Data are expressed as means ± SD. Statistical analysis was assessed by ANOVA. Significance in cell culture experiments was analyzed with the Tukey's post hoc test. The standard Mantel–Cox log‐rank test was used to assess survival. Significance of changes in neurological symptoms and tissue samples was analyzed with the Fisher's LSD post hoc test. All analyses were conducted with GraphPad Prism software. In animal studies, we used n = 7–14 mice/group for behavioral tests and n = 5 mice/group for biochemical analysis from the same litter; the five mice included in the analysis were selected at random. For the cell culture studies, we performed at least three independent experiments, in duplicates. An observer who was blind to the experimental groups conducted all the animal studies. From the age‐matched mice, one of eight TAT‐treated and two of sixteen P110‐treated mice were excluded from the study due to death during the surgery to implant the second pump. The data from these three mice were not included in any of the behavioral analysis.