Claims of efficacy and safety based on open-label extensions of clinical trials create misinformation and unrealistic expectations about important treatments, can undermine otherwise compelling trials evidence, and have no place in academic journals. The evidence for the efficacy and safety of memantine rests on the well-conducted and methodologically sound randomized controlled trials as summarized by the Cochrane meta-analysis.1 Open label extension studies are essentially case series of the survivors of these trials who then choose to take the medications openly. These studies by design cannot contribute either safety or efficacy evidence no matter how we choose to analyze them.
Schneider LS. Open-Label Extension Studies and Misinformation. Arch Neurol. 2006;63(7):1036. doi:10.1001/archneur.63.7.1036-a