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Al-Kulabi A, Gooden L, Uchegbu IF. Nanoparticulate Mycophenolic Acid Eye Drops - Analytical Validation of a High Performance Liquid Chromatography Assay and Stability Studies. Pharm Nanotechnol 2021; 9:101-110. [PMID: 33430741 DOI: 10.2174/2211738509666210111161110] [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: 07/27/2020] [Revised: 11/09/2020] [Accepted: 11/25/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Mycophenolic acid (MPA), an immunosuppressive agent, is used orally to reduce corneal graft rejection. However, its oral use is associated with gastrointestinal side effects. OBJECTIVES This study aims to prepare: MPA nanoparticle eye drops and a validated analytical method. METHODS Aqueous MPA eye drops were prepared by nanoencapsulation of MPA using nanomerics MET (N-palamitoyl-N-monomethyl-N,N-dimethyl-N,N,N-trimethyl-6-O-glycolchitosan) at a MET and MPA ratio of 7.5: 1 g g-1 in the presence of glycerol (2.75% w/w). A validated MPA formulation drug substance assay was then conducted. RESULTS MET-MPA formulations were prepared as well as a validated assay. Assay validation parameters for the analysis of MPA in the formulation were satisfactory [Plate count = 16458, capacity Factor = 2.4, Tailing Factor = 1.02, linearity = 0.999 (0.016-0.5 mg mL-1), limit of detection = 0.056 mg mL-1, limit of quantification = 0.17 mg mL-1, accuracy = 98%, intraday and interday relative standard deviation = 0.45% and 4% respectively]. The candidate formulation (z-average mean = 66 ± 0.4 nm, polydispersity index = 0.12 ± 0.012, drug content = 1.14 ± 0.003 mg mL-1, zeta potential = +8.5 ± 1.4 mV, pH = 7.4 ± 0.02, osmolarity = 309 ± 1.5 mOSm L-1, viscosity = 1.04 ± 0.001 mPa.s) was then found to be stable for 14 days with respect to drug content at refrigeration, room and accelerated (40ºC) temperature. All other formulation parameters were within the ocular comfort range. CONCLUSION A validated assay (ICH and US FDA guidelines) for new MPA nanoparticle eye drops has been developed.
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Affiliation(s)
- Ali Al-Kulabi
- UCL School of Pharmacy, 29 - 39 Brunswick Square, London WC1N 1AX, United Kingdom
| | - Louis Gooden
- UCL School of Pharmacy, 29 - 39 Brunswick Square, London WC1N 1AX, United Kingdom
| | - Ijeoma F Uchegbu
- UCL School of Pharmacy, 29 - 39 Brunswick Square, London WC1N 1AX, United Kingdom
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Iqbal A, Zaman M, Wahab Amjad M, Adnan S, Abdul Ghafoor Raja M, Haider Rizvi SF, Mustafa MW, Farooq U, Abbas G, Shah S. Solid Lipid Nanoparticles of Mycophenolate Mofetil: An Attempt to Control the Release of an Immunosuppressant. Int J Nanomedicine 2020; 15:5603-5612. [PMID: 32848390 PMCID: PMC7428318 DOI: 10.2147/ijn.s255636] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 06/29/2020] [Indexed: 12/03/2022] Open
Abstract
Introduction Organ transplantation is a critically important procedure, which requires immune modulation by using immunosuppressants. Development of nanoparticles is an emerging and beneficial engineering process to increase the dissolution rate of poorly soluble immunosuppressants as well as to provide controlled release for better therapeutic outcomes. Method Currently, the nanoprecipitation method was employed to fabricate β-cyclodextrin (βCD) facilitated mycophenolate mofetil (MMF)-loaded solid lipid nanoparticles (SLNPs). The prime objectives of the study included, improvement of the dissolution profile of poorly aqueous soluble drug and controlled release from the SLNs to provide steady state drug concentration. Drug release from the prepared SLNs was assessed in two different media, ie, acidic buffer at pH 1.2 and phosphate buffer at pH 7.2 using USP dissolution apparatus for 12 h, followed by the evaluation of drug release mechanism and pattern by applying kinetic models. Results Justifiably, in acidic medium, the release was found to be 12% more (68%) in comparison to that in basic medium (56%). However, in both dissolution media, drug release was independent of initial concentration (R2>0.95) with non-Fickian type of diffusion mechanism. The outcomes of the study have exhibited that prepared formulations were in nanosized range (80–170 nm) with a net charge of ±23 charge on their surface. They possessed fairly uniform surface with acceptable polydispersity index (0.23±0.09). Scanning electron microscopy (SEM) analysis illustrated that the nanoparticles had uniform particle size and shape. Discussion The findings show potential applications of the nanoparticles and the method for the development of SLNPs in controlled release of MMF for better therapeutic outcomes. Conclusively, the prepared SLNPs were well designed in nanosized ranges and justifying the once daily controlled release formulation dose of MMF to enhance patient compliance.
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Affiliation(s)
- Asma Iqbal
- Faculty of Pharmacy, The University of Lahore, Lahore, Pakistan
| | - Muhammad Zaman
- Faculty of Pharmacy, The University of Lahore, Lahore, Pakistan.,Faculty of Pharmacy, University of Central Punjab, Lahore, Pakistan
| | | | - Sharjeel Adnan
- Faculty of Pharmacy, The University of Lahore, Lahore, Pakistan
| | | | | | | | - Umer Farooq
- Faculty of Pharmacy, University of Central Punjab, Lahore, Pakistan
| | - Ghulam Abbas
- Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Shahid Shah
- Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad, Pakistan
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Lapp T, Maier P, Birnbaum F, Schlunck G, Reinhard T. [Immunosuppressives to prevent rejection reactions after allogeneic corneal transplantation]. Ophthalmologe 2015; 111:270-82. [PMID: 24633461 DOI: 10.1007/s00347-013-3016-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In order to prevent rejection of an allogeneic corneal transplant after perforating (high risk) keratoplasty, active agents from different classes of pharmacological substances are used, as with solid organ transplantation. In addition to glucocorticoids, antiproliferative agents, small molecule inhibitors and antibodies, those belonging to the group of macrolides with their many derivatives represent an interesting class of substances in this context. As a supplement to cyclosporin A (CSA) the most successful macrolide in transplantation medicine, animal experiments are currently being carried out to test newer macrolide derivatives, such as sanglifehrin A (SFA). This overview describes the classes of drugs and modes of action of currently administered standard medications in the clinical routine and new developments are presented.
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Affiliation(s)
- T Lapp
- Klinik für Augenheilkunde, Universitätsklinikum Freiburg, Killianstr. 5, 79106, Freiburg im Breisgau, Deutschland,
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Ru Q, Fadda HM, Li C, Paul D, Khaw PT, Brocchini S, Zloh M. Molecular dynamic simulations of ocular tablet dissolution. J Chem Inf Model 2013; 53:3000-8. [PMID: 24073784 DOI: 10.1021/ci4002348] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Small tablets for implantation into the subconjunctival space in the eye are being developed to inhibit scarring after glaucoma filtration surgery (GFS). There is a need to evaluate drug dissolution at the molecular level to determine how the chemical structure of the active may correlate with dissolution in the nonsink conditions of the conjunctival space. We conducted molecular dynamics simulations to study the dissolution process of tablets derived from two drugs that can inhibit fibrosis after GFS, 5-fluorouracil (5-FU) and the matrix metalloprotease inhibitor (MMPi), ilomastat. The dissolution was simulated in the presence of simple point charge (SPC) water molecules, and the liquid turnover of the aqueous humor in the subconjunctival space was simulated by removal of the dissolved drug molecules at regular intervals and replacement by new water molecules. At the end of the simulation, the total molecular solvent accessible surface area of 5-FU tablets increased by 60 times more than that of ilomastat as a result of tablet swelling and release of molecules into solution. The tablet dissolution pattern shown in our molecular dynamic simulations tends to correlate with experimental release profiles. This work indicates that a series of molecular dynamic simulations can be used to predict the influence of the molecular properties of a drug on its dissolution profile and could be useful during preformulation where sufficient amounts of the drug are not always available to perform dissolution studies.
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Affiliation(s)
- Qian Ru
- UCL School of Pharmacy , 29/39 Brunswick Square, London WC1N 1AX, United Kingdom
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Cholkar K, Patel SP, Vadlapudi AD, Mitra AK. Novel strategies for anterior segment ocular drug delivery. J Ocul Pharmacol Ther 2012; 29:106-23. [PMID: 23215539 DOI: 10.1089/jop.2012.0200] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Research advancements in pharmaceutical sciences have led to the development of new strategies in drug delivery to anterior segment. Designing a new delivery system that can efficiently target the diseased anterior ocular tissue, generate high drug levels, and maintain prolonged and effective concentrations with no or minimal side effects is the major focus of current research. Drug delivery by traditional method of administration via topical dosing is impeded by ocular static and dynamic barriers. Various products have been introduced into the market that prolong drug retention in the precorneal pocket and to improve bioavailability. However, there is a need of a delivery system that can provide controlled release to treat chronic ocular diseases with a reduced dosing frequency without causing any visual disturbances. This review provides an overview of anterior ocular barriers along with strategies to overcome these ocular barriers and deliver therapeutic agents to the affected anterior ocular tissue with a special emphasis on nanotechnology-based drug delivery approaches.
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Affiliation(s)
- Kishore Cholkar
- Division of Pharmaceutical Sciences, University of Missouri-Kansas City, Kansas City, MO 64108-2718, USA
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Xin M, Wang T, Shi W, Wu X. Experimental Efficacy of Mycophenolate Mofetil Implant on High-Risk Corneal Allograft Rejection and Its Biocompatibility in the Anterior Chamber of Rabbits. J Ocul Pharmacol Ther 2012; 28:609-17. [DOI: 10.1089/jop.2012.0065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Meng Xin
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, P.R. China
| | - Ting Wang
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, P.R. China
| | - Weiyun Shi
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, P.R. China
| | - Xianggen Wu
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, P.R. China
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Wu XG, Xin M, Yang LN, Shi WY. The Biological Characteristics and Pharmacodynamics of a Mycophenolate Mofetil Nanosuspension Ophthalmic Delivery System in Rabbits. J Pharm Sci 2011; 100:1350-61. [DOI: 10.1002/jps.22356] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 06/17/2010] [Accepted: 08/31/2010] [Indexed: 11/11/2022]
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Zhang L, Zhang J, Wang L, Xia H. Ocular pharmacokinetics and availability of topically applied baicalein in rabbits. Curr Eye Res 2009; 34:257-63. [PMID: 19373573 DOI: 10.1080/02713680902725962] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE To evaluate the ocular pharmacokinetics and availability of baicalein following topical application. METHODS Hydroxypropyl beta-cyclodextrin (HP-beta -CD) was used to formulate an aqueous eye drop to improve aqueous solubility of baicalein. A single dose of either baicalein suspension (1%) (Bai-SP) or baicalein (1%)/HP-beta-CD (10%) solution (Bai-CD) was topically applied to rabbits. Aqueous humor and cornea were collected after 5, 10, 20, 30, 45, 60, 90, and 120 min. Baicalein concentrations were determined by high-performance liquid chromatography (HPLC) after extraction. RESULTS After topically applying Bai-CD, the baicalein concentrations in aqueous humor were significantly increased at 20-120 min except at 90 min compared with those of Bai-SP (p < 0.05). The highest levels of baicalein in aqueous humor (Cmax, 4.11 +/- 0.75 microg/ml) were obtained after 30 min application of Bai-CD, 3.6 times greater than that corresponding to the Bai-SP at 20 min. The Bai-CD produced an over 2.1-fold bioavailability (AUC(0-120), area under the concentration time curve between 0 and 120 min) increase in aqueous humor compared to the Bai-SP. Peak baicalein concentration in cornea (56.53 +/- 17.02 microg/g) was achieved within 5 min after topical application of Bai-CD and 4.5 times higher than that of Bai-SP at the same timepoint. The baicalein levels in corneas obtained after application of Bai-CD were all much higher than those obtained by Bai-SP (p < 0.01), whereas the drug levels became undetectable 30 min after topical application of Bai-SP. CONCLUSION Bai-CD formulation is superior to Bai-SP for increasing ocular bioavailability.
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Affiliation(s)
- Li Zhang
- Henan Eye Institute, No. 7 Weiwu Road, Zhengzhou, Henan Province 450003, China.
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Zhang J, Wang L, Gao C, Zhang L, Xia H. Ocular Pharmacokinetics of Topically-Applied Ketoconazole Solution Containing Hydroxypropyl Beta-Cyclodextrin to Rabbits. J Ocul Pharmacol Ther 2008; 24:501-6. [DOI: 10.1089/jop.2008.0015] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Junjie Zhang
- Pharmaceutic and Pharmacology Department, Henan Eye Institute, Henan Key Laboratory of Keratopathy, Zhengzhou, China
| | - Liya Wang
- Pharmaceutic and Pharmacology Department, Henan Eye Institute, Henan Key Laboratory of Keratopathy, Zhengzhou, China
| | - Changfeng Gao
- Pharmaceutic and Pharmacology Department, Henan Eye Institute, Henan Key Laboratory of Keratopathy, Zhengzhou, China
| | - Li Zhang
- Pharmaceutic and Pharmacology Department, Henan Eye Institute, Henan Key Laboratory of Keratopathy, Zhengzhou, China
| | - Huiyun Xia
- Pharmaceutic and Pharmacology Department, Henan Eye Institute, Henan Key Laboratory of Keratopathy, Zhengzhou, China
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Buech G, Bertelmann E, Pleyer U, Siebenbrodt I, Borchert HH. Formulation of Sirolimus Eye Drops and Corneal Permeation Studies. J Ocul Pharmacol Ther 2007; 23:292-303. [PMID: 17593014 DOI: 10.1089/jop.2006.130] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The aim of this study was the development of eye drops with 1 mg/mL sirolimus and the evaluation of the drug's ability to permeate the freshly isolated pig cornea. Cyclodextrin solutions, liposomes, hydrotrope mixtures, poloxamer gels, and a microemulsion were tested for their suitability to dissolve the extremely hydrophobic drug sirolimus (solubility in water 2.6 microg/mL). The drug content in the formulations was determined by high-performance liquid chromatography, whereas this method is not sensitive enough for the quantification of therapeutic concentrations (7-12 ng/mL). Thus, the acceptor samples of the permeation tests were examined by microparticle enzyme immunoassay. A microemulsion is a suitable vehicle to prepare eye drops with sufficient sirolimus concentrations of 1 mg/mL in a formulation with acceptable tolerance and satisfactory stability over 12 months. However, the drug cannot permeate the intact cornea. After removal of the corneal epithelium, drug concentrations in the acceptor sample reach the lower limit of therapeutical levels. Conclusively, the present sirolimus eye drops might be promising therapeutic tools for the immunomodulatory treatment of ocular surface disorders, such as keratoconjunctivitis sicca, vernal conjunctivitis, or atopical blepharitis. They are not suitable to achieve therapeutic concentrations in the aqueous humour of patients with intact cornea.
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Affiliation(s)
- Guido Buech
- Institute of Pharmacy, Free University of Berlin, Berlin, Germany
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Abstract
Topical steroids are routinely used in the postoperative treatment following penetrating keratoplasty. Due to the known side effects such as steroid-response glaucoma, cataract, and surface disorders, a broader armamentarium of topical immunomodulating drugs with comparable efficacy, better tolerance and less side effects is desirable. Cyclosporine A and FK506 eye drops are a promising alternative. A new approach involves subconjunctival drug delivering implants and locally applied antiangiogenic substances, which still have to be tested in clinical studies.
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Affiliation(s)
- F Birnbaum
- Universitätsaugenklinik Freiburg, 79106, Freiburg.
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Loftsson T, Stefánsson E. Cyclodextrins in ocular drug delivery: theoretical basis with dexamethasone as a sample drug. J Drug Deliv Sci Technol 2007. [DOI: 10.1016/s1773-2247(07)50001-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Choudhary A, Harding SP, Bucknall RC, Pearce IA. Mycophenolate mofetil as an immunosuppressive agent in refractory inflammatory eye disease. J Ocul Pharmacol Ther 2006; 22:168-75. [PMID: 16808677 DOI: 10.1089/jop.2006.22.168] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE The aim of this study was to assess the role of mycophenolate mofetil (MMF) in refractory inflammatory eye disease. METHODS Retrospective, noncomparative, interventional case series of all patients commenced on MMF between 1999 and 2005 for refractory inflammatory eye disease at St Paul's Eye Unit (Liverpool, UK). Main outcome measures noted were control of inflammation, steroid-sparing effect, and adverse effects of MMF therapy. RESULTS Ten (10) patients (2 with sarcoid, 2 with intermediate uveitis, 1 with Vogt-Koyanagi Harada (VKH) syndrome, 1 with ankylosing spondylitis, 1 with juvenile chronic arthritis (JCA), and 3 with scleritis) who were unresponsive or intolerant to previous therapy and/or as a steroid-sparing agent, received 2-3 g of MMF per day for a mean period of 40.5 months (range, 3-67). Nine (9) patients had a favorable response, with diarrhea and insomnia being the main side-effects. MMF had to be withdrawn in 1 patient because of side-effects and in another because of active arthropathy (with stable uveitis). Average number of relapses was reduced from 3.1 per patient per year to 0.8 per patient per year (P < 0.005). A steroid-sparing effect was achieved in all patients. Visual acuity improved in 8 patients. CONCLUSIONS MMF appears to be a safe and effective second- or third-line adjunct/alternative immunosuppressant in these difficult cases and works well in combination with cyclosporin A, tacrolimus, and antitumor necrosis factor (TNF) agents. It has potential as a firstor second-line agent and can be considered at a dose of 3 g/day in refractory cases.
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Affiliation(s)
- Anshoo Choudhary
- St. Paul's Eye Unit, Royal Liverpool and Broadgreen University Hospital, Liverpool, UK.
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Bertelmann E, Pleyer U. Immunomodulatory Therapy in Ophthalmology – Is There a Place for Topical Application? Ophthalmologica 2004; 218:359-67. [PMID: 15564752 DOI: 10.1159/000080937] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2003] [Accepted: 01/23/2004] [Indexed: 11/19/2022]
Abstract
Topical corticosteroids, although effective in the treatment of ocular immune-mediated diseases, are well known for their ocular side-effects. Not surprisingly, a variety of alternative immunomodulatory agents have been tested for topical use including cyclosporin A (CsA), mycophenolate mofetil (MMF), tacrolimus (FK506), rapamycin (sirolimus) and leflunomide. Local application bears the possibility to avoid the severe side-effects of systemic therapy. The effect of topical therapy is naturally restricted to local immune response mechanisms, such as antigen presentation by Langerhans and dendritic cells. Moreover, many immunomodulatory agents (e.g. CsA) are lipophilic and thus have low water solubility and penetrate insufficiently intra-ocularly, often being stored in the lipophilic corneal epithelial barrier. Therefore, the therapeutical success is limited for intra-ocular immune-mediated diseases like anterior uveitis. However, a multitude of strategies have been introduced to circumvent these problems including complexing substances such as cyclodextrins (CDs) and liposomes. In the prevention and treatment of transplant rejection after keratoplasty, many attempts to introduce topical immunomodulatory therapy have failed; on the other hand, further therapeutic options not primarily expected are being evaluated today such as treatment of severe keratoconjunctivitis sicca. In our own studies, we investigated the pharmacokinetics of topical treatment with different agents including MMF and evaluated the efficacy of topical treatment in animal models for uveitis and keratoplasty. Taken together, topical immunomodulatory therapy will not replace systemic therapy but further treatment options can be expected.
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Affiliation(s)
- Eckart Bertelmann
- Augenklinik Charité - Universitätsmedizin Berlin, Campus Virchow Klinikum, Berlin, Deutschland.
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Abstract
The immune privileged nature of the cornea contributes to the favourable outcome in corneal grafts. However, preventive measures are necessary to reduce allograft rejection particular in "high-risk" cases. Although corticosteroids are still a major component of our immunopharmacological armentarium, they might be supplemented by other more specific immunomodulating agents. The spectrum includes agents such as azathioprin, methotrexate or more specific calcineurin inhibitors affecting T-cells (cyclosporin A, FK506) and highly selective monoclonal antibodies directed against T-cell subpopulations and other targets. In order to better evaluate the risks and benefit of these agents, the properties of established and forthcoming agents are presented. In addition, this review attempts to address some new concepts of tolerance induction following penetrating keratoplasty.
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Affiliation(s)
- U Pleyer
- Augenklinik, Charité, Universitätsmedizin Berlin, Campus Virchow Klinikum, Berlin.
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