Soluplus® polymeric nanomicelles improve solubility of BCS-class II drugs

Investigating in-vitro functionality and in-vivo taste assessment of eco-friendly Tadalafil Pastilles

Tadalafil (TDL) has poor bioavailability due to the less aqueous solubility and bitter taste. Oral solid dosage forms, especially tablets, have a broad market worldwide. Constraints of tablets are a long process, pollution, high processing cost, and requiring more excipient. The research was performed to optimize an eco-friendly immediate-acting pastille of TDL to put forward an alternate formulation to a tablet using advanced data mining tools. Another objective is to assess the taste masking of TDL using the Brief Access Taste Aversion (BATA) model. The amount of PEG-4000, Polyox N-10, and Kyron T-314 were chosen as critical material attributes from failure mode effect analysis. Box-Behnken design (BBD) was utilized to optimize the pastilles and ascertained the significant impact of chosen variables on disintegration time and % CDR at 10 min. The control strategy and optimal region were located using an overlay plot. The pastilles were able to release the drug within 15 min due to faster disintegration. The formulated pastilles were of uniform size, shape, and mechanical strength. The bitter taste of TDL was masked and confirmed by the BATA model. The newer formulation may be helpful in the industry due to its eco-friendly, single-step, and economical process. It unlocks a new direction in the field of oral solid dosage form as an alternative to tablets.

The Therapeutic Trip of Melatonin Eye Drops: From the Ocular Surface to the Retina

Melatonin is a ubiquitous molecule found in living organisms, ranging from bacteria to plants and mammals. It possesses various properties, partly due to its robust antioxidant nature and partly owed to its specific interaction with melatonin receptors present in almost all tissues. Melatonin regulates different physiological functions and contributes to the homeostasis of the entire organism. In the human eye, a small amount of melatonin is also present, produced by cells in the anterior segment and the posterior pole, including the retina. In the eye, melatonin may provide antioxidant protection along with regulating physiological functions of ocular tissues, including intraocular pressure (IOP). Therefore, it is conceivable that the exogenous topical administration of sufficiently high amounts of melatonin to the eye could be beneficial in several instances: for the treatment of eye pathologies like glaucoma, due to the IOP-lowering and neuroprotection effects of melatonin; for the prevention of other dysfunctions, such as dry eye and refractive defects (cataract and myopia) mainly due to its antioxidant properties; for diabetic retinopathy due to its metabolic influence and neuroprotective effects; for macular degeneration due to the antioxidant and neuroprotective properties; and for uveitis, mostly owing to anti-inflammatory and immunomodulatory properties. This paper reviews the scientific evidence supporting the use of melatonin in different ocular districts. Moreover, it provides data suggesting that the topical administration of melatonin as eye drops is a real possibility, utilizing nanotechnological formulations that could improve its solubility and permeation through the eye. This way, its distribution and concentration in different ocular tissues may support its pleiotropic therapeutic effects.

Dual stimuli-responsive polymeric nanoparticles combining soluplus and chitosan for enhanced breast cancer targeting

A dual stimuli-responsive nanocarrier was developed from smart biocompatible chitosan and soluplus graft copolymers. The copolymerization was investigated by differential scanning calorimetry (DSC), thermo-gravimetric analysis (TGA), and Fourier transform infrared (FTIR). The optimized chitosan-soluplus nanoparticles (CS-SP NPs) were further used for the encapsulation of a poorly water-soluble anticancer drug. Tamoxifen citrate (TC) was used as the model drug and it was loaded in CS-SP NPs. TC CS-SP NPs were characterized in terms of particle size, zeta potential, polydispersity, morphology, encapsulation efficiency, and physical stability. The nanoparticles showed homogenous spherical features with a size around 94 nm, a slightly positive zeta potential, and an encapsulation efficiency around 96.66%. Dynamic light scattering (DLS), in vitro drug release, and cytotoxicity confirmed that the created nano-system is smart and exhibits pH and temperature-responsive behavior. In vitro cellular uptake was evaluated by flow cytometry and confocal microscopy. The nanoparticles revealed a triggered increase in size upon reaching the lower critical solution temperature of SP, with 70% of drug release at acidic pH and 40 °C within the first hour and a 3.5-fold increase in cytotoxicity against MCF7 cells incubated at 40 °C. The cellular uptake study manifested that the prepared nanoparticles succeeded in delivering drug molecules to MCF7 and MDA-MB-231 cells. In summary, the distinctive characteristics provided by these novel CS-SP NPs result in a promising nano-platform for effective drug delivery in cancer treatment.

Gemcitabine-Vitamin E Prodrug-Loaded Micelles for Pancreatic Cancer Therapy

Pancreatic cancer (PC) is an aggressive cancer subtype presenting unmet clinical challenges. Conventional chemotherapy, which includes antimetabolite gemcitabine (GEM), is seriously undermined by a short half-life, its lack of targeting ability, and systemic toxicity. GEM incorporation in self-assembled nanosystems is still underexplored due to GEM's hydrophilicity which hinders efficient encapsulation. We hypothesized that vitamin E succinate-GEM prodrug (VES-GEM conjugate) combines hydrophobicity and multifunctionalities that can facilitate the development of Pluronic® F68 and Pluronic® F127 micelle-based nanocarriers, improving the therapeutic potential of GEM. Pluronic® F68/VES-GEM and Pluronic® F127/VES-GEM micelles covering a wide range of molar ratios were prepared by solvent evaporation applying different purification methods, and characterized regarding size, charge, polydispersity index, morphology, and encapsulation. Moreover, the effect of sonication and ultrasonication and the influence of a co-surfactant were explored together with drug release, stability, blood compatibility, efficacy against tumour cells, and cell uptake. The VES-GEM conjugate-loaded micelles showed acceptable size and high encapsulation efficiency (>95%) following an excipient reduction rationale. Pluronic® F127/VES-GEM micelles evidenced a superior VES-GEM release profile (cumulative release > 50%, pH = 7.4), stability, cell growth inhibition (<50% cell viability for 100 µM VES-GEM), blood compatibility, and extensive cell internalization, and therefore represent a promising approach to leveraging the efficacy and safety of GEM for PC-targeted therapies.

Prediction of enhanced drug solubility related to clathrate compositions and operating conditions: Machine learning study

Although complexation technique has been documented as a promising strategy to enhance the dissolution rate and bioavailability of water-insoluble drugs, prediction of the enhanced drug solubility related to clathrate compositions and operating conditions is still a challenge. Herein, clathrate compositions (drug content (DC), drug molecular weight (M) and molar ratio (Ratio)), operating conditions (drug concentration (C), pH, pressure (P), temperature (T) and dissolution time (t)) under the different excipients (PEG, PVP, HPMC and cyclodextrin) as main solubilizers of the clathrates condition as input parameters were used to predict two indexes (drug dissolved percentage and dissolution efficiency) simultaneously through machine learning methodfor the first time. The results show that PVP as the main solubilizer of clathrates had higher prediction accuracy to the drug dissolved percentage, and HPMC as the main solubilizer of clathrates had higher prediction accuracy to the drug dissolution efficiency. In addition, the influence of various factors and interactions on the target variables were analyzed. This study affords achievable hints to the quantitative prediction of the drug solubility affected by various compositions and different operating conditions.

Gout therapeutics and drug delivery

Gout is a common inflammatory arthritis caused by persistently elevated uric acid levels. With the improvement of people's living standards, the consumption of processed food and the widespread use of drugs that induce elevated uric acid, gout rates are increasing, seriously affecting the human quality of life, and becoming a burden to health systems worldwide. Since the pathological mechanism of gout has been elucidated, there are relatively effective drug treatments in clinical practice. However, due to (bio)pharmaceutical shortcomings of these drugs, such as poor chemical stability and limited ability to target the pathophysiological pathways, traditional drug treatment strategies show low efficacy and safety. In this scenario, drug delivery systems (DDS) design that overcome these drawbacks is urgently called for. In this review, we initially describe the pathological features, the therapeutic targets, and the drugs currently in clinical use and under investigation to treat gout. We also comprehensively summarize recent research efforts utilizing lipid, polymeric and inorganic carriers to develop advanced DDS for improved gout management and therapy.

Challenges and strategies for ocular posterior diseases therapy via non-invasive advanced drug delivery

Posterior segment diseases, such as age-related macular degeneration (AMD) and diabetic retinopathy (DR) are vital factor that seriously threatens human vision health and quality of life, the treatment of which poses a great challenge to ophthalmologists and ophthalmic scientists. In particular, ocular posterior drug delivery in a non-invasive manner is highly desired but still faces many difficulties such as rapid drug clearance, limited permeability and low drug accumulation at the target site. At present, many novel non-invasive topical ocular drug delivery systems are under development aiming to improve drug delivery efficiency and biocompatibility for better therapy of posterior segment oculopathy. The purpose of this review is to present the challenges in the noninvasive treatment of posterior segment diseases, and to propose strategies to tackle these bottlenecks. First of all, barriers to ocular administration were introduced based on ocular physiological structure and behavior, including analysis and discussion on the influence of ocular structures on noninvasive posterior segment delivery. Thereafter, various routes of posterior drug delivery, both invasive and noninvasive, were illustrated, along with the respective anatomical obstacles that need to be overcome. The widespread and risky application of invasive drug delivery, and the need to develop non-invasive local drug delivery with alternative to injectable therapy were described. Absorption routes through topical administration and strategies to enhance ocular posterior drug delivery were then discussed. As a follow-up, an up-to-date research advances in non-invasive delivery systems for the therapy of ocular fundus lesions were presented, including different nanocarriers, contact lenses, and several other carriers. In conclusion, it seems feasible and promising to treat posterior oculopathy via non-invasive local preparations or in combination with appropriate devices.

Review of industrially recognized polymers and manufacturing processes for amorphous solid dispersion based formulations

Evolving therapeutic landscape through combinatorial chemistry and high throughput screening have resulted in an increased number of poorly soluble drugs. Drug delivery strategies quickly adapted to convert these drugs into successful therapies. Amorphous solid dispersion (ASD) technology is widely employed as a drug delivery strategy by pharmaceutical industries to overcome the challenges associated with these poorly soluble drugs. The development of ASD formulation requires an understanding of polymers and manufacturing techniques. A review of US FDA-approved ASD-based products revealed that only a limited number of polymers and manufacturing technologies are employed by pharmaceutical industries. This review provides a comprehensive guide for the selection and overview of polymers and manufacturing technologies adopted by pharmaceutical industries for ASD formulation. The various employed polymers with their underlying mechanisms for solution-state and solid-state stability are discussed. ASD manufacturing techniques, primarily implemented by pharmaceutical industries for commercialization, are presented in Quality by Design (QbD) format. An overview of novel excipients and progress in manufacturing technologies are also discussed. This review provides insights to the researchers on the industrially accepted polymers and manufacturing technology for ASD formulation that has translated these challenging drugs into successful therapies.

Effect of hydrophilic polymers on the solubility and dissolution enhancement of rivaroxaban/beta-cyclodextrin inclusion complexes

BCS class II drugs exhibit low aqueous solubility and high permeability. Such drugs often have an incomplete or erratic absorption profile. This study aimed to predict the effects of β-cyclodextrin (βCD) and different hydrophilic polymers (poloxamer 188 (PXM-188), polyvinyl pyrrolidone (PVP) and soluplus (SOLO)) on the saturated solubility and dissolution profile of hydrophobic model drug rivaroxaban (RIV). Binary inclusion complex with βCD were prepared by kneading and solvent evaporation method, at drug to cyclodextrin weight molar ratios of 1:1, 1:2, and 1:4. Saturated solubility of the hydrophobic model moiety was evaluated with βCD to explore the increment in saturated solubility. Dissolution test was carried out to assess the drug release from the produced binary inclusion complex in the aqueous medium. Solid state analysis was performed using Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Scanning electron microscopy (SEM) techniques. When compared to pure drug, the binary complex (Drug: βCD at molar ratio of 1:2 w/w) demonstrated the best performance in terms of enhanced solubility and drug release. Furthermore, ternary inclusion complex was prepared with hydrophilic polymers SOLO, PVP K-30 and PXM-188 at 0.5%,1%,2.5%,5% and 10% w/w to optimized binary formulation RIV:βCD (1:2) prepared by kneading (KN) and solvent evaporation (S.E) method. The findings demonstrated that among ternary formulations (1:2 Drug: βCD: SOLO 10% S.E) manifested greatest improvement in saturated solubility and dissolution rate. Results of solubility enhancement and improvement in dissolution profile of model drug by ternary inclusion complexation were also supported by FTIR, DSC, XRD, and SEM analysis. So, it can be concluded that the ternary inclusion systems were more effective compared to the binary combinations in improving solubility as well as dissolution of hydrophobic model drug rivaroxaban.

Hot Melt Extrusion for Improving the Physicochemical Properties of Polydatin Derived from Polygoni cuspidati Extract; A Solution Recommended for Buccal Applications

Three different types of solid dispersions based on polyvinyl polymers and related copolymers (Kollidon® VA64, Soluplus® and Kollicoat IR®) comprising polydatin-rich Polygoni cuspidati extract were prepared by hot melt extrusion. The systems were characterized using X-ray powder diffraction, infrared spectroscopy as well as by polydatin release and in vitro permeability. Mucoadhesive tablets were prepared from the extrudates based on Kollidon® VA64 and Soluplus® to obtain a suitable pharmaceutical form, where (hydroxypropyl)methyl cellulose was added as a mucoadhesive agent. The tablets were evaluated in terms of the kinetics of polydatin release as well as their mucoadhesive properties. The best tabletability properties, polydatin release profile and adequate mucoadhesive properties were obtained by the formulation containing the Kollidon® VA64-based extrudate, which makes it an excellent prototype for enhancing the release of poorly water-soluble compounds.

Nanotechnology and narasin: a powerful combination against acne

Acne vulgaris is widely regarded as the most prevalent skin disorder characterized by painful, inflammatory skin lesions that are primarily attributed to the pathogenic actions of Cutibacterium acnes (C. acnes). To improve the clinical management of this disease, there is a pressing clinical demand to develop innovative antibacterial therapies that utilize novel mechanisms. The current research aimed to discover the antibacterial efficacy of narasin (NAR), a polyether ionophore, against drug-resistant acne bacteria. In addition, the study aimed to formulate self-nanomicellizing solid dispersions (SNMSD), utilizing Soluplus® (SOL), as a drug delivery system to incorporate NAR and selectively target the lipophilic C. acnes abundant environments within the skin. Furthermore, the study aimed to investigate the ex vivo deposition and permeation of NAR into the various layers of the skin using full-thickness porcine ear skin as a model skin. By encapsulating NAR within spherical polymeric micelles (dn < 80 nm) aqueous solubility was significantly increased by approximately 100-fold (from <40 μg mL-1 to 4600 μg mL-1). Following optimization, the micelle solution was integrated into a gel formulation (containing 0.2% w/v NAR) and evaluated for stability over 4 weeks at room temperature (drug content >98%). Results from drug deposition and permeation experiments demonstrated that the deposition of NAR from the NAR-micelle solution and its gel formulation into the lipophilic stratum corneum (19 835.60 ± 6237.89 ng cm-2 and 40 601.14 ± 3736.09 ng cm-2) and epidermis (19 347 ± 1912.98 ng cm-2 and 18 763.54 ± 580.77 ng cm-2) was superior to that of NAR in solution, which failed to penetrate any skin layers. In conclusion, the outcomes of this study provide evidence that NAR exhibits promising activity against antimicrobial resistant strains of C. acnes (MIC range ≤0.008-0.062) and that micelle nanocarriers can improve the aqueous solubility of poorly water-soluble drugs. Furthermore, our results highlight the ability of nanomicelles to enable selective and targeted drug delivery to the lipophilic skin layers.

Transdermal Delivery of Glimepiride: A Novel Approach Using Nanomicelle-Embedded Microneedles

Glimepiride (GM) is a hydrophobic drug that dissolves slowly and yields inconsistent clinical responses after oral administration. Transdermal drug delivery (TDD) is an appropriate alternative to oral administration. Microneedles (MNs) offer a promising delivery system that penetrates the skin, while polymeric micelles can enhance the solubility; hence, the combination of both results in high drug bioavailability. This study aims to improve glimepiride's solubility, dissolution rate, and bioavailability by incorporating nanomicelles into MNs for TDD. The nanomicelles formulated with 10% Soluplus® (SP) and 40% GM had a mean particle size of 82.6 ± 0.54, PDI of 0.1 ± 0.01, -16.2 ± 0.18 zeta potential, and achieved a 250-fold increase in solubility. The fabricated pyramid shaped GM-dissolving MNs were thermally stable and had no formulation incompatibility, as confirmed by thermal and FTIR analysis. The in vitro dissolution profile revealed that the GM release from nanomicelles and nanomicelle-loaded DMN was concentration-independent following non-Fickian transport mechanism. Improved pharmacokinetic parameters were obtained with dose of 240 µg as compared to 1 mg of GM oral tablet, in healthy human volunteers. The observed Cmax, Tmax and MRT were 1.56 μg/mL ± 0.06, 4 h, and 40.04 h ± 3.37, respectively. The safety profile assessment indicated that microneedles are safe with no adverse effects on skin or health. This study provides an alternative delivery system for the administration of glimepiride, resulting in improved bioavailability, enhanced patient compliance, and reduced dosing frequency.

Hybrid Dissolving Microneedle-Mediated Delivery of Ibuprofen: Solubilization, Fabrication, and Characterization

Microneedles have recently emerged as a promising platform for delivering therapeutic agents by disrupting the skin, resulting in improved and high drug delivery via this route. Ibuprofen is widely used topically and orally for chronic pain conditions; to avoid untoward gastric effects, topical application is preferred over the oral route. This study aimed to enhance the solubility of the poorly water-soluble ibuprofen using Soluplus (SP) as a solubilizer and to fabricate dissolving microneedle patches of the drug. The fabricated patches were compared with marketed oral and topical formulations of ibuprofen. A 432-fold increase was observed in the solubility of the drug at 8% SP. The FTIR studies revealed that the drug and polymers were compatible. MNs were of uniform morphology and released the drug in a predictable manner. The in vivo analysis on healthy human volunteers revealed a Cmax of 28.7 µg/mL ± 0.5 with a T_max of 24 h and a MRT of 19.5 h, which was significantly higher than that observed for commercially available topical formulations. The prepared ibuprofen microneedles have higher bioavailability and MRT at a lower dose (165 µg) as compared to tablet and cream doses (200 mg).

Maleic Acid as a Co-Former for Pharmaceutically Active GABA Derivatives: Mechanochemistry or Solvent Crystallization?

In this study, we compare the mechanochemical and classical solvent crystallization methods for forming maleates of GABA and its pharmaceutically active derivatives: Pregabalin, Gabapentin, Phenibut, and Baclofen. Common characterization techniques, like powder and single crystal X-ray diffraction, IR-spectroscopy, differential scanning calorimetry, thermogravimetric analysis and ¹H-NMR spectroscopy, are used for the evaluation of structural and physicochemical properties. Our work shows that maleate formation is possible with all investigated target compounds. Large increases in solubility can be achieved, especially for Pregabalin, where up to twentyfold higher solubility in its maleate compared to the pure form can be reached. We furthermore compare the mechanochemical and solvent crystallization regarding quickness, reliability of phase production, and overall product quality. A synthetic route is shown to have an impact on certain properties such as melting point or solubility of the same obtained products, e.g., for Gabapentin and Pregabalin, or lead to the formation of hydrates vs. anhydrous forms. For the GABA and Baclofen maleates, the method of crystallization is not important, and similarly, good results can be obtained by either route. In contrast, Phenibut maleate cannot be obtained pure and single-phase by either method. Our work aims to elucidate promising candidates for the multicomponent crystal formation of blockbuster GABA pharmaceuticals and highlight the usefulness of mechanochemical production routes.

Formulation of water-soluble Buddleja globosa Hope extracts and characterization of their antimicrobial properties against Pseudomonas aeruginosa

Buddleja globosa Hope (BG) extracts are traditionally used to treat skin and gastric ulcers due to their healing properties. Non-aqueous solvents such as ethanol and DMSO are usually used to extract naturally occurring compounds. However, the cytotoxicity of these solvents and the low water solubility of the extracted compounds can hinder their biomedical applications. To overcome the limited solubility of the BG extracts, we aimed to enhance the solubility by processing a standardized hydroalcoholic extract (BG-126) through spray drying (SD), with and without two solubility enhancers. Spray-dried BG (BG-SD) extracts and spray-dried BG extracts plus polyvinylpyrrolidone (BG-SD PVP) and Soluplus® (BG-SD SP) were developed starting from BG-126 (containing 53% ethanol). These four formulations were characterized by total phenolic content, water solubility at 25°C and 37°C, and antimicrobial properties against Pseudomonas aeruginosa. All the SD formulations presented a solubility that allowed them to reach maximum concentrations of 1,024 μg/ml catechin for BG-SD and 2,048 μg/ml catechin for BG-SD PVP and BG-SD SP for antimicrobial testing. BG-SD showed the highest antimicrobial potency with a minimum inhibitory concentration (MIC) of 512 μg/ml catechin, followed by BG-126 with a MIC of 1,024 μg/ml catechin and SP. BG-126 was also shown to inhibit biofilm formation, as well as the excipients PVP and SP. The spray-dried BG (BG-SD) extract represents a promising natural active component with enhanced antimicrobial properties against P. aeruginosa for further research and the development of novel phytopharmaceuticals.

Insights on Development Aspects of Polymeric Nanocarriers: The Translation from Bench to Clinic

Scientists are focusing immense attention on polymeric nanocarriers as a prominent delivery vehicle for several biomedical applications including diagnosis of diseases, delivery of therapeutic agents, peptides, proteins, genes, siRNA, and vaccines due to their exciting physicochemical characteristics which circumvent degradation of unstable drugs, reduce toxic side effects through controlled release, and improve bioavailability. Polymers-based nanocarriers offer numerous benefits for in vivo drug delivery such as biocompatibility, biodegradability, non-immunogenicity, active drug targeting via surface modification, and controlled release due to their pH—and thermosensitive characteristics. Despite their potential for medicinal use, regulatory approval has been achieved for just a few. In this review, we discuss the historical development of polymers starting from their initial design to their evolution as nanocarriers for therapeutic delivery of drugs, peptides, and genes. The review article also expresses the applications of polymeric nanocarriers in the pharmaceutical and medical industry with a special emphasis on oral, ocular, parenteral, and topical application of drugs, peptides, and genes over the last two decades. The review further examines the practical, regulatory, and clinical considerations of the polymeric nanocarriers, their safety issues, and directinos for future research.

Soluplus®-based dissolving microarray patches loaded with colchicine: towards a minimally invasive treatment and management of gout

Considered as one of the most common inflammatory arthritis, gout is characterised by a sudden onset of severe joint pain. As the first-line drug of choice used in treating acute gout, colchicine (CLC) is hindered by poor gastrointestinal permeability as well as unfavourable gastrointestinal side effects. Herein, we present, for the first time, the preparation of microarray array patches (MAPs) made of a polymeric solubiliser, Soluplus®, loaded with CLC for its systemic delivery. The fabricated MAPs displayed acceptable mechanical properties and were capable of being inserted into the skin to a depth of ≈500 μm in full thickness ex vivo neonatal porcine skin, as evidenced by optical coherence tomography. In vitro dermatokinetic studies utilising full thickness neonatal porcine skin demonstrated that the CLC-loaded MAPs delivered CLC across all skin strata, resulting in a delivery efficiency of 73% after 24 hours. Furthermore, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and cell proliferation assays along with LIVE/DEAD™ staining on the 3T3-L1 cell line showed that the MAP formulation displayed minimal toxicity, with acceptable biocompatibility. Lastly, the anti-inflammatory properties of the formulation were evaluated using a THP-1 macrophage cell line. It was shown that treatment of THP-1 macrophages that are exposed to lipopolysaccharide (LPS) with CLC-loaded MAPs caused a significant (p < 0.05) reduction of TNF-α production, a pro-inflammatory cytokine typically associated with the early onset of acute gout. Accordingly, CLC-loaded MAPs could represent a new minimally-invasive alternative strategy for management of acute gout.