Positive Phase IV Data Reported for Nuedexta (Dextromethorphan/ Quinidine) in Patients With Alzheimer’s Disease/Dementia
Treatment reduces symptoms of pseudobulbar affect
Interim data from a new phase IV study has shown that treatment with Nuedexta (Avanir Pharmaceuticals) substantially reduced the symptoms of pseudobulbar affect (PBA) in patients with Alzheimer’s disease (AD)/dementia. PBA is a neurologic condition characterized by sudden and uncontrolled outbursts of laughing and/or crying in patients with neurologic disease or injury.
A standard quality-of-life (QOL) measure also showed clear improvement during the 3-month treatment period.
The findings were presented July 16 at the Alzheimer’s Association International Conference, held in Copenhagen, Denmark.
Nuedexta is a combination of dextromethorphan hydrobromide (20 mg), the ingredient active in the central nervous system, and quinidine sulfate (10 mg), a metabolic inhibitor enabling therapeutic dextromethorphan concentrations. Nuedexta acts on sigma-1 and N-methyl-D-aspartate (NMDA) receptors in the brain, although the mechanism by which it exerts its therapeutic effects in patients with PBA is unknown.
The PRISM II trial was an open-label, 12-week study involving approximately 450 patients with AD/dementia. Eligible subjects were 18 years of age or older with a clinical diagnosis of PBA and a baseline score of 13 or greater on the Center for Neurologic Study–Lability Scale (CNS-LS).
The study assessed the efficacy and safety of Nuedexta in treating PBA in patients with AD/dementia, stroke, or traumatic brain injury. At the time of the interim analysis, 68 patients with AD/dementia had evaluable efficacy data and 96 patients had evaluable safety after at least 30 days of treatment. The study endpoints included a PBA symptom rating (CNS-LS score of 7 [no symptoms] to 35 [maximum symptoms]); the number of weekly PBA episodes; the Mini-Mental State Examination (MMSE) score; QOL improvements (0 = no impairment; 10 = maximum impairment); and Clinician and Patient Global Impression of Change (CGI-C/PGI-C).
At baseline, the patients had a mean CNS-LS score of 20.2 and a median of 29 PBA episodes per week. At the end of the study, the mean CNS-LS improved to 12.8 (P < 0.001 compared with baseline), and the median number of PBA episodes decreased to five per week.
Mean QOL scores improved from 6.1 at baseline to 2.8 at endpoint (P < 0.001); 77.8% of patients or caregivers rated themselves or the patient as being much/very much improved on the PGI-C; and 79.3% of clinicians rated the patient to be much/very much improved on the CGI-C. In addition, the MMSE mean score improved by 0.4 points at end of the study from a baseline of 19.0.
Adverse events (AE) were reported by 35 (36.5%) patients (6.3% treatment-related). The most common AEs were headache (9.4%), urinary tract infection (5.2%), and diarrhea (4.2%). Eleven patients had serious AEs (only one deemed treatment-related). Thirteen patients discontinued treatment because of AEs.
Source: Avanir Pharmaceuticals; July 16, 2014.