Enzastaurin plus temozolomide with radiation therapy in glioblastoma multiforme: a phase I study.
We conducted a phase I study to determine the safety and recommended phase II dose of enzastaurin (oral inhibitor of the protein kinase C-beta [PKCbeta] and the PI3K/AKT pathways) when given in combination with radiation therapy (RT) plus temozolomide to patients with newly diagnosed glioblastoma multiforme or gliosarcoma. Patients with Karnofsky performance status > or =60 and no enzyme-inducing anti-epileptic drugs received RT (60 Gy) over 6 weeks, concurrently with temozolomide (75 mg/m(2) daily) followed by adjuvant temozolomide (200 mg/m(2)) for 5 days/28-d cycle. Enzastaurin was given once daily during RT and adjuvantly with temozolomide; the starting dose of 250 mg/d was escalated to 500 mg/d if < or =1/6 patients had dose-limiting toxicity (DLT) during RT and the first adjuvant cycle. Patients continued treatment for 12 adjuvant cycles unless disease progression or unacceptable toxicity occurred. Twelve patients enrolled. There was no DLT in the first 6 patients treated with 250 mg enzastaurin. At 500 mg, 2 of 6 patients experienced a DLT (1 Grade 4 and 1 Grade 3 thrombocytopenia). The patient with Grade 3 DLT recovered to Grade <1 within 28 days and adjuvant temozolomide and enzastaurin was reinitiated with dose reductions. The other patient recovered to Grade <1 toxicity after 28 days and did not restart treatment. Enzastaurin 250 mg/d given concomitantly with RT and temozolomide and adjuvantly with temozolomide was well tolerated and is the recommended phase II dose. The proceeding phase II trial has finished accrual and results will be reported in 2009.
Department of Neurological Surgery, University of California San Francisco, 400 Parnassus Avenue, A808, San Francisco, CA 94143-0350, USA. butowski@neurosurg.ucsf.edu
Nicholas
N
Butowski
Susan M
SM
Chang
Kathleen R
KR
Lamborn
Mei Yin
MY
Polley
R
R
Parvataneni
Maria
M
Hristova-Kazmierski
Luna
L
Musib
Steven J
SJ
Nicol
Donald E
DE
Thornton
Michael D
MD
Prados
D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage*; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy*; D015331:Cohort Studies; D003131:Combined Modality Therapy; D003606:Dacarbazine / Q000008:administration & dosage / Q000031:analogs & derivatives; D005260:Female; D005909:Glioblastoma / Q000188:drug therapy* / Q000532:radiotherapy*; D006801:Humans; D007211:Indoles / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D000077204:Temozolomide; D055815:Young Adult
D007211:Indoles; D003606:Dacarbazine; C504878:enzastaurin; D000077204:Temozolomide