Phase I Study of Vorinostat in Combination with Temozolomide in Patients with High-Grade Gliomas: North American Brain Tumor Consortium Study 04-03
Mené sur 59 patients atteints d'un gliome de haut grade, cet essai de phase I évalue un traitement combinant temozolimide et vorinostat, un inhibiteur d'histone déacétylase
Purpose: A phase I, dose-finding study of vorinostat in combination with temozolomide (TMZ) was conducted to determine the maximum tolerated dose (MTD), safety, and pharmacokinetics in patients with high-grade glioma (HGG). Experimental Design: This phase I, dose-finding, investigational study was conducted in two parts. Part 1 was a dose-escalation study of vorinostat in combination with TMZ 150 mg/m2/day x 5 days every 28 days. Part 2 was a dose-escalation study of vorinostat in combination with TMZ 150 mg/m2/day x 5 days of the first cycle and 200 mg/m2/day x 5 days of the subsequent 28-day cycles. Results: In Part 1, the MTD of vorinostat administered on days 1-7 and 15-21 of every 28 day cycle in combination with TMZ was 500 mg daily. Dose-limiting toxicities (DLTs) included grade 3 anorexia, grade 3 ALT, and grade 5 hemorrhage in the setting of grade 4 thrombocytopenia. In Part 2, the MTD of vorinostat on days 1-7 and 15-21 of every 28 day cycle combined with TMZ was 400 mg daily. No DLTs were encountered, but vorinostat dosing could not be escalated further due to thrombocytopenia. The most common serious adverse events were fatigue, lymphopenia, thrombocytopenia, and thromboembolic events. There were no apparent pharmacokinetic interactions between vorinostat and TMZ. Vorinostat treatment resulted in hyperacetylation of histones H3 and H4 in peripheral mononuclear cells. Conclusion: Vorinostat in combination with temozolomide is well-tolerated in patients with HGG. A phase I/II trial of vorinostat with radiotherapy and concomitant TMZ in newly diagnosed glioblastoma is underway.