Table S1. Summary of most common drug-related AEs, by dosing schedule; Table S2. Summary of pharmacokinetic parameters of TAK-117 on day 1 of cycle 1 across different dosing schedules (pharmacokinetics-evaluable population); Table S3. Summary statistics of TAK-117: multiple-dose pharmacokinetic parameters across different schedules (pharmacokinetics-evaluable population).
Funding
Millennium Pharmaceuticals, Inc., Cambridge, MA, USA
ARTICLE ABSTRACT
Purpose: To evaluate the safety, MTD, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of TAK-117 (MLN1117/INK1117), an investigational PI3Kα-selective inhibitor, in patients with advanced solid tumors.Experimental Design: Seventy-one patients received oral TAK-117 once daily [100–300 mg (n = 24)] or 3 days per week [Monday–Wednesday–Friday (MWF), 200–1,200 mg (n = 27); Monday–Tuesday–Wednesday (MTuW), 200–900 mg (n = 20)], in 21-day cycles. Dose escalation proceeded via a 3 + 3 design.Results: TAK-117 once-daily dosing was associated with dose-limiting grade ≥3 alanine/aspartate aminotransferase (ALT/AST) elevations, resulting in a narrow range of tolerable doses (100–150 mg once daily). With MWF/MTuW dosing, no dose-limiting ALT/AST elevations occurred until the MTD of 900 mg; total weekly dose was 2.6-fold that of 150 mg once daily. Drug-related grade ≥3 adverse events occurred in 25%/22%/35% (including hyperglycemia in 0%/7%/15%) of once-daily/MWF/MTuW patients. TAK-117 (100–1,200 mg) exhibited moderately fast oral absorption, a generally dose proportional increase in exposure, and plasma half-life of approximately 11 hours. Total weekly exposures with 900 mg MWF/MTuW dosing were approximately 4 times greater than with 150 mg once daily. Skin pS6 expression was suppressed at ≥200 mg. There were 3/1/0 partial responses (once daily/MWF/MTuW) and 5/7/5 patients had stable disease lasting ≥3 months (all PIK3CA mutated).Conclusions: Intermittent dosing of TAK-117 had an acceptable safety profile and enabled higher doses and total weekly exposures versus once-daily dosing. Although the potential for TAK-117 as single-agent therapy appears limited, further evaluation in combination approaches for advanced solid tumors is warranted. Clin Cancer Res; 23(17); 5015–23. ©2017 AACR.
