Orodispersible films: Towards drug delivery in special populations

Towards Printed Pediatric Medicines in Hospital Pharmacies: Comparison of 2D and 3D-Printed Orodispersible Warfarin Films with Conventional Oral Powders in Unit Dose Sachets

To date, the lack of age-appropriate medicines for many indications results in dose manipulation of commercially available dosage forms, commonly resulting in inaccurate doses. Various printing technologies have recently been explored in the pharmaceutical field due to the flexible and precise nature of the techniques. The aim of this study was, therefore, to compare the currently used method to produce patient-tailored warfarin doses at HUS Pharmacy in Finland with two innovative printing techniques. Dosage forms of various strengths (0.1, 0.5, 1, and 2 mg) were prepared utilizing semisolid extrusion 3D printing, inkjet printing and the established compounding procedure for oral powders in unit dose sachets (OPSs). Orodispersible films (ODFs) drug-loaded with warfarin were prepared by means of printing using hydroxypropylcellulose as a film-forming agent. The OPSs consisted of commercially available warfarin tablets and lactose monohydrate as a filler. The ODFs resulted in thin and flexible films showing acceptable ODF properties. Moreover, the printed ODFs displayed improved drug content compared to the established OPSs. All dosage forms were found to be stable over the one-month stability study and suitable for administration through a naso-gastric tube, thus, enabling administration to all possible patient groups in a hospital ward. This work demonstrates the potential of utilizing printing technologies for the production of on-demand patient-specific doses and further discusses the advantages and limitations of each method.

Oral thin films as a remedy for noncompliance in pediatric and geriatric patients

Pediatric and geriatric patients experience swallowing difficulties for traditional oral dosage forms, such as tablets. Further, microbial contamination, chemical stability, unpleasant taste and swallowing large volumes of fluids have led to low therapeutic efficacy and patient noncompliance. The emergence of oral thin films has resulted in dramatic improvements in compliance and drug therapy outcomes in pediatric and geriatric patients. Oral thin films do not require water for administration, are readily hydrated upon contact with saliva, adhere to the mucosa and disintegrate ideally under 1 min. This article provides an overview of oral thin films, modern trends in their formulation and characterization, available commercial products, information to fill knowledge gaps and future potential and economic prospects of oral thin film technology, with emphasis on their use in the pediatric and geriatric patient groups.

How to assess orodispersible film quality? A review of applied methods and their modifications

In recent years, there has been a tendency toward creating innovative, easy to use and patient-friendly drug delivery systems suitable for every consumer profile, which would ensure safety, stability and acceptability of a drug. One of the relatively novel and promising approaches is the manufacture of orodispersible films (ODFs), which is an upcoming area of interest in drug delivery. They are defined as polymer thin films that disintegrate in the oral cavity within seconds, without drinking water or chewing, and eliminate the risk of choking. Gaining special usefulness in therapies of children and the elderly, ODFs seem to fill the gap in the range of preparations available for these groups of patients. As no detailed monography of ODFs including testing methods and uniform requirements has been presented in any of the pharmacopoeias to date, the aim of this article is to give an overview of the applied testing methods, their modifications and innovative approaches related to ODF quality assessment.

Localized drug delivery with mono and bilayered mucoadhesive films and wafers for oral mucosal infections

Local drug delivery into oral cavity offers many advantages over systemic administration in treatment of the oral infections. In this study, monolayer and bilayered mucoadhesive film and wafer formulations were developed as local drug delivery platforms using chitosan and hydroxypropyl methylcellulose (HPMC). Cefuroxime axetil (CA) was used as the model drug. Surface morphology, mechanical strength, water uptake, in vitro adhesion, disintegration and in vitro release properties of the formulations were investigated. Furthermore, antimicrobial activity of the formulations was evaluated against E. coli and S. aureus. HPMC based formulations were found to disintegrate within <30 min whereas chitosan based formulations remained intact up to 6 h. Significantly higher drug release was obtained with wafer formulations. Antimicrobial activity was found to increase in presence of chitosan, and HPMC was also observed to contribute to this action. Bilayered wafer formulation, with adhesive chitosan backing layer and HPMC based drug loaded layer, providing prolonged drug release and suitable adhesive properties, with suitable mechanical strength, would be suggested as a promising local delivery system for treatment of the infections in the oral cavity.

In Vitro Oral Cavity Model for Screening the Disintegration Behavior of Orodispersible Films: A Bespoke Design

The availability of biorelevant methods for the disintegration study of pharmaceutical orodispersible dosage forms is required. The disintegration of orodispersibles should be assessed using in vitro methods that can combine biorelevant volumes of disintegration medium and mechanical stresses mimicking in vivo conditions. This study proposes an adaptation of a mechanical oral cavity model for the disintegration study of orodispersible films. A periodic compression is applied to the sample in the presence of a biorelevant volume of artificial salivary fluid. Four orodispersible film samples (P1, C1, P2, and C2), differing in polymer type and molecular weight, and Listerine^® were tested and filmed during disintegration. An image analysis program was developed for the determination of the volume reduction of the film matrix over time, as a descriptor of film disintegration behavior. Samples P1 and Listerine^® showed a volume reduction at 180 s of >90%, C1, P2, and C2 were 85%, 48%, and 37%, respectively. The model was able to detect differences in the disintegration behavior of the 4 samples, and results were comparable with the benchmark product. The concept of disintegration behavior of orodispersible films was introduced for the first time as an informative method for the study of orodispersible dosage form.

Crystallisation in printed droplets: understanding crystallisation of d-mannitol polymorphs

Crystallising d-mannitol in printed droplets provides new insights into understanding the effect of foreign surfaces on the formation of its polymorphs.

Stability and compatibility of Basmisanil granules co-administered with soft food

Co-administration of solid oral dosage forms with soft food or beverages is commonly used to facilitate administration and to improve compliance in the paediatric and geriatric population and in patient groups with swallowing difficulties. The present case study was conducted to investigate the compatibility, stability and dissolution of Basmisanil administered as granules mixed with different soft food matrices. The data were generated to justify dosing instructions, according which Basmisanil should be sprinkled on or mixed with one tablespoon of soft food to aid swallowing. Different soft food types were selected to cover a broad range of various food components (e.g. fat, protein, carbohydrates, fiber and water) and pH. Active content and degradation products of the active substance were determined after mixing the granules with the semisolid food matrix and after two hours of storage under ambient conditions, respectively. In-vitro dissolution tests of granule/food mixtures were also conducted. Furthermore, the stability of the API polymorph was evaluated. Basmisanil shows good chemical stability when the granules are mixed with soft food and consumed within two hours. No polymorphic conversion (anhydrate to monohydrate) could be detected in the granule/food mixtures after preparation and after storage up to 24 h. The in-vitro dissolution of the API from the granules was not adversely affected by the presence of the food matrix. All results were comparable regardless of the tested food matrix. The results do not prohibit the administration of the granules with soft food to the patient.

Development of Orodispersible Films Containing Benzydamine Hydrochloride Using a Modified Solvent Casting Method

The aim of this study was to develop benzydamine hydrochloride-loaded orodispersible films using the modification of a solvent casting method. An innovative approach was developed when the drying process of a small-scale production was used based on a heated inert base for casting the film. During this process, two types of film-forming maltodextrins for rapid drug delivery were used. They were plasticized with two different polyols (xylitol and sorbitol). Superdisintegrant Kollidon® CL-F was tested as an excipient that can induce faster disintegration of the prepared films. The influence of the formulation parameters (dextrose equivalent of film-forming maltodextrins, a type of plasticizer, and the presence of superdisintegrant) on the disintegration time, mechanical properties, and moisture content of films was statistically evaluated using a multivariate data analysis. Orodispersible films containing maltodextrin with lower dextrose equivalent value showed better mechanical properties (tensile strength ranged from 886.6 ± 30.2 to 1484.2 ± 226.9 N cm^-2), lower moisture content (0.5 ± 0.0 to 1.2 ± 0.2%), and shorter disintegration time (17.6 ± 2.9 to 27.8 ± 2.8 s). Films plasticized with xylitol showed shorter disintegration time (17.6 ± 2.9 to 29.2 ± 3.8 s) than films containing sorbitol (23.8 ± 2.9 to 31.7 ± 3.9 s). With the addition of superdisintegrant Kollidon® CL-F, a significant influence on disintegration time was not observed. The modified solvent casting method shows great promise in a small-scale laboratory production of orodispersible films, e.g., in a pharmacy lab.

Printing T3 and T4 oral drug combinations as a novel strategy for hypothyroidism

Hypothyroidism is a chronic and debilitating disease that is estimated to affect 3% of the general population. Clinical experience has highlighted the synergistic value of combining triiodothyronine (T₃) and thyroxine (T₄) for persistent or recurrent symptoms. However, thus far a platform that enables the simultaneous and independent dosing of more than one drug for oral administration has not been developed. Thermal inkjet (TIJ) 2D printing is a potential solution to enable the dual deposition of T₃ and T₄ onto orodispersible films (ODFs) for therapy personalisation. In this study, a two-cartridge TIJ printer was modified such that it could print separate solutions of T₃ and T₄. Dose adjustments were achieved by printing solutions adjacent to each other, enabling therapeutic T₃ (15-50 μg) and T₄ dosages (60-180 μg) to be successfully printed. Excellent linearity was observed between the theoretical and measured dose for both T₃ and T₄ (R² = 0.982 and 0.985, respectively) by changing the length of the print objective (Y-value). Rapid disintegration of the ODFs was achieved (<45 s). As such, this study for the first time demonstrates the ability to produce personalised dose combinations by TIJ printing T₃ and T₄ onto the same substrate for oral administration.

Isoniazid-loaded orodispersible strips: Methodical design, optimization and in vitro-in silico characterization

Drug treatment remains the most effective global approach to managing and preventing tuberculosis. This work focuses on formulating and evaluating an optimized polyvinyl alcohol-polyethylene glycol based orodispersible strip containing isoniazid, a first-line anti-tubercular agent. A solvent casting method guided through a Taguchi experimental design was employed in the fabrication, optimization and characterization of the orodispersible strip. The optimized strip was physically amalgamated with a monolayer, uniformly distributed surface geometry. It was 159.2 ± 3.0 µm thick, weighed 36.9 ± 0.3 mg, had an isoniazid load of 99.5 ± 0.8%w/w, disintegration and dissolution times of 17.6 ± 0.9 s and 5.5 ± 0.1 min respectively. In vitro crystallinity, thermal measurements and in silico thermodynamic predictions confirmed the strip's intrinsic miscibility, thermodynamic stability and amorphous nature. A Korsmeyer-Peppas (r = 0.99; n > 1 = 1.07) fitted kinetics typified by an initial burst release of 49.4 ± 1.9% at 4 min and a total of 99.8 ± 3.3% at 30 min was noted. Ex vivo isoniazid permeation through porcine buccal mucosa was bi-phasic and characterized by a 50.4 ± 3.8% surge and 95.6 ± 2.9% at 5 and 120 min respectively. The strip was physicomechanically robust, environmentally stable and non-cytotoxic.

New formulation and approach for mucoadhesive buccal film of rizatriptan benzoate

Mucoadhesive buccal film is developed as a promising dosage form, which has prominent advantages because of drug delivery through buccal mucosa. New formulation of buccal films containing rizatriptan benzoate (RB) was prepared by solvent casting method using various concentrations of hydroxypropyl methylcellulose (HPMC K4M), polyvinyl alcohol (PVA), polyethylene oxide (PEO), glycerol, stevia, and goat buccal mucosa used as a model membrane. In this work, the effect of polymers and plasticizer concentrations on drug release profile, disintegration and dissolution time, mechanical properties, and mucoadhesive characteristics of films was studied. Scanning electron microscopy analysis revealed uniform distribution of RB in film formulations. Chemical compounds and thermal analysis of the films were studied by Fourier transform infrared spectroscopy and differential scanning calorimetry, respectively. The buccal films produced were uniform in drug content and thickness. All formulations have in vitro release of 98–102% between 40 and 80 min. Also ex vivo mucoadhesion strength was in the range of 0.205 ± 0.035 to 0.790 ± 0.014 N for all formulations. A formulation consisting RB (50 mg), HPMC K4M, PVA, and PEO (63 mg), glycerol (1.5 ml), stevia (5 mg) was selected as our optimum composition. More satisfactory results were obtained in terms of disintegration and dissolution time, mechanical properties, and mucoadhesive characteristics. In addition, it showed about 99.89% RB released in 45 min. The results suggest that RB-loaded mucoadhesive buccal films could be a potential candidate to achieve optimum drug release for effective treatment of migraine.