The Experts below are selected from a list of 12417 Experts worldwide ranked by ideXlab platform
Ashim K Mitra - One of the best experts on this subject based on the ideXlab platform.
-
Role of membrane transporters and metabolizing enzymes in Ocular Drug delivery.
Current drug metabolism, 2015Co-Authors: Ramya Krishna Vadlapatla, Aswani Dutt Vadlapudi, Dhananjay Pal, Ashim K MitraAbstract:Ocular disorders can significantly lower a patient's quality of life. Centers for Disease Control and Prevention's Vision Health Initiative have estimated that the number of people affected by age-related Ocular diseases may be doubled in the United States by 2030. Although availability of newer therapeutics has improved the prognosis of Ocular diseases, poor Ocular bioavailability still remains a major concern. Combinations of pharmacodynamic and pharmacokinetic barriers have been known to determine the amount of Drug delivered to the target tissue. However, presence of membrane transporters and metabolizing enzymes pose a significant challenge to Ocular Drug disposition. Scientific literature confirms the expression of efflux/ATP-binding cassette transporters, influx/solute carrier transporters and several metabolic enzymes including oxidoreductases, hydrolases and transferases in different Ocular tissues. Therefore, this review article describes the anatomical features of the eye and various barriers regulating Ocular Drug disposition. Differential expression of membrane transporters and metabolizing enzymes in normal and diseased states are briefly discussed. Further, the significance of transporter- metabolism interplay in ophthalmic Drug design and various Ocular Drug delivery strategies are also outlined.
-
Ocular Drug delivery systems: An overview.
World journal of pharmacology, 2015Co-Authors: Ashaben Patel, Kishore Cholkar, Vibhuti Agrahari, Ashim K MitraAbstract:The major challenge faced by today's pharmacologist and formulation scientist is Ocular Drug delivery. Topical eye drop is the most convenient and patient compliant route of Drug administration, especially for the treatment of anterior segment diseases. Delivery of Drugs to the targeted Ocular tissues is restricted by various precorneal, dynamic and static Ocular barriers. Also, therapeutic Drug levels are not maintained for longer duration in target tissues. In the past two decades, Ocular Drug delivery research acceleratedly advanced towards developing a novel, safe and patient compliant formulation and Drug delivery devices/techniques, which may surpass these barriers and maintain Drug levels in tissues. Anterior segment Drug delivery advances are witnessed by modulation of conventional topical solutions with permeation and viscosity enhancers. Also, it includes development of conventional topical formulations such as suspensions, emulsions and ointments. Various nanoformulations have also been introduced for anterior segment Ocular Drug delivery. On the other hand, for posterior Ocular delivery, research has been immensely focused towards development of Drug releasing devices and nanoformulations for treating chronic vitreoretinal diseases. These novel devices and/or formulations may help to surpass Ocular barriers and associated side effects with conventional topical drops. Also, these novel devices and/or formulations are easy to formulate, no/negligibly irritating, possess high precorneal residence time, sustain the Drug release, and enhance Ocular bioavailability of therapeutics. An update of current research advancement in Ocular Drug delivery necessitates and helps Drug delivery scientists to modulate their think process and develop novel and safe Drug delivery strategies. Current review intends to summarize the existing conventional formulations for Ocular delivery and their advancements followed by current nanotechnology based formulation developments. Also, recent developments with other Ocular Drug delivery strategies employing in situ gels, implants, contact lens and microneedles have been discussed.
-
Episcleral, intrascleral, and suprachoroidal routes of Ocular Drug delivery - recent research advances and patents.
Recent patents on drug delivery & formulation, 2014Co-Authors: Brian C. Gilger, Abhirup Mandal, Sujay Shah, Ashim K MitraAbstract:Subconjunctival/episcleral, intrascleral, and suprachoroidal routes of Drug delivery for treatment of posterior segment eye diseases have become more feasible and popular in the past few years. These routes have the advantage of bypassing the main barriers to topical Drug penetration, the Ocular surface epithelium, the conjunctivallymphatics, and in the case of deep intrascleral and suprachoroidial delivery, the sclera barrier. Many Ocular Drug delivery application devices, Drug delivery methods, and therapeutics that have been developed for intravitreal use can also be used subconjunctivally, intrasclerally, and in the suprachoroidal space. Alternatively, site-specific devices, such microneedles, and therapeutics, such as hydrogel matrices, have been developed to enhance Ocular Drug delivery. This manuscript will review the recent research advances and patents on episcleral, intrascleral, and suprachoroidal routes of Ocular Drug delivery.
-
Controlled Ocular Drug delivery with nanomicelles
Wiley interdisciplinary reviews. Nanomedicine and nanobiotechnology, 2014Co-Authors: Ravi Vaishya, Varun Khurana, Sulabh P. Patel, Ashim K MitraAbstract:Many vision threatening Ocular diseases such as age-related macular degeneration (AMD), diabetic retinopathy, glaucoma, and proliferative vitreoretinopathy may result in blindness. Ocular Drug delivery specifically to the intraOcular tissues remains a challenging task due to the presence of various physiological barriers. Nonetheless, recent advancements in the field of nanomicelle-based novel Drug delivery system could fulfil these unmet needs. Nanomicelles consists of amphiphilic molecules that self-assemble in aqueous media to form organized supramolecular structures. Micelles can be prepared in various sizes (10–1000 nm) and shapes depending on the molecular weights of the core and corona forming blocks. Nanomicelles have been an attractive carrier for their potential to solubilize hydrophobic molecules in aqueous solution. In addition, small size in nanometer range and highly modifiable surface properties have been reported to be advantageous in Ocular Drug delivery. In this review, various factors influencing rationale design of nanomicelles formulation and disposition are discussed along with case studies. Despite the progress in the field, influence of various properties of nanomicelles such as size, shape, surface charge, rigidity of structure on Ocular disposition need to be studied in further details to develop an efficient nanocarrier system. ©
-
Microdialysis in Ocular Drug Development
Microdialysis in Drug Development, 2012Co-Authors: Mitesh Patel, Nanda K. Mandava, Ashim K MitraAbstract:Development of novel treatments for Ocular diseases demands a complete understanding of Ocular Drug pharmacokinetics. Microdialysis is a continuous sampling technique that has been frequently applied for assessing Ocular pharmacokinetic parameters. This sampling technique has gained considerable attention in Ocular pharmacokinetics since it considerably reduces the requirement of large number of animals needed to obtain a complete pharmacokinetic profile. Remarkable progress has been made in Ocular anterior and posterior segment microdialysis in recent years. These developments have simplified sampling of Ocular fluids such as vitreous and aqueous humor. In this book chapter, the principle and application of microdialysis in measuring Drug disposition in various segments of the eye will be discussed. This chapter will also highlight on recent progress on the development of various animal models and probe designs in Ocular microdialysis.
Surajit Dey - One of the best experts on this subject based on the ideXlab platform.
-
Transporters and receptors in Ocular Drug delivery: opportunities and challenges.
Expert opinion on drug delivery, 2005Co-Authors: Surajit Dey, Ashim K MitraAbstract:In this editorial, the opportunities and challenges of transporter/receptor mediated Ocular Drug delivery are discussed.
-
Transporters/receptors in the anterior chamber: pathways to explore Ocular Drug delivery strategies.
Expert opinion on biological therapy, 2003Co-Authors: Surajit Dey, Banmeet S. Anand, Jignesh Patel, Ashim K MitraAbstract:Membrane transporters/receptors are involved in Drug transport processes and play a key role in intestinal absorption, tissue distribution and elimination. Drug targeting to specific transporters and receptors using carrier-mediated absorption has immense clinical significance. Ocular Drug delivery is a challenging task since it involves Drug transport across various barriers in the eye. Specialised transport processes exist at these barriers, which control the entry of Drugs and xenobiotics. Ocular Drug therapy involving topical or systemic administration of Drugs has various limitations. Transport processes in the eye have been targeted in an effort to increase Ocular bioavailability of Drugs following topical instillation. This review discusses various transport processes in the eye and Drug delivery strategies utilising these transporters/receptors.
Allan E. David - One of the best experts on this subject based on the ideXlab platform.
-
Evaluation of commercial soft contact lenses for Ocular Drug delivery: A review.
Acta biomaterialia, 2020Co-Authors: Xin Fan, Cesar Torres-luna, Marjan Azadi, Roman Domszy, Arthur Yang, Allan E. DavidAbstract:Abstract Soft contact lenses have generated growing interest in Ocular Drug delivery due to their potential to enhance Drug bioavailability in Ocular tissues. Commercially available soft contact lenses offer several advantages for Ocular Drug delivery as they are manufactured on a large scale, which guarantees the availability of a consistent and reproducible product, and their favorable safety profile is well-established through broad clinical use. Here we review the rationale for using commercially available soft contact lenses for Ocular Drug delivery; summarize the evolution of the materials used in contact lens fabrication; and explore various methods used to improve the Drug release characteristics and its tissue penetration. While significant progress has been made, several issues still require further attention for the commercial launch of a viable Drug-eluting contact lens product, including control of initial burst release, shelf-life stability, and Drug loss during processing or storage.
Arto Urtti - One of the best experts on this subject based on the ideXlab platform.
-
Polysaccharides in Ocular Drug Delivery
Pharmaceutics, 2019Co-Authors: Natallia V. Dubashynskaya, Arto Urtti, Daria N. Poshina, Sergei V. Raik, Yury A. SkorikAbstract:Polysaccharides, such as cellulose, hyaluronic acid, alginic acid, and chitosan, as well as polysaccharide derivatives, have been successfully used to augment Drug delivery in the treatment of Ocular pathologies. The properties of polysaccharides can be extensively modified to optimize Ocular Drug formulations and to obtain biocompatible and biodegradable Drugs with improved bioavailability and tailored pharmacological effects. This review discusses the available polysaccharide choices for overcoming the difficulties associated with Ocular Drug delivery, and it explores the reasons for the dependence between the physicochemical properties of polysaccharide-based Drug carriers and their efficiency in different formulations and applications. Polysaccharides will continue to be of great interest to researchers endeavoring to develop ophthalmic Drugs with improved effectiveness and safety.
-
ISOPT Clinical Hot Topic Panel Discussion on Ocular Drug Delivery
Journal of ocular pharmacology and therapeutics : the official journal of the Association for Ocular Pharmacology and Therapeutics, 2019Co-Authors: Uday B. Kompella, Arto Urtti, Abraham J. Domb, Ashwath Jayagopal, Clive G. Wilson, Diane D.-s. Tang-liuAbstract:Ocular Drug delivery offers unique challenges and opportunities in the era of novel therapeutic agents ranging from small molecules to gene therapies. Noninvasive delivery of Drugs into the back of the eye or any part of the eye is extremely limited by short precorneal residence time and formidable biological barriers. The eye is a sensitive, sensory organ that requires a high level of material and procedural safety, while achieving therapeutic efficacy. Some recent advances and unmet needs for Ocular Drug delivery and disposition are discussed in this article. Specifically, nanomedicines, physical and chemical means to enhance delivery, stimuli-responsive delivery systems, the role of vitreal binding on Ocular pharmacokinetics, and the influence of aging eye on Drug delivery, and the associated unmet needs are highlighted. Additionally, the unmet needs in the medication management for the elderly patients with eye diseases are discussed.
-
Implications of melanin binding in Ocular Drug delivery.
Advanced drug delivery reviews, 2017Co-Authors: Anna-kaisa Rimpelä, Arto Urtti, Heidi Kidron, Mika Reinisalo, Laura Hellinen, Evgeni Grazhdankin, Eva M. Del AmoAbstract:Pigmented Ocular tissues contain melanin within the intracellular melanosomes. Drugs bind to melanin at varying extent that ranges from no binding to extensive binding. Binding may lead to Drug accumulation to the pigmented tissues and prolonged Drug retention in the melanin containing cells. Therefore, melanin binding is an important feature that affects Ocular Drug delivery and biodistribution, but this topic has not been reviewed since 1998. In this review, we present current knowledge on Ocular melanin, melanosomes and binding of Drugs to pigmented cells and tissues. In vitro, in vivo and in silico methods in the field were critically evaluated, because the literature in this field can be confusing if the reader does not properly understand the methodological aspects. Literature analysis includes a comprehensive table of literature data on melanin binding of Drugs. Furthermore, we aimed to give some insights beyond the current literature by making a chemical structure based classification model for melanin binding of Drugs and kinetic simulations that revealed significant interplay between melanin binding and Drug permeability across the melanosomal and plasma membranes. Overall, more mechanistic and systematic research is needed before the impact of melanin binding on Ocular Drug delivery can be properly understood and predicted.
-
General Pharmacokinetic Model for Topically Administered Ocular Drug Dosage Forms
Pharmaceutical research, 2016Co-Authors: Feng Deng, Veli-pekka Ranta, Heidi Kidron, Arto UrttiAbstract:Purpose In Ocular Drug development, an early estimate of Drug behavior before any in vivo experiments is important. The pharmacokinetics (PK) and bioavailability depend not only on active compound and excipients but also on physicochemical properties of the Ocular Drug formulation. We propose to utilize PK modelling to predict how Drug and formulational properties affect Drug bioavailability and pharmacokinetics.
-
Undefined role of mucus as a barrier in Ocular Drug delivery
European Journal of Pharmaceutics and Biopharmaceutics, 2015Co-Authors: Marika Ruponen, Arto UrttiAbstract:Mucus layer covers the Ocular surface, and soluble mucins are also present in the tear fluid. After topical Ocular Drug administration, the Drugs and formulations may interact with mucus layer that may act as a barrier in Ocular Drug delivery. In this mini-review, we illustrate the mucin composition of the Ocular surface and discuss the influence of mucus layer on Ocular Drug absorption. Based on the current knowledge the role of mucus barrier in Drug delivery is still undefined. Furthermore, interactions with mucus may prolong the retention of Drug formulations on the Ocular surface. Mucus may decrease or increase Ocular bioavailability depending on the magnitude of its role as barrier or retention site, respectively. Mechanistic studies are needed to clarify the role of mucin in Ocular Drug delivery.
Ji-yan Liu - One of the best experts on this subject based on the ideXlab platform.
-
iRGD decorated liposomes: A novel actively penetrating topical Ocular Drug delivery strategy
Nano Research, 2020Co-Authors: Hai Huang, Xiaorong Yang, James Trevor Oswald, Yongmei Liu, Jun Zeng, Chaohui Jin, Xingchen Peng, Ji-yan LiuAbstract:Ocular Drug delivery remains a significant challenge that is limited by poor corneal retention and permeation, resulting in low Ocular bioavailability (< 5%). Worse still, the most convenient and safe route of Ocular Drug administration, topical administration results in a Drug bioavailability of less than 1%. iRGD modified Drug delivery strategies have been developed for cancer therapy, however active targeting iRGD platforms for Ocular Drug delivery have yet to be explored. Herein, an iRGD modified liposomes was developed for Ocular Drug delivery via topical administration. The results indicated that iRGD modified liposomes could prolong the corneal retention time and enhance corneal permeability in an iRGD receptor mediated manner. These findings provided a novel strategy for topical Ocular Drug delivery for the treatment of posterior Ocular diseases.
