◆ GB-5001 was well tolerated in healthy male volunteers, with injection-site reactions being the most common adverse events and generally mild in severity.

◆ Following the single intramuscular administration, GB-5001 demonstrated approximately dose-proportional donepezil exposure over the 70-280 mg dose range.

◆ The prolonged absorption profile, characterized by delayed Tmax and extended apparent half-life, supports the feasibility of once-monthly intramuscular dosing.

◆ At steady-state, monthly GB-5001 maintained sustained plasma donepezil exposure with lower peak-to-trough fluctuation than daily oral donepezil.

◆ An integrated population pharmacokinetic model, informed by both the phase 1 study and the Indonesian pilot study, supported predictable accumulation and steady-state exposure comparable to oral donepezil.

 

GB-5001 was well tolerated in healthy male volunteers; injection-site reactions were the most common AEs and were generally mild.

SAD demonstrated linear, approximately dose-proportional PK over 70–280 mg IM, with a flip-flop profile (median Tmax 619.19–1176.00 h; mean t½ 286.91–314.3 h).

MAD steady-state data confirm sustained plasma exposure (Cav,ss ≈ 20 ng/mL at 140 mg q4w) with markedly lower fluctuation than daily oral donepezil.

The integrated PopPK model (two-compartment, parallel IM depots) supports GB-5001 as a once-monthly IM alternative providing predictable accumulation and steady-state exposure.