Population Pharmacokinetics of Cefoxitin Administered for Pediatric Cardiac Surgery Prophylaxis.

BACKGROUND: Available data about pharmacokinetics (PK) of antimicrobials administered as surgical prophylaxis to children undergoing cardiac surgery with cardiopulmonary bypass (CPB) showed that drug concentrations during CPB may be supra or subtherapeutic. The aim of this study was to determine the population PK and pharmacodynamic target attainment (PTA) of cefoxitin during pediatric CPB surgery. METHODS: A prospective interventional study was conducted. Cefoxitin (40 mg/kg, up to max 1000 mg) was administered before skin incision. Blood samples were obtained in the operatory room throughout surgery. Population PK, PTA, and safety of cefoxitin were evaluated in neonates, infants, children <10 and >10 years old. RESULTS: Forty patients were enrolled. Cefoxitin levels correlated with time from bolus administration (r = -0.6, P = 0.0001) and, after 240 minutes from bolus, drug values below the target (8 mg/L) were shown. Cefoxitin concentrations were best described by a one-compartment model with first order elimination. A significant relationship was identified between body weight, age, body mass index, and serum creatinine on drug clearance and age, body weight, and body mass index on cefoxitin volume of distribution. The PTA for free drug concentration being above the minimum inhibitory concentration of 8 mg/L for at least 240 minutes was >90% in all age groups except in patients >10 years of age (PTA = 62%). CONCLUSIONS: Cefoxitin PK appears to be significantly influenced by CPB with generally reduced drug clearance. The PTA was adequately achieved in the majority of patients except in patients >10 years old or longer surgeries.

Efficacy and safety of a new device for intravesical thermochemotherapy in non-grade 3 BCG recurrent NMIBC: a phase I-II study.

PURPOSE: We report for the first time the activity and safety of Unithermia(®) (Elmedical Ltd, Hod-Hasharon, Israel), a novel device for administration of MMC-C with hyperthermia (HT), that employs conductive heating, in a series of non-grade 3 non-muscle-invasive bladder cancer (NMIBC) that failed Bacillus Calmette-Guerin (BCG). METHODS: Patients with non-grade 3 NMIBC recurring after at least a full induction course of BCG were eligible for this phase I-II prospective single-arm study. Six weekly instillations with Unithermia(®) were scheduled following complete TUR. Primary end points were treatment safety and response rate (RR), and the latter defined as the absence of any unfavourable outcome at 12 months. Any grade 3 and/or muscle-invasive (T > 1) recurrence was considered disease progression. Kaplan-Meier estimation of the time to recurrence and progression, cancer-specific survival and overall survival was taken as secondary end points. RESULTS: Thirty-four eligible patients entered the study between January 2009 and April 2011. RR was documented in 20/34 (59%). Among the 14/34 (41%) non-responders, four developed G3 disease, one developed carcinoma in situ, and one progressed to muscle-invasive bladder cancer, with an overall 18% progression rate at 1 year. At a median follow-up of 41 months, recurrence and progression rates were 35.3 and 23.5%, respectively. Toxicity did not go beyond grade 2 except in five cases. CONCLUSIONS: Initial experience with MMC-HT with Unithermia(®) showed an interesting activity and safety profile in non-grade 3 NMIBC recurring after BCG, suggesting a role as second-line therapy in this selected subgroup of NMIBC.

Intravesical thermo-chemotherapy based on conductive heat: a first pharmacokinetic study with mitomycin C in superficial transitional cell carcinoma patients.

PURPOSE: To evaluate, for the first time, the mitomycin C (MMC) pharmacokinetics during intravesical hyperthermia treatment based on conductive heat and the stability and recovery of the drug at the end of the instillation period. METHODS: Eleven patients with recurrent intermediate-risk superficial transitional cell carcinoma of the bladder were treated weekly for six cycles with intravesical MMC (40 mg MMC in 50 ml) in local hyperthermia (45 °C) with Unithermia(®) system. Each instillation lasted 45 min, with the solution being replaced after the first 22 min. The MMC recovery at the end of the two instillation period and the plasmatic pharmacokinetics of MMC were evaluated by high-pressure liquid chromatography. RESULTS: Nine patients completed all the six planned cycles, whereas two patients missed the last cycle because of allergic reactions. No other systemic toxicity was observed, and the local toxicities were mild. Median MMC concentration in the instillation residual solution decreases from the initial 0.8 to 0.22 mg/ml for the 0-22-min instillation period and to 0.38 mg/ml for the 22-45-min instillation period; the median percentage of MMC recovered after instillation was 66.2 and 99.6, respectively. In all patients, MMC plasmatic C max resulted considerably lower than the toxic threshold (400 ng/ml). CONCLUSIONS: The MMC is stable during the instillation, and its absorption occurs mainly during the first minutes of the treatment. The plasmatic MMC concentration is always well below the threshold level for myelosuppression, as confirmed by the total lack of hematological toxicity evidenced by the patients. In order to evaluate the efficacy of the treatment performed with UniThermia(®) in reducing the disease recurrence rate in short- and long-term follow-up, we are currently carrying out a clinical multicentric study involving a larger number of patients.

EC-145, a folate-targeted Vinca alkaloid conjugate for the potential treatment of folate receptor-expressing cancers.

EC-145, under development by Endocyte, is a conjugate composed of desacetylvinblastine monohydrazide linked through a peptide spacer to the targeting moiety folic acid, for the potential intravenous treatment of folate receptor-overexpressing tumors, in particular ovarian and lung cancers. In vitro studies demonstrated that EC-145 selectively binds to cells that overexpress the folate receptor, causing dose-dependent cytotoxicity. Furthermore, coincubation of the KB human nasopharyngeal carcinoma cell line with EC-145 and doxorubicin resulted in synergistic antitumor activity. Experiments in mouse tumor xenograft models have confirmed the potency of EC-145 and the curative effects of the drug conjugate were demonstrated in an aggressive lymphoma xenograft model. In a phase I clinical trial in patients with advanced or metastatic solid tumors, adverse events were generally of moderate severity with the most frequent being fatigue, constipation and peripheral sensory neuropathy. Preliminary data from a phase II clinical trial in patients with advanced ovarian cancer demonstrated that third- or fourth-line treatment with EC-145 yielded better disease control than second- or third-line liposomal doxorubicin. Coadministration of EC-145 and liposomal doxorubicin produced a statistically significant increase in progression-free survival over standard therapy in patients with platinum-resistant ovarian cancer. Phase III clinical trials are expected to confirm these promising results.

Administration of reduced glutathione in FOLFOX4 adjuvant treatment for colorectal cancer: effect on oxaliplatin pharmacokinetics, Pt-DNA adduct formation, and neurotoxicity.

Oxaliplatin is a promising drug for cancer therapy and the oxaliplatin/5-fluorouracil/leucovorin (FOLFOX) regimen has become the standard adjuvant treatment for colorectal cancer. However, the oxaliplatin-induced neurotoxicity still represents a clinical problem leading to a discontinuation of the therapy. Many strategies have been proposed in order to manage the neurotoxicity, but their effect on antitumoral efficacy is still unclear. In this study, we investigated the effect of reduced glutathione administration on neurotoxicity, oxaliplatin pharmacokinetics, and platinum-DNA (Pt-DNA) adduct formation in patients affected by colorectal cancer treated with FOLFOX4 adjuvant regimen. Twenty-seven patients were randomized to receive GSH 1500 mg/m or saline solution before oxaliplatin infusion. Evaluation of neurotoxicity, pharmacokinetics of plasmatic total and ultrafiltered Pt, and determination of Pt-DNA adduct formation on white blood cells was performed during the 5th, 9th, and 12th cycles. At the end of all cycles of therapy, the patients in the GSH arm showed a statistically significant reduction of neurotoxicity (P=0.0037) compared with the placebo arm. There were no significant differences in the main pharmacokinetic parameters between the two arms except a lower area under the plasma concentration-time curve and a smaller apparent steady-state volume of distribution (Vss) when GSH was coadministered. This difference can be explained by the natural function of GSH in the detoxification of oxaliplatin and by its ability to remove the Pt bound to plasma proteins. The determination of Pt-DNA adduct formation shows no statistically significant differences between the two arms. In conclusion, this study indicates that coadministration of GSH is an effective strategy to reduce the oxaliplatin-induced neurotoxicity without impairing neither the pharmacokinetics of oxaliplatin, nor the Pt-DNA adduct formation.