The benefits of an antipsychotic treatment for people with dementia-related psychosis have been demonstrated in a new study.
A clinical trial has tested the efficacy of the drug pimavanserin on people with Alzheimer’s disease, Lewy body dementia, frontotemporal dementia, and vascular dementia. Researchers discovered significant sustained benefits of the treatment, when compared to those put onto a placebo.
The findings have been published in the New England Journal of Medicine.
Globally, up to half of the 45 million people living with Alzheimer’s disease will experience psychotic episodes. This figure is even higher in other forms of dementia. Despite this, however, there is currently no approved safe and effective treatment for these symptoms. At present, widely-used antipsychotics for people with dementia can lead to sedation, falls, and increased risk of deaths.
Pimavanserin blocks serotonin 5HT2A receptors and does not interact with the dopamine receptors. It is licensed in the US to treat hallucinations and delusions in people with Parkinson’s disease psychosis.
In the study of 392 people with dementia-related psychosis, researchers administered pimavanserin to all participants for 12 weeks. Those who met a threshold of symptom improvement were then assigned to pimavanserin or a placebo for up to 26 weeks.
Reduced relapse rates
The trial was stopped early for positive efficacy results. Of the 351 participants, 217 (61.8%) had a sustained initial treatment benefit – with 112 of these then assigned to the placebo and 105 to pimavanserin. Relapse occurred in 28 out of 99 (28.3%) participants in the placebo group, compared to 12 out of 95 (12.6%) of the pimvanserin group. This shows that pimvanserin more than halved the relapse rate and significantly improved the sustained benefit.
Professor Clive Ballard, Executive Dean of the University of Exeter Medical School, said: “Psychosis affects up to half of all people with dementia, and it’s a particularly distressing symptom – yet there’s currently no safe and effective treatment. Currently used antipsychotics are known to cause harms, and best practice guidelines recommend prescribing for no longer than 12 weeks for people with dementia as a result. We urgently need alternatives. It’s exciting that the relapse rate in the pimavanserin group was lower than the placebo group, indicating that the treatment benefits may be sustained over time. We now need longer and larger scale trials to explore this further.”
The trial found headache, urinary tract infection and constipation occurred more frequently in the pimavanserin group, but there was no increase in mortality or other serious side effects, such as stroke, which are known to increase with other antipsychotics.