Perentesis, John P.

AbstractBackgroundThe c‐Met receptor tyrosine kinase is dysregulated in many pediatric cancers. Tivantinib is an oral small molecule that inhibits the c‐Met receptor tyrosine kinase. A phase 1 and pharmacokinetic (PK) trial evaluating tivantinib was conducted in children with relapsed/refractory solid tumors.MethodsOral tivantinib capsules were administered twice daily with food, continuously in 28‐day cycles. Dose levels 170, 200, and 240 mg/m2/dose were evaluated using a rolling‐six design (Part A). In Part B, subjects received tivantinib powder sprinkled on food at the recommended phase 2 dose (RP2D) from Part A. PK, CYP2C19 genotyping, and baseline tumor tissue c‐Met expression were analyzed.ResultsThirty‐six patients were enrolled: 20 in Part A, 6 in a PK expansion cohort, and 10 in Part B. Fifteen patients had primary central nervous system tumors and 21 had solid tumors. In Part A, there were no dose‐limiting toxicities. One grade 4 intracranial hemorrhage occurred in a patient with a progressive brain tumor in the expanded PK cohort (240 mg/m2). PK analysis showed marked interpatient variability (20‐fold) in the Cmax and AUC0‐8h across all dose levels. Sprinkling tivantinib powder over food did not alter exposure. Membranous and total c‐Met expression was moderate (2), low (4), or not detected (26). Two patients had stable disease as the best response.ConclusionsThe RP2D of tivantinib given with food in children with refractory solid tumors is 240 mg/m2/dose. PK of tivantinib in children demonstrated high variability. Objective responses were not observed in this phase 1 trial.

Abstract Purpose: To determine the MTD, dose-limiting toxicities (DLT), pharmacokinetics, and biologic effects of cixutumumab administered in combination with temsirolimus to children with refractory solid tumors. Experimental Design: Cixutumumab and temsirolimus were administered intravenously once every 7 days in 28-day cycles. Pharmacokinetic and biology studies, including assessment of mTOR downstream targets in peripheral blood mononuclear cells, were performed during the first cycle. Results: Thirty-nine patients, median age 11.8 years (range, 1–21.5), with recurrent solid or central nervous system tumors were enrolled, of whom 33 were fully assessable for toxicity. There were four dose levels, which included two dose reductions and a subsequent intermediated dose escalation: (i) IMC-A12 6 mg/kg, temsirolimus 15 mg/m2; (ii) IMC-A12 6 mg/kg, temsirolimus 10 mg/m2; (iii) IMC-A12 4 mg/kg, temsirolimus 8 mg/m2; and (iv) IMC-A12 6 mg/kg, temsirolimus 8 mg/m2. Mucositis was the predominant DLT. Other DLTs included hypercholesterolemia, fatigue, thrombocytopenia, and increased alanine aminotransferase. Target inhibition (decreased S6K1 and PAkt) in peripheral blood mononuclear cells was noted at all dose levels. Marked interpatient variability in temsirolimus pharmacokinetic parameters was noted. At 8 mg/m2, the median temsirolimus AUC was 2,946 ng • h/mL (range, 937–5,536) with a median sirolimus AUC of 767 ng • h/mL (range, 245–3,675). Conclusions: The recommended pediatric phase II doses for the combination of cixutumumab and temsirolimus are 6 mg/kg and 8 mg/m2, respectively. Clin Cancer Res; 21(7); 1558–65. ©2014 AACR.

BackgroundWe report results of a phase I trial designed to estimate the maximum tolerated dose (MTD), describe dose‐limiting toxicities (DLT), and characterize the pharmacokinetic profile of MK‐2206, an AKT inhibitor, in children with refractory or recurrent malignancies.ProcedureMK‐2206 was administered either every other day (Schedule 1), or once a week (Schedule 2) in a 28‐day cycle. Dose escalations in increments of ∼30% were independently made in each part using the rolling‐six design. Serial pharmacokinetic (PK) studies were obtained. Biological studies include analysis of PI3K/PTEN/AKT‐cell signaling pathway in pre and post‐therapy in PBMC and in tumors at diagnosis or recurrence.ResultsFifty patients (26 males, median age 12.6 years [range, 3.1–21.9]) with malignant glioma (16), ependymoma (4), hepatocellular carcinoma (3), gliomatosis cereberi (2), or other tumors (22) were enrolled; 40 were fully evaluable for toxicity (Schedule 1, n = 23; Schedule 2, n = 17). Schedule 1 DLTs included: grade 3 dehydration in 1/6 patients at 28 mg/m2; grade 4 hyperglycemia and neutropenia in 1/6 patients at 45 mg/m2; and grade 3 rash in 3/6 patients at dose level 4 (58 mg/m2). Schedule 2 DLTs included: grade 3 alkaline phosphatase in 1/6 patients at 90 mg/m2; grade 3 rash in 1/6 patients at 120 mg/m2; and grade 3 rash in 2/6 patients at 155 mg/m2.ConclusionsThe recommended pediatric phase 2 dose of MK‐2206 is 45 mg/m2/dose every other day or 120 mg/m2/dose weekly. PK appeared linear over the dose range studied. Pediatr Blood Cancer 2014;61:1246–1251. © 2014 Wiley Periodicals, Inc.