Kanamycin Sulphate Loaded PLGA-Vitamin-E-TPGS Long Circulating Nanoparticles Using Combined Coating of PEG and Water-Soluble Chitosan.

Kanamycin sulphate (KS) is a Mycobacterium tuberculosis protein synthesis inhibitor. Due to its intense hydrophilicity, KS is cleared from the body within 8 h. KS has a very short plasma half-life (2.5 h). KS is used in high concentrations to reach the therapeutic levels in plasma, which results in serious nephrotoxicity/ototoxicity. To overcome aforementioned limitations, the current study aimed to develop KS loaded PLGA-Vitamin-E-TPGS nanoparticles (KS-PLGA-TPGS NPs), to act as an efficient carrier for controlled delivery of KS. To achieve a substantial extension in blood circulation, a combined design, affixation of polyethylene glycol (PEG) to KS-PLGA-TPGS NPs and adsorption of water-soluble chitosan (WSC) (cationic deacetylated chitin) to particle surface, was raised for surface modification of NPs. Surface modified NPs (KS-PEG-WSC NPs) were prepared to provide controlled delivery and circulate in the bloodstream for an extended period of time, thus minimizing dosing frequency. In vivo pharmacokinetics and in vivo biodistribution following intramuscular administration were investigated. NPs surface charge was close to neutral +3.61 mV and significantly affected by the WSC coating. KS-PEG-WSC NPs presented striking prolongation in blood circulation, reduced protein binding, and long drew-out the blood circulation half-life with resultant reduced kidney sequestration vis-à-vis KS-PLGA-TPGS NPs. The studies, therefore, indicate the successful formulation development of KS-PEG-WSC NPs with reduced frequency of dosing of KS indicating low incidence of nephrotoxicity/ototoxicity.

Effect of PEG and water-soluble chitosan coating on moxifloxacin-loaded PLGA long-circulating nanoparticles.

Moxifloxacin (MOX) is a Mycobacterium tuberculosis DNA gyrase inhibitor. Due to its intense hydrophilicity, MOX is cleared from the body within 24 h and required for repetitive doses which may then result in hepatotoxicity and acquisition of MOX resistant-TB, related with its use. To overcome the aforementioned limitations, the current study aimed to develop PLGA nanoparticles (PLGA NPs), to act as an efficient carrier for controlled delivery of MOX. To achieve a substantial extension in blood circulation, a combined design, affixation of polyethylene glycol (PEG) to MOX-PLGA NPs and adsorption of water-soluble chitosan (WSC) (cationic deacetylated chitin) to particle surface, was rose for surface modification of NPs. Surface modified NPs (MOX-PEG-WSC NPs) were prepared to provide controlled delivery and circulate in the bloodstream for an extended period of time, thus minimizing dosing frequency. In vivo pharmacokinetic and in vivo biodistribution following oral administration were investigated. NP surface charge was closed to neutral +4.76 mV and significantly affected by the WSC coating. MOX-PEG-WSC NPs presented striking prolongation in blood circulation, reduced protein binding, and long-drawn-out the blood circulation half-life with resultant reduced liver sequestration vis-à-vis MOX-PLGA NPs. The studies, therefore, indicate the successful formulation development of MOX-PEG-WSC NPs that showed sustained release behavior from nanoparticles which indicates low frequency of dosing.

Comparative study of kanamycin sulphate microparticles and nanoparticles for intramuscular administration: preparation in vitro release and preliminary in vivo evaluation.

Kanamycin sulphate (KS) is a Mycobacterium tuberculosis protein synthesis inhibitor. KS is polycationic, a property responsible for KS poor oral absorption half-life (2.5 h) and rapid renal clearance, which results in serious nephrotoxicity/ototoxicity. The current study aimed to develop KS-loaded PLGA vitamin-E-TPGS microparticles (MPs) and nanoparticles (NPs) to reduce the dosing frequency and dose-related adverse effect. In vitro release was sustained up to 10 days for KS PLGA-TPGS MPs and 13 days for KS PLGA-TPGS NPs in phosphate-buffered saline (PBS) pH 7.4. The in vivo pharmacokinetic test in Wistar rats showed that the AUC0-∞ of KS PLGA-TPGS NPs (280.58 µg/mL*min) was about 1.62-fold higher than that of KS PLGA-TPGS MPs (172.30 µg/mL*min). Further, in vivo protein-binding assay ascribed 1.20-fold increase in the uptake of KS PLGA-TPGS NPs through the alveolar macrophage (AM). The studies, therefore, could provide another useful tool for successful development of KS MPs and NPs.

In vitro and in vivo performance of supersaturable self-nanoemulsifying system of trans-resveratrol.

To develop an optimized supersaturable self-nanoemulsifying drug delivery system (S-SNEDDS) in order to improve the oral bioavailability of trans-resveratrol (t-RVT), together with surmounting poor aqueous solubility, enterohepatic recirculation and controlling drug precipitation, by employing a precipitation inhibitor (PPI) that is, hydroxypropyl methylcellulose (HPMC). The long-term stability of a previously reported formulation optimized long chain triglycerides (OPT LCT-SNEDDS), consisting of Lauroglycol FCC and Transcutol P, indicated rapid precipitation of trans-resveratrol. Following incorporation of the selected PPI, the precipitates were differentiated using the X-ray diffraction (XRD) technique. An in vitro supersaturation test was carried out for the S-SNEDDS formulation. The S-SNEDDS formulation was appraised for pharmacokinetic and in situ perfusion studies. In vitro dilution of the S-SNEDDS formulation resulted in the formation of a nanoemulsion, followed by a slow precipitation of t-RVT in the S-SNEDDS formulation vis-à-vis SNEDDS formulated with OPT-LCT, where it undergoes rapid precipitation, yielding a low t-RVT concentration. The pharmacokinetic study indicated that the AUC(0-8h) of the S-SNEDDS formulation increased by nearly 1.33-fold in the presence of HPMC vis-à-vis the OPT LCT-SNEDDS, at a drug dose of 20 mg/kg. The in situ perfusion parameters, viz., fraction absorbed and effective permeability, demonstrated significant improvement in the rate and extent of absorption from the S-SNEDDS formulation. This case demonstrates that the supersaturatable approach is effective in delivering and in improving the oral bioavailability of t-RVT.

Atazanavir-loaded Eudragit RL 100 nanoparticles to improve oral bioavailability: optimization and in vitro/in vivo appraisal.

Atazanavir (ATV) is a HIV protease inhibitor. Due to its intense lipophilicity, the oral delivery of ATV encounters several problems such as poor aqueous solubility, pH-dependent dissolution, rapid first-pass metabolism in liver by CYP3A5, which result in low bioavailability. To overcome afore mentioned limitations, ATV-loaded Eudragit RL100 nanoparticles (ATV NPs) were prepared to enhance oral bioavailability. ATV NPs were prepared by nanoprecipitation method. The ATV NPs were systematically optimized (OPT) using 3(2) central composite design (CCD) and the OPT formulation located using overlay plot. The pharmacokinetic study of OPT formulation was investigated in male Wistar rats, and in-vitro/in-vivo correlation level was established. Intestinal permeability of OPT formulation was determined using in situ single pass perfusion (SPIP) technique. Transmission electron microscopy studies on OPT formulation demonstrated uniform shape and size of particles. Augmentation in the values of Ka (2.35-fold) and AUC0-24 (2.91-fold) indicated significant enhancement in the rate and extent of bioavailability by the OPT formulation compared to pure drug. Successful establishment of in vitro/in vivo correlation (IVIVC) Level A substantiated the judicious choice of the in vitro dissolution milieu for simulating the in vivo conditions. In situ SPIP studies ascribed the significant enhancement in absorptivity and permeability parameters of OPT formulation transport through the Peyer's patches. The studies, therefore, indicate the successful formulation development of NPs with distinctly improved bioavailability potential and can be used as drug carrier for sustained or prolonged drug release.

Nanostructured Delivery Systems: Augmenting the Delivery of Antiretroviral Drugs for Better Management of HIV/AIDS.

In the last two decades, HIV-1, the retrovirus associated with acquired immunodeficiency syndrome (AIDS), is globally one of the primary causes of morbidity and mortality. Unfortunately, existing approaches for interventions are not able to suppress the progression of infection due to this virus. Of the many obstacles, viral entry into the mono-nuclear phagocyte system encompassing monocytes/macrophages and dendritic cells is a major concern. Viral infection is also responsible for the subsequent distribution of the virus into various tissues throughout the organism. Tremendous progress has been made during the past few years to diagnose and treat patients with HIV/AIDS infection, yet much remains to be done. Recommended treatment involves long-term and multiple drug therapy that causes severe side effects. With almost 12% of the world population suffering from HIV/AIDS, better management of this global threat is highly desired. Nanostructured delivery systems hold promise for improving the situation. Such systems can facilitate the uptake of antiretroviral drugs, causing a considerable improvement in HIV/AIDS therapy. Nanoscale systems have intriguing potential to drastically improve existing HIV/AIDS diagnosis and treatment platforms. Nanosystems constitute a wide range of systems varying from polymeric nanoparticles, to solid-lipid nanoparticles, liposomes, micro- and nanoemulsions, dendrimers, and self-nanoemulsifying systems. Improved bioavailability, solubility, stability, and biocompatibility make them an ideal choice for delivery of antiretroviral drugs. The present review initially describes an updated bird's-eye view account of the literature. Then, we provide a relatively sententious overview on updated patents of recent nanostructured delivery systems for antiretroviral drugs. Finally, we discuss low-cost therapy (such as antioxidants and immune modulators) for the treatment and prevention of HIV/AIDS.

Dawn of antioxidants and immune modulators to stop HIV-progression and boost the immune system in HIV/AIDS patients: An updated comprehensive and critical review.

In the last two decades, human immunodeficiency virus (HIV), the retrovirus responsible for the acquired immunodeficiency syndrome (AIDS), is one of the leading causes of morbidity and mortality, worldwide. Providing the optimum management of HIV/AIDS is a major challenge in the 21st century. Since, HIV-infected persons have an extended lifespan due to the development of effective antiretroviral therapies, malnutrition is becoming central factors of long-term survivors. The nutrition status of AIDS patients has a significant influence on the maintenance and optimal effectiveness of the immune system. Micronutrient therapy in combination with allopathic treatments can extend and improve the quality and quantity of life in individuals infected with HIV/AIDS. HIV infection is thought to lead to augmented oxidative stress which may in turn lead to faster development of HIV disease. Hence, antioxidants might have a significant role in the treatment of HIV/AIDS. An additional approach to treating HIV infection is fortifying the immune response of infected people. Immune modulators help to activate and boost the normal immune function. The present review first describes the boon of antioxidants (especially Vitamin A) and immune modulators (cytolin, resveratrol, murabutide, setarud, tucaresol, AVR118, Immunitin (HE2000), reticulose, and interleukin-7) in the treatment of HIV/AIDS. Then, providing a comparatively succinct outline on updated patents study on antioxidants and immune modulators to treat HIV/AIDS will be discussed.

Nanocarrier-based interventions for the management of MDR/XDR-TB.

Emergence of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB over the past decade presents an unprecedented public health challenge to which countries of concern are responding far too slowly. Global Tuberculosis Report 2014 marks the 20th anniversary of the Global Project on Anti-Tuberculosis Drug Resistance Surveillance, indicating the highest global level of drug-resistance ever recorded detection of 97 000 patients with MDR-TB resulting in 170 000 deaths in 2013. Treatment of MDR-TB is expensive, complex, prolonged (18-24 months) and associated with a higher incidence of adverse events. In this context, nanocarrier delivery systems (NDSs) efficiently encapsulating considerable amounts of second-line anti tubercular drugs ((s)ATDs), eliciting controlled, sustained and more profound effect to trounce the need to administer (s)ATDs at high and frequent doses, would assist in improving patient compliance and avoid hepatotoxicity and/or nephrotoxicity/ocular toxicity/ototoxicity associated with the prevalent (s)ATDs. Besides, NDSs are also known to inhibit the P-glycoprotein efflux, reduce metabolism by gut cytochrome P-450 enzymes and circumnavigate the hepatic first-pass effect, facilitating absorption of drugs via intestinal lymphatic pathways. This review first provides a holistic account on MDR-TB and discusses the molecular basis of Mycobacterium tuberculosis resistance to anti-tubercular drugs. It also provides an updated bird's eye view on current treatment strategies and laboratory diagnostic test for MDR-TB. Furthermore, a relatively pithy view on patent studies on second-line chemotherapy using NDSs will be discussed.

Trans-resveratrol self-nano-emulsifying drug delivery system (SNEDDS) with enhanced bioavailability potential: optimization, pharmacokinetics and in situ single pass intestinal perfusion (SPIP) studies.

Trans-resveratrol (t-RVT) is a potent antioxidant. By virtue of extensive pre-systemic metabolism and existence of enterohepatic recirculation, t-RVT bioavailability is almost zero. The current study aimed to develop self-nanoemulsifying drug delivery systems (SNEDDS) using long-chain triglycerides (LCTs) of t-RVT in an attempt to circumvent such obstacles. Equilibrium solubility studies indicated the choice of Lauroglycol FCC as lipid, and of Labrasol and Transcutol P as surfactants, for formulating the SNEDDS. Ternary phase diagrams were constructed to select the areas of nanoemulsions, and the amounts of lipid (X(1)) and surfactant (X(2)) as the critical factor variables. The SNEDDS were optimized using 3(2) central composite design (CCD) and the optimized formulation (OPT) located using overlay plot. The nanometer size range and high negative values of zeta potential depicted non-coalescent nature of the SNEDDS. Optimized formulation indicated marked improvement in drug release profile vis-à-vis pure drug. Cloud point determination and accelerated stability studies ascertained the stability of OPT. Augmentation in the values of K(a) (3.29-fold) and AUC (4.31-fold) indicated significant enhancement in the rate and extent of bioavailability by the OPT compared with pure drug. In situ perfusion (SPIP) studies in Wistar rats construed remarkable enhancement in the absorptivity and permeability parameters of SNEDDS vis-à-vis the pure drug. Successful establishment of level A of in vitro/in vivo correlation substantiated the judicious choice of the in vitro dissolution milieu for simulating the in vivo conditions. The present study, therefore, reports the successful development of SNEDDS with distinctly enhanced bioavailability of t-RVT.

Recent advances of resveratrol in nanostructured based delivery systems and in the management of HIV/AIDS.

Resveratrol, a natural polyphenolic compound present in trees, in peanuts, in grapevines and exhibited multiple pharmacological activities. Extensive research in last two decades suggested that resveratrol possesses anti-inflammatory, anti-cancer, anti-viral, anti-amyloid, anti-arthritic and antioxidant properties. Some clinical reports have proposed that resveratrol might be a potential candidate for the prevention and/or treatment of HIV/AIDS and synergistically enhances the anti-HIV-1 activity. Resveratrol is not toxic to cells, and by itself reduces viral replication by 20% to 30%. With almost 12% of the world population suffering from HIV/AIDS including its resurgence in the developed world, better management of this global threat is highly desired. Further, various studies demonstrated several issues associated with resveratrol which account for its poor systemic bioavailability (almost zero) due to rapid and extensive first pass metabolism and existence of enterohepatic recirculation. In order to improve bioavailability and cellular uptake of resveratrol, various strategies have been adopted to date which includes resveratrol prodrug and the development of nanostructured delivery systems. Besides, nanostructured delivery systems are also known to inhibit the P-glycoprotein (P-gp) efflux, reduced metabolism by gut cytochrome P-450 enzymes, and circumnavigate the hepatic first-pass effect, facilitating absorption of drugs via intestinal lymphatic pathways. This review paper provides an updated bird's-eye view account on the publications and patents study on the recent novel approaches to deliver resveratrol in order to enhance oral bioavailability, overcome first pass metabolism and trounce enterohepatic recirculation to make resveratrol a therapeutically potent drug. Providing a relatively pithy overview, this paper thus presents recent advances of resveratrol for the treatment and prevention of HIV/AIDS.

Optimized self-nanoemulsifying drug delivery system of atazanavir with enhanced oral bioavailability: in vitro/in vivo characterization.

BACKGROUND: Atazanavir (ATV) is a HIV protease inhibitor. Due to its intense lipophilicity, the oral delivery of ATV encounters several problems such as poor aqueous solubility, pH-dependent dissolution and rapid first-pass metabolism in liver by CYP3A5, which result in low and erratic bioavailability. OBJECTIVE: The current study aimed to develop self-nanoemulsifying drug delivery systems (SNEDDS) using long-chain triglycerides of ATV in an attempt to circumvent such obstacles. METHODS: Equilibrium solubility studies indicated the choice of Maisine 35-1 as lipid, and of Transcutol P and Span 20 as surfactants, for formulating the SNEDDS. Ternary phase diagrams were constructed to select the areas of nanoemulsions, and the amounts of lipid (X1) and surfactant (X2) as the critical factor variables. The SNEDDS were optimized (OPT) using 3(2) central composite design and the OPT formulation located using overlay plot. The pharmacokinetics and in situ single-pass intestinal perfusion studies of OPT formulation were investigated in Wistar rats. RESULTS: OPT formulation indicated marked improvement in drug release profile vis-à-vis pure drug. Cloud point determination and accelerated stability studies ascertained the stability of OPT formulation. Augmentation in the values of Ka (1.96-fold) and AUC (2.57-fold) indicated significant enhancement in the rate and extent of bioavailability by the OPT formulation compared to pure drug. Successful establishment of in vitro/in vivo correlation Level A substantiated the judicious choice of the in vitro dissolution milieu for simulating the in vivo conditions. CONCLUSION: The studies, therefore, indicate the successful formulation development of SNEDDS with distinctly improved bioavailability of ATV.

In-vitro/in-vivo characterization of trans-resveratrol-loaded nanoparticulate drug delivery system for oral administration.

OBJECTIVES: The current studies entail successful formulation of systematically optimized (OPT) nanoparticulate drug delivery system to increase the oral bioavailability using Eudragit RL 100 of trans-resveratrol (t-RVT), and evaluate their in-vitro/in-vivo performance. METHODS: t-RVT-loaded Eudragit RL 100 nanoparticles (t-RVT NPs) were prepared by nanoprecipitation method. The nanoparticles (NPs) were systematically optimized using 3(2) central composite design and the OPT formulation located using overlay plot. The pharmacokinetic and in-vivo biodistribution of t-RVT NPs were investigated in rats, and various levels of in-vitro/in-vivo correlation (IVIVC) were established. KEY FINDINGS: The OPT formulation (mean particle size: 180 nm) indicated marked improvement in drug release profile vis-à-vis pure drug and marketed formulation (MKT). Augmentation in the values of Ka (5.64-fold) and AUC0-24 (7.25-fold) indicated significant enhancement in the rate and extent of bioavailability by the optimized trans-resveratrol-loaded Eudragit RL 100 nanoparticles (OPT-t-RVT NPs) compared with pure drug. Level A of IVIVC was successfully established. OPT-t-RVT NPs showed 4.11-fold rose in the values of t-RVT concentrations in liver. In-situ single pass intestinal perfusion studies construed remarkable enhancement in the absorptivity and permeability parameters of OPT-t-RVT NPs. CONCLUSIONS: The results, therefore, insight into the role of solubility enhancement and trounce enterohepatic recirculation for improving the oral bioavailability of t-RVT.

Optimized PLGA nanoparticle platform for orally dosed trans-resveratrol with enhanced bioavailability potential.

BACKGROUND: Trans-resveratrol (t-RVT) is a potent antioxidant. The drug suffers enterohepatic recirculation and extensive first-pass metabolism by CYP3A4 in liver, resulting in very low bioavailability (almost zero). OBJECTIVE: The current studies entail a novel formulation approach to develop systematically optimized (OPT) nanoparticles (NPs) to enhance the oral bioavailability potential using poly (dl-lactide-co-glycolide) (PLGA) of t-RVT and overcome enterohepatic recirculation. METHODS: T-RVT-loaded PLGA NPs were prepared by nanoprecipitation method. Delineating the NP regions, the amounts of polymer and emulsifier were selected as the critical factors for systematically formulating the OPT NPs employing 3(2) central composite design. The pharmacokinetics, in vivo biodistribution and in situ single-pass intestinal perfusion (SPIP) studies of OPT formulation were investigated in male Wistar rats. RESULTS: Augmentation in the values of Ka (7.17-fold) and AUC0 - ∞ (10.6-fold) indicated significant enhancement in the rate and extent of bioavailability by the OPT formulation compared to pure drug and marketed product. OPT formulation showed a 2.78-fold rise in the values of t-RVT concentrations in liver. In situ SPIP studies ascribed the significant enhancement in absorptivity and permeability parameters of OPT NPs to transport through the Peyer's patches. Successful establishment of in vitro/in vivo correlation substantiated the judicious choice of the in vitro dissolution milieu for simulating the in vivo conditions. CONCLUSION: The studies, therefore, could provide another useful tool for successful development of t-RVT NPs and an in vivo approach to designate nanoparticulate system of t-RVT with distinctly improved bioavailability and to overcome enterohepatic recirculation.

Optimization (central composite design) and validation of HPLC method for investigation of emtricitabine loaded poly(lactic-co-glycolic acid) nanoparticles: in vitro drug release and in vivo pharmacokinetic studies.

The objective of the current study is to develop nanoparticles (NPs) drug delivery system of emtricitabine solely using poly(lactic-co-glycolic acid) (PLGA) and evaluate its in vitro and in vivo release performance by systematically optimized HPLC method using Formulation by Design (FbD). NPs were evaluated for in vitro release and in vivo absorption study. The desired chromatographic separation was achieved on a Phenomenex C18 (250 mm × 4.6 mm I.D., 5 µm) column, under isocratic conditions using UV detection at 280 nm. The optimized mobile phase consisted of a mixture of 40 mM phosphate dihydrogen phosphate buffer (pH 6.8), methanol, and 2% acetonitrile in a ratio of (83 : 15 : 2, v/v/v) at a flow rate of 1 mL/min. The linear regression analysis for the calibration curves showed a good linear correlation over the concentration range 0.040-2.0 µg/mL, with retention time of 4.39 min. An average encapsulation efficiency of 74.34% was obtained for NPs. In vitro studies showed zero-order release and about 95% drug being released within 15 days in PBS (pH 7.4). In conclusion, the proposed optimized method was successfully applied for the determination of in vitro and in vivo release studies of emtricitabine NPs.

Design and optimization of novel in situ gel of mercaptopurine for sustained drug delivery

Mercaptopurine is a purine antagonist, belonging to the class of antimetabolites. Its oral absorption is erratic and variable throughout GIT, with bioavailability of 5-37% and belongs to Biopharmaceutical Classification System (BCS) class IV. The focus of the present study was to improve solubility of mercaptopurine and to release the drug uniformly throughout the GIT by formulating into a novel in situ gel tablet. By in vitro swelling studies, xanthan gum was selected as the best gelling polymer and the tablets were prepared by direct compression. Sodium chloride was used as a release modifier to improve the release of drug from the tablet. A 32 full factorial design was applied to optimize the percentage of xanthan gum and sodium chloride to get desired swelling index and release profile. Tablets were evaluated for weight variation, hardness, friability, disintegration time, drug content, in vitro swelling studies and in vitro dissolution studies. The best optimized formulation showed good swelling index and extended the release up to 12 h, where as conventional tablet released the drug within 45 min. The results indicate that mercaptopurine loaded in situ gel tablet could be effective in sustaining drug release for a prolonged period of time throughout the GIT, which can possibly improve the oral bioavailability.

Mercaptopurine é um antagonista da purina, pertencente à a classe dos antimetabólitos. A sua absorção oral é errática e variável através do TGI, com biodisponibilidade de 5-37 % e pertence à classe IV, de acordo com o Sistema de Classificação Biofarmacêutica. O foco do presente estudo foi melhorar a solubilidade da mercaptopurina e liberar o fármaco uniformemente através do TGI, por meio da nova formulação de comprimidos que se tornam gel in situ. Por meio de estudos de inchamento, a goma xantana foi selecionada como o o melhor polímero gelificante e os comprimidos foram preparados por compressão direta. O cloreto de sódio também foi usado como agente modificador de liberação para aprimorar a liberação do fármaco do comprimido. Aplicou-se planejamento fatorial 32 para otimizar a porcentagem de goma xantana e de cloreto de sódio para se alcançar o índice de inchamento e o perfil de liberação desejáveis. Os comprimidos foram avaliados quanto à variação de peso, dureza, friabilidade, tempo de desintegração, conteúdo de fármaco, estudos in vitro de inchamento e de dissolução. A formulação mais bem otimizada mostrou bom índice de inchamento e liberação prolongada acima de 12 h, em comparação com um comprimido convencional, que libera o fármaco em 45 minutos. Os resultados indicam que a 6-mercaptopurina carregada no comprimido de gelificação in situ poderia ser eficaz para a liberação controlada por período de tempo prolongado através do TGI, o que pode, possivelmente, aprimorar a biodisponibilidade oral.

Taste Masked Orally Disintegrating Pellets of Antihistaminic and Mucolytic Drug: Formulation, Characterization, and In Vivo Studies in Human.

The main aim of the present study was to evaluate the potential of orally disintegrating pellets (ODPs) as an approach for taste masking of bitter drugs, namely, Ambroxol hydrochloride (A-HCl) and Cetirizine dihydrochloride (C-DHCl). Pellets were prepared by extrusion/spheronization with Eudragit EPO, kyron T-134, Kyron T-314, mannitol, sorbitol, MCC (Avicel PH-101), sucralose, chocolate flavor, and 5% xanthum gum. The prepared pellets were characterized for percentage yield, drug content, particle size, in vitro drug release, and in vivo evaluation on humans for taste, mouth feel, and in vivo disintegration time. The results revealed that the average size of pellets was influenced greatly by the percentage of binder and extrusion speed. The optimized ODPs disintegrated in less than 20 s and showed more than 98% of drugs in ODPs dissolved within 15 min. Taste perception study was carried out on human volunteers to evaluate the taste masking ability of ODPs for taste, mouth feel, and in vivo disintegration time. Crystalline state evaluation of drugs in the optimized ODPs was conducted for X-ray powder diffraction. In conclusion, the study confirmed that ODPs can be utilized as an alternative approach for effective taste masking and rapid disintegration in the oral cavity.

Pharmacokinetics and in vivo biodistribution of optimized PLGA nanoparticulate drug delivery system for controlled release of emtricitabine.

The objective of this study was to develop systematically optimized (OPT) nanoparticles (NPs) providing a controlled release using PLGA of emtricitabine (FTC) employing Formulation by Design (FbD), and evaluate their in vitro and in vivo performance. FTC generates severe adverse effects with risks of toxicity. Thus, NPs were prepared to reduce these drawbacks in this study. The NPs were prepared by water-in-oil-in-water (w/o/w) emulsion method, followed by high-pressure homogenization. The FTC NPs were systematically OPT using 3(2) central composite design and the OPT formulation located using overlay plot. The pharmacokinetics and in vivo biodistribution of OPT-FTC NPs were investigated in male Wistar rats via the oral administration. Transmission electron microscopy studies on OPT-FTC NPs demonstrated uniform shape and size of particles. In vitro release was sustained up to 15 days in PBS pH 7.4. Augmentation in the values of Cmax (1.63 fold) and AUC0-∞ (5.39 fold) indicated significant enhancement in the rate and extent of bioavailability by the OPT-FTC NPs compared to pure drug. OPT-FTC NPs showed 2.325 fold increase in the values of FTC concentrations in liver. The OPT-FTC NPs was found to be quite stable during 6 months of study period. Hence, the developed OPT-FTC NPs can be used as drug carrier for sustained/prolonged drug release and/or to reduce toxic effects.

Development and evaluation of 6-mercaptopurine and metoclopramide polypill formulation for oral administration: In-vitro and ex vivo studies.

INTRODUCTION: The present investigation was to develop a polypill of 6-mercaptopurine and metoclopramide. A polypill with delayed release granules of an anticancer and immediate release mucoadhesive tablet of antiemetic may result in the reduction of emesis caused by oral chemotherapy. MATERIALS AND METHODS: 6-Mercaptopurine granules were prepared by wet granulation process. Chitosan, hydroxypropyl methylcellulose, and ethylcellulose were used as individually as delayed release polymers. Seven granule formulations (F1-F7) were prepared and evaluated for flow properties and drug content. Immediate release mucoadhesive tablets of metoclopramide were prepared by direct compression technique using pectin and PVPK-40 as mucoadhesive polymers. Three formulations of pectin (L1-L3) and three formulations of PVPK40 (M1-M3) were prepared using lactose, magnesium stearate, and mannitol and talc as diluent and glidant, respectively. Tablets were evaluated for weight variation, hardness, friability, drug content, ex vivo mucoadhesion time, and in vitro dissolution studies. RESULTS: Formulation F2, F4, F5, and F7 showed maximum drug content. Formulation F7 exhibited the drug release up to 2 h and was selected as the best delayed release formulation. All formulations of metoclopramide showed good drug content ranging from 97.6 % to 100.6%. Formulation M2 among tablets prepared with PVP exhibited desired mucoadhesion time of 15.33 min which prolongs the duration of drug release in gastric pouch of the male Wistar rats. Both the selected formulations F7 and M2 were filled into body of capsule size 0 and capsule was evaluated for technological properties. CONCLUSION: It may be concluded that polypill released the metoclopramide immediately prior to 6-mercaptopurine.

Pharmacokinetic and pharmacodynamic evaluation of floating microspheres of metformin hydrochloride.

Metformin hydrochloride (MH), a biguanide antidiabetic, is the drug of choice in obese patients. It is well absorbed from the upper part of gastrointestinal tract and has oral bioavailability of 50% to 60%. The objective of this study was to formulate MH into floating microspheres in order to increase its residence time at the site of absorption and thus improve its bioavailability; and to extend the duration of action along with possibilities of dose reduction. Microspheres were prepared by emulsion solvent evaporation method and evaluated for particle size, entrapment efficiency, buoyancy, and in vitro release; and further characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and differential scanning calorimetry. The pharmacokinetic and pharmacodynamic evaluation of selected formulation was carried out in male Wistar diabetic rats. The data was statistically analyzed by unpaired t-test. A 3.5-fold increase in relative bioavailability was observed. The prolongation of half-life (t(1/2)) from 4.5 ± 2.41 h to 14.12 ± 4.81 h indicated extended duration of action. Oral glucose tolerance test (OGTT) was analyzed by one-way analysis of variance followed by Dunnet multiple comparison test, a significant decrease (p < 0.05) in the blood glucose levels was observed when formulations were compared with control rats. Hence, MH floating microspheres were tested at 50 mg/kg and 100 mg/kg body weight, OGTT data showed nonsignificant difference (p >0.05). In conclusion, an effective oral antidiabetics treatment can be achieved by formulating MH into floating microspheres which results in increase in bioavailability along with extended duration of action resulting in possible reduction in dose.

Optimization of pellets containing solid dispersion prepared by extrusion/spheronization using central composite design and desirability function.

Furosemide is a class IV biopharmaceutical classification system drug having poor water solubility and low bioavailability due to the hepatic first-pass metabolism and has a short half-life of 2 h. To overcome the above drawback, this study was carried to prepare and evaluate the pellets containing furosemide solid dispersion (SD) for oral administration prepared by extrusion/spheronization. SD of furosemide was prepared with Eudragit L-100 at a drug-to-polymer ratio of 1:2 by employing a solvent evaporation method and characterized. Further, microcrystalline cellulose pellets containing SD were consequently prepared using a lab scale extrusion/ spheronizer and evaluated for in vitro drug release studies. The influence of process parameters used during extrusion/spheronization on the pellet properties was also studied using 2-factor, 3-level central composite design in order to improve the product quality. Additionally, the desirability function approach was applied to acquire the preeminent compromise between the multiple responses. Pellets containing solid dispersion (PSD) were prepared using optimal parameter settings demonstrated 88.52 ± 0.69% of the drug was released in a sustained release manner till 12 h. In vitro drug release data were fitted to various release kinetics models to study the mechanism of drug release. Drug release from the PSD was found to follow zero-order and Higuchi's model. Both studied parameters had great influence on the responses. PSD showed augmentation in the drug release profile till 12 h. The final optimized formulation was obtained by encapsulating best SD formulation within the pellet core to release the drug in the most soluble form in stomach and a sustained fashion in intestine.