4-imino-1-3-diazabicyclo(3.1.0)hexan-2-one and Adenocarcinoma

Imexon is a cyanoaziridine-derived iminopyrrolidone which has synergistic cytotoxicity with gemcitabine. A phase 1 study of the combination demonstrated good tolerance with encouraging clinical activity and thus we conducted this randomized phase II study.. Patients with measurable, metastatic, treatment-naive pancreatic adenocarcinoma were randomized 1:1 to receive gemcitabine at 1000 mg/m days 1, 8, and 15 with either imexon, 875 mg/m or placebo days 1, 8, and 15 every 28 days. The primary endpoint was overall survival. Secondary endpoints included progression-free survival and response rate.. A total of 142 patients were randomized, 72 to the imexon containing arm and 70 to the placebo arm. Patients in the imexon arm received an average of 3.6 cycles (range, 1 to 23) compared with 4.4 (range, 1 to 21) in the placebo arm. There was no increased rate of ≥grade 3 toxicity in the imexon arm. Seven patients had objective responses in the imexon arm (13.7%), whereas 9 did in the placebo arm (17%). In the imexon arm, 23 patients had ≥50% reduction in CA 19-9 from baseline (33%), whereas 22 did in the placebo arm (31.4%). The median progression-free survival was 2.8 months in the imexon arm (95% confidence interval [CI], 2.0-4.1 m) and 3.8 months in the placebo arm (95% CI, 2.2-4.7 m), P=0.504. The median overall survival time in the imexon arm was 5.2 months (95% CI, 4.2-6.7 m) as compared with 6.8 m (95% CI, 4.9-8.5 m) in the placebo arm, P=0.6822.. The combination of imexon and gemcitabine does not result in improved outcome as initial therapy of metastatic pancreatic adenocarcinoma.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Deoxycytidine; Double-Blind Method; Female; Gemcitabine; Hexanones; Humans; Male; Middle Aged; Pancreatic Neoplasms; Progression-Free Survival

Imexon is an aziridine-derived iminopyrrolidone which has synergy with gemcitabine in pancreatic cancer cell lines. Gemcitabine is a standard therapy for pancreatic cancer. We performed a phase I trial of imexon and gemcitabine to evaluate safety, dose-limiting toxicity (DLT), and maximum tolerated dose (MTD) in patients with advanced pancreatic cancer.. Patients with untreated locally advanced or metastatic pancreatic adenocarcinoma received therapy in sequential cohorts on regimen A (n = 19; imexon 200 or 280 mg/m(2) intravenously (IV) over 30 min days 1-5, 15-19 and gemcitabine 800 or 1,000 mg/m(2) IV over 30 min on days 1,8,15 every 28 days) or regimen B (n = 86; imexon 280-1,300 mg/m(2) IV over 30-60 min days 1, 8, and 15 and gemcitabine 1,000 mg/m(2) IV over 30 min on days 1, 8, and 15 every 28 days).. One hundred five patients received 340 treatment cycles (median 2, range 1-16).. median age 63, 61% male, ECOG PS 0/1 50%/50%, 93% metastatic. DLT was abdominal cramping and pain, often with transient, acute diarrhea. Best response was confirmed partial response (PR) in 11.4%, 8.9% unconfirmed PR, and 48.1% with stable disease. There was a dose proportional increase in imexon AUC across the doses tested with terminal half life 69 min at the MTD and no alteration of gemcitabine pharmacokinetics.. The recommended phase II dose of imexon is 875 mg/m(2) with gemcitabine 1,000 mg/m(2). DLT was acute abdominal pain and cramping. Encouraging antitumor responses support further evaluation of this combination in advanced pancreatic cancer.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Antimetabolites, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Area Under Curve; Cohort Studies; Cystine; Deoxycytidine; Dose-Response Relationship, Drug; Female; Gemcitabine; Half-Life; Hexanones; Humans; Male; Middle Aged; Pancreatic Neoplasms; Sulfhydryl Compounds; Tomography, X-Ray Computed