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Purpose: The herbal supplement garlic (Allium sativum) is commonly used by cancer patients. Preclinical studies have shown that allicin, a major component of garlic, may affect cytochrome P450 3A4 (CYP3A4) activity. This study examines the influence of garlic supplementation on the pharmacokinetics of docetaxel, a CYP3A4 substrate. Experimental Design: Women with metastatic breast cancer were treated with docetaxel (30 mg/m2) given weekly for 3 of 4 weeks. Three days after the initial dose of docetaxel, patients received 600 mg of garlic twice daily for 12 consecutive days. Docetaxel pharmacokinetics were assessed during the first three administrations. Results: In 10 evaluable patients, the mean baseline clearance of docetaxel was 30.8 L/h/m2 [95% confidence intervals (95% CI), 16.7-44.9]. Coadministration of garlic reduced mean clearance of docetaxel to 23.7 L/h/m2 (95% CI, 15.5-31.8) and 20.0 L/h/m2 (95% CI, 13.3-26.7) on days 8 and 15, respectively (P = 0.17). Additional pharmacokinetic variables of docetaxel, including peak concentration (P = 0.79), area under the curve (P = 0.36), volume of distribution (P = 0.84), and half-life (P = 0.36), were also not statistically significantly different. The mean area under the curve ratio between day 15 and day 1 was 3.74 in three individuals with the CYP3A5*1A/*1A genotype (all African American) compared with 1.02 in six individuals with the CYP3A5*3C/*3C genotype (all Caucasian). Conclusions: This study indicates that garlic does not significantly affect the disposition of docetaxel. However, it cannot be excluded that garlic decreases the clearance of docetaxel in patients carrying a CYP3A5*1A allele.

Purpose: To determine the maximum tolerated dose, dose-limiting toxicities, and pharmacokinetic characteristics of doxorubicin encapsulated in a low temperature sensitive liposome (LTSL) when given concurrently with local hyperthermia to canine solid tumors.Experimental Design: Privately owned dogs with solid tumors (carcinomas or sarcomas) were treated. The tumors did not involve bone and were located at sites amenable to local hyperthermia. LTSL-doxorubicin was given (0.7-1.0 mg/kg i.v.) over 30 minutes during local tumor hyperthermia in a standard phase I dose escalation study. Three treatments, given 3 weeks apart, were scheduled. Toxicity was monitored for an additional month. Pharmacokinetics were evaluated during the first treatment cycle.Results: Twenty-one patients were enrolled: 18 with sarcomas and 3 with carcinomas. Grade 4 neutropenia and acute death secondary to liver failure, possibly drug related, were the dose-limiting toxicities. The maximum tolerated dose was 0.93 mg/kg. Other toxicities, with the possible exception of renal damage, were consistent with those observed following free doxorubicin administration. Of the 20 dogs that received ≥2 doses of LTSL-doxorubicin, 12 had stable disease, and 6 had a partial response to treatment. Pharmacokinetic variables were more similar to those of free doxorubicin than the marketed liposomal product. Tumor drug concentrations at a dose of 1.0 mg/kg averaged 9.12 ± 6.17 ng/mg tissue.Conclusion: LTSL-doxorubicin offers a novel approach to improving drug delivery to solid tumors. It was well tolerated and resulted in favorable response profiles in these patients. Additional evaluation in human patients is warranted.

Purpose: A phase I trial of intrathecal Spartaject Busulfan (SuperGen, Inc., San Ramon, CA) was conducted in children with neoplastic meningitis following recurrent primary brain tumors to describe toxicities, estimate the maximum tolerated dose (MTD), and document evidence of responses to this agent. Experimental Design: The continuous reassessment method was used to assign cohorts of patients to doses of intrathecal Spartaject Busulfan via an Ommaya reservoir and/or lumbar puncture twice weekly for 2 weeks followed by an assessment of toxicity and response. Patients with stable disease or an objective response continued to receive intrathecal Spartaject Busulfan plus systemic chemotherapy at regular intervals. Cerebrospinal fluid and blood were obtained for pharmacokinetic studies in patients with Ommaya reservoirs after the first dose of intrathecal Spartaject Busulfan. Seven evaluable patients were assigned to the starting dose of 5 mg, two patients to 7.5 mg, three patients to 10 mg, seven patients to 13 mg, and four patients to 17 mg. Results: Between September 2000 and May 2003, 28 patients were enrolled in this study. Twenty-three patients (median age, 8.8 years; range, 2.5-19.5 years) were evaluable for estimating the MTD, and dose-limiting toxicities were observed in three and included grade 3 vomiting (n = 1 at 5 mg), grade 3 headache (n = 1 at 17 mg), and grade 3 arachnoiditis (n = 1 at 17 mg). Pharmacokinetic data showed that post-infusion concentrations of busulfan ranged from 50 to 150 μg/mL and declined to Conclusions: Intrathecal Spartaject Busulfan was well tolerated in children with neoplastic meningitis from brain tumors, and the recommended dose for future phase II studies is 13 mg.

This report investigates relationships between the pharmacokinetics and pharmacodynamics of high-dose alkylators used for the treatment of primary breast cancer. Eighty-five women with primary breast cancer involvingor=10 lymph nodes received four cycles of standard-dose chemotherapy followed by a high-dose regimen consisting of: cyclophosphamide (1875 mg/m(2) once daily x 3), cisplatin (165 mg/m(2) given over 72 h), carmustine (600 mg/m(2)), and stem cell transplantation. Dosages were attenuated in patients whose body weight exceeded their calculated ideal weight by20%. Pharmacokinetics of the high-dose chemotherapeutic agents were evaluated in each patient by collection and analysis of serial blood samples. Area under the concentration time curve (AUC) for cyclophosphamide and carmustine was highly variable (10-fold inter-patient range) with coefficients of variation50%, in contrast to cisplatin exposures (2-fold range; coefficient of variation 12%). The dosing method for overweight patients resulted in significantly lower systemic exposure to cisplatin (P = 0.035). The parent cyclophosphamide clearance on the 1st day of administration was significantly higher in patients who experienced acute cardiac toxicity (n = 5; P = 0.011), whereas carmustine disposition was not found to be different in those developing pulmonary toxicity (n = 25; P = 0.96). Kaplan-Meier analysis (median follow-up of 5.9 years) demonstrated that patients with lower cyclophosphamide AUC (faster parent drug clearance to potentially cytotoxic compounds) survived longer (P = 0.031). Inter-individual differences in the pharmacokinetic disposition of high-dose chemotherapy may explain variability in both response and toxicity. Prospective strategies, which attempt to individualize AUC, should be evaluated in this setting.