Alzheimers Dement. 2023 Dec;19 Suppl 24:e082642. doi: 10.1002/alz.082642.
ABSTRACT
BACKGROUND: Varoglutamstat (PQ912) is an oral, small molecule inhibitor of glutaminyl cyclase, preventing the formation of neurotoxic N3pE amyloid. A Phase 2a study (NCT02389413, Scheltens et al., 2018) reported encouraging first evidence of varoglutamstat’s disease-modifying activity, most importantly with statistically significant changes from baseline in working memory after only 12 weeks of treatment.
METHOD: VIVIAD (NCT04498650, Vijverberg et al., 2021) is an informed multicenter, randomized, placebo-controlled, double-blind, parallel group dose-finding Phase 2b study in 250 patients with Mild Cognitive Impairment (MCI) and early Alzheimer´s disease (AD). Treatment duration varies between 48 and 96 weeks depending on the time of inclusion, with participants receiving 300mg or 600mg varoglutamstat, or placebo, twice-daily (BID). The participants’ disease status at time of inclusion was confirmed by Abeta1-42 and phospho-tau CSF biomarker profiles, various cognition tests including MMSE, DSST/WAIS-IV Coding test (WAIS-IV), and A-IADL-Q. Primary outcome is a composite score of the cognitive domains attention and working memory using the Cogstate Neuropsychological Test Battery (Cogstate NTB).
RESULT: Enrollment has been completed, with a total of N = 259 patients randomized. The 300mg BID varoglutamstat arm was switched to 600mg BID based on positive independent Data Safety Monitoring Board review in June 2022. As of April 14, 2023, 23 patients had completed 96 weeks of treatment. The study will continue until the last patient has completed 48 weeks of treatment with the corresponding follow-up visit. While most AD trials focus on cognitive tests assessing memory deficits rather than working memory and attention, VIVIAD uses WAIS-IV to select patients with rescuable cognitive deficits in the target domains. In contrast to MMSE, WAIS-IV performance shows a reasonably good correlation with the primary outcome measures. Comparing baseline data of male and female participants showed no significant gender differences except for Abeta1-42 levels.
CONCLUSION: The use of MMSE and DSST/WAIS-IV together with CSF biomarkers is a valuable tool in identifying and recruiting patients with MCI or mild AD. The strategy of recruiting individuals with evidence of baseline deficits on the WAIS-IV Coding test has successfully enriched the study cohort with respect to deficits in attention and working memory, enabling reliable assessment of potential cognitive improvement after treatment.
PMID:39120888 | DOI:10.1002/alz.082642
