Cyclosporine A eyedrops with self-nanoemulsifying drug delivery systems have improved physicochemical properties and efficacy against dry eye disease in a murine dry eye model

Triamcinolone-loaded self nano-emulsifying drug delivery systems for ocular use: An alternative to invasive ocular surgeries and injections

Inflammation of the posterior segment of the eye is a severe condition and hard to cure as delivery of drugs to the inflammation site is inefficient. Currently, the primary treatment approach is ocular surgery or invasive ocular injections. Herein, we designed and developed a topically self nano-emulsifying drug delivery system (SNEDDs) to deliver triamcinolone acetonide (TCA) to the posterior segment of the eye. A screening based on TCA solubility was conducted on each excipient followed by preparation of various formulations using different ratios of the selected excipients. Vesicles of optimized SNEDDs had less than 100 nm size and spherical morphology. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay showed self-emulsified vesicles have relatively high safety on retinal pigment epithelium (RPE) cell line. Furthermore, efficient cellular uptake of coumarin 6-loaded SNEDDs in RPE using confocal laser scanning microscopy (CLSM) was confirmed. In addition, an in-vivo study using hematoxylin and eosin (H&E) staining revealed that 14 days of topical treatment of albino rabbit eyes with TCA-loaded SNEDDs was safe and no sign of tissue destruction and inflammation was detected in different parts of the eye sections including cornea, sclera, retina, and optic nerve. Also, the CLSM images from topically treated eyes with coumarin 6 (a hydrophobic, fluorescent drug model) loaded SNEDDs, showed that the optimized SNEDDs could properly penetrate toward the posterior segments of the eye especially the retina, posterior parts of the choroid, and sclera. Considering the outstanding results obtained by ocular tissue penetration and low toxicity, prepared SNEDDs, have the potential to be used as a topical administration for treating posterior segment disorders of the eye through an utterly non-invasive route and TCA-loaded SNEDDs could be an alternative for TCA intravitreal and intra conjunctival injections.

3D printed capsule shells for personalized dosing of cyclosporine-loaded SNEDDS

Cyclosporine (CsA) is a potent immunosuppressant agent that has been used since 1980 for the treatment of various autoimmune diseases and is extensively used to enhance the survival rate of patients and grafts following organ transplant surgeries. CsA is a poorly soluble drug with a narrow therapeutic window and inter-subject variability, which can lead to graft rejection, nephrotoxicity and other severe adverse effects. This study explores a novel method that combines solubility enhancement of CsA using SNEDDS formulation and personalized dosage delivery using 3D printing technology. The oil phase was chosen as a combination of caproyl 90 and octanoic acid while the Smix phase was chosen as a combination of cremophore El and PEG 400. The optimized liquid SNEDDS was solidified using PEG 6000. An FDM printer was used to print a capsular shell with an oval base that ascends to form a dome with an opening at the top. This opening is used to fill the molten CsA-loaded SNEDDS formulation using a pipette or syringe. The CsA-loaded SNEDDS formulation was characterized by FTIR, DSC and SEM/EDX. The in-vitro release of CsA showed complete release within sixty minutes and followed Korsmeyer-Peppas release kinetics. The drug release was not affected by either the shell opening size or the amount of the loaded formulation. This novel method is simple and straightforward for personalized dosage delivery of drug-loaded SNEDDS formulations.

Overview of processed excipients in ocular drug delivery: Opportunities so far and bottlenecks

Ocular drug delivery presents a unique set of challenges owing to the complex anatomy and physiology of the eye. Processed excipients have emerged as crucial components in overcoming these challenges and improving the efficacy and safety of ocular drug delivery systems. This comprehensive overview examines the opportunities that processed excipients offer in enhancing drug delivery to the eye. By analyzing the current landscape, this review highlights the successful applications of processed excipients, such as micro- and nano-formulations, sustained-release systems, and targeted delivery strategies. Furthermore, this article delves into the bottlenecks that have impeded the widespread adoption of these excipients, including formulation stability, biocompatibility, regulatory constraints, and cost-effectiveness. Through a critical evaluation of existing research and industry practices, this review aims to provide insights into the potential avenues for innovation and development in ocular drug delivery, with a focus on addressing the existing challenges associated with processed excipients. This synthesis contributes to a deeper understanding of the promising role of processed excipients in improving ocular drug delivery systems and encourages further research and development in this rapidly evolving field.

Influence of filtering on the effective concentration and sterility of a 2% cyclosporine ophthalmic solution: a quality improvement perspective

BACKGROUND

Pharmaceutical companies do not sell formulations for all diseases; thus, healthcare workers have to treat some diseases by concocting in-hospital preparations. An example is the high-concentration 2% cyclosporine A (CyA) ophthalmic solution. Utilizing a filter in sterility operations is a general practice for concocting in-hospital preparations, as is the case for preparing a 2% CyA ophthalmic solution. However, whether filtering is appropriate concerning the active ingredient content and bacterial contamination according to the post-preparing quality control of a 2% CyA ophthalmic solution is yet to be verified.

METHODS

We conducted particle size, preparation concentration, and bacterial contamination studies to clarify aforementioned questions. First, we measured the particle size of CyA through a laser diffraction particle size distribution. Next, we measured the concentration after preparation with or without a 0.45-µm filter operation using an electrochemiluminescence immunoassay. Finally, bacterial contamination tests were conducted using an automated blood culture system to prepare a 2% CyA ophthalmic solution without a 0.45 μm filtering. Regarding the pore size of the filter in this study, it was set to 0.45 μm with reference to the book (the 6th edition) with recipes for the preparation of in-hospital preparations edited by the Japanese Society of Hospital Pharmacists.

RESULTS

CyA had various particle sizes; approximately 30% of the total particles exceeded 0.45 μm. The mean ± standard deviation of filtered and non-filtered CyA concentrations in ophthalmic solutions were 346.51 ± 170.76 and 499.74 ± 76.95ng/mL, respectively (p = 0.011). Regarding bacterial contamination tests, aerobes and anaerobes microorganisms were not detected in 14 days of culture.

CONCLUSIONS

Due to the results of this study, the concentration of CyA may be reduced by using a 0.45-µm filter during the preparation of CyA ophthalmic solutions, and furthermore that the use of a 0.45-µm filter may not contribute to sterility when preparing CyA ophthalmic solutions.

A randomized controlled trial involving college student: Comparing 0.15% hyaluronic acid with 0.05% cyclosporine A and 3% diquafosol sodium in the Treatment of Dry Eye

BACKGROUND

To compare the efficacy of 0.15% hyaluronic acid (HA), 0.05% cyclosporine A (CsA) and 3% diquafosol sodium (DQS) ophthalmic solution for the treatment of moderate-to-severe dry eye disease (DED) in college students and the effect on inflammatory factors in tears.

METHODS

This was a prospective, randomized, multicenter trial. A total of 282 college students diagnosed with moderate-to-severe DED between October 2, 2022 and March 1, 2023 were included. A total of 282 patients were randomized to treatment in the group of 0.15% HA or 0.05% CsA or 3% DQS in a 1:1:1 assignment. There was a main end point which is the variations in the corneal staining score to determine non-inferiority of 0.15% HA. Secondary target end points were ocular surface disease index score, Schirmer test, tear meniscus height and tear film breakup time. In addition, the inflammatory factor levels of Interleukin-1β, Interleukin-6, transforming growth factor-β1 in tears were measured. Effectiveness was assessed at baseline, 4- and 12-weeks.

RESULTS

In our analysis, the average change from baseline in corneal staining score confirmed non-inferiority of 0.15% HA to 0.05% CsA and 3% DQS and manifested obvious improvement of all groups as well (P < .05). Values for ocular surface disease index score, Schirmer test, tear meniscus height and tear film breakup time showed obvious improvements in all groups (P < .05), however, the difference intergroup was not statistically significant. Value for inflammatory factor was significant improvement across all groups, although inflammatory factor scores in the 0.05% CsA group showed a clear trend of better improvement at 12 weeks compared with 0.15% HA groups (P < .01). No serious adverse reactions were observed.

CONCLUSIONS

College students taking 0.15% HA had clinically and statistically significant improvement in corneal staining score and other indicators, but it was inferior to 0.05% CsA in anti-inflammatory therapy for moderate to severe DED. However, 0.15% HA is still an effective, safe and well-tolerated treatment option that may offer additional benefits in terms of convenience and compliance.

Recent Advances of Ocular Drug Delivery Systems: Prominence of Ocular Implants for Chronic Eye Diseases

Chronic ocular diseases can seriously impact the eyes and could potentially result in blindness or serious vision loss. According to the most recent data from the WHO, there are more than 2 billion visually impaired people in the world. Therefore, it is pivotal to develop more sophisticated, long-acting drug delivery systems/devices to treat chronic eye conditions. This review covers several drug delivery nanocarriers that can control chronic eye disorders non-invasively. However, most of the developed nanocarriers are still in preclinical or clinical stages. Long-acting drug delivery systems, such as inserts and implants, constitute the majority of the clinically used methods for the treatment of chronic eye diseases due to their steady state release, persistent therapeutic activity, and ability to bypass most ocular barriers. However, implants are considered invasive drug delivery technologies, especially those that are nonbiodegradable. Furthermore, in vitro characterization approaches, although useful, are limited in mimicking or truly representing the in vivo environment. This review focuses on long-acting drug delivery systems (LADDS), particularly implantable drug delivery systems (IDDS), their formulation, methods of characterization, and clinical application for the treatment of eye diseases.

Efficacy of Topical 0.05% Cyclosporine A for Ocular Surface Disease Related to Topical Anti-Glaucoma Medications

Purpose: We aimed to determine the therapeutic efficacy of 0.05% topical cyclosporine A (CsA) for chronic ocular surface disease (OSD) in patients using benzalkonium chloride (BAK)-preserved antiglaucoma eye drops. Methods: A prospective, randomized, paired-eye, controlled clinical trial was conducted with participants who had been instilling at least one BAK-preserved topical antiglaucoma drug in both eyes for at least 6 months. Topical CsA was only applied in randomly selected unilateral eyes. Visual field (VF) indices, ocular surface parameters, tear meniscus height (TMH), and matrix metalloproteinase-9 (MMP-9) immunoassay were evaluated at baseline and at 2 and 4 months. Results: Seventy eyes from 35 participants were included in the study. The Schirmer I, tear breakup time, and TMH increased by 4.5 ± 8.6 mm (P < 0.01), 5.0 ± 5.3 s (P < 0.001), and 85.4 ± 159.0 μm (P < 0.01) in the treated eyes at 4 months from baseline, respectively. The ocular staining score and MMP-9 positivity in the treated eyes decreased by 2.2 ± 1.3 (P < 0.001) and 0.7 ± 0.9 points (P < 0.001), respectively, at 4 months. In untreated eyes, only TMH increased by 41.4 ± 92.1 μm (P = 0.016) from baseline to 4 months. In VF indices, the tracking failure frequency was 19.09% ± 21.62%, and the test duration was 336.0 ± 79.5 s in the treated eyes at 4 months, which were lower than 34.37% ± 23.13% (P < 0.001) and 375.9 ± 70.7 s (P < 0.05) in the nontreated eyes. Conclusion: Application of topical 0.05% CsA significantly improved the OSD parameters and the reliability indices of VF tests. This study was registered with the Clinical Research Information Service (CRIS) (number KCT0007124).

Non-aqueous formulations in topical ocular drug delivery - a paradigm shift?

Topical eyedrop application is the preferred route for drug delivery to anterior segment tissues; however, the challenge of overcoming the eye's anatomical and physiological barriers while minimising tissue toxicity has restricted developments in this field. Aqueous vehicles have traditionally been used, which typically require several additives and preservatives to achieve physiologically compatible and sterile eyedrops, elevating their toxicity potential. Non-aqueous vehicles have been suggested as efficient alternatives for topical drug delivery as they can address many of the limitations associated with conventional aqueous eyedrops. However, despite their obvious advantages, non-aqueous eyedrops remain poorly researched and few non-aqueous formulations are currently available in the market. This review challenges the conventional hypothesis that aqueous solubility is a prerequisite to ocular drug absorption and establishes a rationale for using non-aqueous vehicles for ocular drug delivery. Recent advances in the field have been detailed and future research prospects have been explored, pointing towards a paradigm shift in eyedrop formulation in the near future.

A Review on Dry Eye Disease Treatment: Recent Progress, Diagnostics, and Future Perspectives

Dry eye disease is a multifactorial disorder of the eye and tear film with potential damage to the ocular surface. Various treatment approaches for this disorder aim to alleviate disease symptoms and restore the normal ophthalmic environment. The most widely used dosage form is eye drops of different drugs with 5% bioavailability. The use of contact lenses to deliver drugs increases bioavailability by up to 50%. Cyclosporin A is a hydrophobic drug loaded onto contact lenses to treat dry eye disease with significant improvement. The tear is a source of vital biomarkers for various systemic and ocular disorders. Several biomarkers related to dry eye disease have been identified. Contact lens sensing technology has become sufficiently advanced to detect specific biomarkers and predict disease conditions accurately. This review focuses on dry eye disease treatment with cyclosporin A-loaded contact lenses, contact lens biosensors for ocular biomarkers of dry eye disease, and the possibility of integrating sensors in therapeutic contact lenses.

Novel Treatments for Chronic Ocular Surface Pain

ABSTRACT

Several etiologies can contribute to ocular surface pain including nociceptive, peripheral neuropathic, and central neuropathic mechanisms. Clinical clues can help identify contributors to ocular surface pain in a patient. In individuals whose pain persists despite targeting nociceptive contributors, neuropathic mechanisms should be considered and addressed using oral, topical, and/or adjuvant agents.

Biomaterials for dry eye disease treatment: Current overview and future perspectives

Dry eye disease (DED) is an emerging health problem affecting millions of individuals every year. The current treatments for DED include lubricating eye drops and anti-inflammatory agents. These agents have to be used frequently and contain preservatives, which can damage the ocular surface. A substantially long-acting treatment with better bioavailability on the ocular surface might reduce the frequency of drug use and its side effects. This review summarizes the current state of different biomaterials-nanosystems, hydrogels, and contact lenses used as drug delivery systems in DED. The explored drugs in biomaterial formulation are cyclosporin, ocular lubricants, and topical steroids. Most of the data is from animal models where increased drug delivery and desired therapeutic effects could be obtained; however, trials involving human participants are yet to happen. There is no published study comparing the different types of biomaterials for DED use. Long-term studies evaluating their ocular toxicity and biocompatibility would enhance their transition to human use. Overall they look promising for DED treatment, but they are still in the stage of technological advancement and clinical studies.

Engineering Advanced Drug Delivery Systems for Dry Eye: A Review

Dry eye disease (DED) is a widespread and frequently reported multifactorial ocular disease that not only causes ocular discomfort but also damages the cornea and conjunctiva. At present, topical administration is the most common treatment modality for DED. Due to the existence of multiple biological barriers, instilled drugs generally exhibit short action times and poor penetration on the ocular surface. To resolve these issues, several advanced drug delivery systems have been proposed. This review discusses new dosage forms of drugs for the treatment of DED in terms of their characteristics and advantages. Innovative formulations that are currently available in the market and under clinical investigation are elaborated. Meanwhile, their deficiencies are discussed. It is envisioned that the flourishing of advanced drug delivery systems will lead to improved management of DED in the near future.

Instant Adhesion of Amyloid-like Nanofilms with Wet Surfaces

The adhesion and modification of wet surfaces by an interfacial adlayer remain a key challenge in chemistry and materials science. Herein, we report a transparent and biocompatible amyloid-like nanofilm that breaks through the hydration layer of a wet surface and achieves strong adhesion with a hydrogel/tissue surface within 2 s. This process is facilitated by fast amyloid-like protein aggregation at the air/water interface and the resultant exposure of hydrophobic groups. The resultant protein nanofilm adhered to a hydrogel surface presents an adhesion strength that is 20 times higher than the maximum friction force between the upper eyelid and eyeball. In addition, the nanofilm exhibits controllable tunability to encapsulate and release functional molecules without significant activity loss. As a result, therapeutic contact lenses (CLs) could be fabricated by adhering the functionalized nanofilm (carrying drug) on the CL surface. These therapeutic CLs display excellent therapeutic efficacy, showing an increase in cyclosporin A (CsA) bioavailability of at least 82% when compared to the commercial pharmacologic treatment for dry eye syndrome. Thus, this work underlines the finding that the bioinspired amyloid-like aggregation of proteins at interfaces drives instant adhesion onto a wet surface, enabling the active loading and controllable release of functional building blocks.

Ameliorative Potential of Resveratrol in Dry Eye Disease by Restoring Mitochondrial Function

Methods

The mitochondrial dysfunction of HCE-2 human corneal epithelial cells was induced by high osmotic pressure exposure and treated with resveratrol (50 μM). Western blotting was used to detect the expression of the antioxidant proteins SOD2, GPx, and SIRT1, and flow cytometry was used to detect cell apoptosis and ROS production. The DED mouse model was induced by 0.2% benzalkonium chloride (BAC) and treated with resveratrol. The tear yield was measured by the phenol cotton thread test, the density of cup cells in the conjunctiva was measured by periodic acid-Schiff (PAS) staining, and the expression levels of SIRT1, GPx, and SOD2 in lacrimal glands were detected by Western blotting.

Results

In hypertonic conditions, the apoptosis of HCE-2 cells increased, the expression of the antioxidant proteins SOD2 and GPx decreased, ROS production increased, and the expression of SIRT1 protein, an essential regulator of mitochondrial function, was downregulated. Treatment with resveratrol reversed the mitochondrial dysfunction mediated by high osmotic pressure. In the DED mouse model, resveratrol treatment promoted tear production and goblet cell number in DED mice, decreased corneal fluorescein staining, upregulated SIRT1 expression, and induced SOD2 and GPx expression in DED mice.

Conclusion

Resveratrol alleviates mitochondrial dysfunction by promoting SIRT1 expression, thus reducing ocular surface injury in mice with dry eye. This study suggests a new path against DED.

Current trends in pharmaceutical treatment of Dry Eye Disease: A review

Dry eye disease (DED), keratoconjunctivitis sicca or dysfunctional tear syndrome, is the most prevalent ophthalmic disease which affects a substantial segment of people worldwide with increasing frequency. It is considered a multifactorial disease of the ocular surface and tear film, characterized by a variation of signs and symptoms. The symptoms range from mild to severe itching, burning, irritation, eye fatigue, and ocular inflammation that may lead to potential damage to the cornea, conjunctiva and even vision loss. Correspondingly, depending on the different manifestations and pathophysiology, the treatment must be tailored specifically to each patient by targeting the specific mechanisms implicated in their disease. Currently, there are several medical products and techniques available or under investigation for the treatment of DED. The present article focused on the pathophysiology of DED, the new diagnostic approach and the recently developed drug delivery systems or devices reducing the progress of the disease and treating the causes.

Comparison of Consecutive Therapeutic Effects of Nanoemulsion and Emulsion Cyclosporin in Dry Eye Patients after Short-Term Treatment with Topical Fluorometholone

Purpose

To compare the consecutive therapeutic effects of 0.05% emulsion and nanoemulsion cyclosporine (CsA) in dry eye patients after short-term treatment with unpreserved 0.1% fluorometholone (FML).

Methods

A prospective, randomized, and double-blinded study of dry eye patients was conducted in a single center. Patients were assigned to the nanoemulsion CsA (group 1) and emulsion CsA (group 2) groups. To relieve discomfort, unpreserved 0.1% FML was used in both groups for 4 weeks and then changed to 0.05% CsA for the next 8 weeks. Symptom assessment in dry eye (SANDE) score, tear secretion, tear film breakup time (TBUT), corneal staining score (CSS), meibomian gland dysfunction (MGD) grade, and meibomian gland (MG) expression were evaluated at baseline and at 4 and 12 weeks after treatment.

Results

Twenty-four patients completed the treatment (9 and 15 patients in groups 1 and 2); in both the groups, SANDE score, TBUT, MGD grade, and MG expression were significantly improved after treatment with unpreserved 0.1% FML (each p < 0.005), and the therapeutic effects were enhanced with changes in nanoemulsion or emulsion CsA compared with baseline (each p < 0.001). TBUT and CSS after treatment in group 1 were significantly improved compared to those in group 2 (p=0.003 and 0.020, respectively).

Conclusion

Consecutive therapeutic effects of nanoemulsion or emulsion CsA after short-term treatment with unpreserved FML were excellent in patients with dry eyes. Topical nanoemulsion CsA showed better improvement in TBUT and OSS than CsA. This trial is registered with KCT0006070.

Recent Developments About the Pathogenesis of Dry Eye Disease: Based on Immune Inflammatory Mechanisms

Dry eye disease is a common and frequently occurring ophthalmology with complex and diverse causes, and its incidence is on the upward trend. The pathogenesis of DED is still completely clear. However, the immune response based on inflammation has been recognized as the core basis of this disease. In this review, we will systematically review the previous research on the treatment of DED in immune inflammation, analyze the latest views and research hotspots, and provide reference for the prevention and treatment of DED.

Isorhamnetin Ameliorates Dry Eye Disease via CFTR Activation in Mice

Dry eye disease is one of the most common diseases, with increasing prevalence in many countries, but treatment options are limited. Cystic fibrosis transmembrane conductance regulator (CFTR) is a major ion channel that facilitates fluid secretion in ocular surface epithelium and is a potential target of therapeutic agent for the treatment of dry eye disease. In this study, we performed a cell-based, high-throughput screening for the identification of novel natural products that activate CFTR and restore the aqueous deficiency in dry eye. Screening of 1000 natural products revealed isorhamnetin, a flavonol aglycone, as a novel CFTR activator. Electrophysiological studies showed that isorhamnetin significantly increased CFTR chloride current, both wild type and ∆F508-CFTR. Isorhamnetin did not alter intracellular cAMP levels and the activity of other ion channels, including ANO1, ENaC, and hERG. Notably, application of isorhamnetin on mouse ocular surface induced CFTR activation and increased tear volume. In addition, isorhamnetin significantly reduced ocular surface damage and expression of interleukin (IL)-1β, IL-8, and tumor necrosis factor (TNF)-α in an experimental mouse model of dry eye. These data suggest that isorhamnetin may be used to treat dry eye disease.

Improved Pharmacodynamic Potential of Rosuvastatin by Self-Nanoemulsifying Drug Delivery System: An in vitro and in vivo Evaluation

PURPOSE

The purpose of this proposed research was to investigate a nano-formulation developed using self-nanoemulsifying drug delivery system (SNEDDS) to improve the pharmacodynamic potential of rosuvastatin by assisting its transportation through lymphatic circulation.

METHODS

The utilized lipids, surfactants, and co-surfactants for SNEDDS were selected on the basis of solubility studies. The SNEDDS formulation was optimized by implementing a D-optimal mixture design, wherein the effect of concentration of Capmul MCM EP (X1), Tween 20 (X2) and Transcutol P (X3) as independent variables was studied on droplet size (Y1), % cumulative drug release (Y2) and self-emulsification time (Y3) as dependent variables. The optimized formulation was evaluated via in vitro parameters and in vivo pharmacodynamic potential in Wistar rats.

RESULTS

The D-optimal mixture design and subsequent ANOVA application resulted in the assortment of the optimized SNEDDS formulation that exhibited a droplet size of nano range (14.91nm), in vitro drug release of >90% within 30 minutes, and self-emulsification time of 16 seconds. The in vivo pharmacodynamic study carried out using Wistar rats confirmed the better antihyperlipidemic potential of developed formulation in normalizing the lipidic level of serum in contrast to pure drug and marketed tablets.

CONCLUSION

This research reports the application of D-optimal mixture design for successful and systematic development of rosuvastatin-loaded SNEDDS with distinctly enhanced in vitro and in vivo performance in comparison to marketed formulation. Eventually, improved anti-hyperlipidemic efficacy was envisaged which might be attributed to increased drug solubility and absorption. Overall, this study shows the utility of SNEDDS for improving the dissolution rate and bioavailability of poor aqueous-soluble drugs. The present SNEDDS formulation could be a promising approach and alternative to conventional dosage form.

Design and optimization of candesartan loaded self-nanoemulsifying drug delivery system for improving its dissolution rate and pharmacodynamic potential

During the last decades, much attention has been focused on SNEDDS approach to resolve concerns of BCS II class drugs with accentuation on upgrading the solubility and bioavailability. The present hypothesis confirms the theory that SNEDDS can reduce the impact of food on Candesartan solubilization, thereby offering the potential for improved oral delivery without co-administration with meals. The present studies describe quality-by-design-based development and characterization of Candesartan loaded SNEDDS for improving its pharmacodynamic potential. D-optimal mixture design was used for systematic optimization of SNEDDS, which showed globule size of 13.91 nm, more rapid drug release rate of >90% in 30 min and 16 s for self-emulsification. The optimized formulations were extensively evaluated, where an in vitro drug release study indicated up to 1.99- and 1.10-fold enhancement in dissolution rate from SNEDDS over pure drug and marketed tablet. In vivo pharmacodynamic investigation also showed superior antihypertensive potential of SNEDDS in normalizing serum lipid levels as compared to pure drug and marketed tablet that was executed on male Wistar rats. Overall, this paper reports successful systematic development of candesartan-loaded SNEDDS with distinctly improved biopharmaceutical performance. This research work interpreted a major role of SNEDDS for enhancing the rate of dissolution and bioavailability of poorly water soluble drugs.

A Review of the Mechanism of Action of Cyclosporine A: The Role of Cyclosporine A in Dry Eye Disease and Recent Formulation Developments

Dry eye disease (DED) is a multifactorial disease of the ocular surface and tear film that has gained awareness as a public health problem. Characteristics of DED include tear film instability, hyperosmolarity, and ocular surface inflammation, which can occur independently or may be a sequela of numerous ocular diseases, ocular surgery or contact lens wear. Much has been learned about the impact of the disease to help affected individuals who report symptoms of poor vision, pain, and tearing. Recently, new research highlights the importance of the role of ocular surface inflammation and damage in DED-leading to a vicious cycle of inflammation as well as loss of tear film homeostasis. DED immunopathophysiology is characterized by four stages: initiation, amplification, recruitment, and re-initiation. Cyclosporine is proven to be a valuable ophthalmic therapeutic for DED through its immunomodulatory actions and regulation of the adaptive immune response. Cyclosporine mechanism of action is well described in the published literature and the myriad of benefits in all four stages lend a broad-based immunomodulatory function particularly suitable for addressing DED. Furthermore, cyclosporine has unique goblet cell density improvement capabilities as well as anti-apoptotic properties. Topical formulations of cyclosporine are centered around addressing the highly lipophilic nature of the molecule. The poor aqueous solubility of cyclosporine traditionally presented technical challenges in drug delivery to the ocular surface. Newer formulations such as cationic emulsions and nanomicellar aqueous solutions address formulation, tissue concentration, and drug delivery challenges.