Figure 1.

In vivo efficacy of PLX51107 and quizartinib in MV4-11 xenograft models. (A) Dose-response relationship of PLX51107 single agent activity after 14-day treatment; (B) MYC gene expression measured pre-dose, 2, 4 and 8 hours after a single 20 mg/kg dose of PLX51107. Two mice were taken down at each time point for the gene expression profiling. (C and D) 20 mg/kg PLX51107 were combined with low-dose (1 mg/kg) quizartinib in a continuous (25-day) dosing regimen. Treatment of MV4-11 xenografts with quizartinib and/or PLX51107 results in tumor control, particularly in the combination arm. (D) 5 of 7 mice treated with the combination had no measurable tumor on day 14. (E and F) 20 mg/kg PLX51107 was combined with high-dose (5 mg/kg) quizar tinib for 5 days. On day 49, following regrowth of tumors in the short-term single-agent quizartinib arm, treatment was restarted with 20 mg/kg PLX51107 plus 5 mg/kg quizartinib to monitor further tumor control.