Amprenavir is an HIV-1 protease inhibitor which is hepatically metabolized (>80%) with a low renal elimination. It has thus been suggested that no dosage adjustment is necessary in patients with renal dysfunction. However, no data are available on the pharmacokinetics of amprenavir in patients with renal insufficiency. We report on the pharmacokinetics of amprenavir in two HIV patients with severe and end-stage renal insufficiency. Amprenavir pharmacokinetics did not differ in our patients as compared with normal renal function subjects. Furthermore, amprenavir was not dialysable (FHD<25%). As a result, the drug may be administered at its normal dose in patients with renal failure, even when severe. In dialysis patients, amprenavir may be administered before or after the session.

Background: Retinoblastoma is the most common malignant intraocular tumor in children. The current treatment gives a good vital prognostic but there are several drawbacks to the arsenal of "classical antitumoral" therapies. Photodynamic therapy (PDT) could be an exciting non-toxic and non-mutagenic alternative protocol.Method: In this paper, we report about the screening of the in vitro photocytotoxicity of hydrophenylporphyrins and chlorins and their glycoconjugated derivatives in a human retinoblastoma cell line (Y79) and for comparison in a colorectal adenocarcinoma cell line (HT29).Results: Despite lower photodynamic activity than that observed for hydroxylated photosensitizers, in particular Foscan (R) glycoconjugated derivatives display phototoxicity (IC50 2.4-0.05 mu M +/- 10%) against Y79 cells with examples of significant intrinsic cytotoxicity. Amongst them the triglucosyl porphyrin 10 is highly photocytotoxic (IC50 0.90 mu M +/- 10%) but is fully devoid of cytotoxicity (IC50 > 15 mu M). The photoactivity is highly modulated by the presence of a diethyleneglycol spacer between the chromophore and the glycoside (compounds 14-17, IC50 0.5, 0.6, 0.05 and 0.35 mu M +/- 10%) and by the anomeric configuration of the sugar (compound 15 and 17, IC50 0.6 and 0.05 mu M +/- 10% respectively). One of the main problems for the use of Foscan is its poor solubility which might be improved by glycoconjugation. Moreover Foscan has been shown to induce necrosis after PDT leading to a possible ulceration of surrounding tissues unsuitable for a conservative treatment. A preferential mitochondrial subcellular localization which has been previously reported for some glycoconjugated photosensitizers could enhance the contribution of apoptosis process.Conclusion: Tri-alpha-O-galactosyl porphyrin 16 is a better candidate than Foscan (R) for a clinical application of PDT for a conservative therapy of retinoblastoma. (C) 2007 Elsevier B.V. All rights reserved.

Amprenavir is an HIV-1 protease inhibitor which is hepatically metabolized (> 80%) with a low renal elimination. It has thus been suggested that no dosage adjustment is necessary in patients with renal dysfunction. However, no data are available on the pharmacokinetics of amprenavir in patients with renal insufficiency. We report on the pharmacokinetics of amprenavir in two HIV patients with severe and end-stage renal insufficiency. Amprenavir pharmacokinetics did not differ in our patients as compared with normal renal function subjects. Furthermore, amprenavir was not dialysable (FHD < 25%). As a result, the drug may be administered at its normal dose in patients with renal failure, even when severe. In dialysis patients, amprenavir may be administered before or after the session. (c) 2007 Elsevier Masson SAS. Tous droits reserves.

Photodynamic therapy (PDT) is emerging as a new strategy for the conservative treatment of hereditary retinoblastoma. The glycoconjugated porphyrins TPP(p-Deg-O-alpha-GalOH)(3), TPP(p-Deg-O-beta-GalOH)(3), TPP(p-Deg-O-alpha-ManOH)(3), and their S-analogues were synthesized to obtain efficient photosensitizers with some retinoblastoma cell affinity. In these systems, a sugar motif and porphyrin core were linked by a diethylene glycol spacer (Deg). Cellular uptake, localization, and photoactivity have been examined in human retinoblastoma cells (Y79). After preincubation with corresponding glycosylated albumin, the uptake of TPP(p-Deg-O-beta-GalOH)(3) and TPP(p-Deg-O-alpha-ManOH)(3) was 40-45% inhibited, indicating a possible cell-sugar-receptor saturation. High photoactivity was observed for the two alpha-galacto/manno porphyrins 8 and 10 (LD(50) = 0.05 and 0.35 muM, respectively) at 514 nm and low fluence (1 J/cm(2)). Analysis by MALDI-TOF mass spectrometry only indicated a small metabolic cleavage of the O-glycoconjugates and a good stability of the S-glycoside porphyrins. On the basis of these in vitro data, TPP(p-Deg-O-alpha-GalOH)(3) and TPP(p-Deg-O-alpha-ManOH)(3) were selected for in vivo studies.

Cyclophosphamide is an alkylating agent widely used from cancer chemotherapy to immunotherapy purposes. In paediatrics oncology, oral cyclophosphamide prescribed at low dosages for a long time treatment is currently investigated. This treatment is a putative well tolerated regimen for children treated for a wide variety of recurrent solid tumours. For these purposes, new oral formulations more convenient for children than cyclophosphamide 50 mg tablets are needed. Thus, we present a rapid method for the assay of cyclophosphamide in various pharmaceutical preparations using high-performance thin-layer chromatography (HPTLC) and derivatization with phosphomolybdic acid. This method is accurate and precise and allows quantitation of cyclophosphamide in aqueous solutions from 400 to 1200 μg/mL. It is suitable for quantitation and stability studies of cyclophosphamide in pharmaceutical products, i.e. capsules and infusion bags prepared in a hospital pharmacy. According to pharmaceutical guidelines, we demonstrated that low dose cyclophosphamide capsules, extemporaneously prepared for children, are stable at least for 70 days.

Morphine and meperidine in Patient-Controlled Analgesic devices are commonly used to treat chronic pain patients. These devices deliver a programmed amount of drug and allow self-administration by the patient depending on the pain. In our department of pharmacy, 300 devices were manufactured in 2003. The aim of this study was to assess their shelf-life. The devices were filled aseptically and without preservatives with 1 and 40 mg/ml morphine solution and 5 and 20 mg/ml meperidine and stored over 30 days at room temperature and protected from light. Culture assay of the solutions showed that they remained sterile for 30 days. No turbidity of any solutions from samples collected twice a week was noticed. pH and osmolarity remained constant. Drug concentrations were determined using stability indicating HPLC method, as we showed that degradation products can be separated from the drugs. Little loss of meperidine occurred within 21 days (<5%) and morphine concentration, which increased, because of solvent evaporation, remained lower than 5% within 21 days but increased up to 10% after 30 days. No traces of degradation products (pseudomorphine or pethidic acid) were detected. The physicochemical and microbiological stability of morphine and meperidine hydrochlorides stored in such devices has been established for 21 days at room temperature and protected from light.

Morphine and meperidine in Patient-Controlled Analgesic devices are commonly used to treat chronic pain patients. These devices deliver a programmed amount of drug and allow self-administration by the patient depending on the pain. In our department of pharmacy, 300 devices were manufactured in 2003. The aim of this study was to assess their shelf-life. The devices were filled aseptically and without preservatives with I and 40 mg/ml morphine solution and 5 and 20 mg/ml meperidine and stored over 30 days at room temperature and protected from light. Culture assay of the solutions showed that they remained sterile for 30 days. No turbidity of any solutions from samples collected twice a week was noticed. pH and osmolarity remained constant. Drug concentrations were determined using stability indicating HPLC method, as we showed that degradation products can be separated from the drugs. Little loss of meperidine occured within 21 days (<5%) and morphine concentration, which increased, because of solvent evaporation, remained lower than 5% within 21 days but increased up to 10% after 30 days. No traces of degradation products (pseudomorphine or pethidic acid) were detected. The physicochemical and microbiological stability of morphine and meperidine hydrochlorides stored in such devices has been established for 21 days at room temperature and protected from light. 2004 Elsevier SAS. Tons droits reserves.

Asymmetrical glycoconjugated tetrapyrrolic macrocycles are under study as efficient sensitizers for photodynamic therapy (PDT). In this context, tri(meta-O-β-glucopyranosyloxyphenyl)chlorin [TPC(m-O-Glu)3] 2a/3a was found to be four times more photoactive in vitro than Foscan®. In a further study of this interesting glycoconjugate, its metabolism by cellular glycosidases in HT29 cells has to be explored. Cellular extracts of HT29 cells incubated with TPC(m-O-Glu)3 (24 h, 6 μM) were analyzed by MALDI-TOF mass spectrometry and high performance liquid chromatography (HPLC). In MALDI-TOF mass spectra, the presence of compounds distinct from TPC(m-O-Glu)3 (m/z 1151) were observed at m/z 989, 827 and 665 corresponding to the loss of one, two or three glucose units (162 u) and were be ascribed to TPC(m-OH)(m-O-Glu)2 2/3b,b′,b″, TPC(m-OH)2(m-O-Glu) 2/3c,c′,c″ and TPC(m-OH)3 isomers 2d/3d, respectively. The porphyrins resulting from chlorin oxidation TPP(m-O-Glu)3 4a, TPP(m-OH)(m-O-Glu)2 4b,b″, TPP(m-OH)2(m-O-Glu) 4c,c″ and TPP(m-OH)3 4d were also observed. The HPLC profile (λanal.=420 nm) showed eight peaks consistent with mass spectra. The kinetics of deglucosylation was studied from HPLC profiles between 1 and 48 h incubation. The concentration of triglucoconjugated and diglucoconjugated molecules was maximum around 3 and 8 h incubation, respectively, whereas, totally deglucosylated species appeared only after incubation for more than 10 h. The fully deglycosylated porphyrin TPP(m-OH)3 is the final metabolite, being observed at a concentration 15 times higher than that of the remaining TPC(m-O-Glu)3 2a/3a. Compared to the photobiological activity of the parent molecule [TPC(m-O-Glu)3], a three times higher TPP(m-OH)3 concentration was necessary to observe a similar in vitro photoactivity.

Glucoconjugated tri and tetra(meta-hydroxyphenyl)chlorins have been synthesized in order to explore how glucoconjugation of the macrocycle affects the photoactivity of the molecule. Internalization processes, photosensitizing efficacy of TPC(m-O-GluOH)3 and TPC(m-O-GluOH)4, in HT29 human adenocarcinoma cells have been compared to those of tetra(meta-hydroxyphenyl) chlorin (m-THPC, Foscan®). The tetra glucoconjugated chlorin, TPC(m-O-GluOH)4, was found to be poorly internalized and weakly photoactive. In contrast, the asymmetric and more amphiphilic compound TPC(m-O-GluOH)3, exhibited superior phototoxicity compared to m-THPC. Drug concentration, temperature and sodium azide effects indicated that TPC(m-O-GluOH)3 internalization partly proceeds via an active receptor-mediated endocytosis mechanism. Cellular uptake appeared as a saturable process and remained 30% lower than for mTHPC. However, a maximum phototoxicity in HT29 cells (survival fraction of 2±0.6%) were observed for concentration as low as 2μM. A 4-fold higher concentration of m-THPC was necessary to observe the same level of photoactivity. This higher phototoxicity has been correlated to a greater mitochondrial affinity. On the basis of these results, work is in progress to further evaluate the potential of glycosylated chlorins in photodynamic therapy (PDT).

meta-Tetra(hydroxyphenyl)chlorin (mTHPC), a second generation photosensitizer used in photodynamic therapy (PDT), was incorporated into long circulating carriers with the aim of improving the tumor selectivity by limiting the reticuloendothelial system (RES) uptake. Biodistribution of mTHPC (0.06 mg kg−1) was studied directly in nude mice bearing HT29 human tumor by optical fiber fluorimetry and tissue drug contents were determined by HPLC after extraction. The drug was incorporated in the oily core of nanocapsules surrounded by poly(d,l lactic acid) (PLA NCs), PLA grafted with polyethylene glycol (PLA-PEG) or PLA coated with poloxamer 188 (polox PLA). Compared to PLA NCs, incorporation of mTHPC in surface-modified nanocapsules resulted in strong modifications of the drug biodistribution and tumoral retention with a three-fold increase of drug level as early as 24 h post-administration. A reduced liver uptake was observed at early times post-administration indicating that surface-modified NCs are effective in limiting the RES uptake and could be potential carriers to enhance the therapeutic ratio of lipophilic photosensitizers. Furthermore, in situ fluorescence measurements and concentration data were found in broad agreement showing that optical fiber fluorimetry is a very sensitive method that can be used to follow the biodistribution of fluorescent drugs in real-time.

Nefopam (NEF) and desmethyl-nefopam (DMN) were assayed simultaneously in plasma, globule and urine samples using imipramine as internal standard. A liquid-liquid extraction procedure was coupled with a reverse phase high-performance liquid chromatography system. This system requires a mobile phase containing buffer (15 mM KH(2)PO(4) with 5 mM octane sulfonic acid: pH 3.7) and acetonitrile (77:33, v/v) through (flow rate=1.5 ml/min) a C(18) Symmetry column (150x4.6 I.D., 5 micrometer particle size: Waters) and a UV detector set at 210 nm. Internal standard was added to 1 ml of plasma or globule sample or 0.5 ml of urine sample, prior to the extraction under alkaline ambiance with n-hexane. The limits of quantification were 1 and 2 ng/ml for both molecules in plasma and globule, respectively; 5 and 10 ng/ml for NEF and DMN in urine, respectively. The method proved to be accurate and precise: the relative error at three concentrations ranged from -13.0 to +12.3% of the nominal concentration for all molecule and biological fluid; the within-day and between-day precision (relative standard deviation %) ranged from 1.0 to 10.1% for all the molecules and biological fluids. The method was linear between 1 and 60 ng/ml for both molecules in the plasma; 2 and 25 ng/ml for both molecules in the globule; 25 and 250 ng/ml for NEF and 50 and 500 ng/ml for DMN in the urine: correlation coefficients of calibration curves (determined by least-squares regression) of each molecule were higher than 0.992 whatever the biological fluid and during the pre-study and in-study validations. This method was successfully applied to a bio-availability study of NEF in healthy subjects.