Fire in the ashes: Can failed Alzheimer's disease drugs succeed with second chances?

We find support for our earlier proposal that (−)-phenserine did not fail, but the methods of development did fail, to provide conditions where efficacy could be tested. We propose that redevelopment under conditions aimed to correct methodological deficiencies common in AD drug developments will successfully test efficacy for (−)-phenserine and hopefully lead to a disease-modifying addition to the AD therapeutic armamentarium.