Indinavir-loaded pH-sensitive microparticles for taste masking: toward extemporaneous pediatric anti-HIV/AIDS liquid formulations with improved patient compliance

Cyclodextrin-Coordinated Liposome-in-Gel for Transcutaneous Quercetin Delivery for Psoriasis Treatment

Psoriasis is a chronic inflammatory skin disease that is difficult to treat. Quercetin (QT) is a dietary flavonoid known for its anti-inflammatory effects and safe use in humans. However, the topical application of quercetin for psoriasis treatment presents a significant challenge due to its poor water solubility and low stability in semisolid preparations, where it tends to recrystallize. This work presents a novel liposome-in-gel formulation for the quercetin-based topical treatment of psoriasis. The quercetin-loading liposomes are stabilized by hydroxypropyl-β-cyclodextrin (HPCD), which interacts with phospholipids via hydrogen bonding to form a layer of an HPCD coating on the liposome interface, thus resulting in improved stability. Various analytical techniques, such as FTIR spectroscopy, Raman spectroscopy, and TEM, were used to characterize the molecular coordination patterns between cyclodextrin and liposomes. The results demonstrated that HPCD assisted the liposomes in interfacing with the matrix lipids and keratins of the stratum corneum, thereby enhancing skin permeability and promoting drug penetration and retention in the skin. The in vivo results showed that the topical QT HPCD-liposome-in-gel improved the treatment efficacy of psoriatic plaque compared to free QT. It alleviated the symptoms of skin thickening and downregulated proinflammatory cytokines, including TNF-α, IL-17A, and IL-1β. The results suggested that the HPCD-coordinated liposome-in-gel system could be a stable carrier for topical QT therapy with good potential in psoriasis treatment.

Microfluidic Particle Engineering of Hydrophobic Drug with Eudragit E100─Bridging the Amorphous and Crystalline Gap

Co-processing active pharmaceutical ingredients (APIs) with excipients is a promising particle engineering technique to improve the API physical properties, which can lead to more robust downstream drug product manufacturing and improved drug product attributes. Excipients provide control over critical API attributes like particle size and solid-state outcomes. Eudragit E100 is a widely used polymeric excipient to modulate drug release. Being cationic, it is primarily employed as a precipitation inhibitor to stabilize amorphous solid dispersions. In this work, we demonstrate how co-processing of E100 with naproxen (NPX) (a model hydrophobic API) into monodisperse emulsions via droplet microfluidics followed by solidification via solvent evaporation allows the facile fabrication of compact, monodisperse, and spherical particles with an expanded range of solid-state outcomes spanning from amorphous to crystalline forms. Low E100 concentrations (≤26% w/w) yield crystalline microparticles with a stable NPX polymorph distributed uniformly across the matrix at a high drug loading (∼89% w/w). Structurally, E100 incorporation reduces the size of primary particles comprising the co-processed microparticles in comparison to neat API microparticles made using the same technique and the as-received API powder. This reduction in primary particle size translates into an increased internal porosity of the co-processed microparticles, with specific surface area and pore volume ∼9 times higher than the neat API microparticles. These E100-enabled structural modifications result in faster drug release in acidic media compared to neat API microparticles. Additionally, E100-NPX microparticles have a significantly improved flowability compared to neat API microparticles and as-received API powder. Overall, this study demonstrates a facile microfluidics-based co-processing method that broadly expands the range of solid-state outcomes obtainable with E100 as an excipient, with multiscale control over the key attributes and performance of hydrophobic API-laden microparticles.

Mesoporous Silica Carrier-Based Composites for Taste-Masking of Bitter Drug: Fabrication and Palatability Evaluation

Palatability is one of the most critical characteristics of oral preparations. Therefore, the exploration of new techniques to mask the aversive taste of drugs is in continuous demand. In this study, we fabricated and characterized composites based on mesoporous silica (MPS) that consisted of MPS, a bitter drug, and release regulators. We conducted a palatability evaluation to assess the taste-masking efficacy of the composites. The composites were prepared using the dry impregnation method combined with hot-melt extrusion. Morphology and components distribution in composites were characterized by scanning electron microscopy, confocal laser scanning microscopy, X-ray photoelectron spectroscopy, powder flow properties evaluation, and nitrogen-sorption measurement. The results demonstrated that drugs mainly existed in the inner pore of composites, and release regulators existed in the inner pore and covered the composites' surface. Interactions among the composite components were studied using powder X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopy. The drug loaded into the composites was amorphous, and an intermolecular interaction occurred between the drug and the MPS. Taste-masked composites significantly reduced drug release levels under mouth conditions; thus, they prevented the interaction of the dissolved drug with taste receptors and improved palatability. An electronic tongue evaluation and a human taste panel assessment confirmed the better palatability of taste-masked composites. Moreover, the desired drug release behavior can be adjusted by choosing an appropriate release regulator, with stronger hydrophobicity of release regulators resulting in slower drug release. This work has provided new insights into taste-masking strategies for drugs with unpleasant tastes.

Development of stable amorphous solid dispersion and quantification of crystalline fraction of lopinavir by spectroscopic-chemometric methods

This study aimed to improve the dissolution of the poorly soluble drug lopinavir (LPV) by preparing amorphous solid dispersions (ASDs) using solvent evaporation method. The ASD formulations were prepared with ternary mixtures of LPV, Eudragit® E100, and microcrystalline cellulose (MCC) at various weight ratios. The ASDs were subjected to solid-state characterization and in vitro drug dissolution testing. Chemometric models based on near infrared spectroscopy (NIR) and NIR-hyperspectroscopy (NIR-H) data were developed using the partial least squares (PLS) regression and externally validated to estimate the percent of the crystalline LPV in the ASD. Initially, the solid-state characterization data of ASDs showed transformation of the drug from crystalline to amorphous. Negligible fraction of crystalline LPV was present in the ASD (3%). Compared to pure LPV, ASDs showed faster and higher drug dissolution (<2% vs. 60.3-73.5%) in the first 15 min of testing. The ASD was stable against crystallization during stability testing at 40 °C/75% for a month. In conclusion, the prepared ASD was stable against devitrification and enhance the dissolution of LPV.

Development and Evaluation of Cocoa Butter Taste Masked Ibuprofen Using Supercritical Carbon Dioxide

Masking the unpleasant taste of the pharmaceutically active ingredients plays a critical role in patient acceptance, particularly for children. This work's primary objective was the preparation of taste-masked ibuprofen microparticles using cocoa butter with the assistance of supercritical fluid technology. Microparticles were prepared by dissolving ibuprofen in melted cocoa butter at 40 °C. The solution was then introduced into a supercritical fluid unit and processed at 10 MPa CO₂ pressure for 30 min. The product was collected after depressurizing the system. The effect of the drug to cocoa butter ratio and the supercritical fluid units' configuration on product quality was evaluated and compared with the sample prepared by a conventional method. Physicochemical characterization of the prepared product, including particle size, crystallinity, entrapment efficiency, in vitro drug release, and product taste using a human volunteer panel was conducted. The produced microparticles were in the range of 1.42 to 15.28 μm. The entrapment efficiency of the formulated microparticles ranged from 66 to 81%. The drug:polymer ratio, the configuration of the supercritical fluid unit, and the method of preparation were found to have a critical role in the formulation of ibuprofen microparticles. Taste evaluation using human volunteers showed that microparticles containing 20% drug and processed with supercritical fluid technology were capable of masking the bitter taste of ibuprofen. In conclusion, the dispersion of ibuprofen in cocoa butter using supercritical fluid technology is a a promising innovative method to mask the bitter taste of ibuprofen.

Monoolein-based nanoparticles containing indinavir: a taste-masked drug delivery system

OBJECTIVE

This study developed a novel child-friendly drug delivery system for pediatric HIV treatment: a liquid, taste-masked, and solvent-free monoolein-based nanoparticles formulation containing indinavir (0.1%).

SIGNIFICANCE

Adherence to antiretroviral therapy by pediatric patients is difficult because of the lack of dosage forms adequate for children.

METHODS

Monoolein-based nanoparticles were developed. The particle size, zeta potential, pH, drug content, small angle X-ray scattering, stability, in vitro drug release profile, biocompatibility, toxicity, and taste-masking properties were evaluated.

RESULTS

Monoolein-based formulations containing indinavir had nanosized particles with 155 ± 7 nm, unimodal particle size distribution, and polydispersity index of 0.16 ± 0.03. The zeta potential was negative (-31.3 ± 0.3 mV) and pH was neutral (7.78 ± 0.01). A 96% drug incorporation efficiency was achieved, and the indinavir concentration remained constant for 30 days. Polarized light microscopy revealed isotropic characteristics. Transmission electron microscopy images showed spherical shaped morphology. Small-angle X-ray scattering displayed a form factor broad peak. Indinavir had a sustained release from the nanoparticles. The system was nonirritant and was able to mask drug bitter taste.

CONCLUSIONS

Monoolein-based nanoparticles represent a suitable therapeutic strategy for antiretroviral treatment with the potential to reduce the frequency of drug administration and promote pediatric adherence.

Tablet Scoring: Current Practice, Fundamentals, and Knowledge Gaps

Oral solid dosage formulations and/or tablets have remained the preferred route of administration by both patients and health care practitioners. Oral tablets are easy to administer, they are non-invasive and cause less risk adversity. Because of the lack of commercially available tablet dose options, tablets are being split or partitioned by users. Tablet scoring refers to the breakage of a tablet to attain a desired efficacy dose and is an emerging concept in the pharmaceutical industry. The primary reason for the tablet scoring practice is to adjust the dose: dose tapering or dose titrating. Other reasons for tablet partitioning are to facilitate dose administration, particularly among the pediatric and the geriatric patient population, and to mitigating the high cost of prescription drugs. The scope of this review is to: (1) evaluate the advantages and inconveniences associated with tablet scoring/portioning, and (2) identify factors in the formulation and the manufacturing of tablets that influence tablet splitting. Whereas tablet partitioning has been a common practice, there is a lack of understanding regarding the fundamentals underpinning the performance of tablets with respect to splitting. Several factors can influence tablet partitioning: tablet size, shape, and thickness. A requirement has recently been set by the European Pharmacopoeia and the U.S. Food and Drug Administration for the uniformity of mass of subdivided tablets. For breaking ease, an in-vivo reference test and a routinely applicable in-vitro test need to be established.

Relationship between Degree of Polymeric Ionisation and Hydrolytic Degradation of Eudragit® E Polymers under Extreme Acid Conditions

The commercial copolymers Eudragit^® E 100 and Eudragit^® PO are widely used materials in the pharmaceutical field as coating systems. Such materials derived from amino-methacrylate groups under acidulated conditions may acquire an ionisable fraction or undergo hydrolytic degradation of the polymeric structure. This work focused on establishing the chemical, physical, and surface changes of two reprocessed polymeric materials, here named as EuCl-E-100 and EuCl-E-PO, which were obtained from the commercial Eudragit^® E 100 and Eudragit^® E PO, respectively. The commercial materials were exposed to extreme acid conditions, where the polymers were solubilised and subsequently dried by the refractance window method. The materials obtained were chemically characterised by potentiometric titration, nuclear magnetic resonance spectroscopy (¹H NMR and ¹³C NMR) in one and two dimensions (COSY, HSQC, and HMBC), infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry. Changes in the physical properties of the materials were evaluated through studies of flowability, compactability, and their ability to gain and lose humidity. Surface thermodynamic studies were carried out through contact angle measurements using the sessile drop method. The results showed that the processed polymeric materials acquired a substantial degree of ionisation without undergoing hydrolysis of the esterified groups. Furthermore, such changes improved the flow characteristics of the material and the solubility in aqueous media at pH > 5, while also maintaining the hydrophobicity degree of the polymeric surface.

Pharmaceutical Approaches to HIV Treatment and Prevention

Human immunodeficiency virus (HIV) infection continues to pose a major infectious disease threat worldwide. It is characterized by the depletion of CD4+ T cells, persistent immune activation, and increased susceptibility to secondary infections. Advances in the development of antiretroviral drugs and combination antiretroviral therapy have resulted in a remarkable reduction in HIV-associated morbidity and mortality. Antiretroviral therapy (ART) leads to effective suppression of HIV replication with partial recovery of host immune system and has successfully transformed HIV infection from a fatal disease to a chronic condition. Additionally, antiretroviral drugs have shown promise for prevention in HIV pre-exposure prophylaxis and treatment as prevention. However, ART is unable to cure HIV. Other limitations include drug-drug interactions, drug resistance, cytotoxic side effects, cost, and adherence. Alternative treatment options are being investigated to overcome these challenges including discovery of new molecules with increased anti-viral activity and development of easily administrable drug formulations. In light of the difficulties associated with current HIV treatment measures, and in the continuing absence of a cure, the prevention of new infections has also arisen as a prominent goal among efforts to curtail the worldwide HIV pandemic. In this review, the authors summarize currently available anti-HIV drugs and their combinations for treatment, new molecules under clinical development and prevention methods, and discuss drug delivery formats as well as associated challenges and alternative approaches for the future.

Challenges and Opportunities in the Development of HIV Medications in Pediatric Patients

Successful management of pediatric HIV disease requires high therapeutic efficacy and adherence, which can be achieved by providing affordable, easy to store, and palatable antiretrovirals. Current challenges in pediatric antiretroviral drug development include poor palatability, large pill size, limited oral liquid formulations, and few incentives for development by drug manufacturers as the number of children with HIV continues to decline due to successful worldwide preventive interventions and improved access to antiretrovirals. This article summarizes the various challenges and opportunities with current pediatric antiretrovirals, recent and ongoing trials, new formulations, and suggestions that may expedite and provide incentives for the development of suitable pediatric formulations.

Challenges in oral drug delivery of antiretrovirals and the innovative strategies to overcome them

Development of novel drug delivery systems (DDS) represents a promising opportunity to overcome the various bottlenecks associated with the chronic antiretroviral (ARV) therapy of the human immunodeficiency virus (HIV) infection. Oral drug delivery is the most convenient and simplest route of drug administration that involves the swallowing of a pharmaceutical compound with the intention of releasing it into the gastrointestinal tract. In oral delivery, drugs can be formulated in such a way that they are protected from digestive enzymes, acids, etc. and released in different regions of the small intestine and/or the colon. Not surprisingly, with the exception of the subcutaneous enfuvirtide, all the marketed ARVs are administered orally. However, conventional (marketed) and innovative (under investigation) oral delivery systems must overcome numerous challenges, including the acidic gastric environment, and the poor aqueous solubility and physicochemical instability of many of the approved ARVs. In addition, the mucus barrier can prevent penetration and subsequent absorption of the released drug, a phenomenon that leads to lower oral bioavailability and therapeutic concentration in plasma. Moreover, the frequent administration of the cocktail (ARVs are administered at least once a day) favors treatment interruption. To improve the oral performance of ARVs, the design and development of more efficient oral drug delivery systems are called for. The present review highlights various innovative research strategies adopted to overcome the limitations of the present treatment regimens and to enhance the efficacy of the oral ARV therapy in HIV.

The Need for Pediatric Formulations to Treat Children with HIV

Over 3.2 million children worldwide are infected with HIV, but only 24% of these children receive antiretroviral therapy (ART). ART adherence among children is a crucial part of managing human-immunodeficiency virus (HIV) infection and extending the life and health of infected children. Important causes of poor adherence are formulation- and regimen-specific properties, including poor palatability, large pill burden, short dosing intervals, and the complex storage and transportation of drugs. This review aims to summarize the various regimen- and formulation-based barriers to ART adherence among children to support the need for new and innovative pediatric formulations for antiretroviral therapy (ART). Detailing the arguments both for and against investing in the development of pediatric HIV medications, as well as highlighting recent advances in pediatric ART formulation research, provides a synopsis of the current data related to pediatric ART formulations and adherence.

Mefenamic acid taste-masked oral disintegrating tablets with enhanced solubility via molecular interaction produced by hot melt extrusion technology

The objective of this study was to enhance the solubility as well as to mask the intensely bitter taste of the poorly soluble drug, Mefenamic acid (MA). The taste masking and solubility of the drug was improved by using Eudragit^® E PO in different ratios via hot melt extrusion (HME), solid dispersion technology. Differential scanning calorimetry (DSC) studies demonstrated that MA and E PO were completely miscible up to 40% drug loads. Powder X-ray diffraction analysis indicated that MA was converted to its amorphous phase in all of the formulations. Additionally, FT-IR analysis indicated hydrogen bonding between the drug and the carrier up to 25% of drug loading. SEM images indicated aggregation of MA at over 30% of drug loading. Based on the FT-IR, SEM and dissolution results for the extrudates, two optimized formulations (20% and 25% drug loads) were selected to formulate the orally disintegrating tablets (ODTs). ODTs were successfully prepared with excellent friability and rapid disintegration time in addition to having the desired taste-masking effect. All of the extruded formulations and the ODTs were found to be physically and chemically stable over a period of 6 months at 40°C/75% RH and 12 months at 25°C/60% RH, respectively.

Physicochemical stability of captopril and enalapril extemporaneous formulations for pediatric patients

The prevalence of hypertension among children has been increasing. Community and Hospital Pharmacists are often challenged to provide an oral liquid extemporaneous formulation for pediatric patients, because there are no appropriate dosage drugs to the specific needs of the child. The objective of this study is to choose and develop suitable pediatric extemporaneous formulations for captopril and enalapril maleate and to determine their physicochemical stability. A survey was carried out to evaluate the extent of dispensation of these drugs in Hospitals in Spain. Stability studies of formulations have been studied according to ICH normative at 5, 25 and 40 °C. Three samples from each temperature were withdrawn and assessed for stability on days 0, 15, 30, 50 and 90 using a high-performance liquid chromatography (HPLC) mass spectrometer assay. Rheological studies were carried out to ensure the maintenance of the physical characteristics of these non-Newtonian fluids. Captopril and enalapril maleate formulations used the pure drug and were stable during 50 days at 5 °C. We have developed easy antihypertensive oral liquid extemporaneous formulations for pediatric patients with physical and chemical stability higher than those provided by the majority of Hospitals.

Adherence to the Treatment of Children Living with HIV: A Conceptual Analysis

Objetivo: Analizar el concepto de la adherencia al tratamiento de los niños que viven con el VIH, expresado en la literatura de la salud, haciendo la identificación de sus atributos esenciales, antecedentes y consecuencias. Método: método evolutivo de análisis de concepto propuesto por Rodgers para evaluar los 17 artículos que se centraron en el tema del estudio. Resultados: identificado como atributos esenciales que caracterizan el concepto. A raíz de la prescripción por el binomio niño-familia, la disponibilidad de formulaciones pediátricas, acompañamiento clínico y de laboratorio regulares, adecuación de los hábitos y toma de decisiones compartida entre el cuidador y el niño. Conclusiones: con base en los elementos identificados, se elaboró una definición consensuada en que se entiende la adherencia al tratamiento de los niños VIH positivos como un proceso de colaboración que va más allá de tomar los medicamentos, teniendo en cuenta el dinamismo, los aspectos de la familia, la vida cotidiana de los niños, la parte social, económica y estructural del fenómeno en estudio. Los hallazgos permiten una comprensión más amplia del concepto y ofrecer subsidios para la prestación de la atención integral dirigida a controlar la enfermedad y mejorar la calidad de vida. Se sugiere la formación de grupos multidisciplinarios dedicados a la realización de trabajos educativos sobre las dificultades en el cumplimiento, la promoción de un espacio de intercambio de experiencias y el desarrollo de estrategias de afrontamiento

Novel formulation and drug delivery strategies for the treatment of pediatric poverty-related diseases

INTRODUCTION

Due to a lack of approved drugs and formulations, children represent the most vulnerable patients. Magistral, unlicensed formulations obtained by the manipulation of solid forms should undergo clinical evaluation to ensure bioequivalence. The development of new pediatric medicines is complex and faces technological, economic and ethical challenges. This phenomenon has contributed to the emergence of an adult-children gap. To improve the situation, the World Health Organization launched the global campaign 'Make medicines child size' and a number of international initiatives have been established. The situation is more critical in the case of poverty-related diseases (PRDs) that mainly affect poor countries.

AREAS COVERED

This review critically discusses different strategies to develop pediatric formulations and drug delivery systems (DDS) in PRDs and their potential implementation in the current market. Readers will gain an updated perspective on the development of pediatric medicines for the treatment of PRDs and the proximate challenges and opportunities faced to ensure an effective pharmacotherapy.

EXPERT OPINION

There is an urgent need for the development of innovative, scalable and cost-viable formulations to ensure pediatric patients have access to appropriate medications for PRDs. The guidelines of the International Conference on Harmonisation constitute a very good orientation tool, as they emphasize physiological and developmental aspects that need to be considered in pediatric research. It is important to consider cultural, economic and ethical aspects that make developing nations facing PRDs different from the developed world. Thus, the best strategy would probably be to conceive and engage similar initiatives in the developing world, to address unattended therapeutic niches.

A novel impinging aerosols method for production of propranolol hydrochloride-loaded alginate gel microspheres for oral delivery

Propranolol hydrochloride was directly encapsulated in alginate gel microspheres (40-50 µm in diameter) using a novel method involving impinging aerosols of CaCl(2) cross-linking solution and sodium alginate solution containing the drug. Microspheres formulated using 0.1 M CaCl(2) exhibited the highest drug loading (14%, w/w of dry microspheres) with 66.5% encapsulation efficiency. Less than 4% and 35% propranolol release occurred from hydrated and dried microspheres, respectively, in 2 h in simulated gastric fluid (SGF). The majority of the drug load (90%) was released in 5 and 7 h from hydrated and dried microspheres, respectively, in simulated intestinal fluid (SIF). Prior incubation of hydrated microspheres (cross-linked using 0.5 M CaCl(2)) in SGF prolonged the time of release in SIF to 10 h, which has implications for the design of protocols and correlation with in vivo release behaviour. Restricted propranolol release in SGF and complete extraction in SIF demonstrate the potential of alginate gel microspheres for oral delivery of pharmaceuticals.

Interventions to improve adherence to antiretroviral therapy in children with HIV infection

BACKGROUND

Achieving and maintaining high levels of medication adherence are required to achieve the full benefits of antiretroviral therapy (ART), yet suboptimal adherence among children is common in both developed and developing countries.

OBJECTIVES

To conduct a systematic review of the literature of evaluations of interventions for improving paediatric ART adherence.

SEARCH METHODS

We created a comprehensive search strategy in order to identify all studies relevant to this topic. In July 2010, we searched the following electronic databases: EMBASE, MEDLINE, PsycINFO, Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL, LILACS, Web of Science, Web of Social Science, NLM Gateway (supplemented by a manual search of the most recent abstracts not included in the Gateway database). We searched abstracts from the International AIDS Conference from 2002 to 2010, the International AIDS Society Conference on Pathogenesis, Treatment and Prevention from 2003 to 2009, and from the Conference on Retroviruses and Opportunistic Infections from 1997 to 2010. We used search strategies determined by the Cochrane Review Group on HIV/AIDS. We also contacted researchers who work in this field and checked reference lists of related systematic reviews and of all included studies.

SELECTION CRITERIA

Randomised and non-randomised controlled trials of interventions to improve adherence to ART among children and adolescents (age ≤18 years) were included. Studies had to report adherence to ART as an outcome.

DATA COLLECTION AND ANALYSIS

After one author performed an initial screening to exclude citations that did not meet the inclusion criteria, two authors did a second screening of those citations that likely met the criteria. For all articles that passed the second screening, full articles were pulled in order to make a final determination. Two authors then extracted data and graded methodological quality independently. Differences were resolved through discussion.

MAIN RESULTS

Four studies met the inclusion criteria. No single intervention was evaluated by more than one trial. Two studies were conducted in low-income countries. Two studies were randomised controlled trials (RCT), and two were non-randomised trials. An RCT of a home-based nursing programme showed a positive effect of the intervention on knowledge and medication refills (p=.002), but no effect on CD4 count and viral load. A second RCT of caregiver medication diaries showed that the intervention group had fewer participants reporting no missed doses compared to the control group (85% vs. 92%, respectively), although this difference was not statistically significant (p=.08). The intervention had no effect on CD4 percentage or viral load. A non-randomised trial of peer support group therapy for adolescents demonstrated no change in self-reported adherence, yet the percentage of participants with suppressed viral load increased from 30% to 80% (p=.06). The second non-randomised trial found that the percentage of children achieving >80% adherence was no different between children on a lopinavir-ritonavir (LPV/r) regimen compared to children on a non-nucleoside reverse transcriptase regimen (p=.781). However, the proportion of children achieving virological suppression was significantly greater for children on the LPV/r regimen than for children on the NNRTI-containing regimen (p=.002).

AUTHORS' CONCLUSIONS

A home-based nursing intervention has the potential to improve ART adherence, but more evidence is needed. Medication diaries do not appear to have an effect on adherence or disease outcomes. Two interventions, an LPV/r-containing regimen and peer support therapy for adolescents, did not demonstrate improvements in adherence, yet demonstrated greater viral load suppression compared to control groups, suggesting a different mechanism for improved health outcomes. Well-designed evaluations of interventions to improve paediatric adherence to ART are needed.

Synergistic encapsulation of the anti-HIV agent efavirenz within mixed poloxamine/poloxamer polymeric micelles

This study investigated the synergistic performance of mixed polymeric micelles made of linear and branched poly(ethylene oxide)-poly(propylene oxide) for the more effective encapsulation of the anti-HIV drug efavirenz. The co-micellization process of 10% binary systems combining different weight ratios of a highly hydrophilic poloxamer (Pluronic F127) and a more hydrophobic poloxamine counterpart (Tetronic T304 and T904) was investigated by means of dynamic light scattering, cloud point and electronic spin resonance experiments. Then, the synergistic solubilization capacity of the micelles was shown. Findings revealed a sharp solubility increase from 4 μg/ml up to more than 33 mg/ml, representing a 8430-fold increase. Moreover, the drug-loaded mixed micelles displayed increased physical stability over time in comparison with pure poloxamine ones. Overall findings confirmed the enormous versatility of the poloxamer/poloxamine systems as Trojan nanocarriers for drug encapsulation and release by the oral route and they entail a relevant enhancement of the previous art towards a more compliant pediatric HIV pharmacotherapy.

Formulation of dacarbazine-loaded cubosomes. Part III. Physicochemical characterization

The purpose of this study was to investigate the physicochemical properties of dacarbazine-loaded cubosomes. The drug-loaded cubosome nanocarriers were prepared by a fragmentation method and then freeze dried. They were then characterized for size, morphology, thermal behavior, and crystallography using dynamic light scattering, transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD), respectively. The drug loading and encapsulation efficiency were determined by UV spectrophotometry. The results showed that the prepared dacarbazine-loaded cubosomes had mean diameters ranging from 86 to 106 nm. In addition to the TEM, the characteristic peaks from PXRD data suggested that the freeze-dried nanoformulations were indeed cubic in nature. DSC and PXRD analysis suggested the 0.06 or 0.28% w/w actual drug loaded inside cubosomes was in the amorphous or molecular state. These physicochemical characteristics would affect the nanoformulation shelf-life, efficacy, and safety.

Pure drug and polymer based nanotechnologies for the improved solubility, stability, bioavailability and targeting of anti-HIV drugs

The impact of human immunodeficiency virus (HIV) infection has been devastating with nearly 7400 new infections every day. Although, the advent of highly active antiretroviral therapy (HAART) has made a tremendous contribution in reducing the morbidity and mortality in developed countries, the situation in developing countries is still grim with millions of people being infected by this disease. The new advancements in the field of nanotechnology based drug delivery systems hold promise to improve the situation. These nanoscale systems have been successfully employed in other diseases such as cancer, and therefore, we now have a better understanding of the practicalities and technicalities associated with their clinical development. Nanotechnology based approaches offer some unique opportunities specifically for the improvement of water solubility, stability, bioavailability and targeting of antiretroviral drugs. This review presents discussion on the contribution of pure drug and polymer based nanotechnologies for the delivery anti-HIV drugs.

Recent developments in liposomes, microparticles and nanoparticles for protein and peptide drug delivery

Proteins and peptides are increasingly recognized as potential leads for the development of new therapeutics for a variety of human ailments. Due to their relatively specific mode of action, proteins and peptides can be administered at relatively low doses for therapeutic effects. As natural biological products, these low doses reduce the risk otherwise caused by other small molecular drugs or larger charged molecules. Unfortunately, their therapeutic potential and clinical application is frequently hampered by various obstacles to their successful delivery. This review discusses the recent developments in the fields of liposome, microparticle and nanoparticle pertinent to protein and peptide delivery covering those systems tested and/or validated in vivo.

Efavirenz-loaded polymeric micelles for pediatric anti-HIV pharmacotherapy with significantly higher oral bioavailability

Children constitute the most challenging population in anti-HIV/AIDS pharmacotherapy. Efavirenz (EFV; aqueous solubility 4 µg/ml, bioavailability 40–45%) is a first-line agent in the pediatric therapeutic cocktail. The liquid formulation of EFV is not available worldwide, preventing appropriate dose adjustment and more convenient administration. The bioavailability of liquid EFV is lower than that of the solid formulation. Improving the bioavailability of the drug would reduce the cost of treatment and enable less affluent patients to access this drug. Aim: To encapsulate EFV in polymeric micelles to improve the aqueous solubility and the the oral bioavailability of the drug. Methods: EFV was incorporated into the core of linear and branched poly(ethylene oxide)–poly(propylene oxide) block copolymer micelles. The size and size distribution of the drug-loaded aggregates were characterized by dynamic light scattering and the morphology by transmission electron microscopy. The bioavailability of the EFV-loaded micellar system (20 mg/ml) was assessed in male Wistar rats (40 mg/kg) and compared to that of a suspension prepared with the content of EFV capsules in 1.5% carboxymethylcellulose PBS solution (pH 5.0), and an EFV solution in a medium-chain triglyceride (Miglyol® 812). Results: This work demonstrates that the encapsulation of EFV, which is poorly water soluble, into polymeric micelles of different poly(ethylene oxide)–poly(propylene oxide) block copolymers significantly improves the oral bioavailability of the drug, and reduces the interindividual variability. Conclusion: This strategy appears a very promising one towards the development of a liquid aqueous EFV formulation for the improved pediatric HIV pharmacotherapy.