Reflection on the Pharmaceutical Formulation Challenges Associated with a Paediatric Investigation Plan for an Off-Patent Drug

Acceptability of small-sized oblong tablets in comparison to syrup and mini-tablets in infants and toddlers: A randomized controlled trial

OBJECTIVE

There is limited evidence for the acceptability of various drug formulations holding the potential to improve medicines administration to children. Suitable formulations need to meet the requirements of pediatric patients. Previous studies have demonstrated the acceptance of mini-tablets. Oblong tablets may carry more active ingredient content per unit than mini-tablets and could be an important alternative when the drug substance requires administration of higher doses. The primary objective was to demonstrate non-inferiority of acceptability of oblong tablets in comparison to 3 ml glucose syrup in children aged 1 to 5 years. Secondary objectives were investigation of acceptability, swallowability and palatability of mini-tablets, oblong tablets and glucose syrup in children between 1 and 5 years.

METHODS

An open, randomized, single dose two-way cross-over design in two parallel study arms was applied. 280 children were stratified to one of five age groups and randomized to receiving one oblong tablet (2.5 × 6 mm) in comparison either to 3 ml glucose syrup or to three mini-tablets (2 × 2 mm). Acceptability and swallowability were assessed according to pre-defined evaluation criteria. The application of the formulations was video documented to evaluate the palatability.

RESULTS

As primary objective, non-inferiority was observed regarding acceptability of the oblong tablet compared to syrup in all age groups (84.4% vs 80.1%, difference 4,29% points with 95% CI of -3.00%,11.57%). For swallowability, superiority of the oblong tablet compared to syrup could be shown (74.5% vs. 53.2%, difference 21.26% points, 95% CI of 11.29%, 31.23%). Regarding palatability, <10% of children demonstrated unpleasant reaction after intake of the oblong tablet or mini-tablets as graded by both raters, however, in contrast up to 40% of children after intake of syrup.

CONCLUSION

Oblong tablets are a promising, safe alternative to liquid drug formulations and administration of multiple mini-tablets in children.

Transfer and scale-up of the manufacturing of orodispersible mini-tablets from a compaction simulator to an industrial rotary tablet press

Orodispersible mini-tablets (ODMTs) are a promising dosage form for the pediatric use showing increasing interest from pharmaceutical industry. However, a scale-up process for ODMTs from a compaction simulator to a rotary tablet press following FDA and EMA guidelines has not been performed and investigated yet. Isomalt (galenIQ™721) and Ludiflash® both excipients with proven suitability for the development of ODMTs have been investigated in transfer and scale-up from a compaction simulator to a rotary tablet press. ODMTs with isomalt and Ludiflash® were produced on the rotary tablet press monitoring the product temperature over time and assessing the properties of the residual powder in the feed shoe. Critical quality attributes like tensile strength, mass and disintegration time were evaluated. The transfer from compaction simulator to rotary tablet press succeeded as for both excipients similar disintegration times, tabletability and compactibility profiles were obtained. However, during scale-up, disintegration time significantly increases over time for both excipients. Monitoring of the product temperature revealed that with increasing batch size the product temperature increases as well having a significant impact on disintegration time. The properties of ODMTs produced with the residual powder are comparable in tabletability and disintegration time compared with ODMTs produced from fresh powder.

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.

Profiling gene expression dynamics underpinning conventional testing approaches to better inform pre-clinical evaluation of an age appropriate spironolactone formulation

There is a need to accelerate paediatric formulation evaluation and enhance quality of early stage data in drug development to alleviate the information pinch point present between formulation development and clinical evaluation. This present work reports application of DNA microarrays as a high throughput screening tool identifying markers for prediction of bioavailability and formulation driven physiological responses. With a focus on enhancing paediatric medicine provision, an oral liquid spironolactone suspension was formulated addressing a paediatric target product profile. Caco-2 cells cultured on transwell inserts were implemented in transport assays in vitro and DNA microarrays were used to examine gene expression modulation. Wistar rats were used to derive in vivo bioavailability data. In vitro, genomic, and in vivo data sets were concurrently evaluated linking drug transport and the genomic fingerprint generated by spironolactone formulation exposure. Significant changes in gene expression are reported as a result of formulation exposure. These include genes coding for ATP-binding cassette (ABC) transporters, solute carrier (SLC) transporters, cytochrome P450 (CYP) enzymes, and carboxylesterase enzymes. Genomic findings better inform pre-clinical understanding of pharmacokinetic and pharmacodynamic responses to spironolactone and its active metabolites than current in vitro drug transport assays alone.

Orphan Formulations for Pediatric Use: Development and Stability Control of Two Sildenafil Citrate Solutions for the Treatment of Pulmonary Hypertension

Sildenafil citrate causes vasodilatation, relaxation of the smooth muscle, and reduction of pulmonary arterial pressure. The latter property makes sildenafil citrate efficient for the treatment of cardiovascular diseases, including pulmonary arterial hypertension. Pediatric patients with pulmonary arterial hypertension are more susceptible to errors in drug administration than adults because of a lack of suitable drug dosages. Thus, the purpose of this study was to develop stable (chemically and microbiologically) sildenafil citrate drop liquid formulation, suitable for pediatric patients (including diabetics), ensuring safety during preparation and storing and improving palatability by using milk as a carrier for administration. The significant factors that affect the sildenafil solubility were evaluated by applying a Plackett-Burman design using two levels with six variables. The experiment showed that the type of buffer and glycerin content influenced the sildenafil solubility. The developed formulations proved to be stable for 6 months at all three assayed conditions (40± 2°C, 75 ± 5% RH; 25± 2°C, 60 ± 5% RH; and 4 ± 2°C). The microbiological tests fit with the requirement of the pharmacopeia at day 0 and 90 and even more at day 180. Finally, the palatability assay showed that 0.82 mL of the formulation containing buffer phosphate, 20% glycerin, and 4 mg mL^-1 of sildenafil citrate diluted in 4.8 mL milk (which fits the medium pediatric dose) presented similar palatability to milk alone, and no precipitate or turbidity was observed. Graphical abstract.

New orodispersible mini-tablets for paediatric use - A comparison of isomalt with a mannitol based co-processed excipient

The development of orodispersible mini-tablets (ODMTs) for paediatric use has gained importance within recent years as European authorities set up regulations for developing suitable and palatable dosage forms for paediatric patients. Polyols like mannitol and isomalt are frequently used in the manufacture of tablets where sensory properties have to be taken into account. In literature, ODTMs based on a commercialized co-processed excipient based on mannitol (Ludiflash®) have been already described. Isomalt is known for its pleasant sensory properties and therefore appears to be a good candidate for ODMTs. The feasibility of the direct compression grade of isomalt for the manufacture of ODMTs was assessed and compared to Ludiflash®. Hydrochlorothiazide and enalapril maleate were chosen as model drugs and compressed to 2 mm mini-tablets. ODMTs could be obtained fulfilling the criteria of Ph.Eur. with disintegration times of 180 s or even the FDA limit of 30 s. Dissolution studies and mass variation were fulfilled for all mini-tablets. Acceptance values (AV) ≤ 15 were achieved for formulations based on both isomalt and Ludiflash®. Stability data showed the change of disintegration time and tensile strength as a function of storing time, condition and excipient. Both excipients showed their potential for ODMTs for paediatric use.

Suitability of new drugs registered in Brazil from 2003 to 2013 for pediatric age groups

Objective

To analyze suitability of new drugs registered in Brazil from 2003 to 2013 for pediatric age groups.

Methods

A descriptive study of drugs with pediatric indication included in a retrospective cohort of new drugs registered in Brazil. The evaluation of drug suitability for the pediatric age group was performed using the following criteria: suitability of dosage form and capacity to deliver the recommended dose. The drugs were considered adequate for the pediatric age groups when they met both criteria. The statistical analysis included calculation of frequencies and proportions.

Results

Suitability due to the drug capacity to deliver the recommended dose was greater than 80% across all age groups. Regarding suitability of the dosage form, we identified that the older the age group, the greater suitability for pediatric use. Concerning the drugs presented in solid dosage form, we showed that half were classified as inadequate for one or more pediatric age groups to whom they were indicated. The adequacy of drugs to the pediatric age group was 64.3% for preschool children, 66.7% for full-term newborns, 66.7% for premature newborns, and over 70% for other age groups.

Conclusion

Drugs for children aged under 6 years were less often adequate, considering the dosage form and capacity to provide the recommended dose. The availability and proportional suitability of medicines for pediatric use are greater for older age groups, according to age groups the drug is registered for.

Continuous inkjet printing of enalapril maleate onto orodispersible film formulations

Piezoelectric inkjet printing onto orodispersible films (ODFs) was proven to be a successful technique applying flexible doses of active pharmaceutical ingredients (APIs) onto edible substrates. The reported API printing and ODF production was conducted in a non-continuous production approach. Within this study, drug-free and hydrochlorothiazide (HCT) containing ODFs should be imprinted in-line with enalapril maleate (EM) ink during continuous ODF production. Macrogol inks based on various solvents and solvent-water mixtures were developed providing dynamic viscosities from 7 to 17 mPa*s. Water based inks contained 1.25%, methanol based inks up to 10% EM. Both inks could be printed (500-1000 Hz) during continuous ODF production. No EM recrystallization was observed for water-based inks. Mechanical properties were not affected by drug printing using various firing frequencies. ODF imprinted with water-based EM inks contained 0.04 mg EM/6 cm². EM amount can be increased to a paediatric therapeutic dose of 0.5 mg EM utilizing methanol-based inks. These inks were successfully printed onto HCT ODFs resulting in a therapeutically relevant fixed-dose combination. No EM migration into the HCT layer could be observed. In conclusion, it was feasible to print EM doses onto drug-free and HCT ODFs during an in-line continuous manufacturing process.