Yiting Hu,1 Na Zhao,1 Haojing Song,1 Jian Zhang,2 Lusha Bi,3 Bo Qiu,1 Yufang Xu,1 Caiyun Jia,1 Wanjun Bai1 

1Department of Pharmacy, Hebei General Hospital, Hebei Key Laboratory of Clinical Pharmacy, Shijiazhuang, People’s Republic of China; 2Department of Gastroenterology and Hepatology, Hebei General Hospital, Shijiazhuang, People’s Republic of China; 3Shijiazhuang Pharmaceutical Group Ouyi Pharmaceutical Co., Ltd., Shijiazhuang, People’s Republic of China

Correspondence: Wanjun Bai, Department of Pharmacy, Hebei General Hospital, Hebei Key Laboratory of Clinical Pharmacy, Shijiazhuang, People’s Republic of China, Tel +86-0311-85988326, Email baiwanjun0311@163.com

Objective: Bioequivalence of palbociclib tablets was evaluated in healthy volunteers under fasting and fed conditions in this study.
Methods: This bioequivalence trial, which randomized subjects to receive palbociclib under fed or fasted conditions, generated these results. High-performance liquid chromatography-mass spectrometry (HPLC-MS) was employed to determine palbociclib concentrations in plasma from collected blood samples. Pharmacokinetic (PK) parameters were calculated using the non-compartmental analysis (NCA) module within Phoenix WinNonlin version 8.2. Statistical analysis of key pharmacokinetic parameters-maximum plasma concentration (Cmax), area under the concentration-time curve from zero to last quantifiable time (AUC0-t), and area under the curve from zero to infinity (AUC0–∞)-was conducted using the bioequivalence (BE) module within WinNonLin. A total of 68 healthy subjects were enrolled and randomized to either a fasted or a fed group. All subjects were randomized into T-R and R-T sequences (T: test formulation; R: reference formulation).
Results: The geometric mean ratios (T/R) of Cmax, AUC0-t and AUC0–∞ of palbociclib in plasma were 97.96%, 96.16%, and 96.02% under fasting conditions; The geometric mean ratios (T/R) of Cmax, AUC0-t and AUC0-∞ of palbociclib in plasma were 95.47%, 96.49%, and 96.36% under fed conditions. All 90% confidence intervals for the geometric mean ratios were contained entirely within the range of 80.00% to 125.00%. Under the fasted and fed conditions, the test preparation and the reference preparation of palbociclib tablets were bioequivalent. Adverse events (AEs) occurred at similar rates in the fasted and fed groups.
Conclusion: The result indicated that the test preparation and the reference preparation of palbociclib tablets were bioequivalent under the fasted and fed conditions. The safety of the two preparations was good.
Clinical Trial Registration: This trial was registered on the Chinese Clinical Trial website (http://www.chinadrugtrials.org.cn/index.html # CTR20220977).

Keywords: bioequivalence, breast cancer, palbociclib, safety, pharmacokinetics