An Exploratory Phase IIa Study of the PPAR delta/gamma Agonist T3D-959 Assessing Metabolic and Cognitive Function in Subjects with Mild to Moderate Alzheimer's Disease.

Background: T3D-959 is a chemically unique, brain penetrant, dual PPAR delta/gamma agonist with 15-fold higher PPAR delta selectivity. Ubiquitous brain expression of PPAR delta, its critical role in regulating glucose and lipid metabolism, and the Alzheimer's disease (AD)-like phenotype of PPAR delta null mice motivated this study. Objective: To determine safety and tolerability of multiple doses of T3D-959 in subjects with mild to moderate AD, examine systemic and central drug pharmacology and in an exploratory manner, perform cognitive assessments. Methods: Thirty-four subjects with mild-to-moderate AD were orally administered 3, 10, 30, or 90 mg of T3D-959 daily for 14 days. There was no inclusion of a placebo arm. Safety and tolerability were monitored. Systemic drug pharmacology was examined via plasma metabolomics LC-MS-MS analysis, cerebral drug pharmacology via FDG-PET measures of changes in Relative CMRg1 (R CMRg1, AD-effected regions relative to brain reference regions), and cognitive function assessed before and after drug treatment and again one week after completion of drug treatment, by ADAS-cog 11 and the Digit Symbol Substitution Test (DSST). Results: T3D-959 was in general safe and well tolerated. Single point pharmacokinetics at the T showed dose dependent exposure. Plasma metabolome profile changes showed dose-dependent systemic effects on lipid metabolism and metabolism related to insulin sensitization. Relative FDG-PET imaging demonstrated dose-dependent, regional, effects of T3D-959 on R CMRg1 based on the use of multiple reference regions. ADAS-cogl 1 and DSST cognitive assessments showed improvements with possible ApoE genotype association and pharmacodynamics related to the mechanism of drug action. Conclusions: Exploratory data from this Phase Ha clinical trial supports further clinical investigation of T3D-959 in a larger placebo-controlled clinical study.