Emollient product design: objective measurements of formulation structure, texture and performance, and subjective assessments of user acceptability

Comparison of lotions, creams, gels and ointments for the treatment of childhood eczema: the BEE RCT

Background

Emollients are recommended for children with eczema (atopic eczema/dermatitis). A lack of head-to-head comparisons of the effectiveness and acceptability of the different types of emollients has resulted in a 'trial and error' approach to prescribing.

Objective

To compare the effectiveness and acceptability of four commonly used types of emollients for the treatment of childhood eczema.

Design

Four group, parallel, individually randomised, superiority randomised clinical trials with a nested qualitative study, completed in 2021. A purposeful sample of parents/children was interviewed at ≈ 4 and ≈ 16 weeks.

Setting

Primary care (78 general practitioner surgeries) in England.

Participants

Children aged between 6 months and 12 years with eczema, of at least mild severity, and with no known sensitivity to the study emollients or their constituents.

Interventions

Study emollients sharing the same characteristics in the four types of lotion, cream, gel or ointment, alongside usual care, and allocated using a web-based randomisation system. Participants were unmasked and the researcher assessing the Eczema Area Severity Index scores was masked.

Main outcome measures

The primary outcome was Patient-Oriented Eczema Measure scores over 16 weeks. The secondary outcomes were Patient-Oriented Eczema Measure scores over 52 weeks, Eczema Area Severity Index score at 16 weeks, quality of life (Atopic Dermatitis Quality of Life, Child Health Utility-9 Dimensions and EuroQol-5 Dimensions, five-level version, scores), Dermatitis Family Impact and satisfaction levels at 16 weeks.

Results

A total of 550 children were randomised to receive lotion (analysed for primary outcome 131/allocated 137), cream (137/140), gel (130/135) or ointment (126/138). At baseline, 86.0% of participants were white and 46.4% were female. The median (interquartile range) age was 4 (2-8) years and the median Patient-Oriented Eczema Measure score was 9.3 (SD 5.5). There was no evidence of a difference in mean Patient-Oriented Eczema Measure scores over the first 16 weeks between emollient types (global p = 0.765): adjusted Patient-Oriented Eczema Measure pairwise differences - cream-lotion 0.42 (95% confidence interval -0.48 to 1.32), gel-lotion 0.17 (95% confidence interval -0.75 to 1.09), ointment-lotion -0.01 (95% confidence interval -0.93 to 0.91), gel-cream -0.25 (95% confidence interval -1.15 to 0.65), ointment-cream -0.43 (95% confidence interval -1.34 to 0.48) and ointment-gel -0.18 (95% confidence interval -1.11 to 0.75). There was no effect modification by parent expectation, age, disease severity or the application of UK diagnostic criteria, and no differences between groups in any of the secondary outcomes. Median weekly use of allocated emollient, non-allocated emollient and topical corticosteroids was similar across groups. Overall satisfaction was highest for lotions and gels. There was no difference in the number of adverse reactions and there were no significant adverse events. In the nested qualitative study (n = 44 parents, n = 25 children), opinions about the acceptability of creams and ointments varied most, yet problems with all types were reported. Effectiveness may be favoured over acceptability. Parents preferred pumps and bottles over tubs and reported improved knowledge about, and use of, emollients as a result of taking part in the trial.

Limitations

Parents and clinicians were unmasked to allocation. The findings may not apply to non-study emollients of the same type or to children from more ethnically diverse backgrounds.

Conclusions

The four emollient types were equally effective. Satisfaction with the same emollient types varies, with different parents/children favouring different ones. Users need to be able to choose from a range of emollient types to find one that suits them.

Future work

Future work could focus on how best to support shared decision-making of different emollient types and evaluations of other paraffin-based, non-paraffin and 'novel' emollients.

Trial registration

This trial is registered as ISRCTN84540529 and EudraCT 2017-000688-34.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (HTA 15/130/07) and will be published in full in Health Technology Assessment; Vol. 27, No. 19. See the NIHR Journals Library website for further project information.

Topical corticosteroid vehicle composition and implications for clinical practice

This narrative review highlights the therapeutic significance of topical corticosteroid (TCS) vehicles and provides subsequent guidance to improve clinical and research outcomes. A greater understanding of the relationship between the topical vehicle, corticosteroid and skin is needed to ensure safer, more effective treatment for patients. Topical vehicles are not inert and can affect TCS bioavailability, due to the ability of their composition to positively or negatively influence skin status and change the physiochemical characteristics of an inherent corticosteroid. However, this principle is not commonly understood, and has contributed to inconsistencies in potency classification systems. This review provides an insight into the research methods and standardization needed to determine TCS product bioavailability. It identifies formulation components responsible for vehicle composition that underpin the quality, stability, compounding and functionalities of vehicle ingredients. This helps to contextualize how topical vehicles can be responsible for clinically significant effects, and how their composition gives products unique properties. In turn, this facilitates a more in-depth understanding of which resources offer information to inform the best selection of TCS products and why products should be prescribed by brand or manufacturer. This review will better equip clinicians and formulary teams to appraise products. It will also inform prescribing of Specials and why products should not be manipulated. The recommendations, accompanied by patient perspectives on using TCS products, assist clinical decision-making. They also identify the need for research into concomitant application of TCS products with other topical therapies.

Development and Study of Semi-Solid Preparations Containing the Model Substance Corticotropin (ACTH): Convenience Application in Neurodegenerative Diseases

Corticotropin (ACTH, previously an adrenocorticotropic hormone) is used in the diagnosis and treatment of pituitary gland disorders, adrenal cortex disorders, and other diseases, including autoimmune polymyositis, systemic lupus erythematosus, rheumatoid arthritis, Crohn’s disease, and ulcerative colitis. So far, the ointment dosage form containing ACTH for use on the skin is unknown. Therefore, it seems appropriate to develop a semi-solid formulation with corticotropin. Emulsion ointments were prepared using an Unguator based on the cream base Lekobaza^® containing corticotropin in different concentrations, and then the physical and chemical parameters of the ointment formulations, such as pH, spreadability, rheological properties, and texture analysis, were evaluated. In addition, a USP apparatus 2 with enhancer cells was utilized to study the in vitro drug release characteristics of the selected formulations. All the ointments obtained were characterized by good spreadability and viscosity. An analysis of the ointment texture was performed and the dependence of the tested parameters on the ACTH content in the ointment was demonstrated. Examination of the structure of the ointment showed that a high concentration of ACTH increases the hardness and adhesiveness of the ointment. In turn, it adversely affects the cohesiveness and elasticity of the ointments tested. The results of the release study showed that ACTH is released the fastest from the formulation with the lowest concentration, while the slowest from the ointment with the highest concentration of ACTH.