A 24-week open-label extension study of memantine in moderate to severe Alzheimer disease

Arch Neurol. 2006 Jan;63(1):49-54. doi: 10.1001/archneur.63.1.49.


Background: This study is an extension of a 28-week, randomized, double-blind, placebo-controlled study of memantine in 252 patients with moderate to severe Alzheimer disease.

Objective: To evaluate long-term memantine treatment in moderate to severe Alzheimer disease.

Design, setting, and patients: Open-label, 24-week extension trial. Raters remained blind to the patients' initial study treatment. Patients (n = 175) were enrolled from the previous double-blind study in an outpatient setting.

Intervention: Twenty mg of memantine was given daily.

Main outcome measures: Efficacy assessments from the double-blind study were continued and safety parameters were monitored.

Results: Patients who switched to memantine treatment from their previous placebo therapy experienced a significant benefit in all main efficacy assessments (functional, global, and cognitive) relative to their mean rate of decline with placebo treatment during the double-blind period (P<.05). The completion rate for the extension phase of the study was high (78%) and the favorable adverse event profile for memantine therapy was similar to that seen in the double-blind study.

Conclusion: These results extend previous findings that demonstrated the efficacy and safety of memantine in the treatment of patients with moderate to severe Alzheimer disease.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / drug therapy*
  • Alzheimer Disease / physiopathology
  • Disease Progression
  • Double-Blind Method
  • Excitatory Amino Acid Antagonists / therapeutic use*
  • Female
  • Humans
  • Male
  • Memantine / therapeutic use*
  • Mental Status Schedule / statistics & numerical data
  • Neuropsychological Tests / statistics & numerical data
  • Time Factors
  • Treatment Outcome


  • Excitatory Amino Acid Antagonists
  • Memantine