This is a randomized, double-blind, first-in-human, placebo-controlled single ascending dose study to study the safety, tolerability, PK, and PD of EXT608 in healthy adult participants.~Participants will be enrolled into 1 of up to 6 planned single dose cohorts in ascending fashion.~Each cohort will consist of 4 participants randomized to receive either EXT608 or placebo, whereby 3 will receive a single injection of EXT608 and 1 will receive matching placebo.~Up to 6 dosing cohorts are planned with no single dose escalation to exceed a 3-fold dose increment. A Data Monitoring Board will review the seven-day safety data in each cohort before authorizing the initiation of the next cohort.~A screening visit will take place within 28 days of dosing. Eligible participants for each cohort will be admitted to the Clinical Research Unit (CRU) 1 day prior to dosing and remain in the CRU through at least 72 hours after dosing for safety and PK assessments before discharge. The total confinement period will be 4 nights, unless extended for management of AEs at the discretion of the Investigator
This is a Phase 1, randomized, double-blind, placebo-controlled, single ascending dose safety and tolerability study of EXT608 in healthy subjects. There will be up to 6 sequential dose escalation cohorts of 4 participants. In each cohort 3 participants will receive EXT608 and 1 participant will receive placebo.