Very-Rapidly Dissolving Printlets of Isoniazid Manufactured by SLS 3D Printing: In Vitro and In Vivo Characterization

3D printed tablets for personalised dose titration of prednisone using selective laser sintering

The recent clinical emergence of 3D printing in pharmaceutical development has opened the possibility for a shift away from standardised medication dosing and towards more precise and personalised medicines and treatments. Prednisone is a commonly utilised steroidal anti-inflammatory drug that often requires complex combinations of tablets to achieve dosage regimens and titration, which can lead to poor adherence and adverse effects. This study utilised selective laser sintering (SLS) 3D printing to produce custom prednisone tablets of various clinically relevant doses with high accuracy. Incorporating 3D models of different sizes, five doses of prednisone tablet were successfully printed ranging between 5 and 25 mg. Across the five distinct dosage groups, the SLS printed prednisone met conventional tablet manufacturing and British Pharmacopoeial quality standard criteria. When compared to commercially available prednisone tablets, the SLS printed tablets demonstrated a similar immediate release profile with complete drug release within 25 min. This proof-of-concept study demonstrates the capability of SLS 3D printing to produce custom therapeutic doses of clinically relevant medications, showing the viability of translation to clinical practice for the provision of personalised medications.

FDM 3D-printed oral dosage form of prednisolone - Improvement of printability and influencing drug release

The customisation of solid oral dosage forms is essential for maximising efficacy, minimising harm, and providing patient-centred care. Fused Deposition Modelling (FDM) 3D-printing (3DP) is current research of interest within the pharmaceutical industry to produce personalised 3D printed oral "tablets" (printlets) by utilising drug-loaded polymer filaments. Due to the novelty of such technique within the pharmaceutical industry, the printability of many dosage forms and the effect of physical parameters such as the geometry of printlets requires additional research. In this work, the printability of prednisolone (PDL) loaded semi-crystalline polyvinyl alcohol (PVAl) filament was investigated via various characterisation and analytical techniques, such as optical microscopy, x-ray micro-computed tomography (μCT), powder x-ray diffraction (pXRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), melt rheology (at 215 ℃), and dissolution testing. Using these techniques, it was shown that the viscosity of the prednisolone-loaded polyvinyl alcohol (PVAl-PDL) drastically decreased with increasing shear rate beyond 5 s-1 due to the presence of prednisolone which affected the macro and microscopic qualities of the printlets upon using the same printing settings (215 ℃) as for the polymer only. It was further shown that the geometry (structure) of the printlets had a significant influence on the drug release with the most influential factor being the contact surface area to volume ratio in contrast to other parameters. The results presented in this work show the ability of FDM 3DP within the pharmaceutical industry and the possibility to control the drug release, and the macro and microstructure qualities of the printlets.

Spiked Systems for Colonic Drug Delivery: Architectural Opportunities and Quality Assurance of Selective Laser Sintering

Additive manufacturing has been a breakthrough therapy for the pharmaceutical industry raising opportunities for long-quested properties, such as controlled drug-delivery. The aim of this study was to explore the geometrical capabilities of selective laser sintering (SLS) by creating spiked (tapered-edged) drug-loaded specimens for administration in colon. Poly(vinyl alcohol) (PVA) was used as the binding material and loperamide hydrochloride was incorporated as the active ingredient. Printing was feasible without the addition of a sintering agent or other additives. Innovative printing protocols were developed to help improve the quality of the obtained products. Intentional vibrations were applied on the powder bed through rapid movements of the printing platform in order to facilitate rigidity and consistency of the printed objects. The drug-loaded products had physicochemical properties that met the pharmacopoeia standards and exhibited good biocompatibility. The behavior of spiked balls (spherical objects with prominent spikes) and their retention time in the colon was assessed using a custom ex vivo intestinal setup. The spiked balls showed favorable mucoadhesive properties over the unspiked ones. No movement on the tissue was recorded for the spiked balls, and specimens with more spikes exhibited longer retention times and potentially, enhanced bioavailability. Our results suggest that SLS 3D printing is a versatile technology that holds the potential to revolutionize drug delivery systems by enabling the creation of complex geometries and medications with tunable properties.

Recent progress in the 3D printing of microneedle patches for biomedical applications

3D-printed microneedles (MNs) have emerged as a transformative technology in drug delivery, diagnostics, and cosmetics, providing a minimally invasive alternative to traditional methods. This review highlights the advancements in 3D printing technologies, including fused deposition modeling (FDM), digital light processing (DLP), and stereolithography (SLA), which enable the precise fabrication of MNs with customizable geometries and functionalities. The unique ability of MNs to penetrate the stratum corneum facilitates enhanced delivery of therapeutic agents, biosensing capabilities, and improved patient compliance. Recent innovations in MNs design, such as biomimetic structures and optimized geometries, have significantly improved their mechanical properties and drug delivery efficiency. Furthermore, integrating sensing elements within MNs enables real-time monitoring of biomarkers, paving the way for personalized medicine. Despite the promising applications, challenges remain, including regulatory considerations, material biocompatibility, and manufacturing scalability. This review discusses the current state of 3D-printed MNs, their diverse applications, and future directions. By addressing existing limitations and exploring novel materials and hybrid fabrication techniques, 3D-printed MNs have the potential to revolutionize healthcare delivery and improve patient outcomes.

3D printing chronicles in medical devices and pharmaceuticals: tracing the evolution and historical milestones

The objective of this study is to collect the significant advancements of 3D printed medical devices in the biomedical area in recent years. Especially related to a range of diseases and the polymers employed in drug administration. To address the existing limitations and constraints associated with the method used for producing 3D printed medical devices, in order to optimize their suitability for degradation. The compilation and use of research papers, reports, and patents that are relevant to the key keywords are employed to improve comprehension. According to this thorough investigation, it can be inferred that the 3D Printing method, specifically Fuse Deposition Modeling (FDM), is the most suitable and convenient approach for preparing medical devices. This study provides an analysis and summary of the development trend of 3D printed implantable medical devices, focusing on the production process, materials specially the polymers, and typical items associated with 3D printing technology. This study offers a comprehensive examination of nanocarrier research and its corresponding discoveries. The FDM method, which is already facing significant challenges in terms of achieving optimal performance and cost reduction, will experience remarkable advantages from this highly valuable technology. The objective of this analysis is to showcase the efficacy and limitations of 3D-printing applications in medical devices through thorough research, highlighting the significant technological advancements it offers. This article provides a comprehensive overview of the most recent research and discoveries on 3D-printed medical devices, offering significant insights into their study.

Additive Manufacturing of SmartEx QD 100 Designed Oral Three-Dimensional Printlets Containing Isoniazid for Immediate Gastric Release by Selective Laser Sintering

The selection of appropriate materials and compatibility of selected materials with drugs and formulations are limiting steps in three-dimensional printing technology. In this study, SmartEx QD 100 (SM QD 100) was introduced as a novel, coprocessed, unexplored excipient that can be used in SLS-mediated 3D printing. The current study aimed to evaluate the feasibility of fabricating SM QD 100 containing INH-embedded SLS-mediated immediate gastric release tablets. The prepared physical mixtures were subjected to the fabrication of 3D printlets by using SLS-mediated 3D printing. The fabricated 3D printlets were subjected to physicochemical characterization by using various analytical techniques. After oral administration of sintered 3D printlets to rabbits, samples were collected and pharmacokinetic parameters were analyzed using the developed LC-APCI-MS/MS method. The optimized batch was able to release 100% INH within 15 min, which confirmed the immediate gastric release. Similarly, sintered 3D printlets were stable under accelerated stability conditions for three months. Finally, the pharmacokinetic parameters revealed the rate and extent of absorption of INH from sintered 3D printlets. As evidenced by in vitro and in vivo analyses, SM QD 100 was able to sinter SLS-mediated INH-embedded stable immediate gastric release tablets. SM QD 100 is a novel material for SLS-mediated 3D printing in pharmaceutical applications.

Application of 3D printing on the design and development of pharmaceutical oral dosage forms

3D printing technologies confer an unparalleled degree of control over the material distribution on the structures they produce, which has led them to become an extremely attractive research topic in pharmaceutical dosage form development, especially for the design of personalized treatments. With fine tuning in material selection and careful design, these technologies allow to tailor not only the amount of drug administered but the biopharmaceutical behaviour of the dosage forms as well. While fused deposition modelling (FDM) is still the most studied 3D printing technology in this area, others are gaining more relevance, which has led to many new and exciting dosage forms developed during 2022 and 2023. Considering that these technologies, in time, will join the current manufacturing methods and with the ever-increasing knowledge on this topic, our review aims to explore the advantages and limitations of 3D printing technologies employed in the design and development of pharmaceutical oral dosage forms, giving special focus to the most important aspects governing the resulting drug release profiles.

3D printed dispersible efavirenz tablets: A strategy for nasogastric administration in children

Enteral feeding tubes (EFTs) can be placed in children diagnosed with HIV which need nutritional support due to malnutrition. EFTs are the main route for medication administration in these patients, bringing up concerns about off label use of medicines, dose inaccuracy and tube clogging. Here we report for the first time the use of selective laser sintering (SLS) 3D printing to develop efavirenz (EFZ) dispersible printlets for patients with HIV that require EFT administration. Water soluble polymers Parteck® MXP and Kollidon® VA64 were used to obtain both 500 mg (P500 and K500) and 1000 mg printlets (P1000 and K1000) containing 200 mg of EFZ each. The use of SLS 3D printing obtained porous dosage forms with high drug content (20 % and 40 % w/w) and drug amorphization using both polymers. P500, K500 and K1000 printlets reached disintegration in under 230 s in 20 mL of water (25 ± 1 °C), whilst P1000 only partially disintegrated, possibly due to saturation of the polymer in the medium. As a result, the development of dispersible EFZ printlets using hydrophilic polymers can be explored as a potential strategy for drug delivery through EFTs in paediatrics with HIV, paving the way towards the exploration of more rapidly disintegrating polymers and excipients for SLS 3D printing.

Sketching feasibility of additively manufactured different size gradient conventional hollow capsular shells (HCSs) by selective laser sintering (SLS): From design to applications

Additive manufacturing (AM) is widely used to fabricate 3D printed objects from Computer-aided Design (CAD) prepared using the SolidWorks CAD modelling software. Different printing techniques are used to fabricate desired 3D objects; among all these techniques, it is widely accepted that SLS is one of the most effective methods of 3D printing for fabricating drug-loaded solid oral dosage forms (SODFs) in bulk quantities using the single-step process. Different SODFs, such as pills, miniprintlets, dual miniprintlets, and tablets, were fabricated with different sizes and shapes. In this study, for the first time, we introduce SLS-mediated hollow capsular shells (HCSs) with the help of the SLS 3D printing technique. This work aimed to explore the sinterability and feasibility of sketching HCSs using the SLS-mediated sintering technique with different marketed sizes of capsules ranging from 000 to 5. Here, we have utilized Kolliphor P 188 (KP 188) and Kollidon SR (KSR) in a 1:1 ratio as a matrix-forming agent and 1% charcoal as a laser absorption-enhancing material. In accordance with the CAD models, we have fabricated the gradient conventional different sizes of HCSs ranging from 000 to 5 using the constant printing parameters and composition. Fabricated all biobased HCSs were subjected to the assessment of mechanistic and physicochemical parameters using varied analytical tools. In the current study, tartrazine dye is used to assess the release pattern from HCSs, which resulted in the modified release pattern. The adapted approach will be the futuristic approach to replace animal-based gelatin capsules with pharmaceutical-grade polymer-based HCSs with a modified release with optimum mechanical strength.

Rising role of 3D-printing in delivery of therapeutics for infectious disease

Modern drug delivery to tackle infectious disease has drawn close to personalizing medicine for specific patient populations. Challenges include antibiotic-resistant infections, healthcare associated infections, and customizing treatments for local patient populations. Recently, 3D-printing has become a facilitator for the development of personalized pharmaceutic drug delivery systems. With a variety of manufacturing techniques, 3D-printing offers advantages in drug delivery development for controlled, fine-tuned release and platforms for different routes of administration. This review summarizes 3D-printing techniques in pharmaceutics and drug delivery focusing on treating infectious diseases, and discusses the influence of 3D-printing design considerations on drug delivery platforms targeting these diseases. Additionally, applications of 3D-printing in infectious diseases are summarized, with the goal to provide insight into how future delivery innovations may benefit from 3D-printing to address the global challenges in infectious disease.

In Vitro and In Vivo Characterization of the Transdermal Gel Formulation of Desloratadine for Prevention of Obesity and Metabolic Syndrome

Chronic use of antihistamines can induce abnormalities in lipid absorption with potential excessive accumulation of lipids in the mesentery that can lead to the development of obesity and a metabolic syndrome. The focus of the present work was to develop a transdermal gel formulation of desloratadine (DES) to prevent/reduce obesity and metabolic syndromes. Nine formulations were prepared to contain hydroxypropyl methylcellulose (2-3%), DES (2.5-5.0%), and Transcutol^® (15-20%). The formulations were evaluated for cohesive and adhesive properties, viscosity, drug diffusion through synthetic and pig ear skin, and pharmacokinetics in New Zealand white rabbits. Drug permeation was faster through the skin compared to synthetic membranes. The drug had good permeation, as indicated by very short lag time (0.08-0.47 h) and high flux (59.3-230.7 μg/cm².h). The maximum plasma concentration (C_max) and area under the curve (AUC) of transdermal gel formulations were 2.4 and 3.2 fold that of the Clarinex tablet formulation. In conclusion, as indicated by the higher bioavailability, transdermal gel formulation of DES may decrease the dose of the drug, compared to commercial formulation. It has the potential to reduce or eliminate metabolic syndromes associated with oral antihistamine therapy.

Pyrimethamine 3D printlets for pediatric toxoplasmosis: design, pharmacokinetics, and anti-toxoplasma activity

OBJECTIVES

The focus of the present research is to develop printlet formulations of pyrimethamine (PMT).

METHODS

Printlets formulation of PMT were developed by screening design by varying laser scanning speed, Kollidon® VA 64, polyvinylpyrrolidone, and disintegrant.

RESULTS

Laser scanning speed, Kollidon® VA, and disintegrant had statistically significant effect on hardness, disintegration time, and/or dissolution (p < 0.05). Dissolution was almost 100% in 30 min. X-ray powder diffraction indicated partial amorphous transformation of the crystalline drug. Pharmacokinetic and anti-toxoplasma activity profiles of the printlets and compressed tablets were superimposable with no statistical difference (p > 0.05).

CONCLUSION

Clinical performance of the printlets would be similar to the compressed tablets.

Raw Materials, Technology, Healthcare Applications, Patent Repository and Clinical Trials on 4D Printing Technology: An Updated Review

After the successful commercial exploitation of 3D printing technology, the advanced version of additive manufacturing, i.e., 4D printing, has been a new buzz in the technology-driven industries since 2013. It is a judicious combination of 3D printing technologies and smart materials (stimuli responsive), where time is the fourth dimension. Materials such as liquid crystal elastomer (LCE), shape memory polymers, alloys and composites exhibiting properties such as self-assembling and self-healing are used in the development/manufacturing of these products, which respond to external stimuli such as solvent, temperature, light, etc. The technologies being used are direct ink writing (DIW), fused filament fabrication (FFF), etc. It offers several advantages over 3D printing and has been exploited in different sectors such as healthcare, textiles, etc. Some remarkable applications of 4D printing technology in healthcare are self-adjusting stents, artificial muscle and drug delivery applications. Potential of applications call for further research into more responsive materials and technologies in this field. The given review is an attempt to collate all the information pertaining to techniques employed, raw materials, applications, clinical trials, recent patents and publications specific to healthcare products. The technology has also been evaluated in terms of regulatory perspectives. The data garnered is expected to make a strong contribution to the field of technology for human welfare and healthcare.

Releasing fast and slow: Non-destructive prediction of density and drug release from SLS 3D printed tablets using NIR spectroscopy

Selective laser sintering (SLS) 3D printing is a revolutionary 3D printing technology that has been found capable of creating drug products with varied release profiles by changing the laser scanning speed. Here, SLS 3D printed formulations (printlets) loaded with a narrow therapeutic index drug (theophylline) were produced using SLS 3D printing at varying laser scanning speeds (100-180 mm/s). The use of reflectance Fourier Transform - Near Infrared (FT-NIR) spectroscopy was evaluated as a non-destructive approach to predicting 3D printed tablet density and drug release at 2 h and 4 h. The printed drug products formulated with a higher laser speed exhibited an accelerated drug release and reduced density compared with the slower laser scanning speeds. Univariate calibration models were developed based on a baseline shift in the spectra in the third overtone region upon changing physical properties. For density prediction, the developed univariate model had high linearity (R² value = 0.9335) and accuracy (error < 0.029 mg/mm³). For drug release prediction at 2 h and 4 h, the developed univariate models demonstrated a linear correlation (R² values of 0.9383 and 0.9167, respectively) and accuracy (error < 4.4%). The predicted vs. actual dissolution profiles were found to be statistically similar (f₂ > 50) for all of the test printlets. Overall, this article demonstrates the feasibility of SLS 3D printing to produce drug products containing a narrow therapeutic index drug across a range of drug release profiles, as well as the potential for FT-NIR spectroscopy to predict the physical characteristics of SLS 3D printed drug products (drug release and density) as a non-destructive quality control method at the point-of-care.