Enhanced bioavailability and short-term safety of a micellar green tea extract formulation co-delivered with N-acetylcysteine: a randomized crossover study in healthy adults.

INTRODUCTION

Green tea catechins, particularly epigallocatechin gallate (EGCG), the principal polyphenol in green tea (Camellia sinensis), possess diverse bioactivity but suffer from poor absorption and rapid metabolism, leading to very limited oral bioavailability. To address these challenges, this study investigated the pharmacokinetics, safety, and tolerability of LipoMicel® GTNAC® (LGT), a novel lipid-based green tea extract formulation co- delivered with N-acetylcysteine (NAC), compared with a standard green tea formulation (SGT) in healthy adults.

METHODS

The study comprised two parts: a randomized, double-blind, crossover pharmacokinetic trial in 16 healthy adults comparing LGT 330 mg with SGT 330 mg and SGT 660 mg, followed by a 30-day open-label, single-arm safety study evaluating LGT 1,320 mg/day in 13 participants.

RESULTS

For EGCG, LGT significantly increased baseline-adjusted systemic exposure compared with dose-matched SGT, producing a 4.2-fold higher iAUC₀-₂₄ (1857 ± 1,479 vs. 443 ± 1,570 ng·h/mL; p = 0.032) and a 3.0-fold higher iCmax (267 ± 235 vs. 88.6 ± 60.0 ng/mL; p = 0.037). No clinically significant adverse events or clinically meaningful changes in blood chemistry were observed during the 30-day safety phase.

CONCLUSION

These findings demonstrate that LGT significantly enhances systemic EGCG exposure while remaining well tolerated for over 30 days in healthy adults. Larger and longer-term studies are warranted to determine whether improved EGCG exposure translates into clinically meaningful health benefits.

CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/, registration number NCT06971536.