DENVER —
More than half of participants in the open-label extension period of the randomized clinical trial responded to the medication, which was associated with a 3.6-fold lower risk for relapse compared with placebo.
“The positive efficacy and favorable safety results with AXS-05 support its potential to fulfill a high unmet need for the treatment of Alzheimer’s disease agitation,” said Anton P. Porsteinsson, MD, director of the Alzheimer’s Disease Care, Research and Education Program, University of Rochester, New York.
The findings were presented at the 2024 annual meeting of the American Academy of Neurology.
Common and Disruptive
Agitation is reported in up to 70% of patients with Alzheimer’s disease and is characterized by emotional distress, aggressive behaviors, disruptive irritability, and disinhibition. Alzheimer’s disease-related agitation has been associated with increased caregiver burden, decreased functioning, accelerated cognitive decline, earlier nursing home placement, and increased mortality.
A previous phase 2/3 study of AXS-05 showed that the investigative agent led to rapid and significantly improvement in Alzheimer’s disease agitation, as measured by the Cohen-Mansfield Agitation Inventory (CMAI) total score, compared with placebo.
ACCORD was a phase 3, randomized, double-blind, placebo-controlled withdrawal trial evaluating the efficacy and safety of AXS-05 in patients with Alzheimer’s disease agitation.
In the open-label period, 178 adults with probable Alzheimer’s disease and clinically significant agitation received AXS-05 (titrated to 45 mg dextromethorphan/105 mg bupropion twice daily) for up to 9 weeks.
A total of 108 (61%) patients had a sustained response, with 30% or more improvement from baseline in the CMAI total score and improvement on the Patient Global Impression of Change that were both maintained for 4 or more consecutive weeks. These patients entered the double-blind phase and were randomly allocated to receive twice-daily AXS-05 or placebo for up to 26 weeks.
In the double-blind period, AXS-05 “substantially and statistically” increased the time to relapse of agitation symptoms compared with placebo (hazard ratio [HR], 0.275; P = .014).
“The risk of relapse was 3.6-fold lower with AXS-05 compared with placebo,” Dr. Porsteinsson reported.
AXS-05 was also associated with a significantly lower relapse rate compared with placebo (7.5% vs 25.9%; P = .018).
Rates of discontinuation in the double-blind period owing to adverse events (AEs) were low (0% for AXS-05 and 1.9% for placebo). Three serious AEs were reported: one in the AXS-05 group (fecaloma), which was not related to study medication, and two in the placebo group (cardiac arrest, femur fracture).
Falls were reported in four participants in the AXS-05 group, none of which were related to study medication or associated with serious AEs, and in two participants in the placebo group, one of which was associated with femur fracture.
One death was reported in the placebo group. There was no evidence of cognitive decline with AXS-05, and treatment was not associated with sedation.
Promising Agent
Commenting on this research, Glen R. Finney, MD, director of the Geisinger Memory and Cognition Clinic in Wilkes-Barre, Pennsylvania, said the data “look promising as a safe way to help address acute agitation and reduce agitation reoccurrence.