This is an open label, fixed sequence, 1-way crossover drug-drug interaction (DDI) study in healthy participants.

This is a phase 1, open-label, fixed sequence, 1-way crossover study examining the effect of itraconazole on the pharmacokinetics, safety and tolerability after varegacestat single dose administration to healthy participants. This is a 2-period study. In period 1 a single dose of varegacestat will be administered with PK evaluated predose and up to 192 hours postdose. There will be a 14 -day washout between period 1 and period 2. In period 2, itraconzole will be administered once daily for 18 consecutive days. Beginning on Day 4 of Period 2 a single dose of varegacestat will be administered 30 minutes after itraconazole dosing. Blood samples for PK will be collected prior to varegacestat dosing and up to 744 hours post varegacestat dosing for varegacestat and its metabolite.

Inclusion Criteria:

• Healthy, adult, male or female (of non-childbearing potential only), 18 to 55 years of age, inclusive, at the screening visit.
• Medically healthy with no clinically significant medical history, physical examination, clinical laboratory profiles, vital signs, and ECGs, as deemed by the PI or designee

Exclusion Criteria:

• Mentally or legally incapacitated or has significant emotional problems at the time of the screening visit or expected during the conduct of the study.
• History or presence of clinically significant medical or psychiatric condition or disease in the opinion of the PI or designee.
• History of any illness that, in the opinion of the PI or designee might confound the results of the study or poses an additional risk to the participant by their participation in the study.