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Del Amo EM, Rimpelä AK, Heikkinen E, Kari OK, Ramsay E, Lajunen T, Schmitt M, Pelkonen L, Bhattacharya M, Richardson D, Subrizi A, Turunen T, Reinisalo M, Itkonen J, Toropainen E, Casteleijn M, Kidron H, Antopolsky M, Vellonen KS, Ruponen M, Urtti A. Pharmacokinetic aspects of retinal drug delivery. Prog Retin Eye Res 2016; 57:134-185. [PMID: 28028001 DOI: 10.1016/j.preteyeres.2016.12.001] [Citation(s) in RCA: 398] [Impact Index Per Article: 49.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 11/25/2016] [Accepted: 12/01/2016] [Indexed: 12/14/2022]
Abstract
Drug delivery to the posterior eye segment is an important challenge in ophthalmology, because many diseases affect the retina and choroid leading to impaired vision or blindness. Currently, intravitreal injections are the method of choice to administer drugs to the retina, but this approach is applicable only in selected cases (e.g. anti-VEGF antibodies and soluble receptors). There are two basic approaches that can be adopted to improve retinal drug delivery: prolonged and/or retina targeted delivery of intravitreal drugs and use of other routes of drug administration, such as periocular, suprachoroidal, sub-retinal, systemic, or topical. Properties of the administration route, drug and delivery system determine the efficacy and safety of these approaches. Pharmacokinetic and pharmacodynamic factors determine the required dosing rates and doses that are needed for drug action. In addition, tolerability factors limit the use of many materials in ocular drug delivery. This review article provides a critical discussion of retinal drug delivery, particularly from the pharmacokinetic point of view. This article does not include an extensive review of drug delivery technologies, because they have already been reviewed several times recently. Instead, we aim to provide a systematic and quantitative view on the pharmacokinetic factors in drug delivery to the posterior eye segment. This review is based on the literature and unpublished data from the authors' laboratory.
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Affiliation(s)
- Eva M Del Amo
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Anna-Kaisa Rimpelä
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Emma Heikkinen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Otto K Kari
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Eva Ramsay
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Tatu Lajunen
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Mechthild Schmitt
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Laura Pelkonen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Madhushree Bhattacharya
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Dominique Richardson
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Astrid Subrizi
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Tiina Turunen
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Mika Reinisalo
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Jaakko Itkonen
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Elisa Toropainen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Marco Casteleijn
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Heidi Kidron
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Maxim Antopolsky
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | | | - Marika Ruponen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Arto Urtti
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland; School of Pharmacy, University of Eastern Finland, Kuopio, Finland.
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Lajunen T, Nurmi R, Kontturi L, Viitala L, Yliperttula M, Murtomäki L, Urtti A. Light activated liposomes: Functionality and prospects in ocular drug delivery. J Control Release 2016; 244:157-166. [PMID: 27565215 DOI: 10.1016/j.jconrel.2016.08.024] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 08/08/2016] [Accepted: 08/21/2016] [Indexed: 12/17/2022]
Abstract
Ocular drug delivery, especially to the retina and choroid, is a major challenge in drug development. Liposome technology may be useful in ophthalmology in enabling new routes of delivery, prolongation of drug action and intracellular drug delivery, but drug release from the liposomes should be controlled. For that purpose, light activation may be an approach to release drug at specified time and site in the eye. Technical advances have been made in the field of light activated drug release, particularly indocyanine green loaded liposomes are a promising approach with safe materials and effective light triggered release of small and large molecules. This review discusses the liposomal drug delivery with light activated systems in the context of ophthalmic drug delivery challenges.
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Affiliation(s)
- Tatu Lajunen
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Viikinkaari 5 E, 00790 Helsinki, Finland
| | - Riikka Nurmi
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Viikinkaari 5 E, 00790 Helsinki, Finland
| | - Leena Kontturi
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Viikinkaari 5 E, 00790 Helsinki, Finland; Department of Pharmaceutics, University of Utrecht, Utrecht, The Netherlands
| | - Lauri Viitala
- Department of Chemistry, Aalto University, Espoo, Finland
| | - Marjo Yliperttula
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Viikinkaari 5 E, 00790 Helsinki, Finland; Department of Pharmaceutical Sciences, University of Padova, Padova, Italy
| | | | - Arto Urtti
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Viikinkaari 5 E, 00790 Helsinki, Finland; School of Pharmacy, University of Eastern Finland, 70211 Kuopio, Finland.
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Wang S, Mahesh SP, Liu J, Geist C, Zderic V. Focused ultrasound facilitated thermo-chemotherapy for targeted retinoblastoma treatment: A modeling study. Exp Eye Res 2012; 100:17-25. [DOI: 10.1016/j.exer.2012.04.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Revised: 04/13/2012] [Accepted: 04/19/2012] [Indexed: 12/30/2022]
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Abstract
BACKGROUND Intravitreal injection (IVI) with administration of various pharmacological agents is a mainstay of treatment in ophthalmology for endopthalmitis, viral retinitis, age-related macular degeneration, cystoid macular edema, diabetic retinopathy, uveitis, vascular occlusions, and retinal detachment. The indications and therapeutic agents are reviewed in this study. METHODS A search of the English, German, and Spanish language MEDLINE database was conducted. A total of 654 references spanning the period through early 2008 were individually evaluated. RESULTS The advantage of the IVI technique is the ability to maximize intraocular levels of medications and to avoid the toxicities associated with systemic treatment. Intravitreal injection has been used to deliver several types of pharmacological agents into the vitreous cavity: antiinfective and antiinflammatory medications, immunomodulators, anticancer agents, gas, antivascular endothelial growth factor, and several others. The goal of this review is to provide a detailed description of the properties of numerous therapeutic agents that can be delivered through IVI, potential complications of the technique, and recommendations to avoid side effects. CONCLUSION The IVI technique is a valuable tool that can be tailored to the disease process of interest based on the pharmacological agent selected. This review provides the reader with a comprehensive summary of the IVI technique and its multitude of uses.
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Affiliation(s)
- Gholam A Peyman
- Department of Ophthalmology and Vision Science, College of Medicine, University of Arizona, Tucson, Arizona 85351, USA.
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5
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Niesman MR, Khoobehi B, Magin RL, Webb AG. Liposomes and diagnostic imaging: the potential to visualize both structure and function. J Liposome Res 2008. [DOI: 10.3109/08982109409018597] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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6
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Literature Alerts. J Microencapsul 2008. [DOI: 10.3109/02652048909098028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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7
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Abstract
Drug delivery to the eye is hampered by anatomical factors, including the corneal epithelium, the blood-aqueous barrier and the blood-retinal barrier. This review aims to outline the major routes of ocular drug delivery, including systemic, topical, periocular and intravitreal. The pharmacokinetics, the disadvantages and the clinical relevance of these drug delivery routes have been emphasised. Recent advances in surgical techniques, therapeutic approaches and material sciences have produced exciting new therapies for ocular diseases. The role of ophthalmic drug formulation in targeting the desired ocular tissue and enhancing drug delivery by the chosen route whilst minimising side effects is also discussed.
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Affiliation(s)
- Deepta Ghate
- Emory University Eye Center, 1365B, Clifton Road, Atlanta, GA 30322, USA
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Abstract
This review outlines the applications of liposomal formulations in ophthalmology. In ophthalmology, liposomes have been used to treat disorders of both the anterior and posterior segments. These include dry eyes, keratitis, corneal transplant rejection, uveitis, endophthalmitis, and proliferative vitreoretinopathy. Liposomes also have shown promise as vectors for genetic transfection and monoclonal antibody-directed vehicles. Furthermore, heat-activated liposomes have spurred research in focal laser and heat-induced release of liposomal drugs and dyes for selective drug delivery. These techniques have been useful in selective tumor and neovascular vessel occlusion, angiography, and retinal and choroidal blood-flow studies. Although verteporfin is the only liposomal drug currently approved for use in the eye, the benefits of liposomes will likely be applied widely in all treatment, diagnostic, and research aspects of ophthalmology in the future.
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Affiliation(s)
- Shehab Ebrahim
- Department of Ophthalmology, Tulane University Health Sciences Center, New Orleans, LA 70112, USA
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Lee PJ, Peyman GA. Visualization of the retinal and choroidal microvasculature by fluorescent liposomes. Methods Enzymol 2004; 373:214-33. [PMID: 14714406 DOI: 10.1016/s0076-6879(03)73014-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Affiliation(s)
- Paul J Lee
- Tulane University Medical Center, 1430 Tulane Avenue, New Orleans, Louisiana 70112, USA
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Chung JE, Yokoyama M, Okano T. Inner core segment design for drug delivery control of thermo-responsive polymeric micelles. J Control Release 2000; 65:93-103. [PMID: 10699274 DOI: 10.1016/s0168-3659(99)00242-4] [Citation(s) in RCA: 306] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Modification of the thermo-responsive behavior of polymeric micelles for specific drug delivery functions was investigated using combinations of micellar inner cores and outer shell polymer chemistries. Polymeric micelles comprised of AB block copolymers of PIPAAm (poly(N-isopropylacrylamide)) with either PBMA (poly(butyl methacrylate)) or PSt (polystyrene) were employed. PIPAAm-PBMA and PIPAAm-PSt block copolymers formed a core-shell micellar structure after dialysis of the block copolymer solutions in organic solvents against water at 20 degrees C. The hydrophobic drug, adriamycin, (ADR) was loaded into the inner core of the polymeric micelles by dialysis. The polymers showed reversible intermicellar dispersion/aggregation in response to temperature cycles through an outer polymer shell lower critical solution temperature (LCST for PIPAAm=32.5 degrees C), observed by DLS (dynamic light scattering) and transmittance measurements. Upon heating above the LCST, PIPAAm-PBMA micelles exhibited an abrupt increase in micropolarity and an abrupt decrease in microrigidity sensed by pyrene and 1, 3-bis(1-pyrenyl)propane (PC(3)P), respectively. In contrast, PIPAAm-PSt micelles maintained constant values with lower micropolarity and higher microrigidity than those of PIPAAm-PBMA micelles over the temperature range 20 to 40 degrees C. From these results, structural deformations produced by outer shell polymer structural change with temperature cycles through the LCST are proposed for the PBMA core possessing a lower T(g) (ca. 20 degrees C) than the outer shell PIPAAm LCST. The PSt core with a much higher T(g) (ca. 100 degrees C) than the outer shell LCST retained its structure, regardless of outer shell changes. PIPAAm-PBMA micelles released ADR only when heated above the LCST, while PIPAAm-PSt micelles did not. Cell cultures treated with PIPAAm-PBMA micelles loaded with ADR showed high in vitro cytotoxicity when heated above the LCST, while PIPAAm-PSt micelles loaded with ADR expressed very low in vitro cytotoxicity irrespective of temperature change through the LCST. The nature of hydrophobic segments comprising the micelle inner core offers an important control point for thermo-responsive drug release and the drug activity of the thermo-responsive polymeric micelle.
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Affiliation(s)
- J E Chung
- Institute of Biomedical Engineering, Tokyo Women's Medical University, Kawada-cho 8-1, Shinjuku-ku, Tokyo, Japan
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Chung J, Yokoyama M, Suzuki K, Aoyagi T, Sakurai Y, Okano T. Reversibly thermo-responsive alkyl-terminated poly(N-isopropylacrylamide) core-shell micellar structures. Colloids Surf B Biointerfaces 1997. [DOI: 10.1016/s0927-7765(97)00015-5] [Citation(s) in RCA: 144] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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12
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Ferraretto A, Sonnino S, Soria MR, Masserini M. Characterization of biotinylated liposomes sensitive to temperature and pH: new tools for anti-cancer drug delivery. Chem Phys Lipids 1996; 82:133-9. [PMID: 8828169 DOI: 10.1016/0009-3084(96)02569-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We describe a liposome formulation characterized by sensitivity to concurrent and small temperature and pH changes. Liposome permeability was assessed by monitoring the release of entrapped carboxyfluorescein (CF), using a fluorescence dequenching technique. The thermotropic behavior of the liposomes was investigated by differential scanning calorimetry. After 2 h at 37 degrees C in fetal calf serum, liposomes composed of a mixture of dipalmitoyl phosphatidylcholine/cholesterol/GM1 ganglioside/biotinoyl-dipalmitoyl phosphatidylethanolamine (100:20:6:0.25 molar ratio) released 8% CF at pH 7.4 and 12% CF at pH 6.7. At 41 degrees C the leakage was 72% at pH 7.4 and almost complete (99%) at pH 6.7. The pH and temperature sensitivity, with maximal release when the two circumstances occurred simultaneously, was confirmed by entrapping calcein or [14C]glucose. The reasons for the bilayer sensitivity and the conditions for in vivo drug delivery are discussed.
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Affiliation(s)
- A Ferraretto
- Department of Medical Chemistry and Biochemistry, University of Milano, Italy
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Affiliation(s)
- A J Flach
- Department of Ophthalmology, University of California, San Francisco Medical Center, USA
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Peyman GA, Moshfeghi DM, Moshfeghi AA, Khoobehi B. Fluorescent Vesicle Angiography With Sodium Fluorescein and Indocyanine Green. Ophthalmic Surg Lasers Imaging Retina 1996. [DOI: 10.3928/1542-8877-19960401-07] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
Liposomes (phospholipid-based vesicles) have been investigated since 1970 as a system for the delivery or targeting of drugs to specific sites in the body. Because of their structural versatility in terms of size, composition, surface charge, bilayer fluidity and ability to incorporate almost any drug regardless of solubility, or to carry on their surface cell-specific ligands, liposomes have the potential to be tailored in a variety of ways to ensure the production of formulations that are optimal for clinical use. This includes controlled retention of entrapped drugs in the presence of biological fluids, controlled vesicle residence in the blood circulation or other compartments in the body, and enhanced vesicle uptake by target cells. Accumulated in vivo evidence, particularly in areas such as cancer chemotherapy, antimicrobial therapy, vaccines, diagnostic imaging and the treatment of ophthalmic disorders has indicated clearly that some liposome-entrapped drugs and vaccines exhibit superior pharmacological properties to those observed with conventional formulations. Such work has encouraged the application of liposomes in the treatment of diseases in humans. A large number of trials in patients with cancer or infections suggest that certain liposomal drug formulations are likely to prove clinically useful.
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Affiliation(s)
- G Gregoriadis
- Centre for Drug Delivery Research, School of Pharmacy, University of London, England
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18
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Abstract
Topical administration of drugs is the treatment of choice for diseases of the anterior segment. Drug levels attained by this means are usually of short duration, however, necessitating frequent therapy or continuous perfusion if prolonged drug levels are required. A drug-delivery device (collagen shield or contact lens) or subconjunctival injections can be used to augment topical therapy if frequent treatment is not possible. Subconjunctival injections are recommended for drugs that have low solubility and, hence, low corneal penetration. Retrobulbar injections are seldom indicated, except for regional anesthesia. Systemic administration is useful for anti-inflammatory therapy but it may be difficult to establish therapeutic levels of antibiotic agents in the eye because of the blood-ocular barrier. In severe cases, intraocular injection may be required.
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Affiliation(s)
- T R Miller
- Department of Small Animal Clinical Sciences, University of Florida College of Veterinary Medicine, Gainesville
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VanderMeulen DL, Misra P, Michael J, Spears KG, Khoka M. Laser mediated release of dye from liposomes. Photochem Photobiol 1992; 56:325-32. [PMID: 1438567 DOI: 10.1111/j.1751-1097.1992.tb02167.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Liposomes made from phospholipids and containing sulforhodamine dye (1-50 mM) have been irradiated with nanosecond and picosecond laser pulses. Individual liposomes were locally heated by laser absorption of dye dimers during a single laser pulse, and heating was sufficient to release the liposome contents. The extent of dye release produced by a single laser pulse was shown to be quantitatively dependent on several interdependent variables, including dye concentration, liposome size, laser excitation parameters and initial temperature of the dye-liposome system. Fluorescence lifetime data having three components have been obtained and analyzed in terms of three dye environments. Quantitative estimates support a photo-induced thermal mechanism for liposome lysis and release of its contents. These results may be useful for laser induced delivery of therapeutic agents or other applications of lasers in biological systems.
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20
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Díaz-Llopis M, Martos MJ, España E, Cervera M, Vila AO, Navea A, Molina FJ, Romero FJ. Liposomally-entrapped ganciclovir for the treatment of cytomegalovirus retinitis in AIDS patients. Eperimental toxicity and pharmacokinetics, and clinical trial. Doc Ophthalmol 1992; 82:297-305. [PMID: 1339115 DOI: 10.1007/bf00161017] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Treatment of retinitis by cytomegalovirus (CMV) in AIDS patients requires frequent repetitive injections of intravitreal ganciclovir (GCV). This study was undertaken to establish experimentally whether the intravitreal application of liposomally-entrapped GCV could prolong intraocular therapeutic levels when compared with the intravitreal injection of free GCV, and the clinical effectiveness of this approach in AIDS patients. Intraocular concentration of GCV was determined by means of an ELISA test in rabbit vitreous 2, 3, 7, and 14 days after a single intravitreal injection of either different doses of the free drug (0.2-20 mg) or 1 mg of liposomally-entrapped GCV. After 72 h, only the vitreous of rabbits injected with doses of free GCV greater than or equal to 5 mg showed therapeutic levels of the drug; no GCV was detected after 72 h with any of the doses applied. Moreover, the microscopic study revealed GCV-induced damage in retinal structures in the animals injected with a free GCV dose greater than or equal to 15 mg. Intravitreal injection to rabbits of 1 mg of liposomally-encapsulated GCV showed no retinal toxicity at any of the time points studied, and therapeutic levels were detected up to 14 days after injection (4.67 +/- 0.39 microgram/ml). Five AIDS patients suffering CMV retinitis were injected with 0.5 mg of liposomally-entrapped GCV (2 mg of lecithin). Complete remission of the CMV retinitis was observed already at the third injection of 0.5 mg GCV (one per week) and relapse did not occur during the 2-4 month follow-up of the patients. In view of the results presented, it can be concluded that intravitreal injection of liposomally-encapsulated GCV increases the time period required for reinjections in the treatment of CMV retinitis.
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Affiliation(s)
- M Díaz-Llopis
- Department of Surgery, School of Medicine and Dentistry, University of Valencia, Spain
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Khoobehi B, Peyman GA, Niesman MR, Oncel M. Measurement of retinal blood velocity and flow rate in primates using a liposome-dye system. Ophthalmology 1989; 96:905-12. [PMID: 2740083 DOI: 10.1016/s0161-6420(89)32807-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
A recently developed liposome-dye method was used to make quantitative measurements of blood velocity and volumetric flow rates in the retina of the rhesus monkey. After systemic injection of a liposome-encapsulated fluorescent dye (calcein), the release of a bolus of the dye in the retina was triggered by an ophthalmic argon laser. Initially, calcein was entrapped at a high concentration and the fluorescence of the dye in the lipid vesicle was quenched. After laser exposure, the liposomes released a bolus of dye at the laser exposure site in a specific vessel of the retina. The released dye formed a well-defined, fluorescent wavefront in the exposed artery or vein. By measuring the distance the dye traveled in the vein over a set time interval, it was possible to measure blood velocity in retinal vessels of various diameters, and to calculate volumetric flow rates in those vessels.
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Affiliation(s)
- B Khoobehi
- Louisiana State University Medical Center School of Medicine, New Orleans 70112
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