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1.
Int J Mol Sci ; 25(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38612907

RESUMO

Age-related Macular Degeneration (AMD) is a multifactorial ocular pathology that destroys the photoreceptors of the macula. Two forms are distinguished, dry and wet AMD, with different pathophysiological mechanisms. Although treatments were shown to be effective in wet AMD, they remain a heavy burden for patients and caregivers, resulting in a lack of patient compliance. For dry AMD, no real effective treatment is available in Europe. It is, therefore, essential to look for new approaches. Recently, the use of long-chain and very long-chain polyunsaturated fatty acids was identified as an interesting new therapeutic alternative. Indeed, the levels of these fatty acids, core components of photoreceptors, are significantly decreased in AMD patients. To better understand this pathology and to evaluate the efficacy of various molecules, in vitro and in vivo models reproducing the mechanisms of both types of AMD were developed. This article reviews the anatomy and the physiological aging of the retina and summarizes the clinical aspects, pathophysiological mechanisms of AMD and potential treatment strategies. In vitro and in vivo models of AMD are also presented. Finally, this manuscript focuses on the application of omega-3 fatty acids for the prevention and treatment of both types of AMD.


Assuntos
Ácidos Graxos Ômega-3 , Atrofia Geográfica , Degeneração Macular Exsudativa , Humanos , Ácidos Graxos Insaturados/uso terapêutico , Ácidos Graxos , Ácidos Graxos Ômega-3/uso terapêutico
2.
Pharmaceutics ; 16(3)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38543209

RESUMO

Radiofrequency ablation (RFA) of cancer induces an anti-tumor immunity, which is insufficient to prevent recurrences. In mice, RFA-intratumoral immunotherapy by granulocyte-macrophage colony-stimulating factor (GM-CSF) and Bacillus Calmette-Guerin resulted in complete metastases regression. Infectious risk in human needs replacement of live vaccines. Intratumoral purified protein derivatives (PPD) have never been tested in digestive cancers, and the safety of intratumoral immunotherapy after RFA has not yet been validated in human models. We investigated the therapeutic efficacy of combined radiofrequency ablation (RFA) and intratumoral immunotherapy (ITI) using an immune-muco-adherent thermogel (IMT) in a mouse model of metastatic colorectal cancer (CRC) and the safety of this approach in a pig model. Intratumoral stability of the immunogel was assessed using magnetic resonance imaging (MRI) and bioluminescent imaging. Seventy-four CT26 tumor-bearing female BALB/c mice were treated with RFA either alone or in combination with intratumoral IMT. Regression of distant metastasis and survival were monitored for 60 days. Six pigs that received liver radiofrequency and intralesional IMT injections were followed for 15 days. Experimental gel embolisms were treated using an intravascular approach. Pertinent rheology of IMT was confirmed in tumors, by the signal stability during 3 days in MRI and 7 days in bioluminescence imaging. In mice, the abscopal effect of RFA-intratumoral immunotherapy resulted in regression of distant lesions completed at day 16 vs. a volume of 350 ± 99.3 mm3 in the RFA group at day 25 and a 10-fold survival rate at 60 days. In pigs, injection of immunogel in the liver RFA area was safe after volume adjustment without clinical, hematological, and liver biology disorder. Flow cytometry showed an early increase in CD3 TCRγδ+T cells at D7 (p < 0.05) and a late decrease in CD29+-CD8 T cells at D15 (p < 0.05), reflecting the inflammation status changes. Systemic GM-CSF release was not detectable. Experimental caval and pulmonary thermogel embolisms were treated by percutaneous catheterism and cold serum infusion. RFA-intratumoral immunotherapy as efficient and safe mini-invasive interventional oncology is able to improve ablative treatment of colorectal liver metastases.

3.
J Pharm Biomed Anal ; 227: 115273, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36736111

RESUMO

In this paper, we investigated the retention mechanisms of a reversed-phase/anion-exchange/cation-exchange column (Acclaim trinity P1, Thermo Fisher Scientific) for the separation of epinephrine (EPI) from norepinephrine (NOE). The impact of the acetonitrile (ACN) content, pH, and salt concentration on the retention of these two catecholamines was studied under an isocratic mode with a mobile phase mixture of ACN and ammonium formate or acetate (pH 3 to pH 5). To better understand the retention mechanisms, several retention models were explored, including linear solvent strength, adsorption, quadratic, and mixed-mode models, using various chemical compounds in addition to EPI and NOE. The quadratic and mixed-mode models were the most appropriate to explain the column retention mechanisms according to the Akaike information criterion (AIC). The research showed the importance of the ACN content on the retention of compounds according to the quadratic model, and satisfactory resolution between EPI and NOE (>1.4) was achieved with 50% ACN content. The most important retention parameters were integrated in the mixed-mode model, namely ACN content, pH, and salt concentration. Using a three-factor Box-Behnken design (BBD), other optimal conditions were obtained to separate EPI and NOE with a resolution Rs > 1.5. The ACN content and salt concentrations of the aqueous part of the mobile phase were the parameters with the greatest impact on the separation performance of the stationary phase for both catecholamines. Finally, a rapid and simple separation of a mixture of EPI, NOE, and tetracaine was obtained using a mobile phase composed of ACN/ammonium formate (pH 4; 10 mM) (60:40, v/v), with a satisfactory resolution (>1.5) between the analyte peaks.


Assuntos
Epinefrina , Norepinefrina , Catecolaminas , Cátions , Ânions , Interações Hidrofóbicas e Hidrofílicas , Cromatografia por Troca Iônica
4.
J Sep Sci ; 46(6): e2200766, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36621867

RESUMO

In this study, we discuss the origin of the slightly increased response of the charged aerosol detector when low-concentration polar drugs formulated with sodium chloride are analyzed by hydrophilic interaction liquid chromatography coupled to the charged aerosol detector. In the case of tromethamine mixed with saline solutions, we investigated several levels including the mobile phase, sample matrix, and detection. We show that the analysis of the rich-salted sample results in both interactions with the mobile phase modifiers and the stationary phase during the run time. With 150 mM NaCl as a compounding solution, a slight increase in the tromethamine peak area was observed (<5.5%). Our study suggests that chloride ions in excess sequentially interact firstly with the counterions from the organic modifiers and secondly with the analyte via the stationary phase and the contribution of hydrophilic interaction liquid chromatography retention mechanisms. Because of these effects, the hydrophilic interaction liquid chromatography-charged aerosol detector analysis of drugs in saline solutions requires particular attention, and a correction factor for quantitative purposes that accounts for formulation ions remains appropriate.


Assuntos
Cloretos , Trometamina , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Aerossóis/análise , Interações Hidrofóbicas e Hidrofílicas , Cloreto de Sódio
5.
Pharmaceutics ; 14(10)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36297475

RESUMO

(S)-ketamine presents potential for the management of acute pain and, more specifically, for the prevention of pain associated with care. However, the administration route can be a source of pain and distress. In this context, a smart formulation of (S)-ketamine was designed for buccal administration. The combination of poloxamer 407 and sodium alginate enables increased contact with mucosa components (mucins) to improve the absorption of (S)-ketamine. In this study, rheological studies allowed us to define the concentration of P407 to obtain a gelling temperature around 32 °C. Mucoadhesion tests by the synergism method were carried out to determine the most suitable alginate among three grades and its quantity to optimize its mucoadhesive properties. Protanal LF 10/60 was found to be the most effective in achieving interaction with mucins in simulated saliva fluid. P407 and alginate concentrations were set to 16% and 0.1%. Then, the impact of P407 batches was also studied and significant batch-to-batch variability in rheological properties was observed. However, in vitro drug release studies demonstrated that this variability has no significant impact on the drug release profile. This optimized formulation has fast release, which provides potential clinical interest, particularly in emergencies.

6.
Pharmaceutics ; 14(2)2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-35214185

RESUMO

Glaucoma is a wide-spread eye disease caused by elevated intraocular pressure. Uncontrolled, this pressure may lead to damages to the optic nerve. Prostaglandin analogues, such as latanoprost and travoprost (which are water-insoluble active substances), are the most used class of active pharmaceutical ingredient. To administer them as eye drops, preservatives, such as benzalkonium chloride, are used as solubilizers. The latter is known to cause a local inflammation when used chronically and is not recommended for patients with ocular surface disorders. In this work, we sought to use polysorbate 80 (PS80) as a solubilizing agent simultaneously with sodium hyaluronate (NaHA) as a thickener and cytoprotective agent for the corneal surface. The first part of this study assessed the compatibility of the excipients with the active substance, using physicochemical methods such as spectra fluorescence and differential scanning calorimetry (DSC), as well as the solubilization mechanism of PS80 regarding prostaglandin analogues using nuclear magnetic resonance (NMR). The second part evaluated the stability of a formula candidate, its viscosity upon instillation, and its pharmacokinetic profile in rabbits as compared to the commercially approved medicine Travatan®. The results show that sodium hyaluronate is inert with respect to travoprost, while PS80 successfully solubilizes it, meaning that benzalkonium chloride is no longer required. Moreover, the pharmacokinetic profiles of the rabbits showed that the original formula described in the present study enhanced the ocular bioavailability of the drug, making it a promising product to control intraocular pressure with a potential reduced dosage of travoprost, therefore minimizing its related side effects.

7.
J Oncol Pharm Pract ; 28(6): 1303-1314, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34053358

RESUMO

FOLFOX is the most common chemotherapy combination prescribed in colorectal cancer. It is composed of calcium levofolinate, 5-fluorouracil and oxaliplatin which demonstrated synergistic outcome. Nowadays, the lack of all-in-one formulation is due to the chemical composition of the pharmaceutical products and the highly pH-dependent stability of each drug. Herein, we aimed to investigate the stability of a ternary mixture of 5-fluorouracil, oxaliplatin and calcium levofolinate, knowing that coadministering these drugs would improve their efficacy. The effect of three pHs (5.0, 6.0 and 7.5) and two drug concentrations (8/3/6 and 1/1/1 mg/ml for 5-fluorouracil, oxaliplatin and calcium levofolinate, respectively) were examined. A high-performance liquid chromatography method was developed to separate and quantify the three drugs in one run. At higher concentrations, the ternary mixture was unstable regardless of pH. By reducing concentration, drug stability and compatibility in the mixture was improved at pH 5.0 for up to 3 days at +5°C ± 3 °C. In addition, binary mixtures provided stable properties at defined pHs. 5-fluorouracil/oxaliplatin mixture was stable at pH 5.0 over 48 hours while 5-fluorouracil/calcium levofolinate mixture was stable at pHs 6.0 and 7.5 up to 7 days.


Assuntos
Neoplasias Colorretais , Fluoruracila , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cálcio , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/uso terapêutico , Humanos , Leucovorina/uso terapêutico , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina/uso terapêutico
8.
Talanta ; 238(Pt 2): 123050, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34801907

RESUMO

Tromethamine (TMM), often encountered in a final drug product, exhibits interesting chemical properties as a counter ion, buffer, or active ingredient. European and US pharmacopeias propose titration against hydrogen chloride for TMM assays. However, this method can be a hindrance when using drugs containing low concentrations of TMM in complex buffered formulations. Due to the lack of chromophores and the high hydrophilicity of TMM, we performed a simple and reliable hydrophilic interaction chromatography coupled with a charged aerosol detector (HILIC-CAD) separation approach as an alternative for TMM analysis. An amide stationary phase and a mobile phase consisting of a binary mixture of acetonitrile and 10 mM ammonium formate, pH 3 (80/20, V/V) were used. As the CAD response deeply depends on parameters such as stationary phases and pH buffer, we investigated their impact and explored the optimal signal conditions. Including TMM analogs such as tris(hydroxymethyl) nitromethane and 2-amino-2-ethyl-1,3-propanediol allowed us to select these parameters appropriately. The effects of the evaporation temperature, flow rate, and power function value (PFV) on the CAD signal response were also studied and optimized. The method was validated according to the ICH Q2 R1 guidelines. A linear response (mean R2 > 0.997) covering the range for low TMM concentrations (170-520 µg/mL) was achieved. Satisfactory intra-day and inter-day precisions were obtained with RSDs lower than 1.9% and 2.8%, respectively. The trueness ranged from 99.6% to 101.2%, and the LOD was found to be 1.1 µg/mL. The HILIC-CAD method has been applied to a sterile TMM solution for injection.


Assuntos
Trometamina , Aerossóis , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Interações Hidrofóbicas e Hidrofílicas
9.
Hosp Pharm ; 56(4): 332-337, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34381270

RESUMO

Purpose: Pentobarbital is a sedative agent to limit children motion during computed tomography or magnetic resonance imaging (MRI) and ensures the successful completion of the imaging procedure. However, data on rectal drug formulation and its stability in practice are not available. The aim of this study was to formulate and evaluate the stability of a ready-to-use rectal pentobarbital gel. Methods: The formulation consisted of a hydrated gel containing 25 mg/mL of pentobarbital sodium, packaged in 10-mL amber glass bottles and stored at either 22°C to 25°C or 2°C to 8°C. At each predetermined time point, samples were taken for visual inspection, pH measurement, and analysis by a validated stability-indicating high-performance liquid chromatography (HPLC) method. The viscosity parameters of the hydrogel formulation were assessed. Results: The freshly prepared rectal formulations appeared clear, colorless, and particular-free with pH readings of 9.75 to 9.83. Over the 90 days of the study period, there was no significant change in appearance or pH values for all stability samples. The HPLC results confirmed the chemical stability when stored at 2°C to 8°C or at 22°C to 25°C. Conclusion: Pentobarbital hydrogel 25 mg/mL are stable chemically at least 90 days and can be administered to children for an effective and fast sedation.

10.
Eur J Pharm Biopharm ; 169: 37-43, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33727143

RESUMO

One of the main problems of colorectal cancer is not the treatment of the primary tumor but the metastatic stage. Means of metastatic spread is the invasion of the peritoneal cavity which leads to peritoneal metastasis (PM). PM cannot be easily cured, and the current treatments is rather heavy, combining cytoreductive surgery with intravenous and intraperitoneal chemotherapy. This therapeutic procedure is associated with significant morbidity, altered patient quality of life and poor prognosis. We postulated that development of a prophylactic treatment could be of high interest in this context. In this study, we formulated an anti-adhesive thermogel which contains chemotherapeutics to play a role of a barrier against tumor cells implantation, avoiding their adhesion and treating the remaining tumor cells with chemotherapy intraperitoneally in a mice model of PM. The bioavailability of the thermogel was tested intraperitoneally in mice. No sign of toxicity was observed in terms of change in body weight, anatomopathology and blood biomarkers. In vitro experiments proved that the thermogel induced limited adhesion of the tumor cells. Loading of oxaliplatin (Ox) and 5-Fluorouracil (5-FU) into the thermogel were able to significantly decreased peritoneal carcinomatosis index (PCI) (-58%) and ascites (-70%) in a murine model of peritoneal metastases. These pre-clinical results confirmed that smart thermogel associated with standard chemotherapy 5-FU and Ox could be a good candidate to decrease the risk of tumor cell implantation during cytoreductive surgery and prevent future metastatic process.


Assuntos
Neoplasias Colorretais , Procedimentos Cirúrgicos de Citorredução/métodos , Fluoruracila/administração & dosagem , Quimioterapia Intraperitoneal Hipertérmica/métodos , Oxaliplatina/administração & dosagem , Neoplasias Peritoneais , Poloxâmero/farmacologia , Animais , Antineoplásicos/administração & dosagem , Disponibilidade Biológica , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Terapia Combinada , Modelos Animais de Doenças , Géis , Camundongos , Estadiamento de Neoplasias , Neoplasias Peritoneais/etiologia , Neoplasias Peritoneais/terapia , Tensoativos/farmacologia , Resultado do Tratamento
11.
Pharmaceutics ; 13(1)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477667

RESUMO

Oral lichen planus (OLP) is an ongoing and chronic inflammatory disease affecting the mucous membrane of the oral cavity. Currently, the treatment of choice consists in the direct application into the buccal cavity of semisolid formulations containing a corticosteroid molecule to decrease inflammatory signs and symptoms. However, this administration route has shown various disadvantages limiting its clinical use and efficacy. Indeed, the frequency of application and the incorrect use of the preparation may lead to a poor efficacy and limit the treatment compliance. Furthermore, the saliva clearance and the mechanical stress present in the buccal cavity also involve a decrease in the mucosal exposure to the drug. In this context, the design of a new pharmaceutical formulation, containing a steroidal anti-inflammatory, mucoadhesive, sprayable and exhibiting a sustained and controlled release seems to be suitable to overcome the main limitations of the existing pharmaceutical dosage forms. The present work reports the formulation, optimization and evaluation of the mucoadhesive and release properties of a poloxamer 407 thermosensitive hydrogel containing a poorly water-soluble corticosteroid, dexamethasone acetate (DMA), threaded into hydroxypropyl-beta-cyclodextrin (HP-ß-CD) molecules. Firstly, physicochemical properties were assessed to ensure suitable complexation of DMA into HP-ß-CD cavities. Then, rheological properties, in the presence and absence of various mucoadhesive agents, were determined and optimized. The hydration ratio (0.218-0.191), the poloxamer 407 (15-17 wt%) percentage and liquid-cyclodextrin state were optimized as a function of the gelation transition temperature, viscoelastic behavior and dynamic flow viscosity. Deformation and resistance properties were evaluated in the presence of various mucoadhesive compounds, being the sodium alginate and xanthan gum the most suitable to improve adhesion and mucoadhesion properties. Xanthan gum was shown as the best agent prolonging the hydrogel retention time up to 45 min. Furthermore, xanthan gum has been found as a relevant polymer matrix controlling drug release by diffusion and swelling processes in order to achieve therapeutic concentration for prolonged periods of time.

12.
Int J Pharm ; 592: 120041, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33157213

RESUMO

Peritoneum represents a frequent site of metastasis especially for digestive and ovarian primary cancers. The conventional approach to treat peritoneal metastasis consists in systemic chemotherapy, but the median survival associated is only a few months. Recent therapeutic developments result in an aggressive strategy associating cytoreductive surgery (CRS) and hyperthermic intra peritoneal chemotherapy (HIPEC). However, a recent study failed to show an improvement in the overall survival and relapse free survival of this combo in comparison to CRS alone. Confronted to a lack of guidelines, several drug delivery systems (DDS) had been developed and tested in animal models to offer an effective easy-to-use solution for surgeons to prevent peritoneal metastasis. In this work, we reviewed most of the strategies used to treat peritoneal metastasis (PM) from digestive or ovarian origin and concentrated on 3 different DDS strategies: particulates DDS, non particulates DDS (including implants, films and gels) and combination of both (in particular hydrogels loaded with particles).


Assuntos
Hipertermia Induzida , Neoplasias Ovarianas , Neoplasias Peritoneais , Terapia Combinada , Procedimentos Cirúrgicos de Citorredução , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/prevenção & controle , Peritônio
13.
Eur J Pharm Biopharm ; 157: 154-164, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33222768

RESUMO

Spurred by high risk for local tumor recurrence and non-specific toxicity of systemic chemotherapy, clinicians have recently granted a growing interest to locoregional therapeutic strategies. In this perspective, we recently developed a multipurpose thermosensitive hydrogel based on reversible thermogelling properties of poloxamers P407 and P188, a bioadhesive excipient and antineoplastic effect of 5-fluorouracil (5-FU) for the local treatment of colorectal cancer (CRC) in ectopic CT26 murine models. Antitumor efficacy was assessed in mice following intratumoral (IT) injection mimicking neoadjuvant therapy and subcutaneous (SC) application after tumor excision simulating adjuvant therapy. Rheological characterization disclosed that P407/P188/alginate 20/2/1% w/v thermosensitive hydrogel is an injectable free-flowing solution at ambient temperature that undergoes a SOL-GEL transition at 26.0 °C ± 0.6 °C and thereby forms in situ a non-flowing gel at physiological temperature. The generated gel presented an elastic behavior and responded according to a shear-thinning fluid upon shear rate. Although delayed by the addition of alginate 1% w/v, 5-FU is released mainly by diffusion mechanism. The local delivery of 5-FU from P407/P188/alginate/5-FU 20/2/1/0.5% w/v hydrogel in the preclinical tumor models led to a significant tumor growth delay. These results demonstrated that poloxamer-based thermosensitive hydrogels provide a simple and efficient means for local chemotherapeutics delivery.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Portadores de Fármacos , Fluoruracila/administração & dosagem , Terapia Neoadjuvante , Poloxâmero/química , Polímeros Responsivos a Estímulos/química , Temperatura , Alginatos/química , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Quimioterapia Adjuvante , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Liberação Controlada de Fármacos , Feminino , Fluoruracila/química , Fluoruracila/metabolismo , Hidrogéis , Camundongos Endogâmicos BALB C , Solubilidade , Carga Tumoral/efeitos dos fármacos
14.
Pharmaceutics ; 12(8)2020 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-32784378

RESUMO

Presenting many advantages, solid oral dosage forms (SODFs) are widely manufactured and frequently prescribed in older populations regardless of the specific characteristics of patients. Commonly, patients with dysphagia (swallowing disorders) experience difficulties taking SODFs, which may lead to non-adherence or misuse. SODF characteristics (e.g., size, shape, thickness) are likely to influence swallowability. Herein, we used the acceptability reference framework (the ClinSearch acceptability score test (CAST))-a 3D-map juxtaposing two acceptability profiles-to investigate the impact of tablet size on acceptability. We collected 938 observer reports on the tablet intake by patients ≥65 years in hospitals or care homes. As we might expect, tablets could be classified as accepted in older patients without dysphagia (n = 790), while not in those with swallowing disorders (n = 146). However, reducing the tablet size had a significant impact on acceptability in this subpopulation: tablets <6.5 mm appeared to be accepted by patients with swallowing disorders. Among the 309 distinct tablets assessed in this study, ranging in size from 4.7 to 21.5 mm, 83% are ≥6.5 mm and consequently may be poorly accepted by institutionalized older people and older inpatients suffering from dysphagia. This underlines the need to develop and prescribe medicines with the best adapted characteristics to reach an optimal acceptability in targeted users.

15.
Pharmaceutics ; 12(4)2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32326492

RESUMO

Mydriasis is required prior to many eye examinations and ophthalmic surgeries. Nowadays, phenylephrine hydrochloride (PHE) and tropicamide (TPC) are extensively used to induce mydriasis. Several pharmaceutic dosage forms of these two active ingredients have been described. However, no optimal therapeutic strategy has reached the market. The present work focuses on the formulation and evaluation of a mucoadhesive ion-activated in situ gelling delivery system based on gellan gum and hydroxyethylcellulose (HEC) for the delivery of phenylephrine and tropicamide. First, in vitro drug release was studied to assess appropriate sustained drug delivery on the ocular surface region. Drug release mechanisms were explored and explained using mathematical modeling. Then, in situ gelling delivery systems were visualized using scanning electron microscopy illustrating the drug release phenomena involved. Afterward, cytotoxicity of the developed formulations was studied and compared with those of commercially available eye drops. Human epithelial corneal cells were used. Finally, mydriasis intensity and kinetic was investigated in vivo. Mydriasis pharmacodynamics was studied by non-invasive optical imaging on vigilant rabbits, allowing eye blinking and nasolacrimal drainage to occur physiologically. In situ gelling delivery systems mydriasis profiles exhibited a significant increase of intensity and duration compared with those of conventional eye drops. Efficient mydriasis was achieved following the administration of a single drop of in situ gel reducing the required amount of administered active ingredients by four- to eight-fold compared with classic eye drop regimen.

16.
Int J Pharm ; 574: 118734, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31705970

RESUMO

Achieving drug delivery at the ocular level encounters many challenges and obstacles. In situ gelling delivery systems are now widely used for topical ocular administration and recognized as a promising strategy to improve the treatment of a wide range of ocular diseases. The present work describes the formulation and evaluation of a mucoadhesive and ion-activated in situ gelling delivery system based on gellan gum and hydroxyethylcellulose for the delivery of phenylephrine and tropicamide. First, physico-chemical characteristics were assessed to ensure suitable properties regarding ocular administration. Then, rheological properties such as viscosity and gelation capacity were determined. Gelation capacity of the formulations and the effect of hydroxyethylcellulose on viscosity were demonstrated. A new rheological method was developed to assess the gel resistance under simulated eye blinking. Afterward, mucoadhesion was evaluated using tensile strength test and rheological synergism method in both rotational and oscillatory mode allowing mucoadhesive properties of hydroxyethylcellulose to be point out. Finally, residence time on the ocular surface was investigated in vivo, using cyanine 5.5 dye as a fluorescent marker entrapped in the in situ gelling delivery systems. Residence performance was studied by non-invasive optical imaging on vigilant rabbits, allowing eye blinking and nasolacrimal drainage to occur physiologically. Fluorescence intensity profiles pointed out a prolonged residence time on the ocular surface region for the developed formulations compared to conventional eye drops, suggesting in vitro / in vivo correlations between rheological properties and in vivo residence performances.


Assuntos
Celulose/análogos & derivados , Córnea/efeitos dos fármacos , Géis/química , Géis/farmacologia , Soluções Oftálmicas/química , Soluções Oftálmicas/farmacologia , Polissacarídeos Bacterianos/química , Administração Oftálmica , Animais , Disponibilidade Biológica , Celulose/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Excipientes/química , Masculino , Coelhos , Reologia/métodos , Viscosidade
17.
BMC Geriatr ; 19(1): 344, 2019 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-31810442

RESUMO

BACKGROUND: In institutional care, oral liquid pharmaceutical products are widely prescribed for older patients, especially for those with swallowing disorders. As medicines acceptability is a key factor for compliance in the older population, this study investigated the acceptability of oral liquid pharmaceutical products in this targeted population. METHODS: An observational, multicenter, prospective study was conducted in eight geriatric hospitals and eight nursing homes in France. Observers reported several behaviours/events describing the many aspects of acceptability for various pharmaceutical products' uses in patients aged 65 and older. Acceptability scores of oral liquid pharmaceutical products were obtained using an acceptability reference framework (CAST - ClinSearch Acceptability Score Test®): a 3D-map summarizing the different users' behaviors, with two clusters defining the positively and negatively accepted profiles materialized by the green and red zones, respectively. RESULTS: Among 1288 patients included in the core study and supporting the acceptability reference framework, 340 assessments were related to the administration of an oral liquid pharmaceutical product. The mean age of these patients was 87 (Range [66-104y]; SD = 6.7), 68% were women and 16% had swallowing disorders. Globally, the oral liquid pharmaceutical products were classified as "positively accepted," the barycenter of the 340 assessments, along with the entire confidence ellipses surrounding it, were positioned on the green zone of the map. Sub-populations presenting a different acceptability profile have also been identified. For patients with swallowing disorders, the oral liquid pharmaceutical products were classified as "negatively accepted," the barycenter of the 53 assessments along with 87% of its confidence ellipses were associated with this profile. A gender difference was observed for unflavored oral liquids. In women, they were classified "negatively accepted," the barycenter of the 68 assessments with 75% of its confidence ellipses were located in the red zone, while they were classified "positively accepted" in men. CONCLUSION: This study showed that oral liquid pharmaceutical products are a suboptimal alternative to solid oral dosage forms in patients with swallowing disorders. To ensure an optimal acceptability, prescribers should also consider the presence of a taste-masker in these oral liquids. As highlighted herein, palatability remains crucial in older populations, especially for women.


Assuntos
Transtornos de Deglutição/fisiopatologia , Deglutição/fisiologia , Cooperação do Paciente , Preparações Farmacêuticas/administração & dosagem , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Casas de Saúde , Estudos Prospectivos , Fatores Sexuais , Paladar
18.
PLoS One ; 14(8): e0221261, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31430323

RESUMO

INTRODUCTION: Medicine acceptability is a multi-faceted concept driven by both product and user characteristics. Although a key factor for treatment effectiveness, especially in vulnerable populations, knowledge of those medicine features that best promote individual user acceptability remains fragmented. Focusing on paracetamol, this study has explored the appropriateness of pharmaceutical products in different dosage forms to achieve adequate patient acceptability from infants to centenarians. METHODS: This observational, multicentre, prospective study was carried out in 10 hospitals, 8 nursing homes and over 150 community dispensaries. Observers reported several behaviours/events evaluating acceptability for 1016 different pharmaceutical product uses in paediatrics (<18y.) and 1288 in the elderly (≥65y.). Using mapping and clustering, a multivariate approach offered an intelligible reference framework for each population, providing comprehensive scores: positively or negatively accepted. RESULTS: Among all the evaluations supporting the acceptability reference frameworks, there were 502 reports on paracetamol products intake. Herein we focused on the 5 products with ≥30 evaluations. Although oral suspension and powder for oral solution were positively-accepted in the paediatric group, the powder had a higher rate of negative patient reaction (p<0.001). Of those that received this formulation, 72% were ≤8y., and therefore suitable to receive the better accepted oral suspension. In the elderly, patients with swallowing disorders were preferentially treated with such powders (p<0.001), which were less often fully taken than orally disintegrating tablets (p<0.001). Even in those patients ≥90y., capsule formulations appeared to be the best accepted product in patients without swallowing alterations, and thus could be a suitable alternative to the powder in this population. CONCLUSIONS: By better integrating patient characteristics when choosing dosage forms, clinicians and caregivers may improve treatment acceptability and adherence. Moreover, hospitals and healthcare institutions could optimise purchasing to best suit their local population, disseminating information to help staff align specific dosage forms to targeted patients.


Assuntos
Acetaminofen/administração & dosagem , Formas de Dosagem , Adesão à Medicação , Populações Vulneráveis , Administração Oral , Adolescente , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Estudos Prospectivos
19.
Pharmaceutics ; 11(8)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374869

RESUMO

Palatability is a recognized driver of medicine acceptability in pediatrics but deemed less relevant in older populations due to sensory decline. Preliminary findings from an observational study implicated palatability problems with one Alzheimer's medicine. Among 1517 observer reports combining multiple measures on medicines uses in patients aged over 64, we focused on two original formulations of memantine (Ebixa®, tablets (n = 25) and oral solution (n = 60)). Evaluations were scored with an acceptability reference framework (CAST), the rodent Brief Access Taste Aversion (BATA) model tested aversiveness. Focusing on women treated with Ebixa® (n = 54), the oral formulation sub-group was classified as "negatively accepted", while the coated tablet was associated with the "positively accepted" cluster. In men, both formulations belonged to the "positively accepted" profile. Using BATA, the original oral solution was categorized as highly aversive/untolerated while solutions of excipients only were well tolerated. Furthermore, the number of licks was significantly lower in female than in male rats. These results revealed that medicine palatability remains important for acceptability in older populations. Moreover, converging results from humans and animal models highlighted that palatability profiles can significantly vary between the sexes. These drivers should be closely considered during drug development to enhance acceptability in this population.

20.
Int J Pharm ; 567: 118421, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31176849

RESUMO

Intratumoral injection of biocompatible gels is increasingly used for the sustained delivery of drugs and vaccines to enhance the anti-cancer immune response. Granulocyte-macrophage colony stimulating factor (GM-CSF) has become an attractive adjuvant thanks to its ability to boost the antitumor immune response by inducing proliferation, maturation and migration of the dendritic-cells (DCs) and the differentiation of lymphocytes. Killed Mycobacteria, such as Heat-killed Mycobacterium tuberculosis (HKMT) have been used in several studies as TLR-2 agonist to increase maturation of DCs. In this study, we designed a mucoadhesive thermosensitive formulation for the local delivery of GM-CSF and HKMT in order to enhance DCs activation and improve the local antitumor immune response. This formulation was selected based on its elastic and mucoadhesive properties obtained thanks to rheological studies. More importantly, intratumoral residence time of the labelled gel and protein were evidenced by means of MRI and non invasive in vivo optical imaging. Then, the efficacy of the combination of immunomodulators loaded thermogel was demonstated in vitro and in vivo. The selected thermogel exhibits rheological properties which confer a good elasticity and increased residence time of the immunostimulatory agents in the tumor, thus increasing the recruitment of DCs and T cytotoxic CD8+ lymphocytes.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Hidrogéis/administração & dosagem , Fatores Imunológicos/administração & dosagem , Mycobacterium tuberculosis , Neoplasias/tratamento farmacológico , Adesividade , Animais , Medula Óssea/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Células Dendríticas/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/química , Hidrogéis/química , Fatores Imunológicos/química , Camundongos , Camundongos Endogâmicos BALB C , Mucinas/química , Células NIH 3T3 , Neoplasias/imunologia , Neoplasias/patologia , Imagem Óptica , Poloxâmero/administração & dosagem , Poloxâmero/química , Reologia
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