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Irinotecan is a major drug in the treatment of advanced colorectal cancer. Its active form is the SN38 metabolite, which is cleared by the biliary route after glucuronidation by uridine diphosphate-glucuronosyltransferase 1A1 (UGT1A1). UGT1A1 activity exhibits a wide intersubject variability, in part related to UGT1A1 gene polymorphisms. The present review on the impact of the deficient UGT1A1*28 variant on irinotecan efficacy and toxicity was produced by a French joint workgroup comprising the Group of Clinical Onco-pharmacology (GPCO-Unicancer) and the National Pharmacogenetics Network (RNPGx). It clearly emerges that for irinotecan doses at least equal to 180 mg/m(2) , patients homozygous for the UGT1A1*28 allele are at increased risk of developing hematological and/or digestive toxicities. Irinotecan dose reduction is thus recommended in homozygous *28/*28 patients. In addition, this personalized medicine strategy aims to secure high-dose irinotecan administration (≥240 mg/m(2) ) that have proven to be safe in homozygous *1/*1 patients only. The clinical relevance of this test is discussed in terms of treatment efficacy improvement, as increasing the irinotecan dose appears to be safe in patients not bearing a deficient allele. Best execution practices, cost-effectiveness, and result interpretation are discussed with the aim of facilitating the implementation of this analysis in clinical practice. The existence of networks of laboratories performing this test in routine hospital treatment, as in France, offers the prospect of widespread screening, thus guaranteeing equal access to safe treatment and optimized therapy for patients receiving irinotecan-based therapy in advanced colorectal cancer.

Cannabis is a plant that has been used for centuries to relieve a wide range of symptoms. Since the 1960s, interest in medical research into this plant has grown steadily. Already very popular for recreational use, a growing number of consumers not accustomed to using cannabis for psychoactive purposes have begun to use it as an alternative or complement to mainstream pharmaceutical medicines. The principal unsubstantiated or 'social' uses of cannabis are based mainly on data that is at best controversial, but usually not scientifically proven. The aim of this review was to identify the scientific basis and reasons that lead patients with cancer to consume cannabis, and also to identify whether there is a risk of interaction between cannabis and anticancer medicines through drug transporters (P-glycoprotein and other ATP-binding cassette superfamily members) Cytochromes P450 (3A, 1A, 2B, 2C, 2D families…) and glucuronyl transferases.

High-dose methotrexate remains a mainstay in the treatment of acute lymphoblastic leukaemia, osteosarcoma and non-Hodgkin lymphoma. Therapeutic drug monitoring of plasma MTX is important to monitor efficacy and adverse events. The authors aimed at developing a liquid chromatography tandem mass spectrometry (LC-MS/MS) method with online extraction to determine MTX and 7-OH-MTX in plasma for therapeutic drug monitoring. The analysis combined straightforward sample preparation, consisting of protein precipitation with methanol/ZnSO4, with a 4-minute run time consisting of an online enrichment by a flush/back-flush cycle (Poros column, R1/20, 2.1 mm  30 mm) before the second dimension chromatography (Phenomenex Luna 5 mm Phenyl Hexyl, 2 mm  50 mm column). Samples were analysed using an HPLC Agilent 1200 Series and ABSciex API 3200. The electrospray was operated in positive ionization mode monitoring the following mass transitions: m/z 455.11 / 308.3 for MTX, 471.14 / 324.3 for 7-OH-MTX and m/z 459.1 / 312.3 for internal standard (MTX 13 C 2 H 3 ). The method was linear up to 50 mmol L À1 , and intra-day and inter-day quality control CVs were below 8.3% for MTX and 11.71% for 7-OH-MTX. Average recovery was 24% for MTX and 57% for 7-OH-MTX. The lower limit of quantitation was 25 nmol L À1 for the 2 analytes. For MTX and 7-OH-MTX the standard line slope CV percentage was <3% and the slope difference <6%, indicating that our analytical method is almost free from a significant relative matrix effect. Method comparison with the Abbott TDx fluorescent polarization immunoassay (FPIA) showed excellent agreement: LC-MS/MS ¼ 0.0011 + 1.0334 (FPIA). Because of antibody cross-reactivity between DAMPA and MTX, none of the immunoassays can be used after carboxypeptidase administration. The goal of our work was to develop a specific LC-MS/MS method to monitor both MTX and 7-OH-MTX plasma concentrations within the clinically relevant range. It's expected that the LC-MS/MS method for MTX monitoring after carboxypeptidase administration will be very rarely used since it concerns only exceptional cases. Therefore, the geographically balanced distribution of University Hospital able to ensure follow-up of these patients, within 24 hours of collection, can draw a reliable solution for the security of the patients. We develop a fast and reliable LC-MS/MS method for both routine TDM of MTX as in the setting of carboxypeptidase therapy.

Methylone is a synthetic derivative of cathinone. It is sold principally on the Internet in powder form under the name «bath salts». Deaths following consumption are very rare. This report details the first case of a death in France (a 21-year-old man), following ingestion of methylone during an evening with friends. Anoxia was observed at the time of autopsy. Toxicological analyses highlighted a consumption of methylone and cannabis. However, biological analyses showed an absence of ethanol, cocaine, amphetamines, and opiate derivatives. Likewise, no medications were found. High concentrations of methylone were found in the peripheral blood (3.13 mg/L) and in the central blood (6.64 mg/L). Its presence in the gastric contents provides evidence that the substance was taken orally. The dosage of δ9-tetrahydrocannabinol (THC) suggests a recent cannabis consumption (THC 12.9 μg/L, THC-COOH 29.3 μg/L, 11-OH-THC 4.9 μg/L). This case illustrates that the consumption of methylone, which has a reputation of being less «powerful» than ecstasy, is not without its dangers.

Self-injection of high-dose buprenorphine is responsible for well-described complications. In 2011, we have been alerted by unusual but serious cutaneous complication among injection buprenorphine users. A prospective data collection identified 30 cases of necrotic cutaneous lesions after injection of filtered buprenorphine solution, among which 25 cases occurred following injection of buprenorphine generics. The main goal of our study was to put forward particularities that could explain the cutaneous complications, by qualitatively and quantitatively confronting particles present in Subutex and generics solutions. We used the same protocol that injected-buprenorphine users: generic or subutex tablets were crushed in sterile water and filtered through 2 filters commonly used (cotton-pad and sterifilt). Solutions were analyzed by laser granulometry, flow cytometry and scanning electron microscopy. We have highlighted the wide variation of the quantity and the size of the particles present in solution between the two drugs after cotton-pad filtration. The proportion of particles <10 µm is systematically higher in the generic solutions than with Subutex. All of the insoluble particles found in generic solutions contain silica, whereas non- organic element was to be identified in the insoluble particles of Subutex. One skin biopsy obtained from one patient who developed a necrotic lesion after intravenous injection of filtrated solution of buprenorphine generic, shows non-organic elements. Identification of particles in situ enables us to confirm the presence of silica in the biopsy. Actually the monitoring of patient receiving generic of buprenorphine must be strengthened.

♦ OBJECTIVES: Assess the stability of several antibiotics in peritoneal dialysis (PD) solutions under common conditions of use in pediatrics, particularly in automated PD. ♦ METHODS: Amoxicillin, cefazolin, cefepime, ceftazidime, imipenem, cotrimoxazole, tobramycin, vancomycin, and the association of ceftazidime + vancomycin and ceftazidime + tobramycin, were tested in 3 different PD solutions: bicarbonate/lactate solution with 2 glucose concentrations (Physioneal 1.36 and 3.86%; Baxter Healthcare Corporation, Deerfield, IL, USA) and an icodextrin-containing solution (Extraneal; Baxter Healthcare Corporation, Deerfield, IL, USA). Concentrations were those recommended in guidelines for the treatment of peritonitis in pediatrics. Physioneal bags were incubated at 37°C for 24 hours, whereas Extraneal bags were stored 12 hours at room temperature (22 ± 2°C) and then 12 hours at 37°C. Drug concentrations were determined using high performance liquid chromatography (HPLC). Each measure was taken in triplicate. Stability of antibiotics was defined as less than 10% degradation of the drug over time. ♦ RESULTS: Cefazolin, cotrimoxazole, tobramycin, and vancomycin were stable under studied conditions. Ceftazidime was stable 24 hours in icodextrin, 12 hours in Physioneal 1.36% and 6 hours in Physioneal 3.86%. The association of tobramycin or vancomycin did not influence the stability of ceftazidime. Cefepime and amoxicillin were stable 6 h, 4 h, and 8 h in Physioneal 1.36%, 3.86% and Extraneal, respectively. The stability of imipenem was very low: 2 h in Physioneal and 6 h in Extraneal. Moreover, an increasingly yellow coloration was observed with the use of imipenem, whereas no color change or precipitation occurred in other bags. ♦ CONCLUSION: Cefazolin, tobramycin, cotrimoxazole, and vancomycin are stable in PD solutions up to 24 hours and can be administered in the PD bag for the treatment of peritonitis, even in automated PD under studied conditions. However, amoxicillin, cefepime, ceftazidime, and imipenem must be used with caution due to their lack of stability.