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Ingabire D, Qin C, Meng T, Raynold AAM, Sudarjat H, Townsend EA, Pangeni R, Poudel S, Arriaga M, Zhao L, Chow WN, Banks M, Xu Q. Nor-LAAM loaded PLGA microparticles for treating opioid use disorder. J Control Release 2024; 373:93-104. [PMID: 38968971 DOI: 10.1016/j.jconrel.2024.06.071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 06/08/2024] [Accepted: 06/30/2024] [Indexed: 07/07/2024]
Abstract
The treatment landscape for opioid use disorder (OUD) faces challenges stemming from the limited efficacy of existing medications, poor adherence to prescribed regimens, and a heightened risk of fatal overdose post-treatment cessation. Therefore, there is a pressing need for innovative therapeutic strategies that enhance the effectiveness of interventions and the overall well-being of individuals with OUD. This study explored the therapeutic potential of nor-Levo-α-acetylmethadol (nor-LAAM) to treat OUD. We developed sustained release nor-LAAM-loaded poly (lactic-co-glycolic acid) (PLGA) microparticles (MP) using a hydrophobic ion pairing (HIP) approach. The nor-LAAM-MP prepared using HIP with pamoic acid had high drug loading and exhibited minimal initial burst release and sustained release. The nor-LAAM-MP was further optimized for desirable particle size, drug loading, and release kinetics. The lead nor-LAAM-MP (F4) had a relatively high drug loading (11 wt%) and an average diameter (19 μm) and maintained a sustained drug release for 4 weeks. A single subcutaneous injection of nor-LAAM-MP (F4) provided detectable nor-LAAM levels in rabbit plasma for at least 15 days. We further evaluated the therapeutic efficacy of nor-LAAM-MP (F4) in a well-established fentanyl-addiction rat model, and revealed a marked reduction in fentanyl choice and withdrawal symptoms in fentanyl-dependent rats. These findings provide insights into further developing long-acting nor-LAAM-MP for treating OUD. It has the potential to offer a new effective medication to the existing sparse armamentarium of products available to treat OUD.
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Affiliation(s)
- Diane Ingabire
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA; Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Chaolong Qin
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Tuo Meng
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
| | | | - Hadi Sudarjat
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - E Andrew Townsend
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Rudra Pangeni
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Sagun Poudel
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Michelle Arriaga
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Long Zhao
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Woon N Chow
- Department of Ophthalmology, Virginia Commonwealth University, Richmond, VA 23298, USA; Department of Pathology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Matthew Banks
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA.
| | - Qingguo Xu
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA; Department of Ophthalmology, Virginia Commonwealth University, Richmond, VA 23298, USA; Center for Pharmaceutical Engineering, and Institute for Structural Biology, Drug Discovery & Development (ISB3D), Massey Cancer Center, Virginia Commonwealth University, Richmond, VA 23298, USA.
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2
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Ingabire D, Qin C, Meng T, Raynold AAM, Sudarjat H, Townsend EA, Pangeni R, Poudel S, Arriaga M, Zhao L, Chow WN, Banks M, Xu Q. Nor-LAAM loaded PLGA Microparticles for Treating Opioid Use Disorder. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.08.588574. [PMID: 38645066 PMCID: PMC11030377 DOI: 10.1101/2024.04.08.588574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
The treatment landscape for opioid use disorder (OUD) faces challenges stemming from the limited efficacy of existing medications, poor adherence to prescribed regimens, and a heightened risk of fatal overdose post-treatment cessation. Therefore, there is a pressing need for innovative therapeutic strategies that enhance the effectiveness of interventions and the overall well-being of individuals with OUD. This study explored the therapeutic potential of nor-Levo-α-acetylmethadol (nor-LAAM) to treat OUD. We developed sustained release nor-LAAM-loaded poly (lactic-co-glycolic acid) (PLGA) microparticles (MP) using a hydrophobic ion pairing (HIP) approach. The nor-LAAM-MP prepared using HIP with pamoic acid had high drug loading and exhibited minimal initial burst release and sustained release. The nor-LAAM-MP was further optimized for desirable particle size, drug loading, and release kinetics. The lead nor-LAAM-MP (F4) had a relatively high drug loading (11 wt.%) and an average diameter (19 µm) and maintained a sustained drug release for 4 weeks. A single subcutaneous injection of nor-LAAM-MP (F4) provided detectable nor-LAAM levels in rabbit plasma for at least 15 days. We further evaluated the therapeutic efficacy of nor-LAAM-MP (F4) in a well-established fentanyl-addiction rat model, and revealed a marked reduction in fentanyl choice and withdrawal symptoms in fentanyl-dependent rats. These findings provide insights into further developing long-acting nor-LAAM-MP for treating OUD. It has the potential to offer a new effective medication to the existing sparse armamentarium of products available to treat OUD.
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Mostafa M, Al Fatease A, Alany RG, Abdelkader H. Recent Advances of Ocular Drug Delivery Systems: Prominence of Ocular Implants for Chronic Eye Diseases. Pharmaceutics 2023; 15:1746. [PMID: 37376194 DOI: 10.3390/pharmaceutics15061746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/02/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
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.
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Affiliation(s)
- Mahmoud Mostafa
- Department of Pharmaceutics, Faculty of Pharmacy, Minia University, Minya 61519, Egypt
| | - Adel Al Fatease
- Department of Pharmaceutics, College of Pharmacy, King Khalid University, Abha 62223, Saudi Arabia
| | - Raid G Alany
- School of Pharmacy, Kingston University London, Kingston Upon Tames KT1 2EE, UK
- School of Pharmacy, The University of Auckland, Auckland 1010, New Zealand
| | - Hamdy Abdelkader
- Department of Pharmaceutics, College of Pharmacy, King Khalid University, Abha 62223, Saudi Arabia
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4
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Wu KY, Joly-Chevrier M, Akbar D, Tran SD. Overcoming Treatment Challenges in Posterior Segment Diseases with Biodegradable Nano-Based Drug Delivery Systems. Pharmaceutics 2023; 15:pharmaceutics15041094. [PMID: 37111579 PMCID: PMC10142934 DOI: 10.3390/pharmaceutics15041094] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/20/2023] [Accepted: 03/21/2023] [Indexed: 04/29/2023] Open
Abstract
Posterior segment eye diseases present a challenge in treatment due to the complex structures in the eye that serve as robust static and dynamic barriers, limiting the penetration, residence time, and bioavailability of topical and intraocular medications. This hinders effective treatment and requires frequent dosing, such as the regular use of eye drops or visits to the ophthalmologist for intravitreal injections, to manage the disease. Moreover, the drugs must be biodegradable to minimize toxicity and adverse reactions, as well as small enough to not affect the visual axis. The development of biodegradable nano-based drug delivery systems (DDSs) can be the solution to these challenges. First, they can stay in ocular tissues for longer periods of time, reducing the frequency of drug administration. Second, they can pass through ocular barriers, offering higher bioavailability to targeted tissues that are otherwise inaccessible. Third, they can be made up of polymers that are biodegradable and nanosized. Hence, therapeutic innovations in biodegradable nanosized DDS have been widely explored for ophthalmic drug delivery applications. In this review, we will present a concise overview of DDSs utilized in the treatment of ocular diseases. We will then examine the current therapeutic challenges faced in the management of posterior segment diseases and explore how various types of biodegradable nanocarriers can enhance our therapeutic arsenal. A literature review of the pre-clinical and clinical studies published between 2017 and 2023 was conducted. Through the advances in biodegradable materials, combined with a better understanding of ocular pharmacology, the nano-based DDSs have rapidly evolved, showing great promise to overcome challenges currently encountered by clinicians.
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Affiliation(s)
- Kevin Y Wu
- Department of Surgery, Division of Ophthalmology, University of Sherbrooke, Sherbrooke, QC J1G 2E8, Canada
| | | | - Dania Akbar
- Department of Human Biology, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Simon D Tran
- Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC H3A 1G1, Canada
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Meng T, Zheng J, Chen M, Zhao Y, Sudarjat H, M.R. AA, Kulkarni V, Oh Y, Xia S, Ding Z, Han H, Anders N, Rudek MA, Chow W, Stark W, Ensign LM, Hanes J, Xu Q. Six-month effective treatment of corneal graft rejection. SCIENCE ADVANCES 2023; 9:eadf4608. [PMID: 36947612 PMCID: PMC10032610 DOI: 10.1126/sciadv.adf4608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 02/17/2023] [Indexed: 06/18/2023]
Abstract
Topical corticosteroid eye drop is the mainstay for preventing and treating corneal graft rejection. While the frequent topical corticosteroid use is associated with risk of intraocular pressure (IOP) elevation and poor patient compliance that leads to graft failure and the requirement for a repeated, high-risk corneal transplantation. Here, we developed dexamethasone sodium phosphate (DSP)-loaded dicarboxyl-terminated poly(lactic acid) nanoparticle (PLA DSP-NP) formulations with relatively high drug loading (8 to 10 weight %) and 6 months of sustained intraocular DSP delivery in rats with a single dosing. PLA DSP-NP successfully reversed early signs of corneal rejection, leading to rat corneal graft survival for at least 6 months. Efficacious PLA DSP-NP doses did not affect IOP and showed no signs of ocular toxicity in rats for up to 6 months. Subconjunctival injection of DSP-NP is a promising approach for safely preventing and treating corneal graft rejection with the potential for improved patient adherence.
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Affiliation(s)
- Tuo Meng
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Jinhua Zheng
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
- Department of Ophthalmology, Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou 550004, China
| | - Min Chen
- Eye Institute of Shandong First Medical University, Qingdao Eye Hospital of Shandong First Medical University, Qingdao, Shandong 266073, China
- Department of Ophthalmology, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
- Center for Nanomedicine, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
| | - Yang Zhao
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
- Department of Ophthalmology, Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Hadi Sudarjat
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Aji Alex M.R.
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Vineet Kulkarni
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Yumin Oh
- Center for Nanomedicine, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
| | - Shiyu Xia
- Center for Nanomedicine, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
| | - Zheng Ding
- Center for Nanomedicine, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
| | - Hyounkoo Han
- Department of Ophthalmology, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
- Center for Nanomedicine, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
| | - Nicole Anders
- Department of Medicine, The Johns Hopkins University, Baltimore, MD 21231, USA
| | - Michelle A. Rudek
- Department of Medicine, The Johns Hopkins University, Baltimore, MD 21231, USA
| | - Woon Chow
- Department of Ophthalmology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Walter Stark
- Department of Ophthalmology, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
- Center for Nanomedicine, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
| | - Laura M. Ensign
- Department of Ophthalmology, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
- Center for Nanomedicine, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
| | - Justin Hanes
- Department of Ophthalmology, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
- Center for Nanomedicine, The Johns Hopkins University School of Medicine, 400 North Broadway, Baltimore, MD 21231, USA
| | - Qingguo Xu
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA 23298, USA
- Department of Ophthalmology, Virginia Commonwealth University, Richmond, VA 23298, USA
- Center for Pharmaceutical Engineering and Institute for Structural Biology, Drug Discovery and Development (ISB3D), Massey Cancer Center, Virginia Commonwealth University, Richmond, VA 23298, USA
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Ahmed S, Amin MM, Sayed S. Ocular Drug Delivery: a Comprehensive Review. AAPS PharmSciTech 2023; 24:66. [PMID: 36788150 DOI: 10.1208/s12249-023-02516-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 01/14/2023] [Indexed: 02/16/2023] Open
Abstract
The human eye is a sophisticated organ with distinctive anatomy and physiology that hinders the passage of drugs into targeted ophthalmic sites. Effective topical administration is an interest of scientists for many decades. Their difficult mission is to prolong drug residence time and guarantee an appropriate ocular permeation. Several ocular obstacles oppose effective drug delivery such as precorneal, corneal, and blood-corneal barriers. Routes for ocular delivery include topical, intravitreal, intraocular, juxtascleral, subconjunctival, intracameral, and retrobulbar. More than 95% of marketed products exists in liquid state. However, other products could be in semi-solid (ointments and gels), solid state (powder, insert and lens), or mixed (in situ gel). Nowadays, attractiveness to nanotechnology-based carries is resulted from their capabilities to entrap both hydrophilic and lipophilic drugs, enhance ocular permeability, sustain residence time, improve drug stability, and augment bioavailability. Different in vitro, ex vivo, and in vivo characterization approaches help to predict the outcomes of the constructed nanocarriers. This review aims to clarify anatomy of the eye, various ocular diseases, and obstacles to ocular delivery. Moreover, it studies the advantages and drawbacks of different ocular routes of administration and dosage forms. This review also discusses different nanostructured platforms and their characterization approaches. Strategies to enhance ocular bioavailability are also explained. Finally, recent advances in ocular delivery are described.
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Affiliation(s)
- Sadek Ahmed
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Kasr El-Aini, Cairo, 11562, Egypt.
| | - Maha M Amin
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Kasr El-Aini, Cairo, 11562, Egypt
| | - Sinar Sayed
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Kasr El-Aini, Cairo, 11562, Egypt
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Cvenkel B, Kolko M. Devices and Treatments to Address Low Adherence in Glaucoma Patients: A Narrative Review. J Clin Med 2022; 12:jcm12010151. [PMID: 36614952 PMCID: PMC9821329 DOI: 10.3390/jcm12010151] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/05/2022] [Accepted: 12/21/2022] [Indexed: 12/28/2022] Open
Abstract
Poor adherence to topical glaucoma medications has been linked to worse visual field outcomes in glaucoma patients. Therefore, identifying and overcoming the adherence barriers are expected to slow down the progression of disease. The most common barriers to adherence, in addition to the lack of knowledge, include forgetfulness, side effects of medications, difficulties with drop instillation and low self-efficacy. Symptoms and signs of ocular surface disease, which importantly reduce patients' quality of life, are decreased by using preservative-free topical medications. Sustained drug delivery systems using different vehicles seem promising for relieving the burden of drop administration. Currently, only the bimatoprost sustained-release intracameral implant is available for clinical use and single administration. In the era of digitalization, smart drug delivery-connected devices may aid adherence and, by sharing data with care providers, improve monitoring and adjusting treatment. Selective laser trabeculoplasty as first-line treatment delays the need for drops, whereas minimally invasive glaucoma procedures with and without devices combined with cataract surgery increase the likelihood of patients with early-to-moderate glaucoma to remain drop free or reduce the number of drops needed to control intraocular pressure. The aim of this narrative review is to present and discuss devices and treatments that may improve adherence by reducing the need for drops and side effects of medications and aiding in glaucoma monitoring. For the future, there is a need for studies focusing on clinically important outcomes, quality of life and the cost of intervention with longer post-interventional follow up.
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Affiliation(s)
- Barbara Cvenkel
- Department of Ophthalmology, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia
- Medical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
- Correspondence:
| | - Miriam Kolko
- Department of Drug Design and Pharmacology, University of Copenhagen, 2100 Copenhagen, Denmark
- Department of Ophthalmology, Copenhagen University Hospital, Rigshospitalet, 2600 Glostrup, Denmark
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Cai M, Xu Z, Zhou X, Li L, Hua X, Guo S, Yuan X. Long-acting acid-sensitive ketal-linked dexamethasone microcrystals for treating experimental autoimmune uveitis. APL Bioeng 2022; 6:046101. [PMID: 36313265 PMCID: PMC9612960 DOI: 10.1063/5.0118311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 09/26/2022] [Indexed: 11/06/2022] Open
Abstract
Corticosteroids have for some time been used as first-line drugs for the topical treatment of noninfectious uveitis, but poor ocular bioavailability and the rapid clearance of eye drops necessitate frequent dosing, reducing patient compliance. In this study, we used an acid-sensitive stearoxyl-ketal-dexamethasone pro-drug microcrystals (SKD MCs), which is consistently safe and effective in the control of uveitis inflammation in rats. We used a rat model of experimental autoimmune uveitis (EAU) to evaluate the effects of SKD MCs in terms of clinical manifestations, molecular biology, pathological histology, and visual electrophysiology compared to dexamethasone sodium phosphate injection or phosphate-buffered saline. SKD MCs significantly reduced inflammation in EAU, improved the ability to suppress inflammatory cytokines and to protect retinal function, and significantly reduced retinal microglia activation, with no increase in intraocular pressure throughout the treatment. Our results indicate that the SKD MCs formulation holds promise as a new strategy for the treatment of noninfectious uveitis and potentially other ocular inflammatory diseases.
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Affiliation(s)
- Maoyu Cai
- Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China,Tianjin Key Laboratory of Ophthalmology and Visual Science, Tianjin Eye Institute, Tianjin Eye Hospital, Tianjin 300020, China
| | - Zunkai Xu
- Key Laboratory of Functional Polymer Materials of Ministry of Education, State Key Laboratory of Medicinal Chemical Biology and Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xueyan Zhou
- School of Medicine, Nankai University, Tianjin 300071, China
| | - Liangpin Li
- Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China,Tianjin Key Laboratory of Ophthalmology and Visual Science, Tianjin Eye Institute, Tianjin Eye Hospital, Tianjin 300020, China
| | - Xia Hua
- Aier Eye Institute, Changsha 410015, China,Tianjin Aier Eye Hospital, Tianjin 300190, China,Authors to whom correspondence should be addressed:; ; and
| | - Shutao Guo
- Key Laboratory of Functional Polymer Materials of Ministry of Education, State Key Laboratory of Medicinal Chemical Biology and Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China,Authors to whom correspondence should be addressed:; ; and
| | - Xiaoyong Yuan
- Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China,Tianjin Key Laboratory of Ophthalmology and Visual Science, Tianjin Eye Institute, Tianjin Eye Hospital, Tianjin 300020, China,Authors to whom correspondence should be addressed:; ; and
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9
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Spaniol K, Borrelli M, Menzel-Severing J, Geerling G. [Conjunctival reconstruction-State of the art of regenerative treatment forms beyond the limbus]. DIE OPHTHALMOLOGIE 2022; 119:902-909. [PMID: 35925338 DOI: 10.1007/s00347-022-01673-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/25/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND The demands on conjunctival replacement tissues are high: they need to be elastic, clinically compatible, surgically feasible and support goblet cell growth. OBJECTIVE This article provides an overview of currently applied conjunctival replacement tissues and those under investigation. METHOD Current publications on clinically applied conjunctival replacement tissues and substrates which are the subject of scientific research and those already tested in animal models are presented and discussed. RESULTS Replacement tissues in clinical use are autologous and allogenic conjunctiva, nasal and oral mucous membranes, amniotic membrane and decellularized tissues. Autologous conjunctiva shows good results but is not suitable for large defects due to limited availability. In these cases autologous nasal and oral mucous membranes can be used; however, success is limited in cases of autoimmune diseases. Amniotic membranes are frequently applied clinically but goblet cell growth is limited. Different decellularized tissues are used clinically and goblet cell growth was found in vivo. Robust comparative studies are not yet available. Biological matrices such as fibrin, collagen, elastin, gelatin or hyaluronate and synthetic tissues from the group of polyesters are being investigated in the laboratory and in animal models. These studies show good epithelialization and goblet cell growth in vivo. CONCLUSION Transplantation of conjunctiva, nasal and oral mucous membranes and amniotic membranes show satisfactory clinical results but exhibit individual weaknesses. Further studies in animal models and clinical settings are required to further evaluate the benefits of other matrices, such as cell-free tissues or other biological and synthetic matrices.
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Affiliation(s)
- Kristina Spaniol
- Klinik für Augenheilkunde, Universitätsklinikum Düsseldorf, Heinrich-Heine Universität, Moorenstr. 5, 40225, Düsseldorf, Deutschland.
| | - Maria Borrelli
- Klinik für Augenheilkunde, Universitätsklinikum Düsseldorf, Heinrich-Heine Universität, Moorenstr. 5, 40225, Düsseldorf, Deutschland
| | - Johannes Menzel-Severing
- Klinik für Augenheilkunde, Universitätsklinikum Düsseldorf, Heinrich-Heine Universität, Moorenstr. 5, 40225, Düsseldorf, Deutschland
| | - Gerd Geerling
- Klinik für Augenheilkunde, Universitätsklinikum Düsseldorf, Heinrich-Heine Universität, Moorenstr. 5, 40225, Düsseldorf, Deutschland
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10
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Recent advances in ophthalmic preparations: Ocular barriers, dosage forms and routes of administration. Int J Pharm 2021; 608:121105. [PMID: 34537269 DOI: 10.1016/j.ijpharm.2021.121105] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 08/27/2021] [Accepted: 09/13/2021] [Indexed: 12/16/2022]
Abstract
The human eye is a complex organ with unique anatomy and physiology that restricts the delivery of drugs to target ocular tissues/sites. Recent advances in the field of pharmacy, biotechnology and material science have led to development of novel ophthalmic dosage forms which can provide sustained drug delivery, reduce dosing frequency and improve the ocular bioavailability of drugs. This review highlights the different anatomical and physiological factors which affect ocular bioavailability of drugs and explores advancements from 2016 to 2020 in various ophthalmic preparations. Different routes of drug administration such as topical, intravitreal, intraocular, juxtascleral, subconjunctival, intracameral and retrobulbar are discussed with their advances and limitations.
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11
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Ion-Complex Microcrystal Formulation Provides Sustained Delivery of a Multimodal Kinase Inhibitor from the Subconjunctival Space for Protection of Retinal Ganglion Cells. Pharmaceutics 2021; 13:pharmaceutics13050647. [PMID: 34062883 PMCID: PMC8147274 DOI: 10.3390/pharmaceutics13050647] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 04/27/2021] [Accepted: 04/29/2021] [Indexed: 02/07/2023] Open
Abstract
Glaucoma is the leading cause of irreversible blindness worldwide. Elevated intraocular pressure (IOP) is one of the major risk factors for glaucoma onset and progression, and available pharmaceutical interventions are exclusively targeted at IOP lowering. However, degeneration of retinal ganglion cells (RGCs) may continue to progress despite extensive lowering of IOP. A complementary strategy to IOP reduction is the use of neuroprotective agents that interrupt the process of cell death by mechanisms independent of IOP. Here, we describe an ion complexation approach for formulating microcrystals containing ~50% loading of a protein kinase inhibitor, sunitinib, to enhance survival of RGCs with subconjunctival injection. A single subconjunctival injection of sunitinib-pamoate complex (SPC) microcrystals provided 20 weeks of sustained retina drug levels, leading to neuroprotection in a rat model of optic nerve injury. Furthermore, subconjunctival injection of SPC microcrystals also led to therapeutic effects in a rat model of corneal neovascularization. Importantly, therapeutically relevant retina drug concentrations were achieved with subconjunctival injection of SPC microcrystals in pigs. For a chronic disease such as glaucoma, a formulation that provides sustained therapeutic effects to complement IOP lowering therapies could provide improved disease management and promote patient quality of life.
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12
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Kompella UB, Hartman RR, Patil MA. Extraocular, periocular, and intraocular routes for sustained drug delivery for glaucoma. Prog Retin Eye Res 2021; 82:100901. [PMID: 32891866 PMCID: PMC8317199 DOI: 10.1016/j.preteyeres.2020.100901] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 08/22/2020] [Accepted: 08/30/2020] [Indexed: 02/07/2023]
Abstract
Although once daily anti-glaucoma drug therapy is a current clinical reality, most therapies require multiple dosing and there is an unmet need to develop convenient, safe, and effective sustained release drug delivery systems for long-term treatment to improve patient adherence and outcomes. One of the first sustained release drug delivery systems was approved for the reduction of intraocular pressure in glaucoma patients. It is a polymeric reservoir-type insert delivery system, Ocusert™, placed under the eyelid and on the ocular surface for zero-order drug release over one week. The insert, marketed in two strengths, released pilocarpine on the eye surface. While many clinicians appreciated this drug product, it was eventually discontinued. No similar sustained release non-invasive drug delivery system has made it to the market to date for treating glaucoma. Drug delivery systems under development include punctal plugs, ring-type systems, contact lenses, implants, microspheres, nanospheres, gels, and other depot systems placed in the extraocular, periocular, or intraocular regions including intracameral, supraciliary, and intravitreal spaces. This article discusses the advantages and disadvantages of the various routes of administration and delivery systems for sustained glaucoma therapy. It also provides the reader with some examples and discussion of drug delivery systems that could potentially be applied for glaucoma treatment. Interestingly, one intracamerally injected implant, Durysta™, was approved recently for sustained intraocular pressure reduction. However, long-term acceptance of such devices has yet to be established. The ultimate success of the delivery system will depend on efficacy relative to eye drop dosing, safety, reimbursement options, and patient acceptance. Cautious development efforts are warranted considering prior failed approaches for sustained glaucoma drug delivery. Neuroprotective approaches for glaucoma therapy including cell, gene, protein, and drug-combination therapies, mostly administered intravitreally, are also rapidly progressing towards assessment in humans.
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Affiliation(s)
- Uday B Kompella
- Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO, USA; Department of Ophthalmology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA; Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, USA; Colorado Center for Nanomedicine and Nanosafety, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
| | - Rachel R Hartman
- Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Madhoosudan A Patil
- Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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Smith SM, Salmon JH, Abbaraju S, Amin R, Gilger BC. Tolerability, pharmacokinetics, and pharmacodynamics of a brinzolamide episcleral sustained release implant in normotensive New Zealand white rabbits. J Drug Deliv Sci Technol 2021. [DOI: 10.1016/j.jddst.2020.102123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Parikh KS, Josyula A, Omiadze R, Ahn JY, Ha Y, Ensign LM, Hanes J, Pitha I. Nano-structured glaucoma drainage implant safely and significantly reduces intraocular pressure in rabbits via post-operative outflow modulation. Sci Rep 2020; 10:12911. [PMID: 32737340 PMCID: PMC7395089 DOI: 10.1038/s41598-020-69687-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 07/14/2020] [Indexed: 12/21/2022] Open
Abstract
Glaucoma is a leading cause of irreversible vision loss predicted to affect more than 100 million people by 2040. Intraocular pressure (IOP) reduction prevents development of glaucoma and vision loss from glaucoma. Glaucoma surgeries reduce IOP by facilitating aqueous humor outflow through a vent fashioned from the wall of the eye (trabeculectomy) or a glaucoma drainage implant (GDI), but surgeries lose efficacy overtime, and the five-year failure rates for trabeculectomy and tube shunts are 25-45%. The majority of surgical failures occur due to fibrosis around the vent. Alternatively, surgical procedures can shunt aqueous humor too well, leading to hypotony. Electrospinning is an appealing manufacturing platform for GDIs, as it allows for incorporation of biocompatible polymers into nano- or micro-fibers that can be configured into devices of myriad combinations of dimensions and conformations. Here, small-lumen, nano-structured glaucoma shunts were manufactured with or without a degradable inner core designed to modulate aqueous humor outflow to provide immediate IOP reduction, prevent post-operative hypotony, and potentially offer significant, long-term IOP reduction. Nano-structured shunts were durable, leak-proof, and demonstrated biocompatibility and patency in rabbit eyes. Importantly, both designs prevented hypotony and significantly reduced IOP for 27 days in normotensive rabbits, demonstrating potential for clinical utility.
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Affiliation(s)
- Kunal S Parikh
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Center for Bioengineering Innovation & Design, Johns Hopkins University, Baltimore, MD, 21218, USA
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
| | - Aditya Josyula
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Revaz Omiadze
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
| | - Ju Young Ahn
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Youlim Ha
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Laura M Ensign
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Justin Hanes
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Departments of Environmental Health Sciences, Oncology, and Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA
| | - Ian Pitha
- Center for Nanomedicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21231, USA.
- Glaucoma Center of Excellence, Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, 21287, USA.
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Al-Natour MA, Yousif MD, Cavanagh R, Abouselo A, Apebende EA, Ghaemmaghami A, Kim DH, Aylott JW, Taresco V, Chauhan VM, Alexander C. Facile Dye-Initiated Polymerization of Lactide-Glycolide Generates Highly Fluorescent Poly(lactic- co-glycolic Acid) for Enhanced Characterization of Cellular Delivery. ACS Macro Lett 2020; 9:431-437. [PMID: 35648548 DOI: 10.1021/acsmacrolett.9b01014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Poly(lactic-co-glycolic acid) (PLGA) is a versatile synthetic copolymer that is widely used in pharmaceutical applications. This is because it is well-tolerated in the body, and copolymers of varying physicochemical properties are readily available via ring-opening polymerization. However, native PLGA polymers are hard to track as drug delivery carriers when delivered to subcellular spaces, due to the absence of an easily accessible "handle" for fluorescent labeling. Here we show a one-step, scalable, solvent-free, synthetic route to fluorescent blue (2-aminoanthracene), green (5-aminofluorescein), and red (rhodamine-6G) PLGA, in which every polymer chain in the sample is fluorescently labeled. The utility of initiator-labeled PLGA was demonstrated through the preparation of nanoparticles, capable of therapeutic subcellular delivery to T-helper-precursor-1 (THP-1) macrophages, a model cell line for determining in vitro biocompatibility and particle uptake. Super resolution confocal fluorescence microscopy imaging showed that dye-initiated PLGA nanoparticles were internalized to punctate regions and retained bright fluorescence over at least 24 h. In comparison, PLGA nanoparticles with 5-aminofluorescein introduced by conventional nanoprecipitation/encapsulation showed diffuse and much lower fluorescence intensity in the same cells and over the same time periods. The utility of this approach for in vitro drug delivery experiments was demonstrated through the concurrent imaging of the fluorescent drug doxorubicin (λex = 480 nm, λem = 590 nm) with carrier 5-aminofluorescein PLGA, also in THP-1 cells, in which the intracellular locations of the drug and the polymer could be clearly visualized. Finally, the dye-labeled particles were evaluated in an in vivo model, via delivery to the nematode Caenorhabditis elegans, with bright fluorescence again apparent in the internal tract after 3 h. The results presented in this manuscript highlight the ease of synthesis of highly fluorescent PLGA, which could be used to augment tracking of future therapeutics and accelerate in vitro and in vivo characterization of delivery systems prior to clinical translation.
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Affiliation(s)
- Mohammad A. Al-Natour
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham NG7 2RD, United Kingdom
- Division of Immunology, School of Life Sciences, Faculty of Medicine and Health Sciences, Queen’s Medical Centre, University of Nottingham, Nottingham, United Kingdom
- The Faculty of Pharmacy and Medical Sciences, University of Petra, Amman, Jordan
| | - Mohamed D. Yousif
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Robert Cavanagh
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Amjad Abouselo
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Edward A. Apebende
- School of Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Amir Ghaemmaghami
- Division of Immunology, School of Life Sciences, Faculty of Medicine and Health Sciences, Queen’s Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Dong-Hyun Kim
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Jonathan W. Aylott
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Vincenzo Taresco
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham NG7 2RD, United Kingdom
- School of Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Veeren M. Chauhan
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Cameron Alexander
- School of Pharmacy, Boots Science Building, University of Nottingham, Nottingham NG7 2RD, United Kingdom
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Abstract
Glaucoma is the second leading cause of blindness worldwide. Even though significant advances have been made in its management, currently available antiglaucoma therapies suffer from considerable drawbacks. Typically, the success and efficacy of glaucoma medications are undermined by their limited bioavailability to target tissues and the inadequate adherence demonstrated by patients with glaucoma. The latter is due to a gradual decrease in tolerability of lifelong topical therapies and the significant burden to patients of prescribed stepwise antiglaucoma regimens with frequent dosing which impact quality of life. On the other hand, glaucoma surgery is restricted by the inability of antifibrotic agents to efficiently control the wound healing process without causing severe collateral damage and long-term complications. Evolution of the treatment paradigm for patients with glaucoma will ideally include prevention of retinal ganglion cell degeneration by the successful delivery of neurotrophic factors, anti-inflammatory drugs, and gene therapies. Nanotechnology-based treatments may surpass the limitations of currently available glaucoma therapies through optimized targeted drug delivery, increased bioavailability, and controlled release. This review addresses the recent advances in glaucoma treatment strategies employing nanotechnology, including medical and surgical management, neuroregeneration, and neuroprotection.
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Supuran CT, Altamimi ASA, Carta F. Carbonic anhydrase inhibition and the management of glaucoma: a literature and patent review 2013-2019. Expert Opin Ther Pat 2019; 29:781-792. [PMID: 31596641 DOI: 10.1080/13543776.2019.1679117] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Introduction: Glaucoma affects more than 70 million people worldwide. One of the major therapeutic options for its management is based on the inhibition of the metalloenzyme carbonic anhydrases (CAs, EC 4.2.1.1). CA inhibitors (CAIs) diminish ocular hypertension in glaucomatous patients by reducing the rate of bicarbonate formation and thus, the secretion of the aqueous humor. Areas covered: This review is intended to cover the major contributions in terms of patent literature reports for the treatment of ophthalmic diseases by means of CAIs in a time frame spanning from 2013 to date. Expert opinion: The patent literature is dominated by innovative pharmaceutical formulations including a CAI alone or in combination with other therapeutic agents. Very few novelties within drug discovery are currently present and they mainly account for new CAI moieties and classical CAIs merged into scaffolds bearing additional chemical functionalities beneficial for the pharmacological treatment of the disease. It is reasonable to expect that in the near future the so-called 'old drugs' will achieve pharmacological performances in the management of ocular hypertension beyond any expectations and thus open a new era of drug repurposing merely based on material science advancements.
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Affiliation(s)
- Claudiu T Supuran
- NEUROFARBA Department, Sezione di Scienze Farmaceutiche e Nutraceutiche, University of Florence , Sesto Fiorentino (Florence) , Italy
| | | | - Fabrizio Carta
- NEUROFARBA Department, Sezione di Scienze Farmaceutiche e Nutraceutiche, University of Florence , Sesto Fiorentino (Florence) , Italy
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Ristroph KD, Prud'homme RK. Hydrophobic ion pairing: encapsulating small molecules, peptides, and proteins into nanocarriers. NANOSCALE ADVANCES 2019; 1:4207-4237. [PMID: 33442667 PMCID: PMC7771517 DOI: 10.1039/c9na00308h] [Citation(s) in RCA: 123] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 09/18/2019] [Indexed: 05/26/2023]
Abstract
Hydrophobic ion pairing has emerged as a method to modulate the solubility of charged hydrophilic molecules ranging in class from small molecules to large enzymes. Charged hydrophilic molecules are ionically paired with oppositely-charged molecules that include hydrophobic moieties; the resulting uncharged complex is water-insoluble and will precipitate in aqueous media. Here we review one of the most prominent applications of hydrophobic ion pairing: efficient encapsulation of charged hydrophilic molecules into nano-scale delivery vehicles - nanoparticles or nanocarriers. Hydrophobic complexes are formed and then encapsulated using techniques developed for poorly-water-soluble therapeutics. With this approach, researchers have reported encapsulation efficiencies up to 100% and drug loadings up to 30%. This review covers the fundamentals of hydrophobic ion pairing, including nomenclature, drug eligibility for the technique, commonly-used counterions, and drug release of encapsulated ion paired complexes. We then focus on nanoformulation techniques used in concert with hydrophobic ion pairing and note strengths and weaknesses specific to each. The penultimate section bridges hydrophobic ion pairing with the related fields of polyelectrolyte coacervation and polyelectrolyte-surfactant complexation. We then discuss the state of the art and anticipated future challenges. The review ends with comprehensive tables of reported hydrophobic ion pairing and encapsulation from the literature.
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Affiliation(s)
- Kurt D. Ristroph
- Department of Chemical and Biological Engineering, Princeton UniversityPrincetonNew Jersey 08544USA
| | - Robert K. Prud'homme
- Department of Chemical and Biological Engineering, Princeton UniversityPrincetonNew Jersey 08544USA
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Samy KE, Cao Y, Kim J, Konichi da Silva NR, Phone A, Bloomer MM, Bhisitkul RB, Desai TA. Co-Delivery of Timolol and Brimonidine with a Polymer Thin-Film Intraocular Device. J Ocul Pharmacol Ther 2019; 35:124-131. [PMID: 30615539 PMCID: PMC6450452 DOI: 10.1089/jop.2018.0096] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 11/08/2018] [Indexed: 12/30/2022] Open
Abstract
PURPOSE We developed a polycaprolactone (PCL) co-delivery implant that achieves zero-order release of 2 ocular hypotensive agents, timolol maleate and brimonidine tartrate. We also demonstrate intraocular pressure (IOP)-lowering effects of the implant for 3 months in vivo. METHODS Two PCL thin-film compartments were attached to form a V-shaped co-delivery device using film thicknesses of ∼40 and 20 μm for timolol and brimonidine compartments, respectively. In vitro release kinetics were measured in pH- and temperature-controlled fluid chambers. Empty or drug-loaded devices were implanted intracamerally in normotensive rabbits for up to 13 weeks with weekly measurements of IOP. For ocular concentrations, rabbits were euthanized at 4, 8, or 13 weeks, aqueous fluid was collected, and ocular tissues were dissected. Drug concentrations were measured by liquid chromatography-tandem mass spectrometry. RESULTS In vitro studies show zero-order release kinetics for both timolol (1.75 μg/day) and brimonidine (0.48 μg/day) for up to 60 days. In rabbit eyes, the device achieved an average aqueous fluid concentration of 98.1 ± 68.3 ng/mL for timolol and 5.5 ± 3.6 ng/mL for brimonidine. Over 13 weeks, the drug-loaded co-delivery device resulted in a statistically significant cumulative reduction in IOP compared to untreated eyes (P < 0.05) and empty-device eyes (P < 0.05). CONCLUSIONS The co-delivery device demonstrated a zero-order release profile in vitro for 2 hypotensive agents over 60 days. In vivo, the device led to significant cumulative IOP reduction of 3.4 ± 1.6 mmHg over 13 weeks. Acceptable ocular tolerance was seen, and systemic drug levels were unmeasurable.
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Affiliation(s)
- Karen E. Samy
- UC Berkeley-UCSF Graduate Program in Bioengineering, San Francisco, California
| | - Yiqi Cao
- UC Berkeley-UCSF Graduate Program in Bioengineering, San Francisco, California
| | - Jean Kim
- UC Berkeley-UCSF Graduate Program in Bioengineering, San Francisco, California
| | | | - Audrey Phone
- Department of Ophthalmology, University of California, San Francisco, San Francisco, California
| | - Michele M. Bloomer
- Department of Ophthalmology, University of California, San Francisco, San Francisco, California
| | - Robert B. Bhisitkul
- Department of Ophthalmology, University of California, San Francisco, San Francisco, California
| | - Tejal A. Desai
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, California
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Controlled release of corticosteroid with biodegradable nanoparticles for treating experimental autoimmune uveitis. J Control Release 2019; 296:68-80. [PMID: 30660629 DOI: 10.1016/j.jconrel.2019.01.018] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 01/07/2019] [Accepted: 01/15/2019] [Indexed: 12/30/2022]
Abstract
Noninfectious uveitis is a potentially blinding ocular condition that often requires treatment with corticosteroids to prevent inflammation-related ocular complications. Severe forms of uveitis such as panuveitis that affects the whole eye often require a combination of topical and either regional or systemic corticosteroid. Regional corticosteroids are currently delivered inside the eye by intravitreal injection (e.g. Ozurdex®, an intravitreal dexamethasone implant). Intravitreal injection is associated with rare but potentially serious side effects, including endophthalmitis, retinal and vitreous hemorrhage, and retinal detachment. Subconjunctival (SCT) injection is a less invasive option that is a common route used for post-surgical drug administration and treatment of infection and severe inflammation. However, it is the water soluble form of dexamethasone, dexamethasone sodium phosphate (DSP), that has been demonstrated to achieve high intraocular penetration with subconjunctival injection. It is difficult to load highly water soluble drugs, such as DSP, and achieve sustained drug release using conventional encapsulation methods. We found that use of carboxyl-terminated poly(lactic-co-glycolic acid) (PLGA) allowed encapsulation of DSP into biodegradable nanoparticles (NP) with relatively high drug content (6% w/w) if divalent zinc ions were used as an ionic "bridge" between the PLGA and DSP. DSP-Zn-NP had an average diameter of 210 nm, narrow particle size distribution (polydispersity index ~0.1), and near neutral surface charge (-9 mV). DSP-Zn-NP administered by SCT injection provided detectable DSP levels in both the anterior chamber and vitreous chamber of the eye for at least 3 weeks. In a rat model of experimental autoimmune uveitis (EAU), inflammation was significantly reduced in both the front and back of the eye in animals that received a single SCT injection of DSP-Zn-NP as compared to animals that received either aqueous DSP solution or phosphate buffered saline (PBS). DSP-Zn-NP efficacy was evidenced by a reduced clinical disease score, decreased expression of various inflammatory cytokines, and preserved retinal structure and function. Furthermore, SCT DSP-Zn-NP significantly reduced microglia cell density in the retina, a hallmark of EAU in rats. DSP-Zn-NP hold promise as a new strategy to treat noninfectious uveitis and potentially other ocular inflammatory disorders.
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Abstract
OBJECTIVES Ocular surface disease frequently coexists with glaucoma and may be initiated or exacerbated by topical glaucoma medications. We performed a review of current literature to assess the prevalence, causes, and treatment of ocular surface disease in glaucoma patients, specifically those on topical therapy. METHODS A Pubmed database search was conducted. A total of 720 articles published from 1972 to 2018 were found in relation with ocular surface disease, glaucoma, and glaucoma medications. Of these, 102 articles were included in this analysis. We included primary and empirical studies for patients on topical glaucoma medications. Exclusion criteria included case reports, non-English studies, and articles unrelated to the primary subject of this review. RESULTS Ocular surface disease among normal and glaucomatous eyes was evaluated based on diagnostic testing including clinical examination and questionnaires to determine visual function and quality of life. Glaucoma medications can be associated with toxicities to the ocular surface, most often due to the nature of the preservative included in the medication; however, the incidence of toxicity can be mitigated by the use of preservative free medications, decreased preservative medications, or treatment of dry eye disease. Treatment of glaucoma with laser trabeculoplasty or minimally invasive glaucoma surgeries that spare the conjunctiva and the cornea may avoid or decrease reliance on topical glaucoma medications, potentially avoiding the initiation or progression of ocular surface disease. CONCLUSIONS Recognition and treatment of ocular surface disease in glaucoma patients may improve patient quality of life and medication adherence. This may ultimately improve glaucoma treatment outcomes.
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Srinivasarao DA, Lohiya G, Katti DS. Fundamentals, challenges, and nanomedicine‐based solutions for ocular diseases. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2018; 11:e1548. [DOI: 10.1002/wnan.1548] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 09/21/2018] [Accepted: 10/28/2018] [Indexed: 01/07/2023]
Affiliation(s)
- Dadi A. Srinivasarao
- Department of Biological Sciences and Bioengineering Indian Institute of Technology Kanpur Kanpur India
| | - Garima Lohiya
- Department of Biological Sciences and Bioengineering Indian Institute of Technology Kanpur Kanpur India
| | - Dhirendra S. Katti
- Department of Biological Sciences and Bioengineering Indian Institute of Technology Kanpur Kanpur India
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Basu A, Domb AJ. Recent Advances in Polyanhydride Based Biomaterials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1706815. [PMID: 29707879 DOI: 10.1002/adma.201706815] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 01/18/2018] [Indexed: 06/08/2023]
Abstract
This review focusses on recent developments of polyanhydrides, a class of degradable synthetic biopolymers. Polyanhydrides have been used as carriers for controlled delivery of drugs. A polyanhydride copolymer of carboxyphenoxy propane and sebacic acid has been used in Gliadel brain tumor implants for the controlled delivery of carmustine or bis-chloroethylnitrosourea. They are easy and inexpensive to synthesize (especially scale up). However, polyanhydrides possess a short shelf-life. Hydrolytic cleavage and anhydride interchanges lower their molecular weights during storage. One of the highlights in recent developments of polyanhydride chemistry is the discovery of alternating copolymers having extended shelf-life. Other highlights include their applications in biomedical electronics, vaccine delivery, and nano/micro particulate delivery systems. This review examines approaches for polyanhydride synthesis followed by their recent developments in biomedical applications.
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Affiliation(s)
- Arijit Basu
- School of Pharmacy - Faculty of Medicine, The Hebrew University of Jerusalem, Hadassah Ein Kerem Medical Center Campus, Jerusalem, 91120, Israel
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Room No. 617, 500, Main Street, MA, 02131, USA
| | - Abraham J Domb
- School of Pharmacy - Faculty of Medicine, The Hebrew University of Jerusalem, Hadassah Ein Kerem Medical Center Campus, Jerusalem, 91120, Israel
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Improved delivery of PLGA microparticles and microparticle-cell scaffolds in clinical needle gauges using modified viscosity formulations. Int J Pharm 2018; 546:272-278. [PMID: 29753905 DOI: 10.1016/j.ijpharm.2018.05.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 05/08/2018] [Accepted: 05/09/2018] [Indexed: 01/06/2023]
Abstract
Polymer microparticles are widely used as acellular drug delivery platforms in regenerative medicine, and have emerging potential as cellular scaffolds for therapeutic cell delivery. In the clinic, PLGA microparticles are typically administered intramuscularly or subcutaneously, with the clinician and clinical application site determining the precise needle gauge used for delivery. Here, we explored the role of needle diameter in microparticle delivery yield, and develop a modified viscosity formulation to improve microparticle delivery across a range of clinically relevant needle diameters. We have identified an optimal biocompatible formulation containing 0.25% pluronic F127 and 0.25% carboxymethyl cellulose, which can increase delivery payload to 520% across needle gauges 21-30G, and note that needle diameter impacts delivery efficacy. We use this formulation to increase the delivery yield of PLGA microparticles, and separately, PLGA-cell scaffolds supporting viable mesenchymal stem cells (MSCs), demonstrating the first in vitro delivery of this cell scaffold system. Together, these results highlight an optimal formulation for the delivery of microparticle and microparticle-cell scaffolds, and illustrate how careful choice of delivery formulation and needle size can dramatically impact delivery payload.
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25
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Pitha I, Kimball EC, Oglesby EN, Pease ME, Fu J, Schaub J, Kim YC, Hu Q, Hanes J, Quigley HA. Sustained Dorzolamide Release Prevents Axonal and Retinal Ganglion Cell Loss in a Rat Model of IOP-Glaucoma. Transl Vis Sci Technol 2018; 7:13. [PMID: 29616152 PMCID: PMC5879766 DOI: 10.1167/tvst.7.2.13] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/21/2017] [Indexed: 01/13/2023] Open
Abstract
Purpose To determine if one injection of a sustained release formulation of dorzolamide in biodegradable microparticles (DPP) reduces retinal ganglion cell (RGC) loss in a rat model of glaucoma. Methods We injected either DPP or control microparticles intravitreally in rats. Two days later, unilateral ocular hypertension was induced by translimbal, diode laser treatment by a surgeon masked to treatment group. IOP and clinical exams were performed until sacrifice 6 weeks after laser treatment. RGC loss was measured by masked observers in both optic nerve cross-sections and RGC layer counts from retinal whole mounts. Results Cumulative IOP exposure was significantly reduced by DPP injection (49 ± 48 mm Hg × days in treated versus 227 ± 191 mm Hg × days in control microparticle eyes; P = 0.012, t-test). While control-injected eyes increased in axial length by 2.4 ± 1.7%, DPP eyes did not significantly enlarge (0.3 ± 2.2%, difference from control, P = 0.03, t-test). RGC loss was significantly less in DPP eyes compared with control microparticle injection alone (RGC axon count reduction: 21% vs. 52%; RGC body reduction: 25% vs. 50% [beta tubulin labeling]; P = 0.02, t-test). Conclusions A single injection of sustained release DPP protected against RGC loss and axial elongation in a rat model of IOP glaucoma. Translational Relevance Sustained release IOP-lowering medications have the potential to stop glaucoma progression.
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Affiliation(s)
- Ian Pitha
- Department of Ophthalmology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Center for Nanomedicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Glaucoma Center of Excellence, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Elizabeth C Kimball
- Glaucoma Center of Excellence, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ericka N Oglesby
- Glaucoma Center of Excellence, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Mary Ellen Pease
- Glaucoma Center of Excellence, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jie Fu
- Department of Ophthalmology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Center for Nanomedicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Julie Schaub
- Glaucoma Center of Excellence, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yoo-Chun Kim
- Department of Ophthalmology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Center for Nanomedicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Qi Hu
- Department of Ophthalmology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Center for Nanomedicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Justin Hanes
- Department of Ophthalmology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Center for Nanomedicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Harry A Quigley
- Department of Ophthalmology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Center for Nanomedicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Glaucoma Center of Excellence, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Li L, Chen LP, Liu QH. Effect of the Notch signaling pathway on retinal ganglion cells and its neuroprotection in rats with acute ocular hypertension. Int J Ophthalmol 2018; 11:208-215. [PMID: 29487808 DOI: 10.18240/ijo.2018.02.05] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 01/03/2018] [Indexed: 01/14/2023] Open
Abstract
AIM To explore the effect of the Notch signaling pathway on retinal ganglion cells (RGCs) and optic nerve in rats with acute ocular hypertension (OH). METHODS Totally 48 Sprague-Dawley (SD) rats were included, among which 36 rats were selected to establish acute OH models. OH rats received a single intravitreal injection of 2 µL phosphate buffered solution (PBS) and another group of OH rats received a single intravitreal injection of 10 µmol/L γ-secretase inhibitor (DAPT). Quantitative real-time polymerase chain reaction (qPCR) and Western blot assay were adopted to determine the mRNA level of Notch and the protein levels of Notch, Bcl-2, Bax, caspase-3, and growth-associated protein 43 (GAP-43). The RGC apoptosis conditions were assessed by TUNEL staining. RESULTS The OH rats and PBS-injected rats had increased expression levels of Notch1, Bax, caspase-3, and GAP-43, decreased expression levels of Bcl-2, and increased RGC apoptosis, with severer macular edema and RGCs more loosely aligned, when compared with the normal rats. The DAPT-treated rats displayed increased expression levels of Notch1, Bax, caspase-3, and GAP-43, decreased expression levels of Bcl-2, and increased RGC apoptosis, in comparison with the OH rats and PBS-injected rats. RGCs were hardly observed and macular edema became severe in the DAPT-treated rat. CONCLUSION The Notch signaling pathway may suppress the apoptosis of retinal ganglion cells and enhances the regeneration of the damaged optic nerves in rats with acute OH.
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Affiliation(s)
- Lei Li
- Department of Ophthalmology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China.,Department of Ophthalmology, the First Affiliated Hospital of Hainan Medical University, Haikou 570102, Hainan Province, China
| | - Li-Ping Chen
- Department of Ophthalmology, the First Affiliated Hospital of Hainan Medical University, Haikou 570102, Hainan Province, China
| | - Qing-Huai Liu
- Department of Ophthalmology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
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Zhao GL, Li RZ, Pang YH, Wang XQ, Peng HJ, Wei JF, Zhou Z. Diagnostic Function of 3D Optical Coherence Tomography Images in Diagnosis of Vogt-Koyanagi-Harada Disease at Acute Uveitis Stage. Med Sci Monit 2018; 24:687-697. [PMID: 29396390 PMCID: PMC5807914 DOI: 10.12659/msm.905931] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 07/06/2017] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND This study analyzed the macular 3D-OCT images of Vogt-Koyanagi-Harada disease (VKH) in uveitis, explored the characteristics of 3D-OCT images of the macular region of VKH, and assessed which characteristics contribute most to VKH diagnosis. MATERIAL AND METHODS The 3D-OCT examination of 25 cases of VKH was performed on the macular area, and the image characteristics were analyzed. RESULTS Our study included a total of 50 eyes from 25 cases of VKH patients, 10 males and 15 females, aged 17 to 64 years, mean (39.44±11.60) years old. According to OCT B-scan images, 49 (98%) eyes had ERD, 49 (98%) eyes had nerve retinal edema, 36 (72%) eyes had endometrium-like structure (including cysts), 5 (10%) eyes had RPE folds, 35 (70%) eyes had changes in the internal septum, 49 (98%) eyes had RPE monolayer structure outside the ERD region. In ILM-RPE thickness, 49 (98%) eyes had retinal irregular thickening and 31 (62%) eyes had radial stripe changes. In ILM contour figure, 50 eyes (100%) showed exceptional uplift, 5 (10%) eyes had small focal uplift for PED on the RPE surface, and 48 (96%) eyes had wavy ups and downs. CONCLUSIONS In OCT B-scan imaging, the ERT, retinal edema of the retina, and the RPE monolayer structure outside the range are most likely to occur in VKH. The ILM-RPE thickness chart in 3D reconstruction showed irregular thickening of the retina. The ILM contour graph showed abnormal uplift, and RPE surface wavy ups and downs in VKH most likely to occur.
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Schehlein EM, Novack G, Robin AL. New pharmacotherapy for the treatment of glaucoma. Expert Opin Pharmacother 2017; 18:1939-1946. [PMID: 29172818 DOI: 10.1080/14656566.2017.1408791] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Glaucoma is the second leading cause of blindness in the world and current pharmacotherapies for glaucoma have remained relatively unchanged (with the exception of fixed combinations of previously available medications) since the mid-1990s with the development of prostaglandin analogues. Now, with both new formulations and new classes of medications with novel mechanisms of action, the medical therapy of glaucoma may be heralding a new dawn in medical management. Areas covered: This review outlines new topical therapies for intraocular pressure (IOP) lowering treatment, in addition to new formulations, preservative-free options, and advances in glaucoma medical therapy delivery. We performed a comprehensive search for published studies for glaucoma medical therapy using the electronic database PubMed. A manual search for each therapy or delivery system was also performed. Expert commentary: These advances in glaucoma therapy have the potential to overcome many barriers to glaucoma's medical care, particularly in terms of adherence. However, both time and research are needed to prove the relative efficacy and safety of these new pharmacotherapies and products, helping us decide their role in the treatment of elevated intraocular pressure. We are hopeful that these new developments in therapy may bring more options for glaucoma medical therapy.
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Affiliation(s)
- Emily M Schehlein
- a Department of Ophthalmology and Visual Sciences , University of Michigan , Ann Arbor , MI , USA
| | - Gary Novack
- b PharmaLogic Development Inc ., San Rafael , CA , USA.,c Departments of Pharmacology and Ophthalmology , University of California, Davis, School of Medicine , Sacramento , CA , USA
| | - Alan L Robin
- a Department of Ophthalmology and Visual Sciences , University of Michigan , Ann Arbor , MI , USA.,d Department of Ophthalmology and School of Public Health , Johns Hopkins University , Baltimore , MD , USA
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Toris CB, Gelfman C, Whitlock A, Sponsel WE, Rowe-Rendleman CL. Making Basic Science Studies in Glaucoma More Clinically Relevant: The Need for a Consensus. J Ocul Pharmacol Ther 2017; 33:501-518. [PMID: 28777040 DOI: 10.1089/jop.2017.0001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Glaucoma is a chronic, progressive, and debilitating optic neuropathy that causes retinal damage and visual defects. The pathophysiologic mechanisms of glaucoma remain ill-defined, and there is an indisputable need for contributions from basic science researchers in defining pathways for translational research. However, glaucoma researchers today face significant challenges due to the lack of a map of integrated pathways from bench to bedside and the lack of consensus statements to guide in choosing the right research questions, techniques, and model systems. Here, we present the case for the development of such maps and consensus statements, which are critical for faster development of the most efficacious glaucoma therapy. We underscore that interrogating the preclinical path of both successful and unsuccessful clinical programs is essential to defining future research. One aspect of this is evaluation of available preclinical research tools. To begin this process, we highlight the utility of currently available animal models for glaucoma and emphasize that there is a particular need for models of glaucoma with normal intraocular pressure. In addition, we outline a series of discoveries from cell-based, animal, and translational research that begin to reveal a map of glaucoma from cell biology to physiology to disease pathology. Completion of these maps requires input and consensus from the global glaucoma research community. This article sets the stage by outlining various approaches to such a consensus. Together, these efforts will help accelerate basic science research, leading to discoveries with significant clinical impact for people with glaucoma.
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Affiliation(s)
- Carol B Toris
- 1 Department of Ophthalmology and Visual Sciences, Case Western Reserve University , Cleveland, Ohio
| | | | | | - William E Sponsel
- 3 WESMD Professional Association , San Antonio, Texas.,4 Department of Biomedical Engineering, University of Texas San Antonio , San Antonio, Texas.,5 Department of Vision Sciences, University of the Incarnate Word , San Antonio, Texas
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Abstract
PURPOSE OF REVIEW Sustained drug delivery has been recognized as a need for patients with ocular hypertension or glaucomatous optic neuropathy. Several sustained drug delivery systems and devices are currently on the horizon. This review aims to summarize initial results with these platforms, as reported in the literature, and also provide insight into their possible role in the glaucoma treatment paradigm. RECENT FINDINGS Sustained drug delivery systems currently on the horizon include the topical bimatoprost ocular insert, travoprost and latanoprost punctal plugs, latanoprost-eluting contact lenses, bimatoprost and travoprost intraocular implants, as well as several other therapies in earlier stages of development. Delivery strategies differ with respect to ocular site of implantation, ocular hypotensive agent, and duration of efficacy. Efficacy and safety outcomes with these devices are favorable thus far. SUMMARY The glaucoma treatment paradigm is currently in a state of flux as sustained drug delivery systems bring promise to individuals suffering from ocular hypertension or glaucoma. Several options will likely become available in the near future to ease the burden of daily administration of chronic therapy with intraocular pressure-lowering agents.
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Szigiato AA, Podbielski DW, Ahmed IIK. Sustained drug delivery for the management of glaucoma. EXPERT REVIEW OF OPHTHALMOLOGY 2017. [DOI: 10.1080/17469899.2017.1280393] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
| | - Dominik W. Podbielski
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada
| | - Iqbal Ike K. Ahmed
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada
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