Primary objectives:~To evaluate the safety and tolerability of single and multiple doses of Delcetravir in healthy subjects (18-50 years of age).~To evaluate the safety and tolerability of single and multiple doses of Delcetravir in healthy subjects (50-80 years of age).~To evaluate the pharmacokinetics (PK) of Delcetravir after single and multiple doses of ESFAM289 in healthy subjects (18-50 years of age).~To evaluate the PK of Delcetravir after single and multiple doses of Delcetravir in healthy subjects (50-80 years of age)~Secondary objectives:~To compare the PK of Delcetravir after single and multiple doses of Delcetravir in age stratified subjects (18-50 vs. 50-80 years of age).~To compare the safety and tolerability after single and multiple doses of Delcetravir in age stratified subjects (18-50 vs. 50-80 years of age).
This study will be a single center, Phase I, randomized, double-blind, placebo controlled, single and multiple ascending dose (SAD/MAD) study evaluating the safety, tolerability, and PK of Delcetravir after administration via oral inhalation in healthy subjects.