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1.
Pharmaceutics ; 15(12)2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38140005

RESUMEN

BACKGROUND: Temozolomide (TMZ) oral suspension (Ped-TMZ, KIZFIZO®) is being developed for the treatment of relapsed or refractory neuroblastoma, a rare cancer affecting infants and young children. The study assessed the safety and the bioequivalence of this novel pediatric formulation with existing TMZ oral capsules. METHODS: In vitro dissolution profiles and the bioequivalence were evaluated following the European Medicines Agency "Guidelines on the investigation of Bioequivalence". The phase I, multicenter, randomized, open-label, crossover, single-dose bioequivalence study enrolled 36 adult patients with glioblastoma multiforme or lower-grade glioma. Each patient received 200 mg/m2 Ped-TMZ suspension and TMZ capsules (Temodal®) on 2 consecutive days, with the order being randomly assigned. Fourteen blood samples were collected up to 10 h post-dosing. Bioequivalence was assessed by comparing the 90% confidence interval for the ratio of the geometric means of maximum TMZ plasma concentration (Cmax) and the area under the curve (AUCt). Other endpoints included further pharmacokinetic parameters and safety. RESULTS: Both formulations exhibited a fast in vitro dissolution profile with more than 85% of TMZ dissolved within 15 min. For the bioequivalence study, thirty patients completed the trial as per the protocol. The ratio of Ped-TMZ/TMZ capsule geometric means (90% CI) for AUCt and Cmax were 97.18% (95.05-99.35%) and 107.62% (98.07-118.09%), respectively, i.e., within the 80-125% bioequivalence limits. No buccal toxicity was associated with Ped-TMZ liquid formulation. CONCLUSIONS: This study showed that Ped-TMZ oral suspension and TMZ oral capsule treatment are immediate release and bioequivalent medicines. There were also no unexpected safety signals or local toxicity (funded by ORPHELIA Pharma; ClinicalTrials.gov number, NCT04467346).

2.
Pharmaceutics ; 15(12)2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38140052

RESUMEN

Temozolomide (TMZ) is part of the therapeutic armamentarium used in managing pediatric cancers; however, available oral forms (capsules) are not adapted for use in children. Our aim was to assess the dose accuracy and stability of TMZ using capsule contents mixed with food compared with a novel, ready-to-use liquid formulation specifically developed for children (Ped-TMZ, brand name KIZFIZO). Dose accuracy and TMZ stability testing were performed with TMZ capsule contents (90 mg) mixed with food vehicles (apple juice, apple sauce, cream, milk, and mashed potatoes) and compared to an equivalent dose of Ped-TMZ. Acceptance criteria were predefined for TMZ (95.0-105.0%) and its degradation product amino-imidazole-carboxamide (AIC; <1%) content. The delivered dose was significantly higher using Ped-TMZ (96.6 ± 1.2%) and within the predefined criteria for TMZ content, whereas it was systematically under the lower specifications of 95% using capsule-derived preparations with apple juice (91.0 ± 1.5%) and apple sauce (91.6 ± 1.4%), respectively (p < 0.0001). In chemical stability tests, the four food vehicles (apple sauce, cream, milk, mashed potatoes) had a significant effect on TMZ stability (p = 0.0042), and the AIC significantly increased with time in three of the four vehicles (p < 0.0001). Only 1/72 of preparations from capsules met the predefined acceptance criteria, whereas Ped-TMZ showed no TMZ loss, and the AIC remained within specifications. In conclusion, mixing TMZ capsule content with food may result in significant underexposure, possibly even greater in routine practice, as complete food intake by the child is unlikely.

3.
Pharmaceuticals (Basel) ; 15(5)2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35631381

RESUMEN

The development of oral pediatric forms by pharmaceutical companies is still insufficient. In fact, many drugs used in paediatric oncology, such as temozolomide, are not labeled and adapted for paediatric use. Temozolomide (TMZ) is an alkylating agent used as the standard of care for many adult and pediatric brain tumours, such as neuroblastoma, glioblastoma and medulloblastoma. The present study was carried out to propose a suitable and palatable formulation of the oral liquid preparation of TMZ. The suspension is composed of TMZ suspended in SyrSpend SF pH 4, as well as TMZ crystallization stabilizing agents and sweetening agents. To reach this formulation, several taste-masking agents were evaluated. Here, we describe the method of preparation of the formation as well as the monocentric population treated with the formulation over a 5-year period. A 20 mg/mL TMZ suspension was developed. TMZ suspension is stable for 6 weeks, stored between 2 and 8 degrees, protected from light, and compatible with nasogastric tubes. Thirty-eight patients participated in the palatability study and choose cola flavour, and 104 patients were treated in Gustave Roussy with the developed suspension; no unexpected event was reported. To conclude, we propose here a new TMZ liquid formulation which is stable for at least 6 weeks and well-tolerated with extensive feedback.

4.
Biomaterials ; 27(1): 108-18, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16118015

RESUMEN

Since dextran (DEX) grafted with poly(epsilon-caprolacton) (PCL) side chains (PCL-DEX) copolymers could form nanoparticles with a well defined core-shell structure, we investigated the ability of the DEX coating to modify the interactions with the biological media. We first studied the influence of the DEX coating on the phagocytosis of the nanoparticles by human TPH-1 and J774 murine macrophage-like cell lines. Then, the activation of the complement system (CH50 measurement) at the surface of the particles and the adsorption of plasma proteins (2D-PAGE) were investigated, too. It was found that the modification of the surface with DEX significantly reduced the cytotoxicity towards J774 macrophages: the IC50 was increased from 10 to 600 microg/ml. However, the DEX coating could activate complement, probably due to a loop-like conformation of DEX similar to that of cross-linked DEX in Sephadex (a strong complement activator). In addition, depending on whether the DEX loops were large or compact, preferential adsorption, apolipoproteins or immunoglobulins, was observed.


Asunto(s)
Materiales Biocompatibles Revestidos/química , Nanoestructuras/química , Polisacáridos/farmacología , Adsorción , Animales , Línea Celular , Proliferación Celular , Activación de Complemento , Proteínas del Sistema Complemento , Dextranos/química , Electroforesis en Gel Bidimensional , Humanos , Concentración 50 Inhibidora , Macrófagos/química , Macrófagos/metabolismo , Ratones , Microscopía Confocal , Modelos Químicos , Nanotecnología , Fagocitosis , Poliésteres/química , Polietilenglicoles/química , Polímeros/química , Polisacáridos/química , Factores de Tiempo
5.
J Control Release ; 108(1): 97-111, 2005 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-16169626

RESUMEN

A series of amphiphilic copolymers (PCL-DEX) made of poly(epsilon-caprolactone) (PCL) side chains grafted onto a dextran (DEX) backbone, was used to modify the surface of PCL nanoparticles. PCL-DEX nanoparticles were prepared by a technique derived from emulsion-solvent evaporation. The purpose of the present study was to investigate the DEX coating (quantification, conformation, mobility) in order to better understand particle surface-protein interactions. The DEX coating was deeply examined using different complementary methods: zeta potential measurement, specific degradation of the DEX shell by dextranase, energy-filtering transmission electron microscopy coupled to image-spectrum electron energy-loss spectroscopy, electronic paramagnetic resonance, high performance size exclusion chromatography as well as nonspecific bovine serum albumin adsorption. All our data together supported a core-shell structure of the nanoparticles, DEX moieties constituting the external coating. The amount of DEX located on the nanoparticle surface was estimated to 70%. The organisation of the shell including chains density and mobility was found to be dramatically influenced by DEX molar mass. The steric repulsion conferred by the presence of DEX at the surface of the nanoparticles decreased the adsorption of albumin. The nanoparticle-protein interaction was, however, greatly influenced by the polysaccharide conformation onto the surface.


Asunto(s)
Dextranos/química , Portadores de Fármacos/química , Nanoestructuras/química , Poliésteres/química , Adsorción , Animales , Bovinos , Composición de Medicamentos , Modelos Químicos , Tamaño de la Partícula , Albúmina Sérica Bovina/química , Solubilidad , Propiedades de Superficie
6.
Eur J Pharm Biopharm ; 58(2): 327-41, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15296959

RESUMEN

Surface modified colloidal carriers such as nanoparticles are able to modulate the biodistribution of the loaded drug when given intravenously, but also to control the absorption of drugs administered by other routes. This review presents the different strategies to coat the surface of polymeric as well as inorganic nanoparticles with polysaccharides. Various physicochemical and biological methods have been described to demonstrate such surface modification. The medical applications, mainly in imaging cancer, of polysaccharide-coated nanoparticles are presented, including their abilities to increase the blood circulation time and to target specific tumoral tissues. It has been shown that these coatings allow also to improve drug absorption via nasal or ocular pathways, due the mucoadhesive and/or permeability enhancer properties of the polysaccharides. Finally, the ability of polysaccharide-coated nanoparticles to deliver DNA or oligonucleotides will be discussed.


Asunto(s)
Nanoestructuras , Polisacáridos/química , Animales , Química Farmacéutica , Medios de Contraste , ADN/administración & dosificación , Portadores de Fármacos , Terapia Genética , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia , Oligonucleótidos/administración & dosificación , Tamaño de la Partícula , Preparaciones Farmacéuticas/administración & dosificación , Preparaciones Farmacéuticas/química , Farmacocinética
7.
Pharm Res ; 20(8): 1284-92, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12948027

RESUMEN

PURPOSE: The aim of the present study was to develop a new type of core-shell nanoparticles from a family of novel amphiphilic copolymers, based on dextran (DEX) grafted with poly(epsilon-caprolactone) (PCL) side chains (PCL-DEX). METHODS: A family of PCL-DEX copolymers was synthesized in which both the molecular weight and the proportion by weight of DEX in the copolymer were varied. The nanoparticles were prepared by a technique derived from emulsion-solvent evaporation, during which emulsion stability was investigated using a Turbiscan. The nanoparticle size distribution, density, zeta potential, morphology, and suitability for freeze-drying were determined. RESULTS: Because of their strongly amphiphilic properties, the PCL-DEX copolymers were able to stabilize o/w emulsions without the need of additional surfactants. Nanoparticles with a controlled mean diameter ranging from 100 to 250 nm were successfully prepared. A mechanism of formation of these nanoparticles was proposed. Zeta potential measurements confirmed the presence of a DEX coating. CONCLUSION: A new generation of polysaccharide-decorated nanoparticles has been successfully prepared from a family of PCL-DEX amphiphilic copolymers. They may have potential applications in drug encapsulation and targeting.


Asunto(s)
Poliésteres/química , Polisacáridos/química , Química Farmacéutica , Dextranos/química , Estabilidad de Medicamentos , Emulsiones , Liofilización , Nanotecnología , Tamaño de la Partícula , Solubilidad , Propiedades de Superficie
8.
Int J Pharm ; 254(1): 77-82, 2003 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-12615414

RESUMEN

Oil-in-water nanoemulsions were prepared using a series of synthetic graft copolymers with a backbone of dextran (DEX) and a number of side chains of poly-epsilon-caprolactone (PCL). In this paper, we focus on the o/w emulsion stabilizing abilities of these novel PCL-DEX copolymers, using a recently developed optical analyzer (Turbiscan). The main advantage of Turbiscan is to detect the destabilization phenomena in non-diluted emulsion, much earlier than the naked eye's operator, especially in the case of an opaque and concentrated system. This study shows that PCL-DEX copolymers successfully stabilized ethyl acetate-in-water emulsions, even in the absence of additional surfactants, whereas they were not efficient in stabilizing methylene chloride-in-water emulsions which coalesced fast and irreversibly. The ethyl acetate-in-water emulsion stabilizing ability of PCL-DEX seemed to be related to the localization of their blocks with regard to the oil-water interface.


Asunto(s)
Emulsiones/química , Polímeros/química , Trasplantes , Acetatos/química , Caproatos/química , Fenómenos Químicos , Química Física , Cloruros/química , Dextranos/química , Estabilidad de Medicamentos , Técnicas In Vitro , Lactonas/química , Microesferas , Nefelometría y Turbidimetría/instrumentación , Nefelometría y Turbidimetría/métodos , Aceites , Factores de Tiempo , Agua
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