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1.
Nanomedicine (Lond) ; 19(4): 293-301, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38270378

RESUMO

Background: Leishmaniasis, caused by the protozoan Leishmania sp., infects phagocyte cells present in lymphatic organs. This study demonstrates the influence of nanostructured lipid carrier-loaded hydroxymethylnitrofurazone (NLC-NFOH) on lymphatic uptake using a chylomicron-blocking flow model in rats. Method: Lymphatic uptake of NFOH was assessed 1 h after oral administration of dimethyl sulfoxide with NFOH or NLC-NFOH with and without cycloheximide pretreatment. Result: Dimethyl sulfoxide with NFOH and NLC-NFOH showed NFOH serum concentrations of 0.0316 and 0.0291 µg/ml, respectively. After chylomicron blocking, NFOH was not detected. Conclusion: Despite log P below 5, NFOH was successfully taken up by the lymphatic system. Long-chain fatty acids and particle size might be main factors in these findings. NLC-NFOH is a promising and convenient platform for treating leishmaniasis via oral administration.


Assuntos
Leishmaniose , Nanoestruturas , Nitrofurazona/análogos & derivados , Ratos , Animais , Dimetil Sulfóxido , Quilomícrons , Administração Oral , Portadores de Fármacos , Tamanho da Partícula
2.
Pharmaceutics ; 15(11)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-38004512

RESUMO

The lymphatic system plays a crucial role in the absorption of lipophilic drugs, making it an important route for drug delivery. In this study, an in vitro model using Intralipid® was developed to investigate the lymphatic uptake of drugs. The model was validated using cannabidiol, halofantrine, quercetin, and rifampicin. Remarkably, the uptake of these drugs closely mirrored what would transpire in vivo. Furthermore, adding peanut oil to the model system significantly increased the lymphatic uptake of rifampicin, consistent with meals containing fat stimulating lymphatic drug uptake. Conversely, the inclusion of pluronic L-81 was observed to inhibit the lymphatic uptake of rifampicin in the model. This in vitro model emerges as a valuable tool for investigating and predicting drug uptake via the lymphatic system. It marks the first phase in developing a physiologically based predictive tool that can be refined further to enhance the precision of drug interaction predictions with chylomicrons and their subsequent transport via the lymphatic system. Moreover, it can be employed to explore innovative drug formulations and excipients that either enhance or hinder lymphatic drug uptake. The insights gained from this study have significant implications for advancing drug delivery through the lymphatic system.

3.
Int J Pharm ; 644: 123324, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37591475

RESUMO

Lung cancer is the leading cause of cancer-related death. In addition to new innovative approaches, practical strategies that improve the efficacy of already available drugs are urgently needed. In this study, an inhalable dry powder formulation is used to repurpose flubendazole, a poorly soluble anthelmintic drug with potential against a variety of cancer lineages. Flubendazole nanocrystals were obtained through nanoprecipitation, and dry powder was produced by spray drying. Through fractional factorial design, the spray drying parameters were optimized and the impact of formulation on aerolization properties was clarified. The loading limitations were clarified through response surface methodology, and a 15% flubendazole loading was feasible through the addition of 20% L-leucine, leading to a flubendazole particle size of 388.6 nm, median mass aerodynamic diameter of 2.9 µm, 50.3% FPF, emitted dose of 83.2% and triple the initial solubility. Although the cytotoxicity of this formulation in A549 cells was limited, the formulation showed a synergistic effect when associated with paclitaxel, leading to a surprising 1000-fold reduction in the IC50. Compared to 3 cycles of paclitaxel alone, a 3-cycle model combined treatment increased the threshold of cytotoxicity by 25% for the same dose. Our study suggests, for the first time, that orally inhaled flubendazole nanocrystals show high potential as adjuvants to increase cytotoxic agents' potency and reduce adverse effects.


Assuntos
Adjuvantes Imunológicos , Nanopartículas , Pós , Adjuvantes Farmacêuticos , Paclitaxel/farmacologia
4.
Int J Pharm ; 630: 122428, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36436741

RESUMO

Dapsone (DAP)is a dual-function drug substance; however, its limited water solubility may impair its bioavailability. Drug nanocrystals are an alternative to overcome this limitation. Herein, a DAP nanosuspension was prepared using adesign space approach aiming to investigate the influence of raw material properties and process parameters on the critical quality attributes of the drugnanocrystals. Optimized nanocrystals with 206.3 ± 6.7 nm using povacoat™ as stabilizer were made. The nanoparticles were characterized by dynamic light scattering, laser diffraction, scanning electron microscopy, differential scanning calorimetry, X-ray powder diffraction, and saturation solubility. Compared to the raw material, the nanocrystals were 250-times smaller. Meanwhile, its crystalline state remained basically unchanged even after milling and drying. The nanosuspension successfully maintained its physical stability inlong-termandaccelerated stability studiesover, 4 and 3 months. Furthermore, toxicity studiesshowed low a toxicity at a20 mg/kg. As expected for nanocrystals, the size reduction improvedsaturation solubility3.78 times in water. An attempt to scale up from lab to pilot scale resulted nanocrystals of potential commercial quality. In conclusion, the present study describes the development of dapsone nanocrystals for treating infectious and inflammatory diseases. The nanocrystal formuation can be scaled up for commercial use.


Assuntos
Nanopartículas , Água , Tamanho da Partícula , Água/química , Dapsona , Solubilidade , Disponibilidade Biológica , Nanopartículas/química , Difração de Raios X , Varredura Diferencial de Calorimetria
5.
Int J Pharm ; 632: 122554, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36586637

RESUMO

Dissolution testing is important in assessing the in vitro drug release performance for oral administration dosage forms. However, currently, a simple and efficient in vitro test to investigate critical factors that may impact the drug release and bioavailability at the development stage of a drug-loaded nanoemulsion (NE) is lacking. Thus, in this study, we developed a new combined biphasic and modified cylinder (BP + MC) method to evaluate the dissolution profile of NEs. Flubendazole (FLZ), a Biopharmaceutical Classification System (BCS) Class II drug, offers a new prospective for drug repositioning for treating lung cancer and cryptococcal meningitis. We compared the drug release profiles of three different FLZ formulations (micronized as a suspension, loaded in NE, and solubilized in oil) by using three different methods (dialysis bag, modified cylinder method, and a new BP + MC method). The results showed potential higher drug release of FLZ from the suspension compared to FLZ-loaded NE at pH 1.2, and higher drug release from FLZ-loaded NE compared to other forms in octanol phase. These results correlate well with the in vivo test performed in mice carried out in our previous works. Furthermore, the partition mechanism of the drug released from the NE is discussed in-depth in this article, as well as the advantage of drug-loaded NEs over other preparations in creating supersaturable conditions. Based on the results, we provide new insights into how dissolution methods for a poorly water-solubility drug can be designed. Therefore, we present this new combined BP + MC method as a potential new discriminative dissolution test for future studies when developing drug-loaded NE and comparing with other dosage forms.


Assuntos
Solubilidade , Camundongos , Animais , Preparações Farmacêuticas , Estudos Prospectivos , Liberação Controlada de Fármacos , Composição de Medicamentos , Administração Oral
6.
Braz. J. Pharm. Sci. (Online) ; 59: e22099, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1439517

RESUMO

Abstract In this study, the manufacturing process of lamivudine (3TC) and zidovudine (AZT) tablets (150+300 mg respectively) was evaluated using statistical process control (SPC) tools. These medicines are manufactured by the Fundação para o Remédio Popular "Chopin Tavares de Lima" (FURP) laboratory, and are distributed free of charge to patients infected with HIV by the Ministry of Health DST/AIDS national program. Data of 529 batches manufactured from 2012 to 2015 were collected. The critical quality attributes of weight variation, uniformity of dosage units, and dissolution were evaluated. Process stability was assessed using control charts, and the capability indices Cp, Cpk, Pp, and Ppk (process capability; process capability adjusted for non-centered distribution; potential or global capability of the process; and potential process capability adjusted for non-centered distribution, respectively) were evaluated. 3TC dissolution data from 2013 revealed a non-centered process and lack of consistency compared to the other years, showing Cpk and Ppk lower than 1.0 and the chance of failure of 2,483 in 1,000,000 tablets. Dissolution data from 2015 showed process improvement, revealed by Cpk and Ppk equal to 2.19 and 1.99, respectively. Overall, the control charts and capability indices showed the variability of the process and special causes. Additionally, it was possible to point out the opportunities for process changes, which are fundamental for understanding and supporting a continuous improvement environment.


Assuntos
Comprimidos/análise , Zidovudina/agonistas , HIV/patogenicidade , Lamivudina/agonistas , Pacientes/classificação , Gestão da Qualidade Total/organização & administração , Honorários e Preços/estatística & dados numéricos , Laboratórios/classificação , Manufaturas/provisão & distribuição
7.
Pharmaceutics ; 14(10)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36297656

RESUMO

Bacterial conjunctivitis significantly impacts public health, including more than one-third of eye diseases reported worldwide. It is an infection caused by various aerobic and anaerobic bacteria and is highly contagious. Therefore, it has a high incidence of bacterial resistance to the antibiotics commonly used for treatment. Among the most recent antibiotics, besifloxacin is a fourth-generation fluoroquinolone antibiotic indicated exclusively for topical ophthalmic use. Due to its importance in treating bacterial conjunctivitis and its low solubility in water, limiting its efficacy, a nanotechnology-based drug delivery preparation was developed to overcome this hurdle. Besifloxacin nanocrystals were prepared by small-scale wet milling and response surface methodology, using Povacoat® as a stabilizer. The particle's average hydrodynamic diameter (Z-ave) was approximately 550 nm (17 times smaller than raw material), with a polydispersity index (PdI) of less than 0.2. The saturation solubility increased about two times compared to the raw material, making it possible to increase the dissolution rate of this drug substance, potentially improving its bioavailability and safety. The optimized preparation was stable under an accelerated stability study (90 days). The Z-ave, PZ, PdI, and content did not alter significantly during this period. Furthermore, the 0.6% m/m besifloxacin nanocrystals at the maximum dose and the Povacoat® stabilizer did not show toxicity in Galleria mellonella larvae. The innovative ophthalmic preparation minimum inhibitory concentration (MIC) was 0.0960 µg/mL and 1.60 µg/mL against Staphylococcus aureus and Pseudomonas aeruginosa, respectively, confirming in vitro efficacy. Therefore, besifloxacin nanocrystals revealed the potential for reduced dosing of the drug substance, with a minor occurrence of adverse effects and greater patient adherence to treatment.

9.
AAPS PharmSciTech ; 23(4): 102, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35378669

RESUMO

Topical microemulsion (ME) might provide a novel and advanced transdermal delivery system due to the enhances of drug solubility and permeability across the stratum corneum. Foams are topical delivery systems that have excellent patient compliance, acceptability, and preference. Therefore, this study aimed to investigate a foamable microemulsion as an alternative topical and transdermal dosage form for diclofenac sodium (DS). The physicochemical properties (optical clarity, percentage transmittance, homogeneity, consistency of formulation, particle size, zeta potential, conductivity, viscosity, and morphology, etc.) of the DS-loaded ME were investigated. The foam stability of both drug-free ME and DS-loaded ME was measured. The foam quality was evaluated, and the chemical stability over 90 days was determined. Franz diffusion cells were employed to assess the in vitro drug release of a foamed DS-loaded ME and compared with a commercial topical product. A foamable and stable DS-loaded ME that maintained small particle sizes and constant zeta potential and was transparent and translucent in appearance after 90 days was successfully produced. The foam of the DS-loaded ME was physically more stable compared to the drug-free foam. The foam had an increased drug release rate compared to the commercial product. The foamable DS-loaded ME has a great potential to enhance the transdermal delivery of DS after topical administration. Foamed DS-loaded ME is a promising alternative to the current topical formulation of DS.


Assuntos
Diclofenaco , Administração Cutânea , Diclofenaco/química , Liberação Controlada de Fármacos , Emulsões/química , Humanos , Solubilidade
10.
Int J Pharm ; 621: 121782, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35489605

RESUMO

According to the World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC), bacterial infections are one of the greatest threats to global health, food production, and life expectancy. In this sense, the development of innovative formulations aiming at greater therapeutic efficacy, safety, and shorter treatment duration compared to conventional products is urgently needed. Lipid-based nanocarriers (LBNs) have demonstrated the potential to enhance the effectiveness of available antibiotics. Among them, liposome, nanoemulsion, solid lipid nanoparticle (SLN), and nanostructured lipid carrier (NLC) are the most promising due to their solid technical background for laboratory and industrial production. This review describes recent advances in developing antibiotic-loaded LBNs against susceptible and resistant bacterial strains and biofilm. LBNs revealed to be a promising alternative to deliver antibiotics due to their superior characteristics compared to conventional preparations, including their modified drug release, improved bioavailability, drug protection against chemical or enzymatic degradation, greater drug loading capacity, and biocompatibility. Antibiotic-loaded LBNs can improve current clinical drug therapy, bring innovative products and rescue discarded antibiotics. Thus, antibiotic-loaded LBNs have potential to open a window of opportunities to continue saving millions of lives and prevent the devastating impact of bacterial infection.


Assuntos
Infecções Bacterianas , Nanopartículas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Portadores de Fármacos/uso terapêutico , Humanos , Lipídeos , Lipossomos
11.
Int J Pharm ; 614: 121456, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35017024

RESUMO

The FDA-approved anthelmintic flubendazole has shown potential to be repositioned to treat cancer and dry macular degeneration; however, its poor water solubility limits its use. Amorphous solid dispersions may overcome this challenge, but the balance of excipients may impact the preparation method and drug release. The purpose of this study was to evaluate the influence of adjuvants and drug loading on the development of an amorphous solid dispersion of flubendazole-copovidone by hot-melt extrusion. The drug, copovidone, and adjuvants (magnesium stearate and hydroxypropyl cellulose) mixtures were statistically designed, and the process was performed in a twin-screw extruder. The study showed that flubendazole and copovidone mixtures were highly extrudable, except when drug loading was high (>40%). Furthermore, magnesium stearate positively impacted the extrusion and was more effective than hydroxypropyl cellulose. The extruded materials were evaluated by modulated differential scanning calorimetry and X-ray powder diffraction, obtaining positive amorphization and physical stability results. Pair distribution function analysis indicated the presence of drug-rich domains with medium-range order structure and no evidence of polymer-drug interaction. All extrudates presented faster dissolution (HCl, pH 1.2) than pure flubendazole, and both adjuvants had a notable influence on the dissolution rate. In conclusion, hot-melt extrusion may be a viable option to obtain stable flubendazole:copovidone amorphous dispersions.


Assuntos
Química Farmacêutica , Excipientes , Varredura Diferencial de Calorimetria , Portadores de Fármacos , Composição de Medicamentos , Temperatura Alta , Mebendazol/análogos & derivados , Pirrolidinas , Solubilidade , Compostos de Vinila
12.
Eur J Pharm Sci ; 169: 106097, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34910988

RESUMO

Leishmaniasis, a neglected tropical disease, is prevalent in 98 countries with the occurrence of 1.3 million new cases annually. The conventional therapy for visceral leishmaniasis requires hospitalization due to the severe adverse effects of the drugs, which are administered parenterally. Buparvaquone (BPQ) showed in vitro activity against leishmania parasites; nevertheless, it has failed in vivo tests due to its low aqueous solubility. Though, lipid nanoparticles can overcome this holdback. In this study we tested the hypothesis whether BPQ-NLC shows in vivo activity against L. infantum. Two optimized formulations were prepared (V1: 173.9 ± 1.6 nm, 0.5 mg of BPQ/mL; V2: 232.4 ± 1.6 nm, 1.3 mg of BPQ/mL), both showed increased solubility up to 73.00-fold, and dissolution up to 83.29%, while for the free drug it was only 2.89%. Cytotoxicity test showed their biocompatibility (CC50 >554.4 µM). Besides, the V1 dose of 0.3 mg/kg/day for 10 days reduced the parasite burden in 83.4% ±18.2% (p <0.05) in the liver. BPQ-NLC showed similar leishmanicidal activity compared to miltefosine. Therefore, BPQ-NLC is a promising addition to the limited therapeutic arsenal suitable for leishmaniasis oral administration treatment.


Assuntos
Antiprotozoários , Leishmania infantum , Administração Oral , Antiprotozoários/uso terapêutico , Lipídeos , Lipossomos , Nanopartículas , Naftoquinonas
13.
Braz. J. Pharm. Sci. (Online) ; 58: e20767, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1420452

RESUMO

Abstract The second generation of H1 antihistamines from the piperidine group are often used for treating allergic diseases due to their action on histaminic receptors, the primary mediator of allergy. Moreover, the antihistamines have anti-inflammatory action, mediated through platelet-activating factor blocking activity. A simple and rapid capillary zone electrophoresis method was developed and validated for the determination of loratadine (LOR) and rupatadine (RUP) in tablets. The analyses were carried out using a fused silica capillary of 50.2 cm (40 cm effective length), 75 µm i.d. The background electrolyte was composed of boric acid 35 mmol/L, pH 2.5. Voltage of 20 kV, hydrodynamic injection of 3447.3 Pa for 3s, temperature at 25 ºC, and UV detection at 205 nm were applied. Electrophoretic separation was achieved at 1.8 and 2.8 min for RUP and LOR, respectively. The method was linear for both drugs in a range of 50.0 to 400.0 µg/mL (r>0.99). The limits of detection and quantification were 46.37 and 140.52 µg/mL, for LOR and 29.60 and 89.69 µg/mL for RUP respectively. The precision was less than 5.0 % for both drugs. The average recovery was approximately 100 %. The proposed novel method can significantly contribute to the rapid detection of counterfeit products and in quality control of drug products containing antihistamines


Assuntos
Loratadina/antagonistas & inibidores , Eletroforese Capilar/métodos , Antagonistas dos Receptores Histamínicos H1/farmacologia , Controle de Qualidade , Capilares/anormalidades , Preparações Farmacêuticas/análise , Métodos de Análise Laboratorial e de Campo
14.
J Pharm Pharm Sci ; 24: 533-547, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34694988

RESUMO

The uniqueness of structure and physiology of the lymphatic system make it challenging to delineate all its contributions in the maintenance of our health. However, in the past two decades, the understanding of the importance of the function of this system has evolved and more appreciation has been drawn to the distinctive role it plays in health and disease. The lymphatic system has been linked to the pathophysiology of numerous ailments including cancer, various metabolic diseases, inflammatory conditions, and infections. Moreover, it has also been revealed that lymphatic targeted formulations can enhance the delivery of drugs through the lymphatic system to the bloodstream, bypassing the hepatic first-pass metabolism if taken orally, thus increasing the bioavailability, and improving the pharmacokinetic and toxicological profiles in general. Engineering lymphotropic preparations requires the understanding of many factors, the most important one being that of the physiological environment which they will encounter. Therefore, in this review, we detail the basic structure of the lymphatic system, then highlight the therapeutic and the pharmacokinetic benefits of drug delivery into the lymphatic system. The criteria for drugs and formulations used for lymphotropic delivery are also detailed with a contemporary overview of various studies undertaken in this field.


Assuntos
Sistema Linfático/fisiopatologia , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos , Humanos , Linfonodos/efeitos dos fármacos , Linfonodos/fisiopatologia , Sistema Linfático/efeitos dos fármacos , Farmacocinética
15.
Antioxidants (Basel) ; 10(7)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206935

RESUMO

Carotenoids and coenzyme Q10 are naturally occurring antioxidant compounds that are also found in human skin. These bioactive compounds have been the focus of considerable research due to their antioxidant, anti-inflammatory, and photoprotective properties. In this review, the current state of the art in the encapsulation of carotenoids and coenzyme Q10 in lipid nanoparticles to improve their bioavailability, chemical stability, and skin absorption is discussed. Additionally, the main findings are highlighted on the cytotoxic and photoprotective effects of these systems in the skin.

16.
Int J Pharm ; 602: 120611, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33872710

RESUMO

The levitation of samples in an acoustic field has been of interest in the preparation and study of amorphous solid dispersions (ASD). Here, niclosamide-polymer solutions were levitated in a multi-emitter single-axis acoustic levitator and analyzed for 10 min at a High-resolution synchrotron X-ray powder diffraction beamline. This assembly enabled high-quality and fast time-resolved measurements with microliter sample size and measurement of solvent evaporation and recrystallization of niclosamide (NCL). Polymers HPMCP-55S, HPMCP-50, HPMCP-55, Klucel®, and poloxamers were not able to form amorphous dispersions with NCL. Plasdone® and Soluplus® demonstrated excellent properties to form NCL amorphous dispersions, with the last showing superior solubility enhancement. Furthermore, this fast levitation polymer screening showed good agreement with results obtained by conventional solvent evaporation screening evaluated for five days in a stability study, carried out at 40 °C/75% RH. The study showed that acoustic levitation and high-resolution synchrotron combination opens up a new horizon with great potential for accelerating ASD formulation screening and analysis.


Assuntos
Niclosamida , Síncrotrons , Acústica , Química Farmacêutica , Pós , Solubilidade , Difração de Raios X , Raios X
17.
Pharm Res ; 38(2): 199-211, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33604785

RESUMO

Currently, the use of Traditional Chinese Medicine (TCM) for healthy living in daily practice is widely accepted across the world. However, not much attention has been paid to the particular characteristics of TCM "pills", one of the classic dosage forms in TCM. For a better understanding, this review was undertaken to provide a modern pharmaceutical overview of pills. Over many centuries, pills have been developed in different types (honeyed pill, water-honeyed pill, watered pill, pasted pill, waxed pill, concentrated pill, and dripping pill) to achieve varying intended TCM release patterns. It suggests that knowledge relating to the impact of binders and excipients on drug release from TCM pills can be traced back to before dissolution testing was invented. Therefore, although Pills may be considered as an ancient and outdated dosage form compared to current drug delivery systems, they have surprisingly modern pharmaceutical properties that is highlighted in this article. In addition, this review found that the quality control standards for TCM pill are globally substantially different. Hence, greater effort should be taken to establish an internationally harmonized and proper standard to safeguard the quality of this dosage form and to ensure the alignment with TCM use.


Assuntos
Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Medicamentos de Ervas Chinesas/administração & dosagem , Medicina Tradicional Chinesa/métodos , Liberação Controlada de Fármacos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacocinética , Excipientes/química , Humanos
18.
AAPS PharmSciTech ; 22(2): 54, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33475891

RESUMO

This work describes an exploratory experimental and in silico study of the influence of polymorphism, particle size, and physiology on the pharmacokinetics of lercanidipine hydrochloride (LHC). Equilibrium and kinetic solubility studies were performed on LHC forms I and II, as a function of pH and buffer composition. GastroPlus® was used to evaluate the potential effect of solubility differences due to polymorphism, particle size, and physiological conditions, on the drug pharmacokinetics. The results indicated that solubilities of LHC polymorphs are strongly dependent on the composition and pH of the buffer media. The concentration ratio (CI/CII) is particularly large for chloride buffer (CI/CII = 3.3-3.9) and exhibits a slightly decreasing tendency with the pH increase for all other buffers. Based on solubility alone, a higher bioavailability of form I might be expected. However, exploratory PBPK simulations suggested that (i) under usual fasted (pH 1.3) and fed (pH 4.9) gastric conditions, the two polymorphs have similar bioavailability, regardless of the particle size; (ii) at high gastric pH in the fasted state (e.g., pH 3.0), the bioavailability of form II can be considerably lower than that of form I, unless the particle size is < 20 µm. This study demonstrates the importance of investigating the effect of the buffer nature when evaluating the solubility of ionizable polymorphic substances. It also showcases the benefits of using PBPK simulations, to assess the risk and pharmacokinetic relevance of different solubility and particle size between crystal forms, for diverse physiological conditions.


Assuntos
Di-Hidropiridinas/química , Disponibilidade Biológica , Di-Hidropiridinas/farmacocinética , Humanos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Solubilidade
19.
Eur J Pharm Sci ; 158: 105654, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33253884

RESUMO

Anti-inflammatory drugs have been prescribed extensively for a wide range of diseases. Combined with over-the-counter use, approximately 30 billion doses of non-steroidal inflammatory drugs (NSAIDs) are consumed annually in the USA. The global market of glucocorticoids (GCs) is forecast to reach US$ 8.6 billion by 2025. Severe adverse effects have been reported for NSAIDs, GCs, and COX-2 selective NSAIDs (COXIBs). Furthermore, the overwhelming majority of these drug substances are BCS class II, which limits their bioavailability due to poor water solubility. Drug nanocrystals, a carrier-free nanosystem, can increase saturation solubility, dissolution rate, and the mucoadhesiveness of these drugs. The enhancement of these properties was highlighted in our findings. These features improve the efficacy and safety of anti-inflammatory drugs. In this review, we show that drug nanocrystals are an attractive strategy that contributes to an important shift in the development of innovative products for different routes of administration. The possibility of targeting can minimize the adverse effects and improve the efficacy in the management of inflammatory conditions. We comprehensively review the critical quality attributes (CQAs) in the anti-inflammatory drug nanocrystals preparation, which are fundamental to developing a successful marketable product. Despite the advantages, maintaining properties such as average particle size, surface properties, and physicochemical stability of these preparations during shelf life poses challenges to be overcome.


Assuntos
Nanopartículas , Preparações Farmacêuticas , Anti-Inflamatórios não Esteroides , Disponibilidade Biológica , Inibidores de Ciclo-Oxigenase 2 , Solubilidade
20.
Int J Pharm ; 589: 119831, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32877729

RESUMO

Posterior segment eye diseases affect more than 300 million patients worldwide resulting in severe visual impairment. The treatments available are invasive, costly, present irregular effectiveness, and cause serious adverse effects. These drawbacks significantly reduce patient compliance. In the last decade, solid lipid nanoparticle (SLN) and nanostructured lipid carrier (NLC) have shown potential as innovative carriers for lipophilic drug substances to overcome hurdles in treating the eye posterior segment. This review shows the advantages of these formulations, focusing on their compatibility with ocular tissues, which increases the internalization of the drug substances. Additionally, SLN and NLC can reduce the clearance by the eye's protective mechanisms due to adhesive properties related to nanometric size. Therefore, these preparations may allow the treating of several ophthalmic diseases by topical administration, increasing the interval between doses. This feature can decrease adverse effects and enhance efficacy, ultimately improving patient compliance. Thus, this critical review presents the performance of the in vitro, ex vivo, and in vivo assays that support the potential of SLN and NLC to treat diseases of the posterior segment of the eye. These nanoparticles have shown to be promising alternative towards a major shift in developing ophthalmic products.


Assuntos
Nanopartículas , Nanoestruturas , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Humanos , Lipídeos
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