychosis (PDP) and obviously there will be some overlap of the 30-40% who experience psychotic behavior, and up to 64% that experience "sleep disorders", out of the estimated one million in the U.S. with Parkinson's Disease could benefit from Pimavanserin. 
During the phase 3 trial that Acadia ran from 2010-2012 for Parkinson's Disease Psychosis patients, the company pulled some data that included sleep patterns among the treatment group that was given Pimavanserin.















Charted above is the sleep data using the SCOPA - sleep scale. Both nighttime sleep and daytime wakefulness was improved in the Pimavanserin treated group (blue line) compared to the control group (placebo) trial participants.  Data from another study the company completed Pimavanserin Sleep Study in 2006 with 45 healthy subjects to evaluate slow wave sleep (SWS) in a double blinded placebo study, found that the treatment group had positive results at the 5 mg and 20 mg level sustainable from day one and day 13 evaluation periods. These observations have led the company to pursue a sleep disturbance trial for this fragile group of patients.  Potentially if the trial proves to be effective similar to the previously run phase 3 trial, then the market for Pimavanserin could potentially grow approximately 24% to 34% to a total of 64% in the U.S. What is likely to occur if a trial is successful, is that the FDA could expand their label to include sleep disturbances in addition to PDP.   

Patients with Alzheimer's disease (AD) have similar sleep disturbances. According to this study Pharmacotherapies for sleep disturbances in Alzheimer's disease,  the authors found no significance in the drugs melatonin, or ramelteon for patients with Alzheimer's disease that experience sleep disturbances.  There was some evidence to support a low dose of trazodon (50mg), but larger trials were needed to reach a definitive conclusion.  An unmet market that Pimavanserin could potentially serve, in addition to Parkinson's patients with sleep disturbances.  There are approximately four times the number of AD patients compared to PD patients in the U.S.  The company is currently in a clinical phase 2 trial to test Pimavanserin for patients with Alzheimer's disease that have experienced psychosis (ADP).  Those results are not expected until mid to late 2015.  Within those results, and similar to the phase 3 study for PDP, should yield more data on sleep patterns for the treatment group in that trial. 

The company is doing a nice job of expanding their lead drug Pimavanserin beyond Parkinson's Disease Psychosis (PDP), but also within that population, sleep disturbance studies, and potentially Schizophrenia studies as a mono therapy or coupled with already available drugs. Thank you for reading.

No comments:

Post a Comment