Evaluation of Drug-Drug Interaction between Suraxavir Marboxil (GP681) and Itraconazole, and Assessment of the Impact of Gene Polymorphism

Mai Han ¹ Gang Cui ^1* Yan Zhao ^2* Xianbo Zuo ¹ Xiaoxue Wang ^1* Xin Zhang ^1* Na Mi ^1* Jiangli Jin ¹ Chunyan Xiao ^1* Jing Wang ^1* Wei Wu ^1* Yajuan Li ^2* Jintong Li ^1*

• ¹ China-Japan Friendship Hospital, Beijing, China
• ² Jiangxi Qingfeng Pharmaceutical Co. Ltd, Ganzhou, Jiangxi Province, China

Suraxavir Marboxil (GP681) is a prodrug metabolized to GP1707D07, which inhibits influenza viral replication by targeting cap-dependent endonuclease through a single oral dose. This study assesses the in vivo drug-drug interaction (DDI) potential between GP681 (including its major metabolite GP1707D07, a substrate of CYP3A4) and itraconazole in healthy Chinese subjects, along with the safety profiles during co-administration. Additionally, it evaluates the impact of CYP1A2, CYP2C19, and CYP3A4 gene polymorphisms on GP1707D07 metabolism. The study enrolled twelve healthy adult subjects to receive the treatments consisting of GP681 monotherapy and GP681-itraconazole co-administration in a fixed-sequence. Single nucleotide polymorphisms (SNPs) in CYP gene loci were also analyzed. Co-administration of itraconazole increased the GP1707D07 AUC0-∞ by about 2.5 folds and Cmax by about 1.4 folds compared with GP681 administered alone. Differences in system exposure were more pronounced during the terminal elimination phase than the early stage of GP1707D07 metabolism. No significant increase in adverse events was observed during co-administration. Using random forest algorithm, we estimated effects of cytochrome P450 enzymes followed the order of CYP 3A4 > CYP 1A2 > CYP 2C19. We also hypothesized CYP 3A4 rs4646437 A>G, CYP 3A4 rs2246709 G>A, and CYP 2C19 rs12768009 A>G to be mutations that enhanced enzyme activity, while CYP1A2 rs762551 C>A weakened it. The pharmacokinetic changes of GP1707D07 during itraconazole co-administration are insufficient to warrant clinical action. Random forest algorithm enhances the understanding of pharmacogenetic variants involved in GP1707D07 metabolism and may serve as a potent tool for assessing gene polymorphism data in small clinical samples. Clinical Trial Registration: clinicaltrials.gov, identifier NCT05789342.