Apremilast loaded lyotropic liquid crystalline nanoparticles embedded hydrogel for improved permeation and skin retention: An effective approach for psoriasis treatment.

The present work aimed to prepare and evaluate Apremilast loaded lyotropic liquid crystalline nanoparticles (LCNPs) formulation for skin delivery to enhance the efficacy with reduced adverse effects of the oral therapy in psoriasis treatment. The LCNPs were prepared using the emulsification using a high shear homogenizer for size reduction and optimized with Box Behnken design to achieve desired particle size and entrapment efficiency. The selected LCNPs formulation was evaluated for in-vitro release, in-vitro psoriasis efficacy, skin retention, dermatokinetic, in-vivo skin retention, and skin irritation study. The selected formulation exhibited 173.25 ± 2.192 nm (polydispersity 0.273 ± 0.008) particle size and 75.028 ± 0.235% entrapment efficiency. The in-vitro drug release showed the prolonged-release for 18 h. The ex-vivo studies revealed that LCNPs formulation exhibited drug retention up to 3.2 and 11.9-fold higher, in stratum corneum and viable epidermis compared to conventional gel preparation. In-vitro cell line studies performed on immortal keratinocyte cells (HaCaT cells) demonstrated non-toxicity of selected excipients used in designed LCNPs. The dermatokinetic study revealed the AUC0-24 of the LCNPs loaded gel was 8.4 fold higher in epidermis and 2.06 fold in dermis, respectively compared to plain gel. Further, in-vivo animal studies showed enhanced skin permeation and retention of Apremilast compared to conventional gel.

Dermatokinetic assessment of luliconazole-loaded nanostructured lipid carriers (NLCs) for topical delivery: QbD-driven design, optimization, and in vitro and ex vivo evaluations.

The present study is concerned with the QbD-based design and development of luliconazole-loaded nanostructured lipid carriers (NLCs) hydrogel for enhanced skin retention and permeation. The NLCs formulation was optimized employing a 3-factor, 3-level Box-Behnken design. The effect of formulation variable lipid content, surfactant concentration, and sonication time was studied on particle size and % EE. The optimized formulation exhibited particle size of 86.480 ± 0.799 nm; 0.213 ± 0.004 PDI, ≥ - 10 mV zeta potential and 85.770 ± 0.503% EE. The in vitro release studies revealed sustained release of NLCs up to 42 h. The designed formulation showed desirable occlusivity, spreadability (0.748 ± 0.160), extrudability (3.130 ± 1.570), and the assay was found to be 99.520 ± 0.890%. The dermatokinetics assessment revealed the Cmax Skin to be ~ 2-fold higher and AUC0-24 to be ~ 3-fold higher in the epidermis and dermis of NLCs loaded gel in contrast with the marketed cream. The Tmax of both the formulations was found to be 6 h in the epidermis and dermis. The obtained results suggested that luliconazole NLCs can serve as a promising formulation to enhance luliconazole's antifungal activity and also in increasing patient compliance by reducing the frequency of application.

Bacterial biofilms associated skin disorders: Pathogenesis, advanced pharmacotherapy and nanotechnology-based drug delivery systems as a treatment approach.

BACKGROUND: Biofilms are microcolonies of microbes that form communities with a variety of microbes, exhibit the same gene composition but differ in gene expression. Biofilm-associated infections have been in existence for a long, however, biofilm-associated skin disorders have not been investigated much. OBJECTIVES: Biofilms, which are made mostly of the matrix can be thought of as communities of microbes that are more virulent and more difficult to eradicate as compared to their planktonic counterparts. Currently, several formulations are available in the market which have the potential to treat biofilm-assisted skin disorders. However, the existing pharmacotherapies are not competent enough to cure them effectively and entirely, in several cases. KEY FINDINGS: Especially with the rising resistance towards antibiotics, it has become particularly challenging to ameliorate these disorders completely. The new approaches are being used to combat biofilm-associated skin disorders, some of them being photodynamic therapy, nanotherapies, and the use of novel drug delivery systems. The focus of attention, however, is nanotherapy. Micelles, solid lipid nanoparticles, quatsomes, and many others are being considered to find a better solution for the biofilm-associated skin disorders. SIGNIFICANCE: This review is an attempt to give a perspective on these new approaches for treating bacterial biofilms associated with skin disorders.

Revisiting techniques to evaluate drug permeation through skin.

INTRODUCTION: Investigating the transportation of a drug molecule through various layers of skin and determining the amount of drug retention in skin layers is of prime importance in transdermal and topical drug delivery. The information regarding drug permeation and retention in skin layers aids in optimizing a formulation and provides insight into the therapeutic efficacy of a formulation. AREAS COVERED: This perspective covers various methods that have been explored to estimate drug/therapeutics in skin layers using in vitro, ex vivo, and in vivo conditions. In vitro methods such as diffusion techniques, ex vivo methods such as isolated perfused skin models and in vivo techniques including dermato-pharmacokinetics employing tape stripping, and microdialysis are discussed. Application of all techniques at various stages of formulation development where various local and systemic effects need to be considered. EXPERT OPINION: The void in the existing methodologies necessitates improvement in the field of dermatologic research. Standardization of protocols, experimental setups, regulatory guidelines, and further research provides information to select an alternative for human skin to perform skin permeation experiments to increase the reliability of data generated through the available techniques. There is a need to utilize multiple techniques for appropriate dermato-pharmacokinetics evaluation and formulation's efficacy.

Design and dermatokinetic evaluation of Apremilast loaded nanostructured lipid carriers embedded gel for topical delivery: A potential approach for improved permeation and prolong skin deposition.

The present study aimed to develop Apremilast loaded nanostructured lipid carriers (NLCs) for topical delivery to overcome the limitations of oral therapy and increase the efficacy. Apremilast loaded NLCs were prepared by hot emulsification technique. The developed formulation was optimized by Box Behnken design and characterized for size, entrapment efficiency, and zeta potential. The selected formulation was investigated for in-vitro release, ex-vivo skin retention, dermatokinetic, psoriasis efficacy, in-vivo skin retention and skin irritation study. The NLCs characterization results showed its spherical shape with the particle size of 157.91 ± 1.267 nm (0.165 ± 0.017 PDI). The entrapment efficiency and zeta potential were found to be 69.144 ± 0.278% and -16.75 ± 1.40 mV, respectively. The in-vitro release study revealed a controlled release of Apremilast from NLCs up to 24 h. The ex-vivo study showed 3-fold enhanced skin retention compared to conventional gel preparation. The formulation depicted improved psoriasis efficacy indicating reduced TNF-α mRNA expression. The cytotoxicity and skin irritation study revealed the prepared formulation has no toxicity or irritation. The study depicts the NLCs loaded Apremilast can be explored for the topical delivery for treatment of psoriasis with improved skin retention and efficacy.

Quality by design (QbD) in the formulation and optimization of liquid crystalline nanoparticles (LCNPs): A risk based industrial approach.

The intersection of lipid-based nanoparticles and lyotropic liquid crystals has provided a novel type of nanocarrier system known as 'lipid-based lyotropic liquid crystals' or 'liquid crystalline nanoparticles' (LCNPs). The unique advantages and immense popularity of LCNPs can be exploited in a better way if the formulation of LCNPs is done using the approach of quality by design (QbD). QbD is a systematic method that can be utilized in formulation development. When QbD is applied to LCNPs formulation, it will proffer many unique advantages, such as better product and process understanding, the flexibility of process within the design space, implementation of more effective and efficient control strategies, easy transfer from bench to bedside, and more robust product. In this work, the application of QbD in the formulation of LCNPs has been explored. The elements of QbD, viz. quality target product profile, critical quality attributes, critical material attributes, critical process parameters, quality risk management, design of experiments, and control strategy for the development of LCNPs have been explained in-depth with case studies. The present work will help the reader to understand the nitty-gritties in the application of QbD in the formulation of LCNPs, and provide a base for QbD-driven formulation of LCNPs with a regulatory perspective.

Chitosan-based microneedles as a potential platform for drug delivery through the skin: Trends and regulatory aspects.

Microneedles (MNs) fabrication using chitosan has gained significant interest due to its ability of film-forming, biodegradability, and biocompatibility, making it suitable for topical and transdermal drug delivery. The presence of amine and hydroxyl functional groups on chitosan permits the modification with tunable properties and functionalities. In this regard, chitosan is the preferred material for fabrication of MNs because it does not produce an immune response in the body and can be tailored as per required strength and functionalities. Therefore, many researchers have attempted to use chitosan as a drug delivery vehicle for hydrophilic drugs, peptides, and hormones. In 2020, the FDA has issued "Regulatory Considerations for Microneedling Products". This official guidance is a sign for future opportunities in the development of MNs. The present review focuses on properties, and modifications of chitosan used in the fabrication of MNs. The therapeutic and diagnostic applications of different types of chitosan-based MNs have been discussed. Further, the regulatory aspects of MN-based devices, and patents related to chitosan-based MNs are discussed.

Biodegradable microneedles fabricated with carbohydrates and proteins: Revolutionary approach for transdermal drug delivery.

There has been a surge in the use of transdermal drug delivery systems (TDDS) for the past few years. The market of TDDS is expected to reach USD 7.1 billion by 2023, from USD 5.7 billion in 2018, at a CAGR of 4.5%. Microneedles (MNs) are a novel class of TDDS with advantages of reduced pain, low infection risk, ease of application, controlled release of therapeutic agents, and enhanced bioavailability. Biodegradable MNs fabricated from natural polymers have become the center of attention among formulation scientists because of their recognized biodegradability, biocompatibility, ease of fabrication, and sustainable character. In this review, we summarize the various polysaccharides and polypeptide based biomaterials that are used to fabricate biodegradable MNs. Particular emphasis is given to cellulose and its derivatives, starch, and complex carbohydrate polymers such as alginates, chitosan, chondroitin sulfate, xanthan gum, pullulan, and hyaluronic acid. Additionally, novel protein-based polymers such as zein, collagen, gelatin, fish scale and silk fibroin (polyamino acid) biopolymers application in transdermal drug delivery have also been discussed. The current review will provide a unique perspective to the readers on the developments of biodegradable MNs composed of carbohydrates and protein polymers with their clinical applications and patent status.

QbD-driven formulation development and evaluation of topical hydrogel containing ketoconazole loaded cubosomes.

The proposed study aimed to develop topical hydrogel containing ketoconazole loaded cubosomes with lower surfactant concentrations using the 'Quality by Design' (QbD) approach. Risk assessment was performed, followed by screening and optimization of formulations by 32 factorial design using Design-Expert® software. Keeping the combination of constituents similar to that of the optimized batches as predicted post conduct of 'Design of Experiment' (DoE) studies, scale-up batches were prepared. The 32 factorial design model successfully predicted the composition of the optimized formulation within the confidence limits. In vitro drug release study was performed and analyzed by various mathematical models. Ex vivo permeation study was investigated using goat ear skin. These ketoconazole loaded cubosomes showed a release pattern similar to the Korsmeyer-Peppas model experiencing Fickian diffusion having 67% cumulative ketoconazole release within 24 h. Ex vivo permeation study of hydrogel containing ketoconazole loaded cubosomes revealed a sustained release pattern through the goat ear skin with around 92.73 % release within 24 h. Scale-up studies also gave the confirmatory results for the post characterization studies, whereby the particle size of ketoconazole loaded cubosomes was 198 nm with 45% ketoconazole entrapment efficiency. This hydrogel containing ketoconazole loaded cubosomes can be used for topical drug delivery.

Design of temozolomide-loaded proliposomes and lipid crystal nanoparticles with industrial feasible approaches: comparative assessment of drug loading, entrapment efficiency, and stability at plasma pH.

Temozolomide is a drug approved for treating glioblastomas, which has 100% oral bioavailability but gets degraded at physiological pH thus having very short half-life and only 20-30% brain bioavailability. Due to its amphiphilic nature, reported nanoformulations exhibits poor drug loading. The objective of this work was to formulate lipid-based drug delivery systems to enhance the brain bioavailability by prolonging the drug release and circulation time of the drug to overcome the limitations of the existing therapies and possible reduction of side effects. The size of the nanocarriers obtained was less than 300 nm and the PDI obtained was less than 0.3. The designed formulation showed higher entrapment efficiency as compared to the other reported nanocarriers of temozolomide. The designed formulations showed prolonged drug release from 12 to 20 h compared to 6 h for the pure drug. About 95% of the pure drug was degraded at plasma pH at the end of 12 h, whereas only 68% and 77% was degraded when entrapped inside the lipid crystal nanoparticles and proliposomes respectively. Further, pharmacokinetic and animal studies can confirm the potential of these for improvement of brain bioavailability.

Luliconazole loaded lyotropic liquid crystalline nanoparticles for topical delivery: QbD driven optimization, in-vitro characterization and dermatokinetic assessment.

Fungal infections are an important cause of morbidity and pose a serious health concern especially in immunocompromised patients. Luliconazole (LUL) is a topical imidazole antifungal drug with a broad spectrum of activity. To overcome the limitations of conventional dosage forms, LUL loaded lyotropic liquid crystalline nanoparticles (LCNP) were formulated and characterized using a three-factor, five-level Central Composite Design of Response Surface Methodology. LUL loaded LCNP showed particle size of 181 ± 12.3 nm with an entrapment efficiency of 91.49 ± 1.61 %. The LUL-LCNP dispersion in-vitro drug release showed extended release up to 54 h. Ex-vivo skin permeation studies revealed transdermal flux value (J) of LUL-LCNP gel (7.582 µg/h/cm2) 2 folds higher compared to marketed cream (3.3706 µg/h/cm2). The retention of LUL in the stratum corneum was ∼1.5 folds higher and ∼2 folds higher in the epidermis and other deeper layers in comparison to the marketed cream. The total amount of drug penetrated (AUC0-∞) with LCNP formulation was 4.7 folds higher in epidermis and 6.5 folds higher in dermis than marketed cream. The study's findings vouch that LCNP can be a promising and effective carrier system for the delivery of antifungal drugs with enhanced skin permeation.

Psoriasis: pathological mechanisms, current pharmacological therapies, and emerging drug delivery systems.

Psoriasis is a chronic autoimmune skin disorder triggered by either genetic factors, environmental factors, life style, or a combination thereof. Clinical investigations have identified pathogenesis, such as T cell and cytokine-mediated, genetic disposition, antimicrobial peptides, lipocalin-2, galectin-3, vaspin, fractalkine, and human neutrophil peptides in the progression of psoriasis. In addition to traditional therapies, newer therapeutics, including phosphodiesterase type 4 (PDE4) inhibitors, Janus kinase (JAK) inhibitors, monoclonal antibodies (mAbs), gene therapy, anti-T cell therapy, and phytoconstituents have been explored. In this review, we highlight nanotechnology-related developments for psoriasis treatment, including patented delivery systems and therapeutics currently in clinical trials.

Emerging Trends in Topical Delivery of Curcumin Through Lipid Nanocarriers: Effectiveness in Skin Disorders.

Curcumin is a unique molecule naturally obtained from rhizomes of Curcuma longa. Curcumin has been reported to act on diverse molecular targets like receptors, enzymes, and co-factors; regulate different cellular signaling pathways; and modulate gene expression. It suppresses expression of main inflammatory mediators like interleukins, tumor necrosis factor, and nuclear factor κB which are involved in the regulation of genes causing inflammation in most skin disorders. The topical delivery of curcumin seems to be more advantageous in providing a localized effect in skin diseases. However, its low aqueous solubility, poor skin permeation, and degradation hinder its application for commercial use despite its enormous potential. Lipid-based nanocarrier systems including liposomes, niosomes, solid lipid nanoparticles, nanostructured lipid carriers, lyotropic liquid crystal nanoparticles, lipospheres, and lipid nanocapsules have found potential as carriers to overcome the issues associated with conventional topical dosage forms. Nano-size, lipophilic nature, viscoelastic properties, and occlusive effect of lipid nanocarriers provide high drug loading, hydration of skin, stability, enhanced permeation through the stratum corneum, and slow release of curcumin in the targeted skin layers. This review particularly focuses on the application of lipid nanocarriers for the topical delivery of curcumin in the treatment of various skin diseases. Furthermore, preclinical studies and patents have also indicated the emerging commercialization potential of curcumin-loaded lipid nanocarriers for effective drug delivery in skin disorders. Graphical Abstract.

Insightful exploring of microRNAs in psoriasis and its targeted topical delivery.

Psoriasis is a common immune-mediated inflammatory skin disease. It includes multifaceted interaction between the immune system and the keratinocytes. Recent studies depicted the role of microRNAs (miRNAs) in hyperproliferation of keratinocytes and inflammatory cytokine production, which serve as biomarkers for diagnosis, monitoring treatment response, and prognosis. miRNAs are small nucleotide sequenced noncoding RNAs. Deregulation of miRNAs was found to be the most common factor in the studies pertaining to psoriasis. Hence, miRNA-based targeting for psoriasis treatment became the primary field of current research. miRNA due to its spatial and chemical properties offer different challenges in the process of its delivery. The topical delivery of different siRNAs and genes has paved a way to similar delivery of miRNA. The topical delivery of miRNAs to the skin can bring a revolutionary change in the field of psoriasis treatment.

Nanostructured Lipid Carriers as Potential Drug Delivery Systems for Skin Disorders.

BACKGROUND: Skin diseases affect all the age groups of people and have an impact on patients' physical, mental, and emotional status. Conventional topical preparation is limited with its efficacy due to low permeation, frequent application, and poor adherence to the therapy for prolong time. OBJECTIVE: The objective of this review article is to address the emerging trends of nanotechnology derived lipidic carrier systems for an effective treatment for skin disorders. METHODOLOGY: Various research and review articles from reputed international journals were referred and compiled. RESULTS AND DISCUSSION: Topical drug delivery systems were found to be more effective than oral and parenteral drug delivery systems for treating skin diseases due to targeted localized applications with reduced side effects. Lipid-based nanoparticles have been found to have the potential in treating skin diseases due to the biocompatibility and the versatility of the lipids. Nanostructured lipid carriers (NLCs) have gained much attention in treating skin diseases due to improved stability of the drugs, enhanced skin permeation, retention, and better therapeutic efficacy. The review summarizes the NLCs characteristics and their application for topical delivery of various therapeutics in skin disorders. NLCs have shown great potential in effective drug delivery for the treatment of psoriasis, dermatitis, bacterial infections, and skin cancer. Its cosmetic application has opened a new area for skincare. Furthermore, safety and clinical status revealed its future commercial acceptability. CONCLUSION: NLCs have been found as effective lipid nanocarriers for the delivery of topical therapeutics.

Emerging role of nanocarriers based topical delivery of anti-fungal agents in combating growing fungal infections.

The incidences of fungal infections have greatly increased over the past few years, particularly in humid and industrialized areas. The severity of such infections ranges from being asymptomatic-mild to potentially life-threatening systemic infections. There are limited classes of drugs that are approved for the treatment of such infections like polyenes, azoles, and echinocandins. Some fungi have developed resistance to these drugs. Therefore, to counter drug resistance, intensive large scale studies on novel targeting strategies and formulations are being conducted, which have gained impetus lately. Conventional formulations have limitations such as higher doses, frequent dosing, and several side effects. Such limiting factors have paved the path for the emergence of nanotechnology and its applications. This further gave formulation scientists the possibility of encapsulating the existing potential drug moieties into nanocarriers, which when loaded into gels or creams provided prolonged release and improved permeation, thus giving on-target effect. This review thus discusses the newer targeting strategies and the role of nanocarriers that could be administered topically for the treatment of various fungal infections. Furthermore, this approach opens newer avenues for continued and sustained research in pharmaceuticals with much more effective outcomes.

Curcumin loaded nanostructured lipid carriers for enhanced skin retained topical delivery: optimization, scale-up, in-vitro characterization and assessment of ex-vivo skin deposition.

Nanostructured lipid carriers (NLC) have become a promising drug delivery system for topical delivery of drugs. Delivery of lipophilic drugs with improved stability and entrapment efficiency is one of the foremost benefits of NLC based formulations. The objective of the present study was to improve the permeation of poorly soluble curcumin into topical skin layers for the treatment of chronic inflammatory disorder psoriasis and microbial mediated acne vulgaris. Hot emulsification followed by probe sonication method was employed for the preparation of the curcumin loaded NLC. Further, in-vitro and ex-vivo characterization was performed for designed NLC. The designed NLC showed a mean particle size 96.2 ± 0.9 nm, entrapment efficiency of 70.5 ± 1.65% and zeta potential of -15.2 ± 0.566 mV. Curcumin-NLC showed extended in-vitro release upto 48 hours, whereas free curcumin showed 100% drug release within 4 hours. Ex-vivo skin permeation studies revealed 3.24 fold improved permeation and skin retention in the case of curcumin loaded NLC gel compared to free curcumin gel. The cell viability studies demonstrated the formulation components showed no toxicity towards keratinocyte cells. In keratinocyte cells, improved cell uptake was observed for curcumin-NLC compared to free curcumin dispersion. The results suggested that the NLC based formulation had potential to improve the efficacy of curcumin.

Targeted drug-delivery systems in the treatment of rheumatoid arthritis: recent advancement and clinical status.

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that is characterized by synovial inflammation, cellular infiltration in joints which leads to progressive joint destruction and bone erosion. RA is associated with many comorbidities including pulmonary disease, rheumatoid nodules and can have a pessimistic impact on quality of life. The current therapies of RA treatment comprise conventional, small molecule and biological antirheumatic drugs. Their utility as therapeutic agents is limited because of poor absorption, rapid metabolism and adverse effects (dose-escalation, systemic toxicity, lack of selectivity and safety). To overcome these limitations, the novel drug delivery systems are being investigated. This review has compiled currently approved therapies along with emerging advanced drug-delivery systems for RA treatment. Further, active targeting of therapeutic agents to inflamed joints via folate receptor, CD44, angiogenesis, integrins and other provided an improved therapeutic efficacy in the treatment of RA.

UV spectrophotometric method for simultaneous estimation of betamethasone valerate and tazarotene with absorption factor method: Application for in-vitro and ex-vivo characterization of lipidic nanocarriers for topical delivery.

The present study elucidates the development of an accurate, precise and simple simultaneous estimation method for the routine analysis of Betamethasone Valerate (BV) and Tazarotene (TZ). This combination is widely used in the treatment of psoriasis. No method has been reported so far for the simultaneous estimation of BV and TZ in topical dosage forms. The method proposed by this study for the quantification of BV and TZ is the Absorption factor method. The developed method was validated as per the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) guideline. The validated method was found to be linear in a concentration range of 10-38 µg/mL and 4-14 µg/mL for BV and TZ respectively with a regression coefficient >0.990. The method was validated for accuracy and precision which revealed the recovery of >99.80% with RSD <2.0. The method was found to be precise with RSD <2% for inter and intraday. The developed method was employed for quantification of BV and TZ in lipid based nanocarriers formulation and their in-vitro drug release samples. Further, the developed method was successfully applied for the estimation of BV and TZ in the ex-vivo skin matrix. This showed that the method can sensitively determine the drugs in aqueous and biological samples.