Brivanib Exhibits Potential for Pharmacokinetic Drug–Drug Interactions and the Modulation of Multidrug Resistance through the Inhibition of Human ABCG2 Drug Efflux Transporter and CYP450 Biotransformation Enzymes

Abstract

Brivanib, a promising tyrosine kinase inhibitor, is currently undergoing advanced stages of clinical evaluation for solid tumor therapy. In this work, we investigated possible interactions of this novel drug candidate with ABC drug efflux transporters and cytochrome P450 (CYP450) drug-metabolizing enzymes that participate in cancer multidrug resistance (MDR) and pharmacokinetic drug–drug interactions (DDIs). First, in accumulation experiments with various model substrates, we identified brivanib as an inhibitor of the ABCB1, ABCG2, and ABCC1 transporters. However, in subsequent combination studies employing 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide proliferation assays in both Madin-Darby canine kidney II (MDCKII) and A431 cellular models, only ABCG2 inhibition was revealed to be able to synergistically potentiate mitoxantrone effects. Advantageous to its possible use as MDR antagonist, brivanib’s chemosensitizing properties were not impaired by activity of any of the MDR-associated ABC transporters, as observed in comparative viability assay in the MDCKII cell sublines. In incubation experiments with eight recombinant CYP450s, we found that brivanib potently inhibited CYP2C subfamily members and the CYP2B6 isoform. Finally, in induction studies, we demonstrated that brivanib upregulated ABCB1 and CYP1A2 messenger RNA levels in systemic cell models, although this interaction was not significantly manifested at a functional level. In conclusion, brivanib exhibits potential to cause clinically relevant pharmacokinetic DDIs and act as a modulator of ABCG2-mediated MDR. Our findings might be used as an important background for subsequent in vivo investigations and pave the way for the safe and effective use of brivanib in oncological patients.

Ensartinib (X-396) Effectively Modulates Pharmacokinetic Resistance Mediated by ABCB1 and ABCG2 Drug Efflux Transporters and CYP3A4 Biotransformation Enzyme

“…This dual activity has attracted considerable interest, and combinations of these new drugs with standard cytostatic agents may be powerful therapeutic options for resistant tumors [19,20]. Our research group recently demonstrated that several cyclin-dependent kinase inhibitors exhibit such dual modes of action [21][22][23][24][25][26][27]. We believe that the synergistic combinations identified in our studies could potentially be translated into more efficient and safe therapies for many oncological patients.…”

“…Cellular accumulation assay with hoechst 33342 and calcein AM was performed as described previously [26,27]. Briefly, MDCKII-par, MDCKII-ABCB1, MDCKII-ABCG2, and MDCKII-ABCC1 cells were seeded at densities of 5.0 × 10 4 , 5.0 × 10 4 , 5.5 × 10 4 , and 6.0 × 10 4 cells/well, respectively, on a transparent 96-well plate and grown to full confluence for 24 h under standard conditions.…”

“…The flow-cytometric inhibitory assay with daunorubicin and mitoxantrone was performed with minor modifications as described previously [26,27]. MDCKII-par, MDCKII-ABCB1, MDCKII-ABCG2, and MDCKII-ABCC1 cell lines were seeded at densities of 22.0 × 10 4 , 15.0 × 10 4 , 25.0 × 10 4 , and 22.0 × 10 4 cells/well, respectively, on a 12-well plate and then incubated for 24 h to reach approximately 70-80% confluence.…”

“…CYP inhibitory assay was performed as described previously [26,27]. Experiments were performed with commercial Vivid CYP screening kits containing insect microsomal fractions enriched with a specific human CYP isoform, human CYP reductase, and in some cases, human cytochrome b5.…”

“…A cell-based method using the P450-Glo CYP3A4 Assay and Screening System with Luciferin-IPA together with the CellTiter-Glo Luminescent Cell Viability Assay was used to measure CYP3A4 inhibition in intact HepG2-CYP3A4 cells [27]. HepG2-CYP3A4 cells were seeded on a transparent 96-well plate at a density of 8.0 × 10 4 cells/well and cultured for 24 h. The cells were then washed once with 1× PBS and treated with Opti-MEM solutions of ensartinib (5,10,15, and 25 µM) or a model inhibitor (10 µM ketoconazole).…”