3D-Printed Veterinary Dosage Forms-A Comparative Study of Three Semi-Solid Extrusion 3D Printers

Exploring pet owners' attitudes toward compounded and human approved medicines: a questionnaire based pilot study

With the growing global pet population and increased spending on veterinary care, compounded medications offer customized, often more suitable and affordable treatment options compared to the limited available veterinary medications. This research aims to understand pet owners' attitudes towards compounded medications, focusing on their challenges and needs. A total of 300 respondents from the territory of Novi Sad, province of Vojvodina, Republic of Serbia completed the questionnaire, through face-to-face interviews at veterinary clinics. Pet owners stated that the majority of companion animals were dogs (66.7%), followed by cats (22.8%). A significant portion of them received medication in the past five years (70.7%), while nearly half of them were human-approved (47.9%) out of which more than half (55%) of the pets received antimicrobials for systemic use. Although the majority of pets did not receive compounded medication (79.8%), respondents believed that both they and their pets would benefit from it. Only small fraction of respondents knew that local pharmacies had the ability to compound medications for pets (14.5%). In the era of personalized medicine, compounded medication for specialized needs play an important role providing optimum therapy for veterinary patients. However, limitations persist, including variability in formulation quality, limited regulatory oversight, and challenges in ensuring consistency in potency and stability, as well as decreased efficacy for certain drugs and the challenges related to the lack of pharmacokinetic data for some administration routes. By customizing treatments for individual veterinary patients, we can optimize antimicrobial use, reduce the selective pressure that drives resistance, and enhance patient outcomes, while acknowledging the need for careful oversight and quality control in compounding practices to ensure safety and efficacy.

The comprehensive review on 3D printing- pharmaceutical drug delivery and personalized food and nutrition

Three-dimensional printing is one of the emerging technologies that is gaining interest from the pharmaceutical industry as it provides an opportunity to customize drugs according to each patient's needs. Combining different active pharmaceutical ingredients, using different geometries, and providing sustained release enhances the effectiveness of medicine. One of the most innovative uses of 3D printing is producing fabrics, medical devices, medical implants, orthoses, and prostheses. This review summarizes the various 3D printing techniques such as stereolithography, inkjet printing, thermal inkjet printing, fused deposition modelling, extrusion printing, semi-solid extrusion printing, selective laser sintering, and hot-melt extrusion. Also, discusses the drug relies profile and its mechanisms, characteristics, and applications of the most common types of 3D printed API formulations and its recent development. Here, Authors also, summarizes the central flow of 3D food printing process and knowledge extension toward personalized nutrition.

The Formulation and Evaluation of Customized Prednisolone Gel Tablets Prepared by an Automated Extrusion-Based Material Deposition Method

Background/Objectives: An automated extrusion-based material deposition is a contemporary and rapid method for pharmaceutical dose-dispensing and preparing (printing) individualized solid dosage forms. The aim of this study was to investigate and gain knowledge of the feasibility of automated extrusion-based material deposition technology in preparing customized prednisolone (PRD)-loaded gel tablets for veterinary applications (primarily for dogs and cats). Methods: The PRD loads of the extrusion-based deposited gel tablets were 0.5% and 1.0%, and the target weights of tablets were 0.250 g, 0.500 g, and 1.000 g. The effects of the material deposition processes on the physical solid state, in vitro dissolution, and the physicochemical stability of PRD gel tablets were investigated. Results: The small-sized gel tablets presented a uniform round shape with an exceptionally smooth outer surface texture. The actual average weight of the tablets (n = 10) was very close to the target weight, showing the precision of the process. We found that PRD was in a pseudopolymorphic sesquihydrate form (instead of an initial PRD crystalline form II) in the gel tablets. In all the immediate-release gel tablets studied, more than 70% of the drug load was released within 30 min. The soft texture and dimensions of gel tablets affected the dissolution behaviour in vitro, suggesting the need for further development and standardization of a dissolution test method for such gel tablets. A short-term storage stability study revealed that the content of PRD did not decrease within 3 months. Conclusions: Automated extrusion-based material deposition is a feasible method for the rapid preparation of gel tablets intended for veterinary applications. In addition, the present technology and gel tablets could be used in pediatric and personalized medicine where precise dosing is crucial.

Bacterial cellulose films for L-asparaginase delivery to melanoma cells

L-asparaginase (L-ASNase) is an enzyme that catalyzes the hydrolysis of L-asparagine to L-aspartic acid and ammonia and is used to treat acute lymphoblastic leukemia. It is also toxic to the cells of some solid tumors, including melanoma cells. Immobilization of this enzyme can improve its activity against melanoma tumor cells. In this work, the properties of bacterial cellulose (BC) and feasibility of BC films as a new carrier for immobilized L-ASNase were investigated. Different values of growth time were used to obtain BC films with different thicknesses and porosities, which determine the water content and the ability to adsorb and release L-ASNase. Fourier transform infrared spectroscopy confirmed the adsorption of the enzyme on the BC films. The total activity of adsorbed L-ASNase and its release were investigated for films grown for 48, 72 or 96 h. BC films grown for 96 h showed the most pronounced release as described by zero-order and Korsmayer-Peppas models. The release was characterized by controlled diffusion where the drug was released at a constant rate. BC films with immobilized L-ASNase could induce cytotoxicity in A875 human melanoma cells. With further development, immobilization of L-ASNase on BC may become a potent strategy for anticancer drug delivery to superficial tumors.

Characterization of Prototype Gummy Formulations Provides Insight into Setting Quality Standards

Gummy formulations are considered suitable alternatives to traditional oral dosage forms like tablets and capsules due to their merits that include chewability, softness/flexibility, improved drug release, administration without water, appealing organoleptic properties, better patient compliance, easy preparation and usefulness for persons of different ages (e.g. children). Though there is increasing interest in gummy formulations containing drugs, measurable parameters, and specification limits for evaluating their quality are scarce. Quality check forms an essential part of the pharmaceutical development process because drug products must be distributed as consistently stable, safe, and therapeutically effective entities. Consequently, some quality parameters that could contribute to the overall performance of typical gummy formulations were investigated employing six brands of non-medicinal gummies as specimens. Accordingly, key physicochemical and micromechanical characteristics namely adhesiveness (0.009 - 0.028 mJ), adhesive force (0.009 - 0.055 N), chewiness (2.780 - 6.753 N), cohesiveness (0.910 - 0.990), hardness (2.984 - 7.453 N), springiness (0.960 - 1.000), and resilience (0.388 - 0.572), matrix firmness - compression load (2.653 - 6.753 N) and work done (3.288 - 6.829 mJ), rupture (5.315 - 29.016 N), moisture content (< 5%), weight uniformity (< 2.5 g; < 7.5% deviation), and intraoral dissolution pH (≥ 3.5 ≤ 6.8) were quantified to identify measures that may potentially function as specification limits and serve as prospective reference points for evaluating the quality of gummy formulations. Findings from this work contribute to ongoing efforts to standardize the quality control strategies for gummy formulations, particularly those intended for oral drug delivery.

Pimobendan controlled release guar gum printlets: Tailoring drug doses for personalised veterinary medicines

Treating chronic heart diseases in dogs is challenging due to variations in mass within and between species. Pimobendan (PBD), a veterinary drug only, is prescribed in specific cases of chronic heart disease in dogs and is available on the market in only a few different doses. Furthermore, the therapy itself is challenging due to the large size of the chewable tablets and the requirement for twice-daily administration. The development of customised and on-demand PBD medicines by three-dimensional (3D) printing has been proposed to circumvent these disadvantages. In this study, we designed controlled-release flavoured printlets containing PBD. We evaluated the use of two natural polymers, guar or xanthan gums, as the main component of the printing inks. Guar gum showed the better rheological behavior and printability by semisolid extrusion. The printlets were produced in three different shapes and sizes to allow dose customisation. Guar gum printlets showed a PBD controlled release profile, regardless of their shape or size. Therefore, we have demonstrated a novel approach for controlling PBD drug release and tailoring the dose by employing a natural polymer to produce 3D-printed tablets. This study represents a significant step towards the development of 3D-printed guar gum controlled-release formulations for veterinary applications.

3D-printed prednisolone phosphate suppositories with tunable dose and rapid release for the treatment of inflammatory bowel disease

Established medicines are often not tailored to the needs of the pediatric population, causing difficulties with administration or dosing. Three-dimensional (3D) printing technology allows novel approaches for compounding of personalized medicine, as is exemplified in this study for the automated compounding of rectal preparations for children. We investigated the material requirements to print prednisolone phosphate-loaded suppositories with tunable dose and rapid drug release for the treatment of inflammatory bowel diseases. Three formulations containing 4 % w/w prednisolone sodium phosphate (PSP) and different amounts of hydroxypropyl cellulose (HPC) and mannitol as excipients were printed as suppositories with a fused deposition modeling (FDM) 3D-printer. Dissolution studies showed that the PSP release rate was increased when higher weight fractions of mannitol were added as a pore former, with 90 % drug release within 30 min for mannitol 48 % w/w. We further printed suppositories with 48 % mannitol with different infill densities and dimensions to tune the dose. Our findings demonstrated that 3D-printed suppositories with PSP doses ranging from 6 to 30 mg could be compounded without notably affecting the dissolution kinetics, ensuring equivalent therapeutic efficacies for different doses.

Personalizing oral delivery of nanoformed piroxicam by semi-solid extrusion 3D printing

Semi-solid extrusion (SSE) 3D printing enables flexible designs and dose sizes to be printed on demand and is a suitable tool for fabricating personalized dosage forms. Controlled Expansion of Supercritical Solution (CESS®) is a particle size reduction technology, and it produces particles of a pure active pharmaceutical ingredient (API) in a dry state, suspendable in the printing ink. In the current study, as a model API of poorly water-soluble drug, nanoformed piroxicam (nanoPRX) prepared by CESS® was accommodated in hydroxypropyl methylcellulose- or hydroxypropyl cellulose-based ink formulations to warrant the printability in SSE 3D printing. Importantly, care must be taken when developing nanoPRX formulations to avoid changes in their polymorphic form or particle size. Printing inks suitable for SSE 3D printing that successfully stabilized the nanoPRX were developed. The inks were printed into films with escalating doses with exceptional accuracy. The original polymorphic form of nanoPRX in the prepared dosage forms was not affected by the manufacturing process. In addition, the conducted stability study showed that the nanoPRX in the prepared dosage form remained stable for at least three months from printing. Overall, the study rationalizes that with nanoparticle-based printing inks, superior dose control for the production of personalized dosage forms of poorly water-soluble drugs at the point-of-care can be achieved.

A novel injectable fibromodulin-releasing granular hydrogel for tendon healing and functional recovery

A crucial component of the musculoskeletal system, the tendon is one of the most commonly injured tissues in the body. In severe cases, the ruptured tendon leads to permanent dysfunction. Although many efforts have been devoted to seeking a safe and efficient treatment for enhancing tendon healing, currently existing treatments have not yet achieved a major clinical improvement. Here, an injectable granular hyaluronic acid (gHA)-hydrogel is engineered to deliver fibromodulin (FMOD)-a bioactive extracellular matrix (ECM) that enhances tenocyte mobility and optimizes the surrounding ECM assembly for tendon healing. The FMOD-releasing granular HA (FMOD/gHA)-hydrogel exhibits unique characteristics that are desired for both patients and health providers, such as permitting a microinvasive application and displaying a burst-to-sustained two-phase release of FMOD, which leads to a prompt FMOD delivery followed by a constant dose-maintaining period. Importantly, the generated FMOD-releasing granular HA hydrogel significantly augmented tendon-healing in a fully-ruptured rat's Achilles tendon model histologically, mechanically, and functionally. Particularly, the breaking strength of the wounded tendon and the gait performance of treated rats returns to the same normal level as the healthy controls. In summary, a novel effective FMOD/gHA-hydrogel is developed in response to the urgent demand for promoting tendon healing.

Orodispersible Film (ODF) Platform Based on Maltodextrin for Therapeutical Applications

Orodispersible film (ODF) is a new dosage form that disperses rapidly in the mouth without water or swallowing. The main ingredient of an ODF is a polymer that can be both of natural or synthetic origin. Maltodextrin is a natural polymer, mainly used in pharmaceutical and nutraceutical fields. This review aims to examine the literature regarding ODFs based on maltodextrin as the platform for developing new products for therapeutical application. ODFs based on maltodextrin contain plasticizers that enhance their flexibility and reduce their brittleness. Surfactants; fillers, such as homopolymer and copolymer of vinylacetate; flavour and sweetener were introduced to improve ODF characteristics. Both water-soluble and insoluble APIs were introduced up to 100 mg per dosage unit. The solvent casting method and hot-melt extrusion are the most useful techniques for preparing ODFs. In particular, the solvent casting method allows manufacturing processes to be developed from a lab scale to an industrial scale. ODFs based on maltodextrin are characterized in terms of mechanical properties, dissolution rate, taste and stability. ODFs made of maltodextrin, developed by IBSA, were tested in vivo to evaluate their bioequivalence and efficacy and were demonstrated to be a valid alternative to the marketed oral dosage forms.

Innovations in Chewable Formulations: The Novelty and Applications of 3D Printing in Drug Product Design

Since their introduction, chewable dosage forms have gained traction due to their ability to facilitate swallowing, especially in paediatric, geriatric and dysphagia patients. Their benefits stretch beyond human use to also include veterinary applications, improving administration and palatability in different animal species. Despite their advantages, current chewable formulations do not account for individualised dosing and palatability preferences. In light of this, three-dimensional (3D) printing, and in particular the semi-solid extrusion technology, has been suggested as a novel manufacturing method for producing customised chewable dosage forms. This advanced approach offers flexibility for selecting patient-specific doses, excipients, and organoleptic properties, which are critical for ensuring efficacy, safety and adherence to the treatment. This review provides an overview of the latest advancements in chewable dosage forms for human and veterinary use, highlighting the motivations behind their use and covering formulation considerations, as well as regulatory aspects.

Compounding Tailored Veterinary Chewable Tablets Close to the Point-of-Care by Means of 3D Printing

Certain patient populations receive insufficient medicinal treatment due to a lack of commercially available products. The number of approved veterinary products is limited, making animals a patient population with suboptimal medicinal treatments available. To answer to this unmet need, compounding and off-label use of human-marketed products are practiced. Both of which have a significant risk of preparation errors. Hence, there is a dire demand to find and implement a more automated approach to the accurate, precise, and rapid production of veterinary dosage forms close to the point-of-care. This study aimed to assess the use of semi-solid extrusion-based 3D printing for the preparation of tailored doses of theophylline in the form of a chewable dosage form suitable for veterinary use. This study proved that semi-solid extrusion-based 3D printing could successfully be utilized to manufacture pet-friendly, chewable theophylline-loaded tablets. The prepared dosage forms showed a high correlation (R² = 0.9973) between the designed size and obtained drug amount and met the USP and Ph. Eur. content uniformity criteria. Furthermore, the stability study showed the dosage form being stable and able to be used for up to three months after printing.

The Evolution of the 3D-Printed Drug Delivery Systems: A Review

Since the appearance of the 3D printing in the 1980s it has revolutionized many research fields including the pharmaceutical industry. The main goal is to manufacture complex, personalized products in a low-cost manufacturing process on-demand. In the last few decades, 3D printing has attracted the attention of numerous research groups for the manufacturing of different drug delivery systems. Since the 2015 approval of the first 3D-printed drug product, the number of publications has multiplied. In our review, we focused on summarizing the evolution of the produced drug delivery systems in the last 20 years and especially in the last 5 years. The drug delivery systems are sub-grouped into tablets, capsules, orodispersible films, implants, transdermal delivery systems, microneedles, vaginal drug delivery systems, and micro- and nanoscale dosage forms. Our classification may provide guidance for researchers to more easily examine the publications and to find further research directions.

Semisolid Extrusion 3D Printing of Propranolol Hydrochloride Gummy Chewable Tablets: an Innovative Approach to Prepare Personalized Medicine for Pediatrics

The demand for personalized medicine has received extensive attention, especially in pediatric preparations. An emerging technology, extrusion-based 3D printing, is highly attractive in the field of personalized medicine. In this study, we prepared propranolol hydrochloride (PR) gummy chewable tablets tailored for children by semisolid extrusion (SSE) 3D printing technology to meet personalized medicine needs in pediatrics. In this study, the effects of critical formulation variables on the rheological properties and printability of gum materials were investigated by constructing a full-factorial design. In addition, the masticatory properties, thermal stability, and disintegration time of the preparations were evaluated. Bitterness inhibitors were used to mask the bitterness of the preparations. The results of the full-factorial design showed that the amount of gelatin and carrageenan were the key factors in the formulation. Gelatin can improve printability and masticatory properties, carrageenan can improve thermal stability, and accelerate the disintegration of preparations; therefore, a reasonable combination of both could satisfactorily meet the demand for high-quality 3D printing. γ-Aminobutyric acid can reduce the bitterness of gummy chewable tablets to improve medication compliance and the determined formulation (F7) met the quality requirements. In conclusion, the gum material has excellent potential as an extrusion material for 3D printing. The dosage can be adjusted flexibly by the model shape and size. 3D printing has broad prospects in pediatric preparations.

The Effects of Solid Particle Containing Inks on the Printing Quality of Porous Pharmaceutical Structures Fabricated by 3D Semi-Solid Extrusion Printing

Purpose

Semi-solid extrusion (SSE) 3D printing has potential pharmaceutical applications for producing personalised medicine. However, the effects of ink properties and drug incorporation on the quality of printed medication have not been thoroughly studied, particularly for porous geometries. This study aimed to investigate the effects of the presence of solid drug particles in SSE inks on the printing quality of porous structures.

Method

The rheological behaviour of model inks of paracetamol (PCM)-hypromellose (HPMC) with different drug loadings were investigated and correlated to their printing qualities.

Results

For the inks with PCM loading above the drug solubility in which suspended solid drug particulates were present, the results confirmed that PCM loading and particle size significantly affected the ink viscosities at a low shear rate. At a low shear rate, the highest viscosity was identified when the highest drug loading and the smallest PCM particles were incorporated into the inks. However, the results indicated that the SSE printing parameters and printing quality of porous structures (with less porous structural deformation) have no clear correlation with the shear viscosity data, but a strong correlation with the dynamic oscillatory rheology of the inks.

Conclusion

The key rheological parameters including storage modulus, loss modulus and complex viscosity of the ink increased with increasing drug loading for the inks containing solid drug particles. However, decreasing the particle size did not have a clear effect on the oscillatory rheology of the inks which can be potentially used for optimising the SSE 3D printing quality of porous geometries.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11095-022-03299-7.

Additive Manufacturing Strategies for Personalized Drug Delivery Systems and Medical Devices: Fused Filament Fabrication and Semi Solid Extrusion

Novel additive manufacturing (AM) techniques and particularly 3D printing (3DP) have achieved a decade of success in pharmaceutical and biomedical fields. Highly innovative personalized therapeutical solutions may be designed and manufactured through a layer-by-layer approach starting from a digital model realized according to the needs of a specific patient or a patient group. The combination of patient-tailored drug dose, dosage, or diagnostic form (shape and size) and drug release adjustment has the potential to ensure the optimal patient therapy. Among the different 3D printing techniques, extrusion-based technologies, such as fused filament fabrication (FFF) and semi solid extrusion (SSE), are the most investigated for their high versatility, precision, feasibility, and cheapness. This review provides an overview on different 3DP techniques to produce personalized drug delivery systems and medical devices, highlighting, for each method, the critical printing process parameters, the main starting materials, as well as advantages and limitations. Furthermore, the recent developments of fused filament fabrication and semi solid extrusion 3DP are discussed. In this regard, the current state of the art, based on a detailed literature survey of the different 3D products printed via extrusion-based techniques, envisioning future directions in the clinical applications and diffusion of such systems, is summarized.

Drug-loaded mesoporous silica on carboxymethyl cellulose hydrogel: Development of innovative 3D printed hydrophilic films

3D printing has been explored as an emerging technology for the development of versatile and printable materials for drug delivery. However, the alliance of 3D printing and nanomaterials has, to date, been little explored in pharmaceutics. Herein, a mesoporous silica with nanostructured pores, SBA-15, was used as a drug carrier for triamcinolone acetonide, a hydrophobic drug, with the aim of incorporating the drug formulation in a hydrophilic printable ink. The adsorption of the drug in the SBA-15 pores was confirmed by the decrease in its surface area and pore volume, along with an increase in the apparent aqueous solubility of triamcinolone acetonide, as shown by in vitro release studies. Thereafter, a hydrophilic ink composed of carboxymethyl cellulose containing drug-loaded SBA-15 was formulated and 3D printed as hydrophilic polymeric film using the semisolid extrusion technique (SSE). The 3D printed films showed complete drug release after 12 h, and the presence of the triamcinolone acetonide-loaded SBA-15 improved their in vitro mucoadhesion, suggesting their promising application in oral mucosa treatments. Besides representing an innovative platform to develop water-based mucoadhesive formulations containing a hydrophobic drug, this is the first report proposing the development of SSE 3D printed nanomedicines containing drug-loaded mesoporous silica.

Natural Hydrogel-Based Bio-Inks for 3D Bioprinting in Tissue Engineering: A Review

Three-dimensional (3D) printing is well acknowledged to constitute an important technology in tissue engineering, largely due to the increasing global demand for organ replacement and tissue regeneration. In 3D bioprinting, which is a step ahead of 3D biomaterial printing, the ink employed is impregnated with cells, without compromising ink printability. This allows for immediate scaffold cellularization and generation of complex structures. The use of cell-laden inks or bio-inks provides the opportunity for enhanced cell differentiation for organ fabrication and regeneration. Recognizing the importance of such bio-inks, the current study comprehensively explores the state of the art of the utilization of bio-inks based on natural polymers (biopolymers), such as cellulose, agarose, alginate, decellularized matrix, in 3D bioprinting. Discussions regarding progress in bioprinting, techniques and approaches employed in the bioprinting of natural polymers, and limitations and prospects concerning future trends in human-scale tissue and organ fabrication are also presented.

Recent progress in three-dimensionally-printed dosage forms from a pharmacist perspective

OBJECTIVE

Additive manufacturing (AM), commonly known as 3D printing (3DP), has opened new frontiers in pharmaceutical applications. This review is aimed to summarise the recent development of 3D-printed dosage forms, from a pharmacists' perspective.

METHODS

Keywords including additive manufacturing, 3D printing and drug delivery were used for literature search in PubMed, Excerpta Medica Database (EMBASE) and Web of Science, to identify articles published in the year 2020.

RESULTS

For each 3DP study, the active pharmaceutical ingredients, 3D printers and materials used for the printing were tabulated and discussed. 3DP has found its applications in various dosage forms for oral delivery, transdermal delivery, rectal delivery, vaginal delivery, implant and bone scaffolding. Several topics were discussed in detail, namely patient-specific dosing, customisable drug administration, multidrug approach, varying drug release, compounding pharmacy, regulatory progress and future perspectives. AM is expected to become a common tool in compounding pharmacies to make polypills and personalised medications.

CONCLUSION

3DP is an enabling tool to fabricate dosage forms with intricate structure designs, tailored dosing, drug combinations and controlled release, all of which lend it to be highly conducive to personalisation, thereby revolutionising the future of pharmacy practice.

Orodispersible films: Conception to quality by design

Orodispersible films (ODFs) are ultra-thin, stamp-sized, elegant, portable and patient-centric pharmaceutical dosage forms that do not need water to be ingested. They are particularly useful for paediatric and geriatric patient populations with special needs such as dysphagia, Parkinson's disease, and oral cancer. Accordingly, they hold tremendous potential in gaining patient compliance, convenience and pharmacotherapy. In the present review, conception and evolution of ODFs as a product and its technology are discussed. The review continues by providing overview about the potential of ODFs as carriers for delivering drugs, herbal extracts, probiotics and vaccines. Besides, strategies employed in drug cargo loading, taste masking of bitter drugs and enhancing drug stability are discussed. Finally, the review concludes by providing a brief overview about quality by design (QbD) principles in development of ODFs.

Polymeric long-acting drug delivery systems (LADDS) for treatment of chronic diseases: Inserts, patches, wafers, and implants

Non-oral long-acting drug delivery systems (LADDS) encompass a range of technologies for precisely delivering drug molecules into target tissues either through the systemic circulation or via localized injections for treating chronic diseases like diabetes, cancer, and brain disorders as well as for age-related eye diseases. LADDS have been shown to prolong drug release from 24 h up to 3 years depending on characteristics of the drug and delivery system. LADDS can offer potentially safer, more effective, and patient friendly treatment options compared to more invasive modes of drug administration such as repeated injections or minor surgical intervention. Whilst there is no single technology or definition that can comprehensively embrace LADDS; for the purposes of this review, these systems include solid implants, inserts, transdermal patches, wafers and in situ forming delivery systems. This review covers common chronic illnesses, where candidate drugs have been incorporated into LADDS, examples of marketed long-acting pharmaceuticals, as well as newly emerging technologies, used in the fabrication of LADDS.

Translating 3D printed pharmaceuticals: From hype to real-world clinical applications

Three-dimensional (3D) printing is a revolutionary technology that is disrupting pharmaceutical development by enabling the production of personalised printlets (3D printed drug products) on demand. By creating small batches of dose flexible medicines, this versatile technology offers significant advantages for clinical practice and drug development, namely the ability to personalise medicines to individual patient needs, as well as expedite drug development timelines within preclinical studies through to first-in-human (FIH) and Phase I/II clinical trials. Despite the widely demonstrated benefits of 3D printing pharmaceuticals, the clinical potential of the technology is yet to be realised. In this timely review, we provide an overview of the latest cutting-edge investigations in 3D printing pharmaceuticals in the pre-clinical and clinical arena and offer a forward-looking approach towards strategies to further aid the translation of 3D printing into the clinic.

Polymeric-based drug delivery systems for veterinary use: State of the art

One of the challenges to the success of veterinary pharmacotherapy is the limited number of drugs and dosage forms available exclusively to this market, due to the interspecies variability of animals, such as anatomy, physiology, pharmacokinetics, and pharmacodynamics. For this reason, studies in this area have become a highlight, since they are still scarce in comparison with those on human drug use. To overcome many limitations related to the bioavailability, efficacy, and safety of pharmacotherapy in animals, especially livestock and domestic animals, polymers-based drug delivery systems are promising tools if they guarantee greater selectivity and less toxicity in dosage forms. In addition, these tools may be developed according to the great interspecies variability. To contribute to these discussions, this paper provides an updated review of the major polymer-based drug delivery systems projected for veterinary use. Traditional and innovative drug delivery systems based on polymers are presented, with an emphasis on films, microparticles, micelles, nanogels, nanoparticles, tablets, implants and hydrogel-based drug delivery systems. We discuss important concepts for the veterinarian about the mechanisms of drug release and, for the pharmacist, the advantages in the development of pharmaceutical forms for the animal population. Finally, challenges and opportunities are presented in the field of pharmaceutical dosage forms for veterinary use in response to the interests of the pharmaceutical industry.

Semi-solid extrusion 3D printing in drug delivery and biomedicine: Personalised solutions for healthcare challenges

Three-dimensional (3D) printing is an innovative additive manufacturing technology, capable of fabricating unique structures in a layer-by-layer manner. Semi-solid extrusion (SSE) is a subset of material extrusion 3D printing, and through the sequential deposition of layers of gel or paste creates objects of any desired size and shape. In comparison to other extrusion-based technologies, SSE 3D printing employs low printing temperatures which makes it suitable for drug delivery and biomedical applications, and the use of disposable syringes provides benefits in meeting critical quality requirements for pharmaceutical use. Besides pharmaceutical manufacturing, SSE 3D printing has attracted increasing attention in the field of bioelectronics, particularly in the manufacture of biosensors capable of measuring physiological parameters or as a means to trigger drug release from medical devices. This review begins by highlighting the major printing process parameters and material properties that influence the feasibility of transforming a 3D design into a 3D object, and follows with a discussion on the current SSE 3D printing developments and their applications in the fields of pharmaceutics, bioprinting and bioelectronics. Finally, the advantages and limitations of this technology are explored, before focusing on its potential clinical applications and suitability for preparing personalised medicines.