Part 1:~Five (5) single-ascending oral doses will be administered to 40 healthy adult male or female subjects (aged 18-55 years, inclusive). Escalation to the next higher dose level may occur only after evaluation of the safety and PK results of the previous dose level (at least 6 evaluable subjects). Within each cohort, 6 subjects will receive one dose of ASN51, and 2 subjects will receive one dose of matching placebo. Based on this interim safety evaluation, dose levels may be revised.~Part 2:~Multiple ascending oral doses will be administered to 24 healthy elderly subjects (aged 55 - 80 years, inclusive) in 3 sequential dosing groups (8 subjects in each dosing group). Six (6) subjects will receive ASN51 and two (2) subjects will receive matching placebo in each dosing group (cohort) for 10 days. Escalation to the next higher dose level may occur only after evaluation of the safety and PK results of the previous dose level (at least 6 evaluable subjects). Based on this interim safety evaluation, dose levels may be revised.~Treatment of the subjects of each cohort will be administered as follows:~Day 1 - 9: Twice daily (BID) dosing (or once daily (QD) dosing); to be defined after Part 1 (SAD) of ASN51 or placebo.~Day 10: Only one dose will be administered in the morning of Day 10 Selection of the dosing regimen and dose levels to be administered in Part 2 will be made by the safety review committee (SRC), depending on the results of Part 1.~Part 3:~Multiple oral doses will be administered to 12 AD subjects (aged 55-85, inclusive) in a single dosing group for 10 days. Eight (8) AD subjects will receive ASN51 and four (4) AD subjects will receive placebo in that dosing group (cohort). Selection of the dose level to be administered in Part 3 will be made by the SRC and will depend on the results of study Part 1 (SAD) and Part 2 (MAD), and will be below the maximum tolerated dose administered to healthy subjects in Part 2.~Treatment of the AD subjects will be administered as follows:~Day 1 - 9: Twice daily (BID) dosing (or once daily (QD) dosing); to be defined after Part 2 (MAD) of ASN51 or placebo.~Day 10: Only one dose will be administered in the morning of Day 10. Selection of the dosing regimen and dose level to be administered in Part 3 will be made by the safety review committee (SRC), depending on the results of both Part 1 and Part 2.
ASN51-101 is a randomized, double-blind, placebo-controlled, phase 1 first in human (FIH) safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) study of oral ASN51 in healthy young adult and elderly subjects and elderly subjects with AD. The study is comprised of three parts (Part 1, Part 2, and Part 3).