PPARA variant rs1800234 had a dose dependent pharmacogenetics impact on the therapeutic response to chiglitazar.

Background: Our objective was to explore the pharmacogenetic impact of three known functional variants in drug target genes and determine whether they can explain the inter-individual variation in therapeutic response.
Methods: In a post hoc analysis of data from randomized controlled clinical trials of chiglitazar, we genotyped 481 Chinese patients with T2DM and investigated the association of variants in PPAR genes with the therapeutic outcome separated by dose using linear regression.
Results: rs1800234, a gain-of-function variant of PPARA, had a dose-dependent pharmacogenetic impact on the therapeutic response to chiglitazar. The C allele was significantly associated with reduced therapeutic response in the 48 mg group, while no significant association was observed in the 32 mg group. In addition, in patients without the C allele, patients treated with 48 mg chiglitazar had a better therapeutic response than those treated with 32 mg chiglitazar. To the contrary, in patients with the C allele, patients treated with 48 mg chiglitazar had a worse therapeutic response than those treated with 32 mg of chiglitazar.
Conclusion: The PPARA variant rs1800234 had a dose-dependent pharmacogenetic impact on the therapeutic response to chiglitazar. It could help explain the absence of a dose effect of chiglitazar and serve as a potential biomarker for the chosen dose of chiglitazar in the future. In addition, our study provided important reference for the design and clinical application of multi-target drugs.