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Topical ophthalmic drug product development is a niche research domain as the drug formulations need to be designed to perform in the unique ocular physiological conditions. The most common array of small molecule drug formulations intended for topical ophthalmic administration include solutions, suspensions, emulsions, gels, and ointments. The formulation components such as excipients and container closure are unique to serve the needs of topical ophthalmic delivery compared to other parenteral products. The selection of appropriate formulation platform, excipients, and container closure for delivery of drugs by topical ophthalmic route is influenced by a combination of factors like physicochemical properties of the drug molecule, intended dose, pharmacological indication as well as the market trends influenced by the patient population. In this review, data from literature and packaging inserts of 118 reference listed topical ophthalmic medications marketed in the US are collected and analyzed to identify trends that would serve as a guidance for topical ophthalmic formulation development for small molecule drugs. Specifically, the topics reviewed include current landscape of the available small molecule topical ophthalmic drug products in the US, physicochemical properties of the active pharmaceutical ingredients (APIs), formulation platforms, excipients, and container closure systems., Competing Interests: Declaration of Competing Interest Anand Ubhe, Heidi Oldenkamp, Ke Wu are employees of AbbVie and may own AbbVie stock. AbbVie sponsored and funded the study; contributed to the design; participated in the collection, analysis, and interpretation of data, and in writing, reviewing, and approval of the final publication., (Copyright © 2024 American Pharmacists Association. Published by Elsevier Inc. All rights reserved.)

Treatment of ocular diseases presents unique challenges and opportunities for the clinician and for the clinical pharmacologist. Ophthalmic pharmaceuticals, typically given as liquids, require consideration of solubility, physiological pH, and osmolarity, as well as sterility and stability, which in turn requires optimal pharmaceutics. Ocular tissue levels are challenging to obtain in humans, and the clinical pharmacokinetics is typically blood levels, which are primarily related to safety, rather than efficacy. The eye is a closed compartment with multiple physiological barriers with esterases and transporters, but relatively little cytochrome oxidases. Delivery routes include topical, intravitreal, and systemic. Patient dosing involves not only adherence issues common to all chronic diseases, but also performance requirements on eye drop instillation. Therapeutically, ocular diseases and their pharmacological treatments include both those analogous to systemic diseases (e.g., inflammation, infection, and neuronal degeneration) and those unique to the eye (e.g., cataract and myopia)., (© 2024, The American College of Clinical Pharmacology.)

As spaceflight becomes increasingly accessible and expansive to humanity, it is becoming ever more essential to consider the treatment of various eye diseases in these challenging environments. This paper delves into the increasing fascination with interplanetary travel and its implications for health management in varying environments. It specifically discusses the pharmacological management of ocular diseases, focusing on two key delivery methods: topical eye drops and intravitreal injections. The paper explores how microgravity impacts the administration of these treatments, a vital aspect in understanding drug delivery in space. An extensive analysis is presented on the pharmacokinetics of eye medications, examining the interaction between pharmaceuticals and ocular tissues in zero gravity. The goal of the paper is to bridge the understanding of fluid dynamics, microgravity and the human physiological systems to pave the way for innovative solutions faced by individuals in microgravity., Competing Interests: Declaration of competing interest None., (Copyright © 2024 The Committee on Space Research (COSPAR). Published by Elsevier B.V. All rights reserved.)

Medicated eye drops may have dual therapeutic and diagnostic uses that form part of the ophthalmic assessment paradigm. In this review article, commonly administered and prescribed eye drops were analyzed for their use as a diagnostic tool. It examines the common categories of eye drops-antimicrobial agents, topical anesthetics, mydriatics, and ocular anti-hypertensives, with respect to their therapeutic and diagnostic applications. Knowledge of the pharmacological effects of eye drops is an important aspect in performing clinical duties. Diagnostic tests by utilization of eye drops are safe, efficient, noninvasive, and informative to the eye care professional.

New, brand-name, ophthalmology drug products are developed, investigated, and submitted for marketing approval through premarket interactions with the Food and Drug Administration (FDA). These drug applications for novel drugs are reviewed by FDA for safety and effectiveness before being allowed on the market. Many brand-name drugs are allowed a period of marketing exclusivity and/or have patent protections that can delay generic competition. When these exclusivity periods or patents expire or are challenged (in the case of patents), generic competitors may then market equivalent products, as allowed by U.S. law (eg, Drug Price Competition and Patent Term Restoration Act, often referred to as "the Hatch-Waxman Act"). To be approved as a therapeutic equivalent, a generic product must demonstrate that it is both pharmaceutically equivalent and bioequivalent to the brand-name drug product, which can involve innovative analytical methods and study designs. To facilitate generic drug assessment and approval, the FDA has negotiated the Generic Drug User Fee Amendments (GDUFA) program that funds a rigorous generic drug development program that includes pre-Abbreviated New Drug Application (pre-ANDA) correspondence and meetings, targeted bioequivalence research, and publication of product-specific guidances (PSGs) to support generic drug research and development for manufacturers interested in developing generic drugs for the U.S. market. FDA's regulatory practices include the monitoring of quality and postapproval adverse events of all marketed products, including those for use in and around the eyes.

Ophthalmic diseases represent a significant problem as over 2 billion people worldwide suffer from vison impairment and blindness. Eye drops account for around 90% of ophthalmic medications but are limited in success due to poor patient compliance and low bioavailability. Low bioavailability can be attributed to short retention times in the eye caused by rapid tear turnover and the difficulty of drug diffusion through the multi-layered structure of the eye that includes lipid-rich endothelial and epithelial layers as well as the stroma which is high in water content. In addition, there are barriers such as tight junctional complexes in the corneal epithelium, lacrimal turnover, nasolacrimal drainage, blinking reflexes, efflux transporters, drug metabolism by ocular enzymes, and drug binding to or repulsion from conjunctival mucins, tear proteins, and melanin. In order to maximize transport through the cornea while minimizing drug loss through other pathways, researchers have developed numerous methods to improve eye drop formulations including the addition of viscosity enhancers, permeability enhancers, mucoadhesives, and vasoconstrictors, or using formulations that include puncta occlusion, nanocarriers, or prodrugs. This review explains the mechanism behind each of these methods, examines their history, analyzes previous and current research, evaluates future applications, and discusses the pros and cons of each technique.

Micelles have been studied in the targeting of drug substances to different tissues as a nano-sized delivery system for many years. Sustained drug release, ease of production, increased solubility, and bioavailability of drugs with low water solubility are the most important superiorites of micellar carriers. These advantages paved the way for the use of micelles as a drug delivery system in the ocular tissues. The unique anatomical structure of the eye as well as its natural barriers and physiology affect ocular bioavailability of the drugs negatively. Conventional dosage forms can only reach the anterior segment of the eye and are used for the treatment of diseases of this segment. In the treatment of posterior segment diseases, conventional dosage forms are administered sclerally, via an intravitreal injection, or systemically. However, ocular irritation, low patient compliance, and high side effects are also observed. Micellar ocular drug delivery systems have significant promise for the treatment of ocular diseases. The potential of micellar systems ocular drug delivery has been demonstrated by in vivo animal experiments and clinical studies, and they are continuing extensively. In this review, the recent research studies, in which the positive outcomes of micelles for ocular targeting of drugs for both anterior and posterior segment diseases as well as glaucoma has been demonstrated by in vitro , ex vivo , or in vivo studies, are highlighted.

Sufficient ophthalmic drug delivery is still challenging for pharmaceutical technologists, despite various scientific efforts. Several ocular drug carriers have been designed to enhance bioavailability by prolonging the drug retention time. One of the current encouraging approaches is the utilization of colloidal carriers with the characteristic submicron-nanometer size. Microemulsions (MEs) are such colloid systems that present sizes between 5 and 200 nm with significant thermodynamic stability and low surface tension. In addition, MEs as topical ocular carriers can lead to great ocular drug adsorption due to their enhanced retention time. Furthermore, considering that MEs are stable for long time and various temperatures, their ocular application is of great interest. The aim of this study is to cover basic physicochemical principals of ocular MEs such as their possible size, stability, and therapeutic efficacy against various eye disorders. Thus, a comprehensive review for ocular drug delivery systems in the form of MEs that show promising characteristics as their stability and therapeutic efficiency is performed.

Müller cells are specialized glial cells that span the entire retina from the vitreous cavity to the subretinal space. Their functional diversity and unique radial morphology render them particularly interesting targets for new therapeutic approaches. In this review, we reflect on various possibilities for selective Müller cell targeting and describe how some of their cellular mechanisms can be used for retinal neuroprotection. Intriguingly, cross-species investigation of their properties has revealed that Müller cells also have an essential role in retinal regeneration. Although many questions regarding this subject remain, it is clear that Müller cells have unique characteristics that make them suitable targets for the prevention and treatment of numerous retinal diseases., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: There has been a trend in the past five years in Jordan for ophthalmic anticholinergic preparations to be misused or abused. This is done mainly to experience mental altering effects such as mood changes, euphoria or hallucinations. Such products are mostly obtained from community pharmacies without a prescription., Objectives: This study aimed to observe the requests of ophthalmic preparations in community pharmacies in Amman, Jordan, and evaluating the most popular and frequently requested ophthalmic drops suspected of abuse. Also, it aimed to describe the current methods that Jordanian community pharmacists use to manage such requests., Methods: A prospective cross-sectional observational study was conducted between November 2016 and January 2017 at sixteen different community pharmacies in Amman. All ophthalmic products requested were observed during this period., Results: A total of 140 ophthalmic product requests for 130 customers were observed. Dry eye was the most common complaint for which the customer requested the medication (n = 30, 23.1%) and direct self-medication (ie-requesting the product by name), was the most frequent method of purchase (n = 63, 48.5%). In 19 cases (14.6%), product requests were suspected to be for non-medical (ie-abuse) purposes. Most of the suspected cases were for Pentolate ® (n = 11, 57.9%), whereas 7 were for Prisoline ® (36.8%) and 1 for Naphcon-A ® (5.3%). The majority of observed cases were for products requested without a prescription (n = 16, 84.2%), and in 12 cases out of which, sale was refused (63.2%)., Conclusion: More effort and enforcement of pharmacy regulation for safe dispensing is needed to reduce the abuse of ophthalmic products. Educating pharmacists and ophthalmologists would help raise awareness and control the type of drug abuse., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The eye consists of sensitive, compactly adjoined tissue structures which act as strong physical (static) and physiological (dynamic) barriers that prevent entry of foreign bodies into the eye. Together, these barriers reduce the bioavailability of topically and intraocularly administered medicaments thus demanding frequent drug administration for the treatment of chronic eye diseases. Hence, development of drug delivery systems (DDS) that can be retained in ocular tissues for longer durations can help to reduce the frequency of drug administration, whereas, delivery systems that traverse through ocular barriers may offer higher bioavailability of administered drugs to otherwise inaccessible ocular tissues. These objectives can be partially/fully achieved using nanoparticulate/colloidal DDS. Colloidal DDS, due to their nanodimensions, undergo internalization by cells which enables transport of drugs through ocular barriers. Furthermore, nanoparticles can prolong duration of drug release and can increase residence time of entrapped cargo molecules in ocular tissues. Together, these aspects facilitate a higher bioavailability, prolonged therapeutic effect and reduced frequency of drug administration for the effective treatment of chronic ocular diseases. Hence, nanocarriers have been widely explored for ophthalmic drug delivery applications. In this review, we discuss the anatomy of ocular tissues along with their barrier properties. We then discuss ocular diseases along with the various routes of drug administration and pathways of drug transport in the eye. The next section discusses the influence of physicochemical properties of therapeutic molecules on their ocular distribution and conventional and advanced (nanoparticulate/colloidal DDS) drug formulations that are used for the treatment of ocular diseases. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology., (© 2018 Wiley Periodicals, Inc.)

With the significant advances made in nanotechnology, research efforts focused on developing novel drug delivery platforms that can overcome the multitude of challenges encountered in ophthalmic drug delivery. Surface active agents (SAAs) have been extensively used for the formulation of many of the dosage forms targeting ocular tissues. Novel ophthalmic carriers utilizing SAAs were broadly classified into particulate, vesicular, and controlled release drug delivery systems. Depending on their physicochemical properties, SAAs can perform a variety of roles ranging from wetting agents, emulsifiers, stabilizers, charge inducers, solubilizers, antimicrobial agents, corneal permeation enhancers, and gelling agents. Nevertheless, their use is limited by their potential toxicity and possible interactions with other formulation ingredients. This review provides a comprehensive analysis of the different functional roles of SAAs in novel ophthalmic drug delivery platforms, their mechanism of action, and limitations that need to be considered during formulation to maximize their potential benefit. Understanding the mechanisms by which they perform their different roles and the possible interactions between SAAs and other formulation ingredients can help orientate the choice of formulators toward the SAA most suitable for the intended ocular application at a concentration that is both safe and effective., (Copyright © 2019 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

Developing suitable medicines for genetic diseases requires a detailed understanding of not only the pathways that cause the disease, but also the identification of the genetic components involved in disease manifestation. This article focuses on the complexities associated with ocular ciliopathies - a class of debilitating disorders of the eye caused by ciliary dysfunction. Ciliated cell types have been identified in both the anterior and posterior segments of the eye. Photoreceptors (rods and cones) are the most studied ciliated neurons in the retina, which is located in the posterior eye. The photoreceptors contain a specialized lightsensing outer segment, or cilium. Any defects in the development or maintenance of the outer segment can result in severe retinal ciliopathies, such as retinitis pigmentosa and Leber congenital amaurosis. A role of cilia in the cell types involved in regulating aqueous fluid outflow in the anterior segment of the eye has also been recognized. Defects in these cell types are frequently associated with some forms of glaucoma. Here, we will discuss the significance of understanding the genetic heterogeneity and the pathogenesis of ocular ciliopathies to develop suitable treatment strategies for these blinding disorders., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Purpose: The aim of the study was to assess the efficacy of a topical regenerating agent (RGTA) for management of persistent epithelial defects (PEDs) resistant to conventional therapy., Methods: Twenty-one patients (23 eyes) with PEDs despite the use of conventional therapy for lagophthalmos (n = 4), neurotrophic ulcer (n = 9), chemical burn (n = 3), Stevens-Johnson syndrome (n = 1), atopic keratoconjunctivitis (n = 1), severe dry eye (n = 2), peripheral ulcerative keratitis (n = 1), fungal keratitis (n = 1), and bacterial keratitis (n = 1) were enrolled in the study. Patients were treated with RGTA (Cacicol; Thea, Paris, France) instilled at a dosage of one drop on alternate days. Patients were evaluated by slit-lamp examination, anterior segment photography, and fluorescein-dye testing. Ulcer areas were noted on alternate days starting from the first day of instillation., Results: Twenty of 23 eyes (86.9%) displayed complete corneal healing after a mean period of ∼7.2 days (range, 2-20 days). Mean decrease ratio of ulcer area observed was 61.2% (range, 8.8%-100%, n = 19) on the 2nd day, 74.4% (range, 36%-100%, n = 16) on the 4th day, 80.2% (range, 43.7%-100%, n = 12) on the 6th day, 88.5% (range, 55.9%-100%, n = 9) on the 8th day, and 85.5% (range, 58.3%-100%, n = 7) on the 10th day. No significant differences were found in the epithelialization speed between eyes with and without bandage contact lenses in any postoperative day (P > 0.05). There were no treatment-related local or systemic side effects during the study., Conclusions: RGTA seems to be an effective therapeutic alternative in the treatment of persistent corneal epithelial defects.

The ophthalmic drug delivery is a challenge in the clinical treatment of ocular diseases. The traditional drug administration usually shows apparent limitations, such as the low bioavailability from the reason of low penetration of the cornea and the short survival time of drug in the eyes. To overcome these shortcomings, we propose an amphiphilic polymer micelle modified with hyaluronic acid (HA) for high efficient ophthalmic delivery of genistein, a widely used hydrophobic drug for treatment of ocular angiogenesis. The MPEG-b-PAE copolymer was synthesized by the Michael addition reaction, and the final drug carrier MPEG-b-PAE-g-HA was obtained by the process of esterification. Then, genistein was packaged in this drug carrier, getting the final micelles with size of about 84.5 nm. The cell viability tests showed that the micelles take no obvious cytotoxicity to the human cornea epithelium cells. The functionalities of drug slow release and cornea penetration ability were demonstrated in a series ex vivo experiments. Further, the vascular inhibition test illustrated that the micelles could significantly inhibit the angiogenesis of human umbilical vein endothelial cells. These results indicate that the constructed polymer has high feasibility to be used as drug carrier in the treatment of ocular diseases.

Purpose: To compare the success rates of eye drop instillation in the sitting position and supine position among Japanese patients with ocular diseases (cataract, glaucoma, or retinal and vitreous diseases)., Methods: Patients who were hospitalized in Okayama University Hospital for eye surgery were studied. Instillation procedures of each patient in both the sitting and supine positions were recorded using a video camera at the time of instillation. We defined "success" when one drop fell accurately onto the ocular surface at the first attempt. Instillation of two or more drops, drops delivered to a site other than the eye surface, and touching the eyelashes, eyelids, or conjunctiva with the tip of the eye drop bottle were regarded as "failure". We excluded patients with vision below counting finger., Results: One-hundred and two patients (54 males and 58 females, aged 70.2 ± 12.3 years) with ocular disease who were hospitalized for surgery (cataract: 61.8%, glaucoma: 15.7%, retinal and vitreous diseases: 22.5%) were included in this prospective observational study. The mean duration of eye drop use was 3.1 ± 5.2 years. The success rate of eye drop instillation was significantly higher in the supine position than in the sitting position (64.7% vs. 50%, P = 0.0039). The mean age was significantly higher in the failure group than in the success group (74.0 ± 11.5 vs. 67.7 ± 12.4 years, P = 0.0085) for the sitting position, but not significantly different for the supine position (72.3 ± 12.9 vs. 70.1 ± 12.0 years, P = 0.3849). No significant differences in mean duration of drop use, mean corrected VA, and mean spherical equivalent refraction were observed between success and failure groups, for both sitting and supine positions., Conclusions: In the present study, the success rate of eye drop instillation was significantly higher when applied in the supine position than in the sitting position., Competing Interests: The authors have declared that no competing interests exist.

Aim: Nanostructured lipid carriers in-gel (NLCs-gel) were prepared to enhance and improve the ocular delivery of dexamethasone. Materials & methods: NLCs containing dexamethasone prepared by high-pressure homogenization were characterized and dispersed into thermosensitive gels (Pluronic F127 and F68 as gels material). In vitro drug release studies, ocular irritation tests, ex vivo corneal penetration and drug dynamics of NLCs and NLCs-gel were evaluated in aqueous humor., Results: NLCs-gel exhibited a rapid sol-gel transition at 34.4°C and presented nano-sized, narrowly distributed particles. Corneal penetration studies revealed steady sustained drug release (Ritger-Peppas); NLCs-gel increased ocular bioavailability by prolonging precorneal retention time and improving corneal permeation., Conclusion: These findings suggest developing NLCs-gel for potential treatment of posterior segment eye diseases.

Purpose: To determine the ocular toxicity, systemic exposure, and amounts of dexamethasone sodium phosphate (DSP) in ocular tissues after administration of DSP with the Visulex system (DSP-Visulex)., Methods: DSP-Visulex was applied onto healthy rabbit eyes. DSP concentrations (4%, 8%, 15%, and 25%) and treatment durations (5, 10, and 20 min) were evaluated for the amounts of DSP in the ocular tissues and in plasma after single administrations of DSP-Visulex. The drug in eye tissues and plasma was analyzed by high-performance liquid chromatography-UV/VIS and by liquid chromatography-mass spectrometry, respectively. The safety and tolerability were ascertained based on clinical observations and histopathological examinations from repeat weekly DSP-Visulex treatments (4%, 8%, 15%, and 25% for 20 min) for 12 weeks., Results: Significant amounts of DSP (ie, higher than 1 μg/g) were found in the anterior chamber, retina-choroid, cornea, vitreous, conjunctiva, and sclera after single applications of DSP-Visulex. The DSP concentrations in the ocular tissues and in plasma increased with increased DSP concentrations in the Visulex applicator and with increased application times. Systemic DSP was rapidly detected. The plasma half-life was 2-3 h. C max was 148 and 1,844 ng/mL, and the area under the plasma drug concentration versus time curve (AUC) was 418 and 3,779 ng · h/mL for the low dose (4% DSP-Visulex for 5 min) and the high dose (15% DSP-Visulex for 20 min), respectively. Ocular findings over 12 weeks were mostly conjunctival injection and eye discharge. These were transient and mild. Histopathological examinations indicated the eyes to be normal., Conclusions: DSP can be administered safely and effectively into the rabbit eye with the Visulex system. Treatment duration and DSP concentration are important factors in achieving therapeutic levels. Repeat applications of DSP-Visulex are safe and well tolerated for weekly administrations over 4-12 weeks. DSP-Visulex has clinical potential for the noninvasive treatment of ocular diseases.

Purpose: The purpose of this study was to develop and evaluate a novel dexamethasone- and tobramycin-loaded microemulsion for its potential for treating anterior segment eye infections., Methods: The microemulsion was evaluated for pH, particle size, zeta potential, light transmittance, morphology, and in vitro drug release. Sterility of the microemulsion was evaluated by direct as well as plate inoculation methods. Anti-inflammatory activity of dexamethasone, bactericidal activity of tobramycin, and cytotoxicity of the microemulsion were assessed and compared to that of the marketed eye drop suspension (Tobradex ® ). Histological evaluation was performed in bovine corneas to assess the safety of microemulsion in comparison to Tobradex suspension. In addition, the stability of the microemulsion was studied at 4°C, 25°C, and 40°C., Results: The pH of the microemulsion was close to the pH of tear fluid. The microemulsion displayed an average globule size under 20 nm, with light transmittance around 95%-100%. The aseptically prepared microemulsion remained sterile for up to 14 days. The cytotoxicity of the microemulsion in bovine corneal endothelial cells was comparable to that of the Tobradex suspension. The anti-inflammatory activity of dexamethasone and the antibacterial activity of tobramycin from the microemulsion were significantly higher than those of the Tobradex suspension (P < 0.05). Histological evaluation showed an intact corneal epithelium without any signs of toxicity, and the developed microemulsion was found to be stable at 4°C and 25°C for 3 months., Conclusion: In conclusion, the developed microemulsion could be explored as a suitable alternative to the marketed suspension for treating anterior segment eye infections.

Ocular cystinosis is a rare disease characterised by the deposit of cystine crystals on the corneal surface, which hinder patients' eyesight. Oral cysteamine is given as cysteamine; however, it does not reach the cornea due to the lack of corneal vascularization making necessary its  administration by the topical ocular route. The aim of the present study is to  determine the stability of an ophthalmic hydrogel of cysteamine, which can be  potentially prepared at hospital pharmacy departments, under different preservation conditions during a follow-up of 30 days. Different physical  and chemical parameters were evaluated: osmolality, pH and  cysteamine concentration, which has been measured by a method of ultra  performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS).  Descriptive assays were also performed, such as transparency measurement and  microbiological assays in order to verify its sterility. The obtained results  allow us to conclude that the cysteamine hydrogel is stable during 30 days,  being recommendable its preservation in refrigerated conditions., (Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.)

Local ocular delivery of cyclosporine A (CsA) is the preferred method for CsA delivery as a treatment for ocular inflammatory diseases such as uveitis, corneal healing, vernal keratoconjunctivitis and dry eye disease. However, due to the large molecular weight and hydrophobic nature of CsA and the natural protective mechanisms of the eye, achieving therapeutic levels of CsA in ocular tissues can be difficult. This review gives a comprehensive overview of the current products available to clinicians as well as emerging drug delivery solutions that have been developed at both the academic and industry levels., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

Objective: To assess medical practices surrounding the use of topical ocular cyclosporine A across European Union nations., Methods: Key stakeholders (ophthalmologists, hospital pharmacists, regulatory health authorities) from European Union member states were interviewed by telephone using a semi-structured, open-ended questionnaire. Ophthalmologists responded to questions about practice patterns of cyclosporine A use (prescription frequency, indication, dosage), pharmacists about cyclosporine A formulations (composition, manufacturing process, quality control, distribution), and the regulatory authorities about market authorization and pharmacovigilance for various cyclosporine A products., Results: Over the years, cyclosporine A use for ophthalmic indications has increased across all European Union nations. Prevalence of cyclosporine A use was heterogeneous, with Belgium, France, Germany, Italy, Portugal, Spain and the United Kingdom reporting the highest frequency. Compounded cyclosporine A formulations and other cyclosporine A products were prescribed through temporary authorization on a compassionate use or named-patient basis. Cyclosporine A was prescribed for dry eye disease, atopic and vernal keratoconjunctivitis, corneal graft rejection, and other autoimmune and inflammatory diseases. Concentrations of prescribed topical cyclosporine A ranged between 0.05-2% and formulations were instilled 1-6 times daily. Interviewed stakeholders expressed concern regarding, (1) paucity of product information, (2) lack of standardized manufacturing processes and quality control of cyclosporine A formulations, and (3) poor regulation and pharmacovigilance of ocular cyclosporine A-based products., Conclusions: Medical practice surrounding ocular cyclosporine A use in European Union nations differs based on variations in concentration, dosage, prescription indication, formulation, availability and distribution, manufacturing, quality, and regulatory monitoring., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Objective: To evaluate the compatibility of commercially available eye drop surface tension with the tear film physiological range and to characterize commonly used ophthalmic excipients in terms of their surface activity under eye-biorelevant conditions., Significance: There are a number of quality requirements for the eye drops (e.g. tonicity, pH, viscosity, refractive index) that needs to comply with the physiological parameters of the eye surface. However, the adjustment of surface tension properties of the eye drops to the normal range of surface tension at the air/tear fluid interface (40-46 mN/m) has received rather less attention thus far. Yet, the surface tension at the air/tear fluid interface is of vital importance for the normal function of the eye surface., Methods: The surface tension compatibility of the isotonic aqueous solutions of commonly used ophthalmic excipients as well as 18 approved eye drops with the tear fluid have been evaluated using surface tension method., Results: Each ophthalmic ingredient including the preservatives, solubilizing agents and thickening agents can influence the surface tension of the final formulation. In case of complex ophthalmic formulations one should also consider the possible interactions among excipients and consequent impact on overall surface activity. Out of 18 evaluated eye drops, three samples were within, 12 samples were below and three samples were above the physiological range of the tear fluid surface tension., Conclusions: Our results provide a rationale for clinical studies aiming to assess the correlation between the eye drops surface tension and the tear film (in)stability.

Ocular involvement of chronic graft-versus-host disease (cGVHD) is a complication that occurs in up to 60% of patients after allogeneic hematopoietic stem cell transplantation. Conventional therapeutic options include medical and surgical procedures that are administered depending on the severity of the condition, but most of them have provided unsatisfactory results and, to date, there is no consensus about treatment. We considered that topical application of a platelet lysate, administered as eye drops, might be considered an alternative worthwhile of investigation to treat ocular surface disorders in patients suffering from cGVHD. Therefore, we conducted a single-center prospective pilot study to assess the efficacy and safety of using eye drops made from reconstituted lysed platelet concentrate. Twenty-six patients with ocular cGVHD were eligible for the study; all but 2 completed their scheduled 1-year treatment and complied with the hematologic and ophthalmic regimen. At their first assessment interviews, after 30 days of treatment, 91% of patients reported an improvement in their symptoms and for 32%, substantive objective differences were measured. Remission of corneal damage was seen for 86% of our cohort, and improved National Institutes of Health scores for 73%, of whom 8% achieved the best score of 0 (ie, non-dry eye). Similar results were seen at later time points. Comparing outcomes for our patient cohort to those determined retrospectively for patients in our institutional database revealed a 5-year overall survival (OS) of 65%. This OS is comparable to patients with limited cGVHD (75%) and is superior to that of patients with nonocular extensive cGVHD or without cGVHD (30% and 59%, respectively) (P = .013). Our results suggest that platelet-derived eye drops are a safe, practical, and well-tolerated therapeutic option that offers substantial benefits for most patients affected by ocular cGVHD at onset. The favorable OS of our patient cohort suggests that this topical therapy, rather than systemic immunosuppression, may be the treatment of choice., (Copyright © 2016 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.)

This review highlights the current state of knowledge of in vivo testing of drug-delivering contact lenses. There has been a significant increase in interest in alternative means to deliver ocular pharmaceuticals, and within the past few decades, contact lenses have emerged as a vehicle of interest because of their biocompatibility and acceptance by both eye care professionals and the public. Using techniques such as molecular imprinting, vitamin E diffusion barriers, ionic reservoirs, and drug-impregnated films, significantly improved drug release kinetics have been observed in vitro. Extension of these results into in vivo studies has thus far been limited but has led to evidence of the viability of this drug delivery platform by demonstrating improved drug residence time, drug penetration, and clinical outcomes when compared with conventional therapy such as eye drops. The evidence supporting these improvements has occurred in both animal models and small human trials and is presented within this review.

The purpose of each dosage form is to provide an optimal therapeutic effect with a minimum dose and with minimal side effects. This is particularly relevant for drugs that require systemic administration, higher dosing and/or show lower bioavailability. Тhe eye as an anatomical structure is an extremely protected organ. In this regard, providing an optimal bioavailability in the eye tissues, resulting in the desired therapeutic effect represents a major challenge. This is especially true for the treatment of diseases, affecting the posterior segment after topically administered drug formulations. The use of nano- and microcarriers of drug substances may be an appropriate technological approach, to provide a high bioavailability of the drug substance for a certain interval of time at the right place. The purpose of this review is to indicate how nano- and microcarriers of drug substances can solve the problems with the drug delivery in the ocular tissues, to indicate the possible hazards and side effects, depending on the polymer nature and route of administration, and to visualize the future potential of these carriers in the pharmaceutical practice., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

The ocular delivery of drugs encounters several limitations because of the dynamic and static barriers of the human's eye anatomy and physiology. The poor bioavailability of drugs are mainly related to the topical administration, i.e. eye drops which is the most common drug dosage form for the treatment of eye pathologies. Precorneal factors and drug limitations related to its solubility and susceptibility for physicochemical degradation could be the main reasons for the poor permeation and uptake in the ocular mucosa. Pathologies affecting the anterior and posterior segment of the eye are thereafter difficult to be treated and, given the chronic and degenerative nature of some of these injuries, it is crucial to improve drugs therapeutic effect. Nanotechnology-based delivery systems could be a suitable approach to overcome these limitations. Some of the most important colloidal systems are highlighted in this review, such as the use of mucoadhesive polymers, prodrugs, nanogels, liposomes, microemulsions, lipid and polymeric nanoparticles, cyclodextrins, dendrimers and nanocrystals, along with their clinical and therapeutic relevance for the administration of drugs for ocular delivery.

Introduction: The University Hospitals Paris Centre Pharmacy compounds three concentrations of cyclosporine eye drops: 20mg/mL (=2%); 5mg/mL (=0.5%) and 0.5mg/mL (=0.05%). Cyclosporine A 2% drops were developed in 1995 to prevent the rejection of high-risk cornea transplants after failure of topical steroids. The other concentrations of eye drops were developed for the treatment of various immune or inflammatory diseases of the cornea, conjunctiva and uvea. These eye drops are dispensed with a physician's prescription to hospitalized or ambulatory patients. A retrospective study over 4 years (2009-2013) was conducted to analyze the details of prescription and possible adverse events., Materials and Methods: Dispensations made from January 1st, 2009 through December 31st, 2013 were studied, including patient age, dose of cyclosporine and practice location of prescribing physician. We also recorded the indications for cyclosporine eye drops in a sample of ambulatory patients. The analysis of local tolerability and the effect on visual comfort was based on questionnaires sent to the patients on cyclosporine 2% over a period of 2 months., Results: Cyclosporine eye drops prescription grew continuously from 2009 through 2013 for all concentrations. In 2013, 5,859 patients were treated, among which 3,616 patients with topical cyclosporine 2%, 1,681 patients with 0.5%, and 562 patients with 0.05%. In total, this represents 62,621 eye drops. Treated patients ranged from 1 week to 100 years old. Topical 2% cyclosporine is indicated in 61% of cases to prevent high-risk corneal graft rejection. Other indications are corneal ulcer (6%), atopic keratoconjunctivitis (5%), vernal keratoconjunctivitis (5%) and herpetic keratitis (4%). Topical 0.5% cyclosporine is prescribed primarily for dry eye syndrome (20%) and to prevent rejection of high-risk corneal transplantation (11%), to treat ocular rosacea (10%), vernal keratoconjunctivitis (10%), atopic keratoconjunctivitis (8%) and Sjögren's syndrome (7%). Topical 0.05% cyclosporine is prescribed primarily for dry eye syndrome resistant to conventional treatment (47%) and Sjögren's syndrome (21%). Local tolerability of topical cyclosporine was evaluated in 388 patients. The majority of patients (63%) did not experience any adverse effects. The main side effects are redness, burning sensation and itching., Conclusion: Prescription of various formulations of topical cyclosporine is current practice for surgical indications: rejection of high-risk corneal transplantation; or medical indications: vernal or atopic keratoconjunctivitis and dry eye syndrome. Further prospective randomized studies would be necessary to validate formulations, doses and indications of cyclosporine eye drops., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

This study aimed to develop a cationic nanosuspension of chitosan (CS) and methoxy poly(ethylene glycol)-poly(ε-caprolactone) (MPEG-PCL) for ocular delivery of diclofenac (DIC). MPEG-PCL-CS block polymer was synthesized by covalent coupling of MPEG-PCL with CS. The critical micelle concentration of the MPEG-PCL-CS block polymer was 0.000692 g/L. DIC/MPEG-PCL-CS nanosuspension (mean particle size = 105 nm, zeta potential = 8 mV) was prepared and characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry. The nanosuspension was very stable without apparent physical property changes after storage at 4 °C or 25 °C for 20 days, but it was unstable in the aqueous humor solution after 24 h incubation. Sustained release of the encapsulated DIC from the nanosuspension occurred over 8 h. Neither a blank MPEG-PCL-CS nanosuspension nor a 0.1% (mass fraction) DIC/MPEG-PCL-CS nanosuspension caused ocular irritation after 24 h of instillation. Enhanced penetration and retention in corneal tissue was achieved with a Nile red/MPEG-PCL-CS nanosuspension compared with a Nile red aqueous solution. In vivo pharmacokinetics studies showed enhanced pre-corneal retention and penetration of the DIC/MPEG-PCL-CS nanosuspension, which resulted in a higher concentration of DIC (Cmax) in the aqueous humor and better bioavailability compared with commercial DIC eye drops (P < 0.01).

The bioavailability of drugs used on mucosal surfaces can be increased by the use of mucoadhesive polymers. A new type of mucoadhesive polymers is the group of thiolated polymers with thiol group containing side chains. These polymers are able to form covalent bonds (disulphide linkages) with the mucin glycoproteins. For the formulation of an ocular drug delivery system (DDS) thiolated poly(aspartic acid) polymer (ThioPASP) was used. Our aim was to determine their biocompatibility, mucoadhesion and drug release property. According to the results it can be established that the thiolated poly(aspartic acid) polymers can be a potential vehicle of an ocular drug delivery system due to their biocompatibility, good mucoadhesive property and drug release profile. Thanks to their properties controlled drug delivery can be achieved and bioavailability of the ophthalmic formulation can be increased, while the usage frequency can be decreased.

Various strategies for ocular drug delivery are considered; from basic formulation techniques for improving availability of drugs; viscosity enhancers and mucoadhesives aid drug retention and penetration enhancers promote drug transport into the eye. The use of drug-loaded contact lenses and ocular inserts allows drugs to be better placed where they are needed for more direct delivery. Developments in ocular implants gives a means to overcome the physical barriers that traditionally prevented effective treatment. Implant technologies are under development allowing long-term drug delivery from a single procedure, these devices allow posterior chamber diseases to be effectively treated. Future developments could bring artificial corneas to eliminate the need for donor tissue and one-off implantable drug depots lasting the patient's lifetime.

The present investigation was undertaken to evaluate the possible ocular phototoxicity of drugs used in ophthalmic formulations. Sulphacetamide, ketoconazole, voriconazole, diclofenac, and ketorolac were assessed in the concentrations available in the market for their ocular use. The suitable models viz Hen's Egg Test Chorioallantoic Membrane (HET-CAM) test, Isolated Chicken Eye (ICE) test, and Red Blood Cell (RBC) haemolysis test as recommended by ECVAM, ICCVAM, and OECD guidelines were performed. Results of HET-CAM and ICE tests suggest that sulphacetamide is moderately toxic in the presence of light/UV-A and very slightly irritant without irradiation. Ketoconazole and voriconazole were found slightly irritant in presence of light/UV-A and non-irritant in dark. Diclofenac and ketorolac demonstrated slight irritancy in the light and were found to be non-irritant in dark. The results suggest that some of the drugs have potential toxic effect in the presence of light. The extent of phototoxicity might get extended when used for longer time. The recommendation is that these drugs should be stored and used in the dark for a specified time and be labelled with specific instructions for patients, especially for those working longer in the sunlight.

Background and Objectives: Nerve growth factor (NGF) is a neurotrophin with therapeutic possibilities that extend from the nervous system to the eye. We tested the safety, maximal tolerated dose, pharmacokinetics, and antigenicity of a novel human recombinant NGF (rhNGF) eye-drop formulation in a phase I study., Methods: This prospective, randomized, double-masked, vehicle-controlled trial, sponsored by Dompé SpA (registered as NCT01744704 at ClinicalTrials.gov), enrolled 74 healthy volunteers (24 females, 50 males, age 40.2 ± 11.8 years). Subjects were randomized in three cohorts to receive (1) a single eye-drop containing 0.0175, 0.175, or 0.7 μg rhNGF; (2) a single ascending dose of rhNGF eye drops three times a day for 1 day (total daily dose 2.1, 6.3, or 18.9 μg), or vehicle; or (3) a multiple ascending dose of rhNGF eye drops three times a day for 5 days (total dose 10.5, 31.5, or 94.5 μg), or vehicle. Outcome measures included blood chemistry, urinalyses, vital signs, electrocardiograms (ECGs), serum NGF antibodies, ocular and systemic adverse events (AEs), visual acuity, tear function, intraocular pressure, fundus oculi, and ocular symptoms., Results: Administration of rhNGF eye drops did not result in a significant increase of circulating NGF levels and no antidrug antibodies were detected in serum. No serious AEs were recorded, and a few mild, transient ocular AEs related to rhNGF administration were reported only at the highest concentration., Conclusions: rhNGF eye drops were well tolerated, with no detectable clinical evidence of systemic AEs. These results pave the way for the development of clinical trials on rhNGF in ophthalmology.

This paper describes hitherto developed drug forms for topical ocular administration, that is, eye drops, ointments, in situ gels, inserts, multicompartment drug delivery systems, and ophthalmic drug forms with bioadhesive properties. Heretofore, many studies have demonstrated that new and more complex ophthalmic drug forms exhibit advantage over traditional ones and are able to increase the bioavailability of the active substance by, among others, reducing the susceptibility of drug forms to defense mechanisms of the human eye, extending contact time of drug with the cornea, increasing the penetration through the complex anatomical structure of the eye, and providing controlled release of drugs into the eye tissues, which allows reducing the drug application frequency. The rest of the paper describes recommended in vitro and in vivo studies to be performed for various ophthalmic drugs forms in order to assess whether the form is acceptable from the perspective of desired properties and patient's compliance.