Efficacy of DM/Q Tested in Treating Involuntary Laughter/Crying in Dementia Patients

VANCOUVER, BC—Dextromethorphan/quinidine (DM/Q) is effective in treating pseudobulbar affect (PBA: involuntary laughing and crying) associated with dementia, stroke and traumatic brain injury (TBI), according to findings presented at the 68^th AAN Annual Meeting.

“PRISM II is the first prospective, systematic study to evaluate DM/Q effectiveness (including safety and tolerability) for PBA secondary to dementia, stroke, or TBI,” wrote Joao Siffert, MD, chief medical officer at Avanir Pharmaceuticals in Aliso Viejo, CA, and coauthors, in a poster presentation.

“The observed PBA symptom reduction in this trial was consistent with that seen in well-controlled DM/Q phase 3 trials conducted with patients with ALS or MS,” the researchers reported.

The findings “demonstrate DM/Q effectiveness for PBA regardless of neurologic etiology,” they concluded. Improvements “appeared to be clinically meaningful.”

Inclusion criteria for the study included PBA diagnosis and a Center for Neurologic Study-Lability Score (CNS-LS) of ≥13, and a clinical diagnosis of stable or not-rapidly-changing dementia, stroke, or non-penetrating TBI. Depression, psychotic disorders, substance abuse and severe dementia were all exclusion criteria.

“All patients received DM/Q 20/10mg twice daily (once daily during Week 1),” the authors reported. A total of 298 patients were evaluable for DM/Q effectiveness and 271 completed the study through Day 90, at which point the mean CNS-LS score of the group reduced from baseline by -7.7 (standard deviation [SD] 6.1; P<0.001).

“Overall, PBA episodes were reduced by an estimated 57.5% at Day 30 and 72.3% at Day 90, compared with baseline” (P<0.001 for both), the researchers reported.