Phase I dose escalation study of TG02 in patients with advanced hematologic malignancies.

Abstract

6577 Background: TG02 is a novel multikinase inhibitor with a unique spectrum of activity, targeting both the cell cycle regulatory cyclin-dependent kinases (CDKs) 1 and 2 and the transcriptional regulators CDKs 7 and 9. TG02 also inhibits the emerging oncogenic MAPK ERK5 and the DNA damage response mediator CDK5. TG02 kills primary blasts from a variety of hematologic cancers and is curative in the MV4-11 model of FLT3-mutant AML. Methods: This is a first-in-man,single arm, open label, phase I dose escalation trial. The primary endpoints are dose-limiting toxicity (DLT), maximally tolerated dose (MTD ) and recommended phase 2 dose (RP2D). Patients (pts) ≥ 18 years with advanced hematological malignancies or newly diagnosed AML pts ≥ 65 years unfit for intensive therapy were enrolled onto daily (A) and intermittent (B, 5 days on 2 days off X 2 weeks) schedules. Pts had acceptable organ function and ECOG PS 1-2. Definition of DLT was G3-4 AST or ALT ≥7 days, G4 AST or ALT, G4 hyperbilirubinemia, any other NCI CTC G3-4 events not due to underlying disease. Dose levels on arm A were 10mg to 70mg and 15mg-150 mg on arm B. Results: Forty-five pts have received at least one dose of study drug. Median age was 66 years (range, 37-87) and 80% were ECOG 0-1. Disease types enrolled included: AML (80%), high-risk MDS (22%), and CML-BC (3%). The median number of previous regimens was 3 (range, 1-12). The MTD on arm A was defined at 50 mg daily based on 2 DLTs at the 70mg dose level (G4 hyperbilirubinemia, G4 fatigue). Enrollment to arm B has competed dose levels 15 (N=3), 30 (N=3), 50 (N=3), 70 (N=3), 100mg (N=3), and enrollment at 150mg is ongoing without DLT to date. Common drug related adverse events were nausea (42%), vomiting (23%), fatigue (18%), decreased appetite (15%), constipation and diarrhea (13% each). Preliminary PK demonstrated dose proportional increases in exposure and a T1/2 , supporting once daily dosing. Conclusions: The MTD for TG02 has been determined for the daily schedule at 50mg. Enrollment continues on the intermittent schedule. Schedules of every other day and week on/week off dosing will also be evaluated.