Pharmacokinetics and bioequivalence of sunitinib and Sutent^® in Chinese healthy subjects: an open-label, randomized, crossover study

Purpose: The purpose of this study was to examine the pharmacokinetics (PK), bioequivalence and safety of generic sunitinib and its original product Sutent^® in healthy Chinese subjects through a phase-I clinical trial. Methods: The study selected two groups of 24 healthy Chinese subjects in a 1:1 ratio through random allocation. Each participant received either 12.5 mg of sunitinib or Sutent^® per cycle. A total of 15 different time points were employed for blood sample collection during each cycle. Furthermore, a comprehensive assessment of the drugs' safety was consistently maintained throughout the trial. Results: The average adjusted geometric mean ratios (GMR) (90% CI) for the primary PK parameters C_max, AUC_0-t and AUC_0-∞ were 97.04% (93.06%-101.19%), 98.45% (93.27%-103.91%) and 98.22% (93.15%-103.56%), respectively. The adjusted GMRs for essential pharmacokinetic (PK) parameters all met the requirements for bioequivalence, with values within the acceptable range of 80%-125%. In addition, the two drugs showed comparable results for the other PK parameters. These results indicate that the two drugs were bioequivalent. Furthermore, both drugs showed well safety. Conclusion: The research results proved that the PK and safety profiles of sunitinib in healthy Chinese subjects were comparable to those of Sutent^®. These results advocate the clinical application of generic sunitinib as a potential alternative to original product Sutent^® in the treatment of certain medical conditions.