Paediatric Formulation: Design and Development

Clinical data required for the approval of pediatric pharmaceuticals in Japan

BACKGROUND

In Japan, the number of pharmaceuticals with pediatric indications is low, and some are approved only in Europe or the USA but not in Japan. As the approval review report by the Japanese health authority contains any detailed items considered for drug approval, this study aimed to analyze the review reports and elucidate data types that facilitate the approval of pediatric drugs in Japan.

METHODS

We identified products approved in Japan, extracted relevant product- and review-related information, and summarized the characteristics of pediatric drug clinical data and drug approval procedures.

RESULTS

Among 625 products (approved 04/2019-02/2024), 171 with pediatric indications were analyzed. The approval review considered orphan drug designation for 56 products, public knowledge-based application for 16 products, mandatory post-marketing surveillance for 42 products, and investigator-initiated studies for 11 products. For only 10 products, confirmatory studies were completed exclusively in Japanese children. Among the other 161 products, extrapolation from non-Japanese children and Japanese adults and/or older children was discussed for 93 and 100 products, respectively. Extrapolation-based reviews focused on ethnic and population factors and consistency of exposure dose, efficacy, and safety. Statistical confirmation is not always necessary for approval. Administrative incentives are often applied, including for orphan drugs and Sakigake designation and public knowledge-based applications.

CONCLUSIONS

The appropriateness or sufficiency of the clinical data package can refer to the PMDA. By considering joining a multinational study and determining the required number of Japanese patients, a path toward the approval of pediatric drugs in Japan can be identified.

Physicochemical and microbiological stability of 40 mg/mL amiodarone hydrochloride oral suspension

PURPOSE

Amiodarone hydrochloride is an antiarrhythmic drug used to treat supraventricular tachycardia. However, there are currently no commercial pediatric forms available to treat young patients. Various oral formulations were previously reported in the literature, but the concentration was lower than the doses prescribed in clinical practice (a loading dose of 500 mg/m2/day for 7-10 days followed by a maintenance dose of 250 mg/m2/day). The objective of this study was to develop an oral liquid formulation of amiodarone hydrochloride at an optimal concentration for use in children and to evaluate its physicochemical and microbiological stability.

METHODS

No commercial suspension vehicle was used, allowing the choice of excipients. Compounding was performed using hydroxypropylmethylcellulose as thickener, potassium sorbate preservative, citric acid/sodium citrate buffer, sodium saccharin as sweetener, and a strawberry flavoring agent. A concentration of 40 mg/mL was selected based on a 5-year compilation of prescribed doses. Analyses performed were the following: visual and microscopic inspection, testing for antimicrobial preservation, osmolality and pH measurements, quantification of amiodarone hydrochloride by a stability-indicating liquid chromatography method, and a microbiological count.

RESULTS

At least 95% of the initial amiodarone hydrochloride remained stable during the 60-day study period under refrigeration. All other tested parameters remained stable at 5 °C. A targeted log reduction of the microorganism inoculum by day 14 and no microbial growth by day 28 were demonstrated in the test for antimicrobial preservation.

CONCLUSION

The stability of 40 mg/mL amiodarone hydrochloride oral suspension was maintained under refrigeration for 60 days before opening bottles and for 1 month after opening bottles.

Oral Gels as an Alternative to Liquid Pediatric Suspensions Compounded from Commercial Tablets

The aim of the study was to propose pharmacy-compounded oral gels as a new and alternative dosage form that is attractive to children as having a better masking taste than syrups and reducing the risk of spilling. The application and physical properties of the gels prepared with cellulose derivatives (hydroxyethylcellulose and carmellose sodium) or carbomers were evaluated. The results of the study showed the most suitable consistency, viscosity, and organoleptic properties for gels prepared with carbomer and cellulose derivatives at concentrations of 0.75% and 2.0%, respectively. The microbial stability of the gels was guaranteed by the use of methylparaben and potassium sorbate. VAL (valsartan) and CC (candesartan cilexetil) tablets, often used off-label in children, were pulverized and suspended in the hydrogel bases, resulting in final drug concentrations of 4 mg/g and 1 mg/g, respectively. There was no significant change in viscosity and consistency parameters when the pulverized tablets were added, and only small changes in viscosity and consistency were observed during 35 days of storage, especially in the gels with sodium carmellose and candesartan. On the basis of the drug assay, an expiry date of 25 °C was recommended: 35 days for valsartan and 14 days for candesartan preparations.

Innovative Pharmaceutical Techniques for Paediatric Dosage Forms: A Systematic Review on 3D Printing, Prilling/Vibration and Microfluidic Platform

The production of paediatric pharmaceutical forms represents a unique challenge within the pharmaceutical industry. The primary goal of these formulations is to ensure therapeutic efficacy, safety, and tolerability in paediatric patients, who have specific physiological needs and characteristics. In recent years, there has been a significant increase in attention towards this area, driven by the need to improve drug administration to children and ensure optimal and specific treatments. Technological innovation has played a crucial role in meeting these requirements, opening new frontiers in the design and production of paediatric pharmaceutical forms. In particular, three emerging technologies have garnered considerable interest and attention within the scientific and industrial community: 3D printing, prilling/vibration, and microfluidics. These technologies offer advanced approaches for the design, production, and customization of paediatric pharmaceutical forms, allowing for more precise dosage modulation, improved solubility, and greater drug acceptability. In this review, we delve into these cutting-edge technologies and their impact on the production of paediatric pharmaceutical forms. We analyse their potential, associated challenges, and recent developments, providing a comprehensive overview of the opportunities that these innovative methodologies offer to the pharmaceutical sector. We examine different pharmaceutical forms generated using these techniques, evaluating their advantages and disadvantages.

Bioavailability assessment of a brompheniramine taste-masked pediatric formulation in a juvenile porcine model

A brompheniramine taste-masked pediatric formulation was developed as part of the National Institutes of Health Pediatric Formulation Initiative to help address low patient compliance caused by the bitter taste of many adult formulations. To confirm that the taste-masked formulation can provide a similar pharmacological effect to the previous marketed adult formulations, a juvenile porcine model was used to screen the model pediatric formulation to compare the bioavailability between the marketed brompheniramine maleate and the taste-masked maleate/tannate formulation. Pigs were dosed orally with both formulations and blood samples were obtained from 0 to 48 h. Plasma samples were prepared and extracted using solid-phase extraction. The mass spectrometer was operated under selected ion monitoring mode. The selected ion monitoring channels were set to m/z 319.1 for brompheniramine and m/z 275.2 for the internal standard chlorpheniramine. Calibration curves were linear over the analytical range 0.2-20 ng/ml (r2 > 0.995) for brompheniramine in plasma. The intra- and inter-day accuracies were between 98.0 and 105% with 5.73% RSD precision. The bioanalytical method was successfully applied to a preclinical bioavailability study. The bioavailability profiles were not significantly different between the two formulations, which demonstrates that taste-masking with tannic acid is a promising approach for formulation modification for pediatric patients.

Questionnaire Study to Investigate the Preferences of Children, Parents, and Healthcare Professionals for Different Formulations of Oral Medicinal Products

Since the acceptability of a medicine can significantly impact therapeutic outcomes, this study aimed to determine and compare the preferences of children, parents, and healthcare professionals for the most commonly used pediatric oral medicine formulations (syrup, mini-tablets, oblong tablets, round tablets) addressing all pediatric age groups, 0-<18 years (y). This survey study employed sex-, age-, and participant group-adapted questionnaires for eight cohorts of participants, i.e., children 6-<12 y, adolescents 12-<18 y, parents of children in four age groups (0-<2 y, 2-<6 y, 6-<12 y, and 12-<18 y), nurses, and pediatricians. Descriptive statistics were used for data analysis. In the age groups 0-<2 y and 2-<6 y, mini-tablets were preferred over syrup by all participants. In the age group 6-12 y, solid dosage forms were also preferred over syrup by all participants. In the age group 12-<18 y, healthcare professionals preferred solid dosage forms over syrup. Parents preferred higher amounts of mini-tablets and syrup compared to round and oblong tablets, while adolescents' preferences did not differentiate between these formulations. Based on the study results and in contrast to current practice, it is suggested to consider solid dosage forms for future age-appropriate medicinal products already for younger age groups.

Exposure to potentially harmful excipients in medications among neonates at a state hospital in Malaysia

OBJECTIVES

This study aimed to determine the incidence, types and predictors of Potentially Harmful Excipients (PHE) exposure among hospitalized neonates.

METHODS

A prospective observational study was conducted from March to April 2022 in neonatal wards at a state hospital in Malaysia. The PHEs of interest were aspartame, benzalkonium chloride, benzyl alcohol, benzoic acid or benzoates, ethanol, parabens, polysorbate 80, propylene glycol, saccharin sodium, sorbitol and sulfites. Product information leaflets (PILs) and summaries of product characteristics (SPCs) were referred to obtain information on active pharmaceutical ingredient, strength, trade name as well as type and amount of the excipients.

RESULTS

A total of 108 neonates were recruited and 97.2% of them were exposed to at least one PHE. Parabens (47.2%) and sulfites (27.5%) were the two most commonly administered PHEs. Benzyl alcohol is contraindicated in neonates but was administered to 8% of neonates in this study. The median daily dose of ethanol (24.11 mg/kg/day, IQR 19.73, 28.49) exceeded the acceptable daily intake (ADI) by four times. However, the dose was not available for all PHEs as this information is not always available in the PIL or SPC. Administration of cardiovascular drugs was associated with a higher risk of exposure to any PHE (OR 6.38, CI 2.75, 14.79, p-value < 0.001).

CONCLUSION

The exposure of PHE among neonates in this study is high with certain PHEs exceeding the ADI. It highlights the need for certain strategies to be implemented to reduce such exposure in neonates.

3D Printing Technology Based on Versatile Gelatin-Carrageenan Gel System for Drug Formulations

Currently, there is a shortage of pediatric medicines on the market, and 3D printing technology can more flexibly produce personalized medicines to meet individual needs. The study developed a child-friendly composite gel ink (carrageenan-gelatin), created 3D models by computer-aided design technology, then produced personalized medicines using 3D printing to improve the safety and accuracy of medication for pediatric patients. An in-depth understanding of the printability of different formulations was obtained by analyzing the rheological and textural properties of different gel inks and observing the microstructure of different gel inks, which guided the formulation optimization. Through formulation optimization, the printability and thermal stability of gel ink were improved, and F6 formulation (carrageenan: 0.65%; gelatin: 12%) was selected as the 3D printing inks. Additionally, a personalized dose linear model was established with the F6 formulation for the production of 3D printed personalized tablets. Moreover, the dissolution tests showed that the 3D printed tablets were able to dissolve more than 85% within 30 min and had similar dissolution profiles to the commercially available tablets. This study demonstrates that 3D printing is an effective manufacturing technique that allows for flexible, rapid, and automated production of personalized formulations.

Palatability Assessment of Carbocysteine Oral Solution Strawberry Taste Versus Carbocysteine Oral Solution Mint Taste: A Blinded Randomized Study

Objective: To compare and evaluate the palatability of two carbocysteine oral solutions (strawberry vs. mint taste) among healthy children aged 2–12 years.

Methods: A randomized, triple-blind, crossover, palatability trial in 42 children aged 2–12 years. All subjects received two preparations of carbocysteine oral solutions (strawberry vs. mint) according to randomized administration sequences, and the administration process was recorded by video. The palatability assessed by emotional valences was performed using a facial action coding system by FaceReader™, which reflected the quantification degree of emotion; a positive value represents positive emotion, and a negative value represents negative emotion. At the same time, a face-to-face interview was conducted for 5- to 12-year-old participants. Then, the taste preferential rates were compared to assess the palatability of two carbocysteine oral solutions.

Results: Forty-two children were enrolled in this study. Twenty children first tasted the carbocysteine oral solution mint taste and then the strawberry taste preparation (M-S sequence), while 22 children tasted the strawberry preparation first and then the mint one (S-M sequence). The emotional valence of mint preparation (−0.9 in M-S and −1.2 in S-M) was both relatively lower than that of strawberry taste (both −0.7 in M-S and S-M) in two sequences; 69.0% (29/42) of participants’ emotional valences for strawberry preparation were higher than those for mint preparation. Among 27 participants aged ≥5 years, the taste preference rate was 88.5% (23/26) for the strawberry preparation (one missing value for the taste preference), and 77.8% of participants (21/27) chose the strawberry preparation if they had to take the medicine one more time.

Conclusion: The carbocysteine oral solution with strawberry taste is an appealing preparation since it was better received by children. The facial action coding system could be an effective alternative for palatability assessment of pediatric pharmaceutical products.

Emerging Challenges and Innovations in Surfactant-mediated Stabilization of Biologic Formulations

Biologics may be subjected to various destabilizing conditions during manufacturing, transportation, storage, and use. Therefore, biologics must be appropriately formulated to meet their desired quality target product profiles. In the formulations of protein-based biologics, one critical component is surfactant. Polysorbate 80 and Polysorbate 20 remain the most commonly used surfactants. Surfactants can stabilize proteins through different mechanisms and help the proteins withstand destabilization stresses. However, the challenges associated with surfactants, for instance, impurities, degradation, and potential triggering of adverse immune responses, have been encountered. Therefore, there are continued efforts to develop novel surfactants to overcome these challenges associated with traditional surfactants. Meanwhile, surfactants have also found their use in formulations of newer and novel modalities, namely, antibody-drug conjugates, bispecific antibodies, and adeno-associated viruses (AAV). This review provides an updated in-depth discussion of surfactants in the above-mentioned areas, namely mechanism of action of surfactants, a critical review of challenges with surfactants and current mitigation approaches, and emerging technologies to develop novel surfactants. In addition, gaps, current mitigations, and future directions have been presented to trigger further discussion and research to facilitate the use and development of novel surfactants.