Pediatric drug development: formulation considerations

Spray drying Eudragit® E-PO with acetaminophen using 2- and 3-fluid nozzles for taste masking

Conventional spray drying using a 2-fluid nozzle forms matrix microparticles, where drug is distributed throughout the particle and may not effectively mask taste. In contrast, spray drying using a 3-fluid nozzle has been reported to encapsulate material. The objective of this study was to spray dry Eudragit® E-PO (EE) with acetaminophen (APAP), a water-soluble model drug with a bitter taste, using 2- and 3-fluid nozzles for taste masking. Spray drying EE with APAP, however, resulted in yields of ≤ 13 %, irrespective of nozzle configuration. Yields improved when Eudragit® L 100-55 (EL) or Methocel® E6 (HPMC) was used in the inner fluid stream of the 3-fluid nozzle or in place of EE for the 2-fluid nozzle. Drug release from microparticles prepared with the 2-fluid nozzle was relatively rapid. Using EE in the outer fluid stream of the 3-fluid nozzle resulted in comparatively slower drug release, although drug release was observed, indicating that encapsulation was incomplete. Results from these studies also show that miscible polymers used in the two fluid streams mix during the spray drying process. In addition, findings from this study indicate that the polymer used in the inner fluid stream can impact drug release.

State of the art in pediatric nanomedicines

In recent years, the continuous development of innovative nanopharmaceuticals is expanding their biomedical and clinical applications. Nanomedicines are being revolutionized to circumvent the limitations of unbound therapeutic agents as well as overcome barriers posed by biological interfaces at the cellular, organ, system, and microenvironment levels. In many ways, the use of nanoconfigured delivery systems has eased challenges associated with patient differences, and in our opinion, this forms the foundation for their potential usefulness in developing innovative medicines and diagnostics for special patient populations. Here, we present a comprehensive review of nanomedicines specifically designed and evaluated for disease management in the pediatric population. Typically, the pediatric population has distinguishing needs relative to those of adults majorly because of their constantly growing bodies and age-related physiological changes, which often need specialized drug formulation interventions to provide desirable therapeutic effects and outcomes. Besides, child-centric drug carriers have unique delivery routes, dosing flexibility, organoleptic properties (e.g., taste, flavor), and caregiver requirements that are often not met by traditional formulations and can impact adherence to therapy. Engineering pediatric medicines as nanoconfigured structures can potentially resolve these limitations stemming from traditional drug carriers because of their unique capabilities. Consequently, researchers from different specialties relentlessly and creatively investigate the usefulness of nanomedicines for pediatric disease management as extensively captured in this compilation. Some examples of nanomedicines covered include nanoparticles, liposomes, and nanomicelles for cancer; solid lipid and lipid-based nanostructured carriers for hypertension; self-nanoemulsifying lipid-based systems and niosomes for infections; and nanocapsules for asthma pharmacotherapy.

Orally disintegrating drug carriers for paediatric pharmacotherapy

Non-compliance, dosing inaccuracy, choking risk, flavour, and instability, are some of the issues associated with paediatric, oral dosage forms - tablets, capsules, solutions, and suspensions. Orally disintegrating drug carriers, a dosage form with growing interest, are thought to overcome several of the challenges associated with these conventional formulations by rapidly disintegrating within the buccal cavity without the need for water. This review serves as an up-to-date report on the various types of orodispersible delivery systems, currently being developed or commercialized, by detailing their characteristics, manufacturing processes, and applications in the paediatric population. Mentioned are orodispersible tablets, films, wafers and lyophilisates, mini-tablets, capsules, granules, electrospun fibers and webs. Also highlighted are the choice of excipients, quality control requirements, and expected pharmacokinetics of orally disintegrating drug carriers concerning the paediatric population. Overall, orodispersible formulations, particularly tablets, films, and lyophilisates/wafers, have shown to be a valuable addition to medication administration in minors, thus the execution of more targeted research and development activities is expected to lead to enhanced paediatric care and outcomes.

Successful administration of mitotane (O, p'-DDD) in pediatric oncology

INTRODUCTION

Mitotane (o, p'-DDD) is a molecule that was developed many years ago for adrenal cortical carcinoma, but no suitable pediatric dosage form is available for administration to young children. Mitotane requires therapeutic drug monitoring because of its long half-life and difficulty in stabilizing plasma concentrations. Furthermore, Mitotane is a highly lipophilic drug that requires concurrent lipid administration.

CASE REPORT

We present the case of a 3-year-old girl who was diagnosed with metastatic adrenal cortical carcinoma. Due to the difficulty in administering the tablets and the non-stabilized mitotane dosages, a nasogastric tube was inserted. An administration protocol based on dispersing the tablets in whole milk was established by the pharmacy team. This led to the stabilization of the disease for at least 1.5 years.

MANAGEMENT AND OUTCOME

Mitotanemia is difficult to stabilize even when treatment is administered orally. To maintain biological efficacy, we propose an easily reproducible protocol. The efficacy was stabilized at a dosage of 1500 mg per day. Mitotanemia fluctuated between 14 mg/mL, and 20 mg/mL. The implementation of this protocol prevented treatment discontinuation.

DISCUSSION

The administration of narrow therapeutic range drugs via a nasogastric tube is a challenge for healthcare teams, particularly in pediatric patients. Based on the findings of this clinical case, clinicians should consider future use of this protocol. The use of whole milk as a vehicle for mitotane is a simple, effective, and reproducible method to administer the drug to pediatric patients and can be used for other similar cases.

Issues on Powder Forms for Oral Solution and Suspension for Pediatric Patients in Japan: A Questionnaire-Based Observational Survey to Pediatric Pharmacists

BACKGROUND

Powders for oral solutions and suspensions (POS) are commonly used as pediatric oral medicines worldwide, except for Japan. Although global pediatric formulation development accelerates POS importation to Japan without any formulation change, oral solid multiparticulates remain to be the preferred pediatric forms in the country. This study aimed to evaluate the acceptance situation of four typical POS form products (mycophenolate mofetil, sildenafil citrate, valganciclovir hydrochloride, and voriconazole) that were recently approved in Japan.

METHODS

A questionnaire on four products was completed by pharmacists in 29 children's hospitals with more than 100 beds each, between November and December of 2019. The questionnaire has six items on (#1) type of institution, (#2) formulary status, (#3) dispensing practice, (#4) reasons why POS form(s) were not selected as hospital formulary, (#5) advantages and disadvantages of POS form, and (#6) opinions for POS form.

RESULTS

Of the 29 institutions, 7 (24%), 9 (31%), 4 (13%), and 10 (34%) institutions used POS of mycophenolate mofetil, sildenafil citrate, valganciclovir hydrochloride, and voriconazole, respectively. Reasons for not using these products were dispensed drug loss, formulation issues, and management issues in the pharmaceutical department and pediatric ward. Pharmacists preferred drug compounding such as tablet crushing and capsule opening to POS form use.

CONCLUSIONS

POS forms might be an unsuitable formulation for the current hospital settings in Japan. Thus, appropriate dosage forms that reflect the current clinical settings are necessary.

Comparative taste-masking evaluation of microencapsulated bitter drugs using Smartseal 30D and ReadyMix for paediatric dosage forms

The taste of drug substances plays a key role in the development of paediatric formulations with suitable organoleptic properties. The aim of the study was to evaluate the taste masking effectiveness of Smartseal 30D and ReadyMix on a range of bitter drug substances such as diphenhydramine HCl (DPD), ibuprofen lysine (IBU-LS), and phenylephrine HCl (PPH) for the development of paediatric dosage forms. The drugs were microencapsulated in the polymer carriers at 10-20% loadings using spray-drying processing. Spray drying of drug formulations was optimized in terms of percent yield and encapsulation efficiency followed by physicochemical characterization in order to identify the drugs' physical state in the polymer microparticles. The in vivo taste masking efficiency was evaluated using human test panel and showed noticeable reduction of drug's bitterness at all loadings in comparison to the bulk substances.

Extemporaneous Compounding and Physiological Modeling of Amlodipine/Valsartan Suspension

Method

Amlodipine/valsartan extemporaneous suspension was prepared from available commercial tablets such as Valzadepine^®. The dissolution profiles for the extemporaneous preparation and the commercial tablet were determined in different pH media. The physical, chemical, and microbial stability of the compounded formulation was evaluated over one-month period at room temperature. Moreover, in silico modeling using GastroPlus™ software was used to build absorption models for both drugs based on the in vitro dissolution data. The simulated plasma profiles for both active ingredients were compared with the in vivo plasma profiles to examine the similarity of the extemporaneous suspension and the commercial tablets.

Results

The amlodipine/valsartan extemporaneous suspension was successfully prepared with acceptable organoleptic properties. The suspension was stable for four-week period preserving its physical and chemical features. The release profiles of valsartan and amlodipine from the suspension were similar to those from source tablet Valzadepine^®. In silico modeling predicted the similarity of the extemporaneous suspension and the commercial tablets.

Conclusion

Amlodipine/valsartan extemporaneous suspension could be prepared from available commercial tablets. Moreover, GastroPlus™ can be applied along with the in vitro dissolution in order to affirm similarity in extemporaneous compounding situations.

Observational Study of Drug Formulation Manipulation in Pediatric Versus Adult Inpatients

OBJECTIVES

Medications often require manipulations to measure and administer the correct dose for pediatric patients. These manipulations pose medication safety risks. The objective of this study was to determine the frequency of drug formulation manipulations in the pediatric inpatient population and compare the findings to a parallel adult inpatient population.

METHODS

Observations were conducted at four sites with 1 day of data collection per week by a randomized schedule for 5 weeks. All pediatric inpatients at each study site were included as well as an equivalent number of medication orders from adult inpatients with similar levels of care. The percentage of medication orders requiring a manipulation were evaluated and compared between pediatric and adult patients.

RESULTS

A total of 15,722 medication orders were analyzed. Drug formulation manipulation was required in 3925 (49.9%) of 7861 pediatric orders versus 1301 of 7861 adult orders (16.6%) (P < 0.05). By pediatric service, drug manipulations were required most frequently (71.5% of orders) in the neonatal intensive care unit. The most common dosage forms requiring manipulation for pediatric patients were oral liquids (45.7% of orders) and intravenous medications (44.6% of orders). By pediatric patient age, drug manipulation was required most often in patients aged 1 to 12 months (69.8% of orders).

CONCLUSIONS

Drug formulation manipulation was three times more common in pediatric inpatient practice compared with adult inpatient practice in this study. This study demonstrated a statistically significant difference in the prevalence of drug formulation manipulation between pediatric and adult inpatients.

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.

Quantitative prediction of the bitterness of atomoxetine hydrochloride and taste-masked using hydroxypropyl-β-cyclodextrin: A biosensor evaluation and interaction study

The bitterness of a drug is a major challenge for patient acceptability and compliance, especially for children. Due to the toxicity of medication, a human taste panel test has certain limitations. Atomoxetine hydrochloride (HCl), which is used for the treatment of attention deficit/hyperactivity disorder (ADHD), has an extremely bitter taste. The aim of this work is to quantitatively predict the bitterness of atomoxetine HCl by a biosensor system. Based on the mechanism of detection of the electronic tongue (E-tongue), the bitterness of atomoxetine HCl was evaluated, and it was found that its bitterness was similar to that of quinine HCl. The bitterness threshold of atomoxetine HCl was 8.61 µg/ml based on the Change of membrane Potential caused by Adsorption (CPA) value of the BT0 sensor. In this study, the taste-masking efficiency of 2-hydroxypropyl-β-cyclodextrin (HP-β-CyD) was assessed by Euclidean distances on a principle component analysis (PCA) map with the SA402B Taste Sensing System, and the host-guest interactions were investigated by differential scanning calorimetry (DSC), powder X-ray diffraction (XRD), nuclear magnetic resonance (NMR) spectroscopy and scanning electron microscopy (SEM). Biosensor evaluation and characterization of the inclusion complex indicated that atomoxetine HCl could actively react with 2-hydroxypropyl-β-cyclodextrin.

Selective laser sintering 3D printing - an overview of the technology and pharmaceutical applications

Food and Drug Administration (FDA) has approved a drug product (Spritam®) and many medical devices manufactured by three-dimensional printing (3DP) processes for human use. There is immense potential to print personalized medicines using 3DP. Many 3DP methods have been reported in the literature for pharmaceutical applications. However, selective laser sintering (SLS) printing has remained least explored for pharmaceutical applications. There are many advantages and challenges in adopting a SLS method for fabrication of personalized medicines. Solvent-free nature, availability of FDA approved thermoplastic polymer/excipients (currently used in hot melt-extrusion process), minimal/no post-processing step, etc. are some of the advantages of the SLS printing process. Major challenges of the technology are requirement of at least one thermoplastic component in the formulation and thermal stability of drug and excipients. This review provides an overview of the SLS printing method, excipient requirements, process monitoring, quality defects, regulatory aspects, and potential pharmaceutical applications.

Preparation and characterization of a powder manufactured by spray drying milk based formulations for the delivery of theophylline for pediatric use

The study considered different fat content cow milks to deliver theophylline orally. Powders were obtained by spray drying theophylline dispersed in fresh milk according to a full factorial design of experiments. The correlation of the independent (milk fat content, skimmed to whole milk, theophylline fraction, and drying temperature) with the dependent (yield of the process and residual moisture content of the powder, particle size and distribution, density, surface polarity and theophylline content) variables enabled the construction of a mathematical model and a desirability function to predict the optimized levels of the variables. Good predictability was achieved for density, fairly good for yield, moisture content, surface polarity and yield whereas theophylline content and particle size were poorly predicted. Powders with up to 60% theophylline presented spherical (3.7 µm) and narrow sized distribution particles, with high density (1.6 g/cm^-3) in high yields (>70%), stable for 6 month (25 °C/65%RH) in a closed container and for no longer than 2 day, after reconstitution in water due to bacteria growth (no pathogens) without signs of crystallinity. Preparations obtained with low fat milk were less stable than high fat content milk. Therefore, fresh milk can be transformed into stable powder compositions to prepare oral solid/liquid dosage forms to deliver individualized doses of theophylline.

Classification of WHO Essential Oral Medicines for Children Applying a Provisional Pediatric Biopharmaceutics Classification System

The objective was using the Essential Medicines List for children by the World Health Organization (WHO) to create a pediatric biopharmaceutics classification system (pBCS) of the oral drugs included in the Essential Medicines List by the World Health Organization and to compare our results with the BCS for adults (aBCS). Several methods to estimate the oral drug dose in different pediatric groups were used to calculate dose number (Do) and solubility (high/low). The estimation of the gastrointestinal water volume was adapted to each pediatric group. Provisional permeability classification was done by comparison of each drug lipophilicity versus metoprolol as the model drug of high permeability. As a result, 24.5% of the included drugs moved from the favorable to unfavorable class (i.e., from high to low solubility). Observed changes point out potential differences in product performance in pediatrics compared to adults, due to changes in the limiting factors for absorption. BCS Class Changes 1 to 2 or 3 to 4 are indicative of drugs that could be more sensitive to the choice of appropriate excipient in the development process. Validating a pBCS for each age group would provide a valuable tool to apply in specific pediatric formulation design by reducing time and costs and avoiding unnecessary pediatric experiments restricted due to ethical reasons. Additionally, pBCS could minimize the associated risks to the use of adult medicines or pharmaceutical compound formulations.

Protocol for a systematic evaluation of pediatric pharmacy development and pediatric pharmacy experts' research area in China

BACKGROUND

The pediatric pharmacy research status of children's hospitals in China is still unknown. Our previous findings suggest the regional differences in academic level in tertiary (grade III level A) children's hospitals in China.

METHODS

This systemic evaluation described in this protocol will be conducted to follow the Cochrane Handbook. We will perform a systemic literature search of relevant databases including Chinese databases (CNKI, Wanfang Data, VIP Paper Check System) and English databases (Medline, EMbase, Cochrane Library) from inception to December 31, 2018. The search strategy will be enacted according to the guidance offered from the Cochrane Handbook. Two rounds of searches will be conducted to prevent the omission of relevant literature. A pre-set grading standard will be used to give calculation weight (W) to evaluate the quality of each article. Data synthesis will be performed using STATA software (version 13.1, Statacorp, College Station, Texas). Pediatric pharmacy development index (PPDI) of each hospital will be used to evaluate the pediatric pharmacy development in each tertiary children's hospitals. The cumulative calculation weight (∑W) and annual calculation weight (∑yearW) will be used to evaluate the academic level of pharmaceutical departments in different tertiary children's hospitals. Subgroup analysis will be performed to compare the number of different types of articles published between different hospitals base on different research areas such as policy research, basic research, and clinical research.

RESULTS

In this article, we will evaluate pediatric pharmacy development and the research area of pediatric pharmacy experts in China. Based on the results from this research, we will analyze the professional backgrounds of pediatric pharmacy experts from 23 tertiary children's hospitals in China. According to the contents and research directions of literature published by the pediatric pharmacy experts in these 23 hospitals, we will determine the professional field of pediatric pharmacy experts and establish an expert database. In the process of formulating the related national or local policies in the future, the expert database will be selected accurately to reach the expert consensus.

CONCLUSION

Our study will provide a comprehensive picture of pediatric pharmacy development in China. The pediatrics pharmacy expert's database constructed by this study will be used to build consensus on pediatric pharmacology in the future.

Biopharmaceutical optimization in neglected diseases for paediatric patients by applying the provisional paediatric biopharmaceutical classification system

AIMS

Unavailability and lack of appropriate, effective and safe formulations are common problems in paediatric therapeutics. Key factors such as swallowing abilities, organoleptic preferences and dosage requirements determine the need for optimization of formulations. The provisional Biopharmaceutics Classification System (BCS) can be used in paediatric formulation design as a risk analysis and optimization tool. The objective of this study was to classify six neglected tropical disease drugs following a provisional paediatric BCS (pBCS) classification adapted to three paediatric subpopulations (neonates, infants and children).

METHODS

Albendazole, benznidazole, ivermectin, nifurtimox, praziquantel and proguanil were selected from the 5th edition of the Model List of Essential Medicines for Children from the World Health Organization. Paediatric drug solubility classification was based on dose number calculation. Provisional permeability classification was based on log P comparison versus metoprolol log P value, assuming passive diffusion absorption mechanisms and no changes in passive membrane permeability between paediatric patients and adults. pBCS classes were estimated for each drug, according to different doses and volumes adapted for each age stage and were compared to the adult classification.

RESULTS

All six drugs were classified into provisional pBCS in the three paediatric subpopulations. Three drugs maintained the same classification as for adults, ivermectin and benznidazole changed solubility class from low to high in neonates and proguanil changed from low to high solubility in all age stages.

CONCLUSION

Provisional pBCS classification of these six drugs shows potential changes in the limiting factors in oral absorption in paediatrics, depending on age stage, compared to the adult population. This valuable information will aid the optimization of paediatric dosing and formulations and can identify bioinequivalence risks when comparing different formulations and paediatric populations.

Assessment of swallowability and palatability of oral dosage forms in children: Report from an M-CERSI pediatric formulation workshop

The acceptability of pediatric pharmaceutical products to patients and their caregivers can have a profound impact on the resulting therapeutic outcome. However, existing methodology and approaches used for acceptability assessments for pediatric products is fragmented, making robust and consistent product evaluations difficult. A pediatric formulation development workshop took place in Washington, DC in June 2016 through the University of Maryland's Center of Excellence in Regulatory Science and Innovation (M-CERSI). A session at the workshop was dedicated to acceptability assessments and focused on two major elements that affect the overall acceptability of oral medicines, namely swallowability and palatability. The session started with presentations to provide an overview of literature, background and current state on swallowability and palatability assessments. Five parallel breakout discussions followed the presentations on each element, focusing on three overarching themes, risk-based approaches, methodology and product factors. This article reports the key outcomes of the workshop related to swallowability and palatability assessments.

Quantification of theophylline or paracetamol in milk matrices by high-performance liquid chromatography

A simple, accurate and sensitive high-performance liquid chromatography (HPLC) method was developed, validated and applied to the determination of either theophylline or paracetamol in milk-based samples. The method allowed drug quantification in fresh and powdered milk with a relatively short run time of analysis and it was also successfully applied to the quantification of the drugs in solid dosage forms intended for pediatric use. Moreover, the main significant advantages over other published works are the simplicity of the sample preparation, reduced assay time and sample loss. The method meets the International Conference on Harmonization guideline for analytical methods validation regarding specificity, linearity, accuracy, precision, specificity and robustness as required by health authorities and applied by industry while designing and marketing new drug products. The technique encompasses the separation of the analytes with a reverse phase C₁₈ column under isocratic conditions and UV detection at 272 nm and 243 nm, respectively, for theophylline and paracetamol. The lower limit of quantification for both drugs was determined as 0.2 µg/mL and the between-batch accuracy was approximately 99.7%. This HPLC method allows quantification of theophylline and paracetamol in milk matrices and it can be applied in the design, development and production of milk-based pediatric dosage forms.

Neonatal Safety Information Reported to the FDA During Drug Development Studies

BACKGROUND

Relatively few neonatal drug development studies have been conducted, but an increase is expected with the enactment of the Food and Drug Administration Safety and Innovation Act (FDASIA). Understanding the safety of drugs studied in neonates is complicated by the unique nature of the population and the level of illness. The objective of this study was to examine neonatal safety data submitted to the FDA in studies pursuant to the Best Pharmaceuticals for Children Act (BPCA) and the Pediatric Research Equity Act (PREA) between 1998 and 2015.

METHODS

FDA databases were searched for BPCA and/or PREA studies that enrolled neonates. Studies that enrolled a minimum of 3 neonates were analyzed for the presence and content of neonatal safety data.

RESULTS

The analysis identified 40 drugs that were studied in 3 or more neonates. Of the 40 drugs, 36 drugs received a pediatric labeling change as a result of studies between 1998 and 2015, that included information from studies including neonates. Fourteen drugs were approved for use in neonates. Clinical trials for 20 of the drugs reported serious adverse events (SAEs) in neonates. The SAEs primarily involved cardiovascular events such as bradycardia and/or hypotension or laboratory abnormalities such as anemia, neutropenia, and electrolyte disturbances. Deaths were reported during studies of 9 drugs.

CONCLUSIONS

Our analysis revealed that SAEs were reported in studies involving 20 of the 40 drugs evaluated in neonates, with deaths identified in 9 of those studies. Patients enrolled in studies were often critically ill, which complicated determination of whether an adverse event was drug-related. We conclude that the traditional means for collecting safety information in drug development trials needs to be adjusted for neonates and will require the collaboration of regulators, industry, and the clinical and research communities to establish appropriate definitions and reporting strategies for the neonatal population.

Buccal Dosage Forms: General Considerations for Pediatric Patients

The development of an appropriate dosage form for pediatric patients needs to take into account several aspects, since adult drug biodistribution differs from that of pediatrics. In recent years, buccal administration has become an attractive route, having different dosage forms under development including tablets, lozenges, films, and solutions among others. Furthermore, the buccal epithelium can allow quick access to systemic circulation, which could be used for a rapid onset of action. For pediatric patients, dosage forms to be placed in the oral cavity have higher requirements for palatability to increase acceptance and therapy compliance. Therefore, an understanding of the excipients required and their functions and properties needs to be particularly addressed. This review is focused on the differences and requirements relevant to buccal administration for pediatric patients (compared to adults) and how novel dosage forms can be less invasive and more acceptable alternatives.

Formulation of orodispersible films for paediatric therapy: investigation of feasibility and stability for tetrabenazine as drug model

Objectives

Orodispersible films (ODF) were formulated to facilitate tetrabenazine (TBZ) administration to paediatric population for the treatment of hyperkinetic movement disorders.

Methods

ODF were obtained by solvent casting/evaporation method using four different polymers (HPMC, PVP, pullulan and HEC). Physicochemical, mechanical and biopharmaceutical characterizations as well as API state in ODF by thermal analysis were investigated to define and compare formulations. ODF stability was also monitored during 6 months to follow evolution of properties.

Key findings

Analyses at T0 showed few differences between formulations: results of physicochemical and mechanical characterizations were almost similar for each formulation and TBZ appeared at the amorphous state in all cases. ODF delivery system allowed a major improvement of TBZ dissolution profile in buccal conditions compared with pure drug. However, after 3 and 6 months of stability, a TBZ recrystallization occurred for formulations based on PVP and HEC associated with a decrease of drug release in saliva conditions.

Conclusions

HPMC-ODF (F1) appeared as the best formulation. Indeed, physicochemical, mechanical and biopharmaceutical characteristic remained intact. In addition, TBZ remained in amorphous state during stability study.

Production and characterization of spray-dried theophylline powders prepared from fresh milk for potential use in paediatrics

OBJECTIVE

This work evaluates the potential of using fresh milk to deliver theophylline to children.

METHODS

Theophylline-fresh milk systems were prepared using different solids ratios (0 : 1-1 : 0) and three fat contents in commercial milks (low, medium and high), which were spray-dried at different inlet air temperatures (T_inlet - 105, 130 and 150 °C). The process was evaluated for yield and the resulting powders for moisture content (MC), particle size and shape, density and wettability. Theophylline-milk potential interactions (differential scanning calorimetry (DSC) and FT-IR) and chemical (theophylline content) and microbiological stability of powders (shelf and in-use) were also evaluated.

KEY FINDINGS

The production yield (13.6-76.0%), MC (0.0-10.3%) and contact angles in water (77.29-93.51°) were significantly (P < 0.05) affected by T_inlet , but no differences were found concerning the mean particle size (3.0-4.3 μm) of the different powders. The milk fat content significantly (P < 0.05) impacted on the density (1.244-1.552 g/cm³ ). Theophylline content remained stable after 6 months of storage, before extemporaneous reconstitution. After reconstitution in water, low-fat milk samples (stored at 4 °C) met the microbial pharmacopoeia criteria for up to 7 days. No theophylline-milk components interaction was observed.

CONCLUSION

Spray-dried milk-composed powders may be used as vehicles for theophylline delivery in paediatrics following further characterization and in-vivo evaluation.

Development of flexible and dispersible oral formulations containing praziquantel for potential schistosomiasis treatment of pre-school age children

Praziquantel (PZQ), an anthelmintic drug used in developing countries for the treatment of schistosome infections, was processed using the fluid bed wet granulation technology to prepare fast dispersible granules, as an appropriate and flexible dosage form for pre-school-aged children. Granulation experiments were performed incorporating PZQ either in the powder mixture, according to the traditional way, or in the liquid phase containing wetting agents. In the powder mixture several excipients were tested: Flowlac 100 as filler, Galeniq 721 (isomalt) and Neosorb P 100 T (D-sorbitol) as sweeteners and PVP K30 as binder; while in the liquid phase Lutrol F68, Cremophor RH 40 or Tween 80 as surfactants were investigated. Different formulations loaded with 10% w/w (batches 1-8) and 20% w/w of PZQ (batches 9-13) were produced The majority of granules displayed good flow properties and uniform drug content. X-ray powder diffraction showed that PZQ remained in its original crystalline state, while differential scanning calorimetry and Fourier transform-infrared analysis evidenced the formation of chemical interactions among the ingredients. The solubilisation test performed in non-sink condition to reproduce the actual condition in which a child of 4 years takes the medicine revealed that granules quickly formed a very fine suspension in water (dV90=39.9 μm). Although after the granulation process the solubility of raw PZQ was not increased, adding the aqueous suspension to 500 ml of buffer solution of pH 1.5, simulating the fasted state of a child, 50% of the drug was dissolved after 30 min. After granule manipulation with milk and fruit juices, no PZQ degradation was observed during time. Finally, the selected granule formulation provided evidence to be stable even at hot and very humid climate (30°C/75% RH), at least for the examined time.

Design of pediatric oral formulations with a low proportion of methadone or phenobarbital for the treatment of neonatal abstinence syndrome

CONTEXT

Elaboration of oral liquid formulations is the best alternative when no marketed forms are available for pediatrics.

OBJECTIVE

The development, characterization and stability evaluation of methadone (MI, MII, MIII) and phenobarbital (PI, PII) can be used for the treatment of neonatal abstinence syndrome (NAS).

MATERIAL AND METHODS

A standard operating procedure was established and parameters such as appearance, pH, rheological behavior and drug content were evaluated at three temperatures for 90 days.

RESULTS AND DISCUSSION

Changes in color of phenobarbital made necessary the storage below 25 °C. pH did not change in methadone solutions and was able to maintain phenobarbital solubilized. Degradation data at 4 °C fitted to Plateau equation followed by one phase decay. MI was stable for 60 days at the three temperatures; MII for 90 days at 4 and 25 °C and 60 days at 40 °C; MIII for 60 days at 4 °C, 15 days at 25 °C and 7 days at 4 °C. PI was stable for 60 days at 4 °C and 30 days at 25 °C. PII was stable for 7 days at 4 and 25 °C. All solutions met microbial specifications.

CONCLUSION

A correct dosage for the treatment of NAS was guaranteed.

Use of pharmacogenomics in pediatric renal transplant recipients

Transplant recipients receive potent immunosuppressive drugs in order to prevent graft rejection. Therapeutic drug monitoring is the current approach to guide the dosing of calcineurin inhibitors, mammalian target of rapamycin inhibitors (mTORi) and mofetil mycophenolate. Target concentrations used in pediatric patients are extrapolated from adult studies. Gene polymorphisms in metabolizing enzymes and drug transporters such as cytochromes CYP3A4 and CYP3A5, UDP-glucuronosyl transferase, and P-glycoprotein are known to influence the pharmacokinetics and dose requirements of immunosuppressants. The implications of pharmacogenomics in this patient population is discussed. Genetic information can help with achieving target concentrations in the early post-transplant period, avoiding adverse drug reactions and drug-drug interactions. Evidence about genetic studies and transplant outcomes is revised.