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1.
Antioxidants (Basel) ; 12(2)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36829983

RESUMO

In vitro studies have shown that epigallocatechin gallate (EGCG), the most potent antioxidant of the green tea polyphenol catechins, is able to effectively prevent the formation of amyloid plaques and induce their clearance. However, its high chemical reactivity promotes high chemical instability, which represents a major obstacle for the development of pharmaceutical forms containing solubilized EGCG, an essential condition for a better systemic passage via the oral route. After discovering that EGCG forms a deep eutectic with choline chloride, we exploited this property to formulate and patent liquid-filled capsules containing 200-800 mg of soluble EGCG in easy-to-administer sizes. The gelatin envelopes used are of the conventional type and their filling has been achieved using 3D printing technology. Not only did the EGCG-choline complex allow the formulation of hydrophilic solutions with a high concentration of active substance but it also contributed significantly to its chemical stability, since after at least 18 months of storage at 25 °C/60% RH and one year at 40 °C/75% RH, the capsules show unchanged hardness, chromatographic profiles and antioxidant activity compared to T0. Preclinical studies in monkeys showed that bioavailability was increased by a factor of 10 compared to marketed capsules comprising EGCG powder. This pharmaceutical development was conducted in the context of upcoming clinical trials to evaluate EGCG alone or in combination when treating transthyretin and light-chain cardiac amyloidosis.

2.
Pharmaceuticals (Basel) ; 14(12)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34959643

RESUMO

Because of its antioxidant, antimutagenic, and anti-infectious properties, epigallocatechin gallate (EGCG) is the most interesting compound among the green tea catechins polyphenols. However, its health effects are inconclusive due to its very low bioavailability, largely due to a particular instability that does not allow EGCG to reach the potency required for clinical developments. Over the last decade, many efforts have been made to improve the stability and bioavailability of EGCG using complex delivery systems such as nanotechnology, but these efforts have not been successful and easy to translate to industrial use. To meet the needs of a large-scale clinical trial requiring EGCG in a concentrated solution to anticipate swallowing impairments, we developed an EGCG-based aqueous solution in the simplest way while trying to circumvent EGCG instability. The solution was thoroughly characterized to sort out the unexpected stability outcome by combining experimental (HPLC-UV-mass spectrometry and infrared spectroscopy) and computational (density functional theory) studies. Against all odds, the EGCG-sucrose complex under certain conditions may have prevented EGCG from degradation in aqueous media. Indeed, in agreement with the ICH guidelines, the formulated solution was shown to be stable up to at least 24 months under 2-8 °C and at ambient temperature. Furthermore, considerable improvement in bioavailability in rats, against EGCG powder formulated in hard-gel capsules, was shown after gavage. Thus, the proposed formulation may provide an easily implementable platform to administer EGCG in the context of clinical development.

3.
J Pharm Biomed Anal ; 197: 113983, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33640689

RESUMO

Ruxolitinib is a Janus Kinase inhibitor currently approved for the treatment of myelofibrosis. It is also a promising drug for the treatment of skin and infectious diseases. In terms of pharmaceutical stability, although ruxolitinib has been established as being sensitive to light, no data on photodegradation processes are available to date, while these may be useful for quality risk management and any potential development of other pharmaceutical forms for other routes of administration. One way to partially fill this gap was to carry out a study that combines a consistent determination of the most sensitive sites of the molecule to photolysis through theoretical calculations based on functional density, with the identification of the main photodegradation products obtained after forced degradation. This integrated approach has shown converging results describing the mechanisms based on photo-oxidation that can lead to the opening of the pyrrole ring. Having access to the structure of the degradation products and intermediates then made it possible to carry out an in silico evaluation of their potential mutagenicity and it appears that some of them feature alert structures.


Assuntos
Preparações Farmacêuticas , Pirazóis , Nitrilas , Fotólise , Inibidores de Proteínas Quinases , Pirimidinas
4.
J Pharm Biomed Anal ; 196: 113934, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33549876

RESUMO

Umifenovir is an antiviral drug approved in China and Russia for the treatment of influenza. The available dosage form consists of capsules marketed under the brand name Arbidol®. Due to its broad spectrum, umifenovir may also be used in other viral contexts, alone or combined with other antiviral drugs. Although knowledge of umifenovir intrinsic stability may be useful for any potential development of other pharmaceutical forms for other routes of administration and for quality risk management, no data regarding this matter is available to date. In this study, the exploration of the molecule's behaviour under hydrolytic, oxidative and photolytic conditions was carried out experimentally and supported by density functional theory (DFT) studies. It comes out that umifenovir is sensitive to these stress conditions giving rise to 6 structurally characterized degradation products. The one-electron oxidation process produced on the sulphur atom is probably the main cause of umifenovir degradation with reference to the structures of the degradation products formed and the DFT data.


Assuntos
Antivirais , Influenza Humana , Antivirais/uso terapêutico , China , Estabilidade de Medicamentos , Humanos , Hidrólise , Indóis , Influenza Humana/tratamento farmacológico , Oxirredução , Fotólise , Federação Russa
5.
Eur J Hosp Pharm ; 27(e1): e48-e52, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32296505

RESUMO

Objectives: In recent years, various formulations containing rapamycin, mainly petrolatum-based, have been tested on facial angiofibromas in tuberous sclerosis. They are often poorly tolerated due to irritation and bleeding. In addition, their effectiveness was insufficient in young adults. The objective of this study was to develop and characterise a hydro-alcoholic gel containing solubilised rapamycin. The stability of the product stored at 4°C was evaluated over 1 year. Methods: Two different 0.1% rapamycin gels were formulated with or without α-tocopherol and urea. Different methods were used to characterise the gels: HPLC, gas chromatography, pH, visual observation and optical microscopy. A physico-chemical and microbiological stability study was also conducted for 1 year at 4°C. Results: Gels were physically and microbiologically stable after 1 year at 4°C: organoleptic characteristics and pH unchanged, no significant decrease in rapamycin was observed, tocopherol droplet size was constant and rheological behaviour was not altered. Conclusions: This study describes a new gel formulation to improve skin penetration using various excipients to promote skin tolerance. This study provides, for the first time, detailed stability data for a hydro-alcoholic rapamycin gel.


Assuntos
Angiofibroma/tratamento farmacológico , Antibióticos Antineoplásicos/química , Composição de Medicamentos/tendências , Neoplasias Faciais/tratamento farmacológico , Sirolimo/química , Administração Tópica , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/tendências , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Géis , Humanos , Interações Hidrofóbicas e Hidrofílicas , Sirolimo/administração & dosagem , Sirolimo/análise , Resultado do Tratamento
6.
BMJ Open ; 8(8): e021943, 2018 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-30099397

RESUMO

INTRODUCTION: The management of acute upper gastrointestinal bleeding (UGIB) is challenging in patients with cirrhosis, as it is responsible for severe complications and high mortality rates. Tranexamic acid (TXA) may help control the bleeding by counterbalancing cirrhosis-related hyperfibrinolysis. Still, there is a lack of unbiased data to conclude on its efficacy. The aim of this study is to evaluate the efficacy of TXA in the early treatment of acute UGIB in patients with cirrhosis. METHODS AND ANALYSIS: This study is a multicentre, randomised, double-blind, placebo-controlled trial, for adult patients with cirrhosis presenting with an acute UGIB and allocated to one of two arms: TXA or placebo (saline). Physicians from emergency mobile services, emergency departments (EDs) or intensive care units (ICUs) can include patients. Besides study intervention, standard care for UGIB will be performed as recommended. Intervention will consist an intravenous infusion of 10 mL of TXA (1 g) or saline, immediately followed by three identical intravenous infusions over 8 hours each (total dose of 4 g of TXA or 40 mL of placebo over 24 hours). Main analyses will be conducted in intention to treat on every patient included, then in modified intention to treat on patients with underlying lesion of portal hypertension visualised by endoscopy. The main objective is to show efficacy of TXA until day 5 on a composite criterion (bleeding control, rebleeding episodes and mortality). Secondary objectives aim at showing the efficacy of TXA on each individual component of the main outcome measure and others at 6 weeks and later (transjugular intrahepatic portosystemic shunt procedure, cirrhosis-specific complications, length of stay in ICU and in hospital, safety and tolerance of TXA, liver transplantation). Included patients will be followed up to 1 year after inclusion.500 patients will be necessary to show a reduction in the prevalence of the primary outcome from 30% to 18% with a bilateral alpha risk of 5% and a power of 80%. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Comité de Protection des Personnes Ile-de-France 1 (CPP-IDF1). Results will be disseminated via publications in peer-review medical journals and scientific forums. PROTOCOL VERSION: This protocol is based on the latest version, as established on 11 October 2017 and validated by the IRB CPP Ile-de-France 1. TRIAL REGISTRATION NUMBER: NCT03023189.


Assuntos
Antifibrinolíticos/administração & dosagem , Hemorragia Gastrointestinal/tratamento farmacológico , Cirrose Hepática/complicações , Ácido Tranexâmico/administração & dosagem , Administração Intravenosa , Adulto , Antifibrinolíticos/efeitos adversos , Método Duplo-Cego , França , Hemorragia Gastrointestinal/etiologia , Humanos , Estudos Multicêntricos como Assunto , Ensaios Clínicos Pragmáticos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Ácido Tranexâmico/efeitos adversos , Resultado do Tratamento
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