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1.
Drug Dev Res ; 85(3): e22191, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685610

RESUMO

Psoriasis is a chronic inflammatory and proliferative skin disease that causes pathological skin changes and has a substantial impact on the quality of patient life. Apremilast was approved by the US Food and Drug Administration as an oral medication for psoriasis and is beneficial in mild to moderate conditions for chronic usage. However, 5%-7% of withdrawals were reported due to severe side effects. To address the issue, a localized drug delivery strategy via the topical route may be a viable approach. However, poor physicochemical properties make it vulnerable to passing through the skin, requiring a specialized drug delivery system to demonstrate its full potential via a topical route like lecithin organogel. The formulation was optimized by screening the suitable lecithin type and non-polar solvents based on the gel formation ability of lecithin and the solubility of apremilast in the solvent. The pseudo-ternary diagram was used to optimize the water content required to form the gel. The optimized gel was found to be shear thinning characterized for rheological parameters, in-vitro diffusion studies, and in-vitro skin distribution studies. Preclinical studies in Imiquimod-induced mice showed a better reduction in severity index, cytokine levels, and epidermal hyperplasia from the lecithin organogel group compared to the apremilast oral administration and marketed standard topical gel group. Based on these results, lecithin organogel can be considered a promising approach to deliver molecules like apremilast by topical route in psoriatic-like conditions.


Assuntos
Sistemas de Liberação de Medicamentos , Géis , Lecitinas , Psoríase , Talidomida , Talidomida/análogos & derivados , Psoríase/tratamento farmacológico , Lecitinas/química , Animais , Camundongos , Talidomida/administração & dosagem , Talidomida/química , Talidomida/farmacocinética , Absorção Cutânea/efeitos dos fármacos , Pele/metabolismo , Pele/efeitos dos fármacos , Administração Cutânea , Administração Tópica , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Imiquimode/administração & dosagem , Masculino
2.
J Drug Target ; 32(2): 186-199, 2024 12.
Artigo em Inglês | MEDLINE | ID: mdl-38133596

RESUMO

Niclosamide (NCL) is repurposed to treat inflammatory bowel disease due to its anti-inflammatory properties and potential to reduce oxidative stress. This therapeutic activity remains challenging if administered directly due to its low solubility and high recrystallization tendency in gastric pH. Solid dispersions using pH-dependent polymer will be a better idea to improve the solubility, dissolution and targeted delivery at the colon. Hot melt extrusion was used to formulate a solid dispersion with 30% NCL utilising hydroxypropyl methylcellulose acetate succinate as a pH-dependent polymer. In vitro drug release studies revealed formulation (F1) containing 10%w/w Tween 80 showed minimal release (2.06%) at the end of 2 h, followed by 47.87% and 82.15% drug release at 6 h and 14 h, respectively, indicating the maximum amount of drug release in the colon. The drug release from the formulations containing no plasticiser and 5%w/w plasticiser was comparable to the pure crystalline drug (approximately 25%). Solid-state analysis confirmed particle conversion of crystalline NCL to amorphous form, and the optimised formulation was stable for 6 months without significant changes in dissolution profile. In contrast to pure NCL, the F1 formulation substantially reduced the disease activity index, colonic inflammation, histological alterations and oxidative damage in colitis mice. These findings reveal that the prepared formulation can potentially deliver the drug locally at the colon, making it an effective tool in treating ulcerative colitis.


Assuntos
Colite Ulcerativa , Polímeros , Camundongos , Animais , Composição de Medicamentos , Niclosamida/farmacologia , Colite Ulcerativa/tratamento farmacológico , Solubilidade , Preparações Farmacêuticas , Concentração de Íons de Hidrogênio
3.
Pharmaceutics ; 15(7)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37513995

RESUMO

Typically, antibody-drug conjugates (ADCs) are made up of a humanized antibody and a small-molecule medication connected by a chemical linker. ADCs' ability to deliver cytotoxic agents to the specific site with reduced side effects showed promising results in oncology. To date, fourteen ADCs have been approved by the US Food and Drug Administration, and approximately 297 ADCs are in pre-clinical/clinical stages in the oncology area. Inspired by these outcomes, a few scientists explored the potential of antibody-drug conjugates in non-oncological conditions such as arthritis, myasthenia gravis, immunological disorders, and kidney failure. However, there are limited data available on the non-oncological applications of antibody-drug conjugates. This current review focuses on the non-oncological applications of antibody-drug conjugates, their developmental studies, testing procedures, in vitro evaluations, and pre-clinical testing. Additionally, a summary of the restrictions, difficulties, and prospects for ADCs in non-oncological applications is provided.

4.
Eur J Drug Metab Pharmacokinet ; 48(2): 189-199, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36800055

RESUMO

BACKGROUND AND OBJECTIVE: Many naturally available dietary molecules such as curcumin have not seen the market due to poor solubility, bioavailability, and photodegradability. Successful development of a lipid-based dry emulsion may overcome these issues and help in reaching the markets for natural dietary molecules such as curcumin. The current study aims to develop a dry emulsion formulation of curcumin using natural oil and evaluate its dissolution, photostability, pharmacokinetics, and anti-inflammatory activity. METHODS: Dry emulsions were prepared using emu oil and corn oil as the lipid phase, Caproyl 90 and Cremophor RH 40 as surfactants, and dextrin as a hydrophilic carrier. RESULTS: Microscopic studies showed the formation of spherical porous particles, and solid-state characterization using differential scanning calorimetry and powder X-ray diffraction showed the conversion of curcumin to an amorphous form. About 80% drug release was observed from formulation, whereas pure drug showed only 50% drug release in 30 min. In vivo pharmacokinetic studies showed fivefold improvement in the maximum concentration of curcumin in plasma (Cmax) and sevenfold improvement in the area under the concentration-time curve of curcumin from emu oil formulation compared with pure curcumin. Significant differences were observed in the anti-inflammatory activity of curcumin dry emulsion and plain curcumin. Emu-oil-based formulations showed synergistic anti-inflammatory activity over corn-oil-based formulations with improved photostability. CONCLUSION: The present study suggests that the dry emulsion may enhance the bioavailability with synergistic anti-inflammatory activity and photostability of curcumin when given orally.


Assuntos
Curcumina , Ratos , Animais , Curcumina/farmacocinética , Ratos Sprague-Dawley , Emulsões/química , Sistemas de Liberação de Medicamentos , Anti-Inflamatórios/farmacologia , Disponibilidade Biológica , Excipientes/química , Solubilidade
5.
J Liposome Res ; 33(3): 268-282, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36594184

RESUMO

The emerging drug resistance to the approved first-line drug therapy leads to clinical failure in cancer. Drug repurposing studies lead to the identification of many old drugs to be used for cancer treatment. Combining the repurposed drugs (niclosamide) with first-line therapy agents like erlotinib HCl showed improved efficacy by inhibiting erlotinib HCl acquired resistance. But there is a need to develop a sensitive, accurate, and excellent analytical method and drug delivery system for successfully delivering drug combinations. In the current study, an HPLC method was developed and validated for the simultaneous estimation of niclosamide and erlotinib HCl. The retention time of niclosamide and erlotinib hydrochloride was 6.48 and 7.65 min at 333 nm. The developed method was rapid and sensitive to separating the two drugs with reasonable accuracy, precision, robustness, and ruggedness. A Plackett-Burman (PBD) screening design was used to identify the critical parameters affecting liposomal formulation development using particle size, size distribution, zeta potential, and entrapment efficiency as the response. Lipid concentration, drug concentration, hydration temperature, and media volume were critical parameters affecting the particle size, polydispersity index (PDI), ZP, and %EE of the liposomes. The optimized NCM-ERL liposomes showed the particle size (126.05 ± 2.1), PDI (0.498 ± 0.1), ZP (-16.2 ± 0.3), and %EE of NCM and ERL (50.04 ± 2.8 and 05.42 ± 1.3). In vitro release studies indicated the controlled release of the drugs loaded liposomes (87.06 ± 9.93% and 42.33 ± 0.89% in 24 h).


Assuntos
Lipossomos , Niclosamida , Cloridrato de Erlotinib/farmacologia , Cromatografia Líquida de Alta Pressão , Liberação Controlada de Fármacos , Tamanho da Partícula
6.
Food Biosci ; 50: 101977, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36059903

RESUMO

The novel enveloped ß-coronavirus SARS-CoV-2 (COVID-19) has offered a surprising health challenge all over the world. It develops severe pneumonia leading to acute respiratory distress syndrome (ARDS). Like SARS-COV-2, other encapsulated viruses like HIV, HSV, and influenza have also offered a similar challenge in the past. In this regard, many antiviral drugs are being explored with varying degrees of success to combat the associated pathological conditions. Therefore, upon scientific validation & development, these antiviral phytochemicals can attain a futuristic nutraceutical prospect in managing different encapsulated viruses. Houttuynia cordata (HC) is widely reported for activities such as antioxidant, anti-inflammatory, and antiviral properties. The major antiviral bioactive components of HC include essential oils (methyl n-nonyl ketone, lauryl aldehyde, capryl aldehyde), flavonoids (quercetin, rutin, hyperin, quercitrin, isoquercitrin), and alkaloids (norcepharadione B) & polysaccharides. HC can further be explored as a potential nutraceutical agent in the therapy of encapsulated viruses like HIV, HSV, and influenza. The review listed various conventional and green technologies that are being employed to extract potent phytochemicals with diverse activities from the HC. It was indicated that HC also inhibited molecular targets like 3C-like protease (3CLPRO) and RNA-dependent RNA polymerase (RdRp) of COVID-19 by blocking viral RNA synthesis and replication. Antioxidant and hepatoprotective effects of HC have been evident in impeding complications from marketed drugs during antiviral therapies. The use of HC as a nutraceutical is localized within some parts of Southeast Asia. Further technological advances can establish it as a nutraceutical-based functional food against pathogenic enveloped viruses like COVID 19.

7.
Colloids Surf B Biointerfaces ; 211: 112305, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34998178

RESUMO

Erlotinib-based EGFR targeted therapy has proven significant clinical improvement against non-small cell lung cancer (NSCLC). However, the anticancer activity of Erlotinib (Ertb) is limited by the development of Ertb resistance and possess a challenge to clinicians and patients. To explore a better therapeutic strategy, we evaluated Ertb in combinations with different natural products. We identified that Ertb and Quercetin (Quer) combination is more synergistic against A549 and NCI H460 cells compared to Ertb with Fisetin/Carnosic acid/Luteolin. To further improve the efficacy and overcome the limitation of free therapeutics, Ertb and Quer loaded solid lipid nanoparticles (EQNPs) were prepared using Chitosan-MA-TPGS polymer by hot homogenization method. The drug-loaded nanoparticles (NPs) have shown high encapsulation efficiency (77% Ertb and 71.4% Quer) as well as small particle size of 87.3 ± 0.78 nm and positive zeta potential + 13.4 ± 1.12 mV. At pH 5.5, Ertb and Quer were released at their highest levels. We found that, EQNPs decreased the expression of P-glycoprotein (P-gp) and nuclear epidermal growth factor receptor (nEGFR). EQNPs increased the uptake of Ertb and Quer, and apoptosis induction in Ertb resistant A549/ER cells. Further, in vivo EQNPs formulation have shown increased uptake of nanoparticles in the lung tissue and significantly reduced the expression of nEGFR. Thus, EQNPs may be developed as a targeted medicine with minimum side effects for treatment of NSCLC to improve the quality of life and survival of NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas , Apoptose , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/genética , Receptores ErbB/metabolismo , Cloridrato de Erlotinib/farmacologia , Humanos , Lipossomos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Nanopartículas/uso terapêutico , Fosfatidilinositol 3-Quinases/farmacologia , Fosfatidilinositol 3-Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-akt , Qualidade de Vida , Quercetina/farmacologia
8.
AAPS PharmSciTech ; 22(5): 192, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34184160

RESUMO

Neurodegenerative diseases like Alzheimer's disease require treatment where it is essential for drug to reach brain. Nose to brain delivery of drugs enables direct transport to brain bypassing blood brain barrier. Imatinib mesylate, an anti-cancer agent, was found to have potential anti-Alzheimer's activity and thus repurposed for the same. However, the drug has severe side effects, poor brain bioavailability which may hinder effective treatment of Alzheimer's disease. In the current work, imatinib mesylate-loaded liposomes were prepared with particle size below 150 nm with sustained drug release up to 96 h. The liposomal drug formulation was compared with plain drug solution for cytotoxicity on N2a cells and did not show any kind of toxicity at concentrations up to 25 µg/mL. The nanocarrier formulation was then evaluated for brain deposition by nose to brain administration in comparison with drug solution in rats. The liposomes effectively improved the brain deposition of drug in brain from formulation compared to pure drug solution as indicated by AUC from in vivo experiments. These results indicate that the nose to brain delivery of liposomal imatinib mesylate improved the drug deposition and residence time in brain compared to drug solution administered through oral and intranasal routes.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Desenvolvimento de Medicamentos/métodos , Mesilato de Imatinib/administração & dosagem , Mesilato de Imatinib/farmacocinética , Administração Intranasal , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Avaliação Pré-Clínica de Medicamentos/métodos , Mesilato de Imatinib/síntese química , Lipossomos , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley
9.
Int J Pharm ; 605: 120819, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34166727

RESUMO

Targeted delivery of chemotherapeutic agents is considered a prominent strategy for the treatment of cancer due to its site-specific delivery, augmented penetration, bioavailability, and improved therapeutic efficiency. In the present study, we employed UniPR126 as a carrier in a mixed nanomicellar delivery system to target and deliver anticancer drug NIC specifically to cancer cells via EphA2 receptors as these receptors are overexpressed in cancer cells but not in normal cells. The specificity of the carrier was confirmed from the significant enhancement in the uptake of coumarin-6 loaded mixed nanomicelle by EphA2 highly expressed PC-3 cells compared to EphA2 low expressed H4 cells. Further, niclosamide-loaded lithocholic acid tryptophan conjugate-based mixed nanomicelle has shown significant synergistic cytotoxicity in PC-3 but not in H4 cells. In vivo anticancer efficacy data in PC-3 xenograft revealed a significant reduction in the tumor volume (66.87%) with niclosamide-loaded lithocholic acid tryptophan conjugate nanomicelle, where pure niclosamide showed just half of the activity. Molecular signaling data by western blotting also indicated that niclosamide-loaded lithocholic acid tryptophan conjugate nanomicelle interfered with the EphA2 receptor signaling and inhibition of the Wnt/beta-catenin pathway and resulted in the synergistic anticancer activity compared to niclosamide pure drug.


Assuntos
Neoplasias da Próstata , Receptor EphA2 , Linhagem Celular Tumoral , Humanos , Ácido Litocólico , Masculino , Micelas , Niclosamida , Neoplasias da Próstata/tratamento farmacológico , Receptor EphA2/metabolismo , Triptofano , Via de Sinalização Wnt
10.
Eur J Pharm Sci ; 139: 105048, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31446077

RESUMO

Co amorphous systems are supersaturated drug delivery systems which offer a basic platform for delivery of multicomponent adducts (combination of more than one active pharmaceutical ingredient (API)) and/or as a fixed dose combination therapy, in addition to their potential to improve the apparent solubility, dissolution rate and ultimately bioavailability of poorly water soluble APIs. In the present work, a new drug-drug co amorphous system namely valsartan-nifedipine was prepared by quench cooling technique. Prepared co amorphous system was characterized for its solid state behavior with the help of Fourier Transform Infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Powder X Ray Diffractometry (PXRD). The optimized co amorphous system was stable for 1 month when exposed to accelerated stability condition (40 ±â€¯2 °C and 75 ±â€¯5% RH). The improved stability of amorphous nifedipine in co amorphous system was attributed to improved miscibility and intra and intermolecular non-covalent interactions mainly due to presence of hydrogen bonding between valsartan and nifedipine which was studied by FTIR analysis. Co amorphous systems were evaluated by mainly in vitro dissolution and in vivo benefit. In vitro dissolution study showed nearly 5.66 folds and 1.61 folds improvement which was translated to 3.63 and 2.19 times enhancement in vivo Cmax for nifedipine and valsartan respectively.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II , Bloqueadores dos Canais de Cálcio , Nifedipino , Valsartana , Bloqueadores do Receptor Tipo 1 de Angiotensina II/química , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacocinética , Animais , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacocinética , Combinação de Medicamentos , Composição de Medicamentos , Liberação Controlada de Fármacos , Feminino , Nifedipino/química , Nifedipino/farmacocinética , Ratos Sprague-Dawley , Valsartana/química , Valsartana/farmacocinética
11.
Carbohydr Polym ; 212: 252-259, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30832855

RESUMO

Niclosamide, previously used as an anthelmintic drug is currently being repurposed for its anticancer activity. Niclosamide is a brick like biopharmaceutical classification system (BCS) class II drug with poor aqueous solubility and dissolution consequently leading to low bioavailability. By considering the physicochemical properties and geometry of niclosamide, inclusion complex with cyclodextrin was prepared by freeze drying method and characterized using FT-IR, DSC, PXRD, and 1HNMR. In silico molecular modeling study was performed to study the possible interactions between niclosamide and cyclodextrin. The anticancer activity of niclosamide formulation was evaluated through in vitro cell cytotoxicity study using various cancer cell lines. The potential of niclosamide complex for improvement of the bioavailability was evaluated in male BALB/c mice. In vitro cytotoxicity studies indicated significantly higher cytotoxicity at lower concentrations and the pharmacokinetic studies showed significant improvement in Cmax and Tmax of niclosamide from cyclodextrin complex in comparison to pure niclosamide alone.


Assuntos
Antineoplásicos/síntese química , Ciclodextrinas/síntese química , Composição de Medicamentos/métodos , Reposicionamento de Medicamentos/métodos , Niclosamida/síntese química , Animais , Anticestoides/síntese química , Anticestoides/metabolismo , Antineoplásicos/metabolismo , Ciclodextrinas/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Niclosamida/metabolismo
12.
Drug Dev Ind Pharm ; 43(4): 611-617, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28005442

RESUMO

OBJECTIVE: Olmesartan medoxomil (OLM) is an antihypertensive drug with low oral bioavailability (28%) resulting from poor aqueous solubility, presystemic metabolism and P-glycoprotein mediated efflux. The present investigation studies the role of lipid nanocarriers in enhancing the OLM bioavailability through oral delivery. MATERIALS AND METHODS: Solid lipid nanoparticles (SLN) were prepared by solvent emulsion-evaporation method. Statistical tools like regression analysis and Pareto charts were used to detect the important factors effecting the formulations. Formulation and process parameters were then optimized using mean effect plot and contour plots. The formulations were characterized for particle size, size distribution, surface charge, percentage of drug entrapped in nanoparticles, drug-excipients interactions, powder X-ray diffraction analysis and drug release in vitro. RESULTS AND DISCUSSION: The optimized formulation comprised glyceryl monostearate, soya phosphatidylcholine and Tween 80 as lipid, co-emulsifier and surfactant, respectively, with an average particle size of 100 nm, PDI 0.291, zeta potential of -23.4 mV and 78% entrapment efficiency. Pharmacokinetic evaluation in male Sprague Dawley rats revealed 2.32-fold enhancement in relative bioavailability of drug from SLN when compared to that of OLM plain drug on oral administration. CONCLUSION: In conclusion, SLN show promising approaches as a vehicle for oral delivery of drugs like OLM.


Assuntos
Lipídeos/química , Nanopartículas/química , Olmesartana Medoxomila/administração & dosagem , Olmesartana Medoxomila/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Administração Oral , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacocinética , Disponibilidade Biológica , Química Farmacêutica/métodos , Portadores de Fármacos/química , Estabilidade de Medicamentos , Emulsões/química , Emulsões/farmacocinética , Excipientes/química , Masculino , Olmesartana Medoxomila/farmacocinética , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Solubilidade , Tensoativos/química
13.
Int J Pharm ; 506(1-2): 222-36, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27109049

RESUMO

Curcumin and emu oil derived from emu bird (Dromaius novaehollandiae) has shown promising results against inflammation. However, the delivery of curcumin is hindered due to low solubility and poor permeation. In addition, till date the role of emu oil in drug delivery has not been explored systemically. Hence, the current investigation was designed to evaluate the anti-inflammatory potential of curcumin in combination with emu oil from a nanoemulgel formulation in experimental inflammation and arthritic in vivo models. Nanoemulsion was prepared using emu oil, Cremophor RH 40 and Labrafil M2125CS as oil phase, surfactant and co-surfactant. The optimized curcumin loaded nanoemulsion with emu oil was incorporated into carbopol gel for convenient application by topical route. The anti-inflammatory efficacy was evaluated in carrageenan induced paw edema and FCA induced arthritic rat model in terms of paw swelling, weight indices of the liver and spleen, pathological changes in nuclear factor kappa B, iNOS, COX-2 expression and inflammatory cytokines. Arthritic scoring, paw volume, biochemical, molecular, radiological and histological examinations indicated significant improvement in anti-inflammatory activity with formulations containing curcumin in combination with emu oil compared to pure curcumin. These encouraging results demonstrate the potential of formulations containing curcumin and emu oil combination in rheumatoid arthritis.


Assuntos
Anti-Inflamatórios/administração & dosagem , Curcumina/administração & dosagem , Sistemas de Liberação de Medicamentos , Óleos/química , Administração Tópica , Animais , Anti-Inflamatórios/farmacologia , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Carragenina/toxicidade , Química Farmacêutica/métodos , Curcumina/farmacologia , Modelos Animais de Doenças , Edema/tratamento farmacológico , Edema/patologia , Emulsões , Excipientes/química , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Nanopartículas , Ratos , Ratos Sprague-Dawley , Solubilidade
14.
Eur J Drug Metab Pharmacokinet ; 41(5): 517-26, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26156887

RESUMO

BACKGROUND: Valsartan exhibits poor aqueous solubility and dissolution rate limited absorption. The lower solubility in the upper part of gastrointestinal tract (pH-dependant solubility) where its absorption window exists further contributes to the low oral bioavailability of valsartan. OBJECTIVE: The present work was aimed to improve the in vivo pharmacokinetics of valsartan by preparing amorphous polymeric dispersions using Eudragit E 100 as carrier. Eudragit E 100 is a cationic polymer soluble in gastric fluid up to pH 5.0 and exhibits pH-dependent release. Hence, the dispersions prepared using Eudragit E 100 rapidly dissolves at lower pH presenting drug in molecularly dispersed and soluble form at its absorption site. METHODS: Polymeric solid dispersions were prepared in different drug-to-carrier ratios. The prepared dispersions were evaluated for drug-carrier interactions, solid-state transitions and drug-release properties with the help of Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and in vitro dissolution studies. The optimized formulation containing valsartan was tested in rats for bioavailability and pharmacokinetic parameters and compared with that of valsartan pure drug. RESULTS: The results from FTIR studies indicated no interactions between drug and excipients. DSC studies confirmed reduction in crystallinity of drug. The dissolution studies performed in 0.1 N HCl showed significant improvement (p < 0.05) in the dissolution of valsartan. In vivo pharmacokinetic studies showed 199 % relative bioavailability with significant improvement (p < 0.05) in area under the curve compared to valsartan pure drug. CONCLUSION: Eudragit E 100 can be used to improve the dissolution of drugs that show low solubility at lower pH and thereby enhancing the bioavailability.


Assuntos
Polímeros/química , Valsartana/química , Valsartana/farmacocinética , Acrilatos/química , Administração Oral , Animais , Disponibilidade Biológica , Varredura Diferencial de Calorimetria/métodos , Química Farmacêutica/métodos , Portadores de Fármacos/química , Excipientes/química , Concentração de Íons de Hidrogênio , Masculino , Ratos , Ratos Wistar , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
15.
J Liposome Res ; 25(4): 325-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25776099

RESUMO

CONTEXT: The physicochemical properties of drugs such as partition coefficient play a major role in the development of lipid-based drug delivery systems. The major obstacle lies in encapsulation of a drug with low partition coefficient into these systems. OBJECTIVE: The objective of this study was to design and optimize a novel lipid-based delivery system with higher loading, improved pharmacokinetics consequently enhancing the oral bioavailability of drugs with low partition coefficient like valsartan. MATERIALS AND METHODS: The optimized formulation consists of Capryol 90, Cremophor RH 40, and Transcutol HP. Pseudo ternary phase diagrams were used to optimize the components and their concentrations in the formulation. Dissolution studies of the selected formulations were compared with plain drug and marketed product at three pH conditions (pH 1.2, 4.5 and 6.8). Pharmacokinetic parameters of optimized formulations were determined in Wistar rats and compared with that of plain drug. RESULTS AND DISCUSSION: The optimized formulation with a mean particle size of 50 nm showed significant improvement (p < 0.05) in dissolution rate with pH independence compared to plain drug and marketed product. The in vivo studies in Wistar rats revealed about 2.30- and 1.68-fold increase in the oral bioavailability and Cmax of valsartan from lipid-based formulation compared to plain drug. CONCLUSION: The engineered formulation strategy by type IV lipid-based formulations can be successfully exploited to improve the dissolution rate and oral deliverability of drugs like valsartan.


Assuntos
Glicoesfingolipídeos Acídicos/química , Portadores de Fármacos/química , Etilenoglicóis/química , Polietilenoglicóis/química , Polímeros/química , Propilenoglicóis/química , Valsartana/administração & dosagem , Valsartana/química , Administração Oral , Animais , Disponibilidade Biológica , Portadores de Fármacos/síntese química , Concentração de Íons de Hidrogênio , Masculino , Tamanho da Partícula , Ratos , Ratos Wistar , Propriedades de Superfície , Valsartana/sangue , Valsartana/farmacocinética
16.
J Microencapsul ; 32(1): 54-60, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25090596

RESUMO

The objective of the present study was to improve solubility, dissolution rate and therapeutic efficacy of a BCS Class II drug, glibenclamide by using oral self nano emulsifying powder. The powder was prepared by adsorbing the mixture of oil, surfactant and co-surfactant onto a carrier with large surface area; Aerosil 200. The ratios of oil and Smix (surfactant/co-surfactant mixture) required to produce an emulsion was optimized based on percentage transmittance studies and particle size determinations. The optimized formulation was subjected to in vitro dissolution study and in vivo therapeutic efficacy in rabbits by monitoring blood glucose levels. Scanning electron microscopy, differential scanning calorimetry and X-ray powder diffraction studies revealed that the drug was present in amorphous form in the final formulation. The in vivo study in rabbits indicated the improved therapeutic efficacy of glibenclamide in self-nanoemulsifying powder compared to plain drug.


Assuntos
Glibureto , Hipoglicemiantes , Nanopartículas/química , Administração Oral , Animais , Glicemia/metabolismo , Emulsões , Glibureto/química , Glibureto/farmacocinética , Glibureto/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/farmacologia , Pós , Coelhos
17.
Drug Dev Ind Pharm ; 41(6): 888-97, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24796274

RESUMO

Solid dispersion (SD) technique is a promising strategy to improve the solubility and dissolution of BCS class II drugs. However, only few products are marketed till today based on SD technology due to poor flow properties and stability. The present work was intended to solve these problems by using combination approach, melt dispersion and surface adsorption technologies. The main aim of the present work is to improve the absorption in the stomach (at lower pH) where the absorption window exists for the drug by improving the dissolution, resulting in the enhancement of oral bioavailability of poorly soluble, weakly acidic drug with pH dependant solubility, i.e. valsartan. Melt dispersion granules were prepared in different ratios using different carriers (Gelucire 50/13, PEG 8000 and Pluronic F-68) and lactose as an adsorbent. Similarly, physical mixtures were also prepared at corresponding ratios. The prepared dispersion granules and physical mixtures were characterized by FTIR, DSC and in vitro dissolution studies. DSC studies revealed reduction in the crystallinity with a possibility of presence of amorphous character of drug in the dispersion granules. From dissolution studies, valsartan Gelucire dispersion (GSD4; 1:4 ratio) showed complete drug release in 30 min against the plain drug which showed only 11.31% of drug release in 30 min. Pharmacokinetic studies of optimized formulation in male Wistar rats showed 2.65-fold higher bioavailability and 1.47-fold higher Cmax compared to pure drug. The melt dispersion technology has the potential to improve dissolution and the bioavailability of BCS class II drugs.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Valsartana/administração & dosagem , Administração Oral , Bloqueadores do Receptor Tipo 1 de Angiotensina II/química , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacocinética , Animais , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Química Farmacêutica/métodos , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Masculino , Ratos , Ratos Wistar , Solubilidade , Valsartana/química , Valsartana/farmacocinética
18.
J Drug Deliv ; 2014: 692793, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25371826

RESUMO

The objective of the present work was to obtain pH independent and improved dissolution profile for a poorly soluble drug, telmisartan using liquisolid compacts. Liquisolid compacts were prepared using Transcutol HP as vehicle, Avicel PH102 as carrier, and Aerosil 200 as a coating material. The formulations were evaluated for drug excipient interactions, change in crystallinity of drug, flow properties, and general quality control tests of tablets using Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD), angle of repose, and various pharmacopoeial tests. In vitro dissolution studies were performed at three pH conditions (1.2, 4.5 and 7.4). Stability studies were performed at 40°C and 75% RH for three months. The formulation was found to comply with Indian pharmacopoeial limits for tablets. FTIR studies confirmed no interaction between drug and excipients. XRD and DSC studies indicate change/reduction in crystallinity of drug. Dissolution media were selected based on the solubility studies. The optimized formulation showed pH independent release profile with significant improvement (P < 0.005) in dissolution compared to plain drug and conventional marketed formulation. No significant difference was seen in the tablet properties, and drug release profile after storage for 3 months.

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