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Amrutkar CS, Patil SB. Nanocarriers for ocular drug delivery: Recent advances and future opportunities. Indian J Ophthalmol 2023; 71:2355-2366. [PMID: 37322644 PMCID: PMC10418032 DOI: 10.4103/ijo.ijo_1893_22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 12/27/2022] [Accepted: 04/06/2023] [Indexed: 06/17/2023] Open
Abstract
Topical route of administration is very important and the most commonly used method of drug delivery for treatment of ocular diseases. However, due to unique anatomical and physiological barriers of eye, it is difficult to achieve the therapeutic concentration in the targeted tissue within the eye. To overcome the effect of these barriers in absorption and to provide targeted and sustained drug delivery, various advances have been made in developing safe and efficient drug delivery systems. Various formulation strategies for ocular drug delivery are used, like basic formulation techniques for improving availability of drugs, viscosity enhancers, and use of mucoadhesives for drug retention and penetration enhancers to promote drug transport to the eye. In this review, we present a summary of the current literature to understand the anatomical and physiological limitations in achieving adequate ocular bioavailability and targeted drug delivery of topically applied drugs and use of new techniques in formulating dosage forms in overcoming these limitations. The recent and future advances in nanocarrier-mediated drug delivery may have the potential to provide patient-friendly and noninvasive techniques for the treatment of diseases related to the anterior and posterior segments of the eye.
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Affiliation(s)
- Chetan S Amrutkar
- Department of Pharmaceutics, SNJB’s Shriman Sureshdada Jain College of Pharmacy, Nashik, Maharashtra, India
| | - Sanjay B Patil
- Department of Pharmaceutics, SNJB’s Shriman Sureshdada Jain College of Pharmacy, Nashik, Maharashtra, India
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Li L, Jia F, Wang Y, Liu J, Tian Y, Sun X, Lei Y, Ji J. Trans-corneal drug delivery strategies in the treatment of ocular diseases. Adv Drug Deliv Rev 2023; 198:114868. [PMID: 37182700 DOI: 10.1016/j.addr.2023.114868] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 04/20/2023] [Accepted: 05/07/2023] [Indexed: 05/16/2023]
Abstract
The cornea is a remarkable tissue that possesses specialized structures designed to safeguard the eye against foreign objects. However, its unique properties also make it challenging to deliver drugs in a non-invasive manner. This review highlights recent advancements in achieving highly efficient drug transport across the cornea, focusing on nanomaterials. We have classified these strategies into three main categories based on their mechanisms and have analyzed their success and limitations in a systematic manner. The purpose of this review is to examine potential general principles that could improve drug penetration through the cornea and other natural barriers in the eye. We hope it will inspire the development of more effective drug delivery systems that can better treat ocular diseases.
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Affiliation(s)
- Liping Li
- Shanghai Key Laboratory of Visual Impairment and Restoration, Key Laboratory of Myopia of Ministry of Health, Eye and ENT Hospital of Fudan University, Shanghai 200031, PR China
| | - Fan Jia
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization of Ministry of Education, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027 Zhejiang Province, PR China
| | - Youxiang Wang
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization of Ministry of Education, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027 Zhejiang Province, PR China
| | - Jiamin Liu
- Shanghai Key Laboratory of Visual Impairment and Restoration, Key Laboratory of Myopia of Ministry of Health, Eye and ENT Hospital of Fudan University, Shanghai 200031, PR China
| | - Yi Tian
- Shanghai Key Laboratory of Visual Impairment and Restoration, Key Laboratory of Myopia of Ministry of Health, Eye and ENT Hospital of Fudan University, Shanghai 200031, PR China
| | - Xinghuai Sun
- Shanghai Key Laboratory of Visual Impairment and Restoration, Key Laboratory of Myopia of Ministry of Health, Eye and ENT Hospital of Fudan University, Shanghai 200031, PR China.
| | - Yuan Lei
- Shanghai Key Laboratory of Visual Impairment and Restoration, Key Laboratory of Myopia of Ministry of Health, Eye and ENT Hospital of Fudan University, Shanghai 200031, PR China.
| | - Jian Ji
- MOE Key Laboratory of Macromolecule Synthesis and Functionalization of Ministry of Education, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027 Zhejiang Province, PR China.
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Akhter MH, Ahmad I, Alshahrani MY, Al-Harbi AI, Khalilullah H, Afzal O, Altamimi ASA, Najib Ullah SNM, Ojha A, Karim S. Drug Delivery Challenges and Current Progress in Nanocarrier-Based Ocular Therapeutic System. Gels 2022; 8:82. [PMID: 35200463 PMCID: PMC8871777 DOI: 10.3390/gels8020082] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 01/16/2022] [Accepted: 01/18/2022] [Indexed: 02/01/2023] Open
Abstract
Drug instillation via a topical route is preferred since it is desirable and convenient due to the noninvasive and easy drug access to different segments of the eye for the treatment of ocular ailments. The low dose, rapid onset of action, low or no toxicity to the local tissues, and constrained systemic outreach are more prevalent in this route. The majority of ophthalmic preparations in the market are available as conventional eye drops, which rendered <5% of a drug instilled in the eye. The poor drug availability in ocular tissue may be attributed to the physiological barriers associated with the cornea, conjunctiva, lachrymal drainage, tear turnover, blood-retinal barrier, enzymatic drug degradation, and reflex action, thus impeding deeper drug penetration in the ocular cavity, including the posterior segment. The static barriers in the eye are composed of the sclera, cornea, retina, and blood-retinal barrier, whereas the dynamic barriers, referred to as the conjunctival and choroidal blood flow, tear dilution, and lymphatic clearance, critically impact the bioavailability of drugs. To circumvent such barriers, the rational design of the ocular therapeutic system indeed required enriching the drug holding time and the deeper permeation of the drug, which overall improve the bioavailability of the drug in the ocular tissue. This review provides a brief insight into the structural components of the eye as well as the therapeutic challenges and current developments in the arena of the ocular therapeutic system, based on novel drug delivery systems such as nanomicelles, nanoparticles (NPs), nanosuspensions, liposomes, in situ gel, dendrimers, contact lenses, implants, and microneedles. These nanotechnology platforms generously evolved to overwhelm the troubles associated with the physiological barriers in the ocular route. The controlled-drug-formulation-based strategic approach has considerable potential to enrich drug concentration in a specific area of the eye.
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Affiliation(s)
- Md Habban Akhter
- School of Pharmaceutical and Population Health Informatics (SoPPHI), DIT University, Dehradun 248009, India
| | - Irfan Ahmad
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha 62521, Saudi Arabia; (I.A.); (M.Y.A.)
| | - Mohammad Y. Alshahrani
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha 62521, Saudi Arabia; (I.A.); (M.Y.A.)
| | - Alhanouf I. Al-Harbi
- Department of Medical Laboratory, College of Applied Medical Sciences, Taibah University, Yanbu 46477, Saudi Arabia;
| | - Habibullah Khalilullah
- Department of Pharmaceutical Chemistry and Pharmacognosy, Unaizah College of Pharmacy, Qassim University, Unaizah 51911, Saudi Arabia;
| | - Obaid Afzal
- Department of Pharmaceutical Chemistry, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia; (O.A.); (A.S.A.A.)
| | - Abdulmalik S. A. Altamimi
- Department of Pharmaceutical Chemistry, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia; (O.A.); (A.S.A.A.)
| | | | - Abhijeet Ojha
- Six Sigma Institute of Technology and Science, College of Pharmacy, Rudrapur 263153, India;
| | - Shahid Karim
- Department of Pharmacology, College of Medicine, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
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Topical Pharmacokinetics of Dexamethasone Suspensions in the Rabbit Eye: Bioavailability Comparison. Int J Pharm 2022; 615:121515. [DOI: 10.1016/j.ijpharm.2022.121515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 01/16/2022] [Accepted: 01/21/2022] [Indexed: 11/21/2022]
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Mazet R, Yaméogo JBG, Wouessidjewe D, Choisnard L, Gèze A. Recent Advances in the Design of Topical Ophthalmic Delivery Systems in the Treatment of Ocular Surface Inflammation and Their Biopharmaceutical Evaluation. Pharmaceutics 2020; 12:pharmaceutics12060570. [PMID: 32575411 PMCID: PMC7356360 DOI: 10.3390/pharmaceutics12060570] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/06/2020] [Accepted: 06/09/2020] [Indexed: 12/17/2022] Open
Abstract
Ocular inflammation is one of the most common symptom of eye disorders and diseases. The therapeutic management of this inflammation must be rapid and effective in order to avoid deleterious effects for the eye and the vision. Steroidal (SAID) and non-steroidal (NSAID) anti-inflammatory drugs and immunosuppressive agents have been shown to be effective in treating inflammation of the ocular surface of the eye by topical administration. However, it is well established that the anatomical and physiological ocular barriers are limiting factors for drug penetration. In addition, such drugs are generally characterized by a very low aqueous solubility, resulting in low bioavailability as only 1% to 5% of the applied drug permeates the cornea. The present review gives an updated insight on the conventional formulations used in the treatment of ocular inflammation, i.e., ointments, eye drops, solutions, suspensions, gels, and emulsions, based on the commercial products available on the US, European, and French markets. Additionally, sophisticated formulations and innovative ocular drug delivery systems will be discussed. Promising results are presented with micro- and nanoparticulated systems, or combined strategies with polymers and colloidal systems, which offer a synergy in bioavailability and sustained release. Finally, different tools allowing the physical characterization of all these delivery systems, as well as in vitro, ex vivo, and in vivo evaluations, will be considered with regards to the safety, the tolerance, and the efficiency of the drug products.
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Affiliation(s)
- Roseline Mazet
- DPM, UMR CNRS 5063, ICMG FR 2607, Faculty of Pharmacy, University of Grenoble Alpes, 38400 St Martin d’Hères, France; (R.M.); (D.W.); (L.C.)
- Grenoble University Hospital, 38043 Grenoble, France
| | | | - Denis Wouessidjewe
- DPM, UMR CNRS 5063, ICMG FR 2607, Faculty of Pharmacy, University of Grenoble Alpes, 38400 St Martin d’Hères, France; (R.M.); (D.W.); (L.C.)
| | - Luc Choisnard
- DPM, UMR CNRS 5063, ICMG FR 2607, Faculty of Pharmacy, University of Grenoble Alpes, 38400 St Martin d’Hères, France; (R.M.); (D.W.); (L.C.)
| | - Annabelle Gèze
- DPM, UMR CNRS 5063, ICMG FR 2607, Faculty of Pharmacy, University of Grenoble Alpes, 38400 St Martin d’Hères, France; (R.M.); (D.W.); (L.C.)
- Correspondence: ; Tel.: +33-476-63-53-01
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Souto EB, Dias-Ferreira J, López-Machado A, Ettcheto M, Cano A, Camins Espuny A, Espina M, Garcia ML, Sánchez-López E. Advanced Formulation Approaches for Ocular Drug Delivery: State-Of-The-Art and Recent Patents. Pharmaceutics 2019; 11:pharmaceutics11090460. [PMID: 31500106 PMCID: PMC6781321 DOI: 10.3390/pharmaceutics11090460] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 08/23/2019] [Accepted: 08/26/2019] [Indexed: 12/17/2022] Open
Abstract
The eye presents extensive perspectives and challenges for drug delivery, mainly because of the extraordinary capacity, intrinsic to this path, for drugs to permeate into the main circulatory system and also for the restrictions of the ocular barriers. Depending on the target segment of the eye, anterior or posterior, the specifications are different. The ocular route experienced in the last decades a lot of progresses related with the development of new drugs, improved formulations, specific-designed delivery and even new routes to administer a drug. Concomitantly, new categories of materials were developed and adapted to encapsulate drugs. With such advances, a multiplicity of parameters became possible to be optimized as the increase in bioavailability and decreased toxic effects of medicines. Also, the formulations were capable to easily adhere to specific tissues, increase the duration of the therapeutic effect and even target the delivery of the treatment. The ascending of new delivery systems for ocular targeting is a current focus, mainly because of the capacity to extend the normal time during which the drug exerts its therapeutic effect and, so, supplying the patients with a product which gives them fewer side effects, fewer number of applications and even more effective outcomes to their pathologies, surpassing the traditionally-used eye drops. Depending on the systems, some are capable of increasing the duration of the drug action as gels, emulsions, prodrugs, liposomes, and ocular inserts with hydrophilic properties, improving the absorption by the cornea. In parallel, other devices use as a strategy the capacity to sustain the release of the carried drugs by means of erodible and non-erodible matrices. This review discusses the different types of advanced formulations used for ocular delivery of therapeutics presenting the most recent patents according to the clinical applications.
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Affiliation(s)
- Eliana B Souto
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, 3000-458 Coimbra, Portugal.
- CEB-Centre of Biological Engineering, University of Minho, Campus de Gualtar 4710-057 Braga, Portugal.
| | - João Dias-Ferreira
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, 3000-458 Coimbra, Portugal
| | - Ana López-Machado
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Miren Ettcheto
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), University of Barcelona, 08028 Barcelona, Spain
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
| | - Amanda Cano
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), University of Barcelona, 08028 Barcelona, Spain
| | - Antonio Camins Espuny
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), University of Barcelona, 08028 Barcelona, Spain
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
| | - Marta Espina
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
| | - Maria Luisa Garcia
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), University of Barcelona, 08028 Barcelona, Spain
| | - Elena Sánchez-López
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, 3000-458 Coimbra, Portugal.
- Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain.
- Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, 08028 Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), University of Barcelona, 08028 Barcelona, Spain.
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Gote V, Sikder S, Sicotte J, Pal D. Ocular Drug Delivery: Present Innovations and Future Challenges. J Pharmacol Exp Ther 2019; 370:602-624. [DOI: 10.1124/jpet.119.256933] [Citation(s) in RCA: 141] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 05/01/2019] [Indexed: 12/12/2022] Open
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Pharmaceutical challenges and perspectives in developing ophthalmic drug formulations. JOURNAL OF PHARMACEUTICAL INVESTIGATION 2018. [DOI: 10.1007/s40005-018-0404-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Barar J, Aghanejad A, Fathi M, Omidi Y. Advanced drug delivery and targeting technologies for the ocular diseases. BIOIMPACTS : BI 2016; 6:49-67. [PMID: 27340624 PMCID: PMC4916551 DOI: 10.15171/bi.2016.07] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 02/13/2016] [Accepted: 03/18/2016] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Ocular targeted therapy has enormously been advanced by implementation of new methods of drug delivery and targeting using implantable drug delivery systems (DDSs) or devices (DDDs), stimuli-responsive advanced biomaterials, multimodal nanomedicines, cell therapy modalities and medical bioMEMs. These technologies tackle several ocular diseases such as inflammation-based diseases (e.g., scleritis, keratitis, uveitis, iritis, conjunctivitis, chorioretinitis, choroiditis, retinitis, retinochoroiditis), ocular hypertension and neuropathy, age-related macular degeneration and mucopolysaccharidosis (MPS) due to accumulation of glycosaminoglycans (GAGs). Such therapies appear to provide ultimate treatments, even though much more effective, yet biocompatible, noninvasive therapies are needed to control some disabling ocular diseases/disorders. METHODS In the current study, we have reviewed and discussed recent advancements on ocular targeted therapies. RESULTS On the ground that the pharmacokinetic and pharmacodynamic analyses of ophthalmic drugs need special techniques, most of ocular DDSs/devices developments have been designed to localized therapy within the eye. Application of advanced DDSs such as Subconjunctival insert/implants (e.g., latanoprost implant, Gamunex-C), episcleral implant (e.g., LX201), cationic emulsions (e.g., Cationorm™, Vekacia™, Cyclokat™), intac/punctal plug DDSs (latanoprost punctal plug delivery system, L-PPDS), and intravitreal implants (I-vitaion™, NT-501, NT- 503, MicroPump, Thethadur, IB-20089 Verisome™, Cortiject, DE-102, Retisert™, Iluvein™ and Ozurdex™) have significantly improved the treatment of ocular diseases. However, most of these DDSs/devices are applied invasively and even need surgical procedures. Of these, use of de novo technologies such as advanced stimuli-responsive nanomaterials, multimodal nanosystems (NSs)/nanoconjugates (NCs), biomacromolecualr scaffolds, and bioengineered cell therapies need to be further advanced to get better compliance and higher clinical impacts. CONCLUSION Despite mankind successful battle on ocular diseases, our challenge will continue to battle the ocular disease that happen with aging. Yet, we need to understand the molecular aspects of eye diseases in a holistic way and develop ultimate treatment protocols preferably as non-invasive systems.
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Affiliation(s)
| | | | | | - Yadollah Omidi
- Research Centre for Pharmaceutical Nanotechnology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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Boddu SHS, Bonam SP, Jung R. Development and characterization of a ricinoleic acid poloxamer gel system for transdermal eyelid delivery. Drug Dev Ind Pharm 2014; 41:605-12. [DOI: 10.3109/03639045.2014.886696] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Patel A, Cholkar K, Agrahari V, Mitra AK. Ocular drug delivery systems: An overview. World J Pharmacol 2013; 2:47-64. [PMID: 25590022 PMCID: PMC4289909 DOI: 10.5497/wjp.v2.i2.47] [Citation(s) in RCA: 476] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/25/2012] [Revised: 03/21/2013] [Accepted: 04/04/2013] [Indexed: 02/06/2023] Open
Abstract
The major challenge faced by today’s pharmacologist and formulation scientist is ocular drug delivery. Topical eye drop is the most convenient and patient compliant route of drug administration, especially for the treatment of anterior segment diseases. Delivery of drugs to the targeted ocular tissues is restricted by various precorneal, dynamic and static ocular barriers. Also, therapeutic drug levels are not maintained for longer duration in target tissues. In the past two decades, ocular drug delivery research acceleratedly advanced towards developing a novel, safe and patient compliant formulation and drug delivery devices/techniques, which may surpass these barriers and maintain drug levels in tissues. Anterior segment drug delivery advances are witnessed by modulation of conventional topical solutions with permeation and viscosity enhancers. Also, it includes development of conventional topical formulations such as suspensions, emulsions and ointments. Various nanoformulations have also been introduced for anterior segment ocular drug delivery. On the other hand, for posterior ocular delivery, research has been immensely focused towards development of drug releasing devices and nanoformulations for treating chronic vitreo-retinal diseases. These novel devices and/or formulations may help to surpass ocular barriers and associated side effects with conventional topical drops. Also, these novel devices and/or formulations are easy to formulate, no/negligibly irritating, possess high precorneal residence time, sustain the drug release, and enhance ocular bioavailability of therapeutics. An update of current research advancement in ocular drug delivery necessitates and helps drug delivery scientists to modulate their think process and develop novel and safe drug delivery strategies. Current review intends to summarize the existing conventional formulations for ocular delivery and their advancements followed by current nanotechnology based formulation developments. Also, recent developments with other ocular drug delivery strategies employing in situ gels, implants, contact lens and microneedles have been discussed.
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Andrew R, Luecke G, Dozier S, Diven DG. A pilot study to investigate the efficacy of tobramycin-dexamethasone ointment in promoting wound healing. Dermatol Ther (Heidelb) 2012. [PMID: 23205334 PMCID: PMC3510414 DOI: 10.1007/s13555-012-0012-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION The standard postsurgical treatment of wounds after dermatologic procedures is currently limited. Topical corticosteroids have been used successfully in postoperative management of ophthalmologic surgeries that involve the skin of the eyelid. In particular, tobramycin 0.3%/dexamethasone 0.1% ophthalmic ointment is considered the "gold standard" of steroid-antibiotic fixed combinations and is marketed worldwide as an agent used to control postsurgical inflammation and prevent postsurgical infection. The purpose of this study is to evaluate both the efficacy and safety of tobramycin-dexamethasone ointment for the postsurgical management of Mohs or dermatologic surgery in comparison to white petrolatum. METHODS The authors employed a half-scar study in which patients who underwent skin cancer removal surgery were given tobramycin-dexamethasone ointment and white petrolatum to apply to each half of their wound for 2 weeks. The study was double blinded, and physicians and the patients independently evaluated the scars for cosmetic appearance at 2 and 6 weeks postoperatively. The evaluation criteria included judging which side of the wound looked better based on color, thickness, and discomfort. RESULTS Eighteen patients were enrolled, of which 13 patients completed the three phases of the study. After 6 weeks the wounds did not show a statistically significant difference in color, thickness, or discomfort on either side. CONCLUSION Results obtained to date suggest that the application of tobramycin-dexamethasone ointment to wounds after dermatologic surgery does not promote better wound healing than white petrolatum. These findings indicate that a topical steroid and antibiotic ointment may not be an effective intervention in improving postoperative outcomes in dermatologic surgeries.
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Affiliation(s)
- Rachel Andrew
- University of Texas Southwestern Medical Center, Dallas, TX 75390 USA
| | - Gwendolyn Luecke
- University of Texas Southwestern Medical Center, Dallas, TX 75390 USA
| | - Susan Dozier
- Department of Dermatology, University of Texas Southwestern Austin Program, Dallas, TX 75390 USA
| | - Dayna G. Diven
- Department of Dermatology, University of Texas Southwestern Austin Program, Dallas, TX 75390 USA
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Czerwinski SL, Lyon AW, Skorobohach B, Léguillette R. Pharmacokinetic analysis of topical tobramycin in equine tears by automated immunoassay. BMC Vet Res 2012; 8:141. [PMID: 22909398 PMCID: PMC3489562 DOI: 10.1186/1746-6148-8-141] [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: 03/28/2012] [Accepted: 08/14/2012] [Indexed: 11/24/2022] Open
Abstract
Background Ophthalmic antibiotic therapy in large animals is often used empirically because of the lack of pharmacokinetics studies. The purpose of the study was to determine the pharmacokinetics of topical tobramycin 0.3% ophthalmic solution in the tears of normal horses using an automated immunoassay analysis. Results The mean tobramycin concentrations in the tears at 5, 10, 15, 30 minutes and 1, 2, 4, 6 hours after administration were 759 (±414), 489 (±237), 346 (±227), 147 (±264), 27.6 (±28.4), 14.8 (±66.6), 6.7 (±18.6), and 23.4 (±73.4) mg/L. Mean tobramycin concentration was maintained above the MIC90 for commonly isolated bacteria for 68.5 min. Conclusion A single dose of topical tobramycin resulted in therapeutic concentrations of tobramycin in the tears for 1 h after administration. Therapeutic levels of tobramycin remained in equine tears 6 times longer than was reported in rabbit tears.
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Affiliation(s)
- Sarah L Czerwinski
- Department of Veterinary Clinical and Diagnostic Sciences, Faculty of Veterinary Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
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The effectiveness of an improved combination therapy for experimental Staphylococcus aureus keratitis. Adv Ther 2010; 27:933-40. [PMID: 21046494 DOI: 10.1007/s12325-010-0082-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Indexed: 10/18/2022]
Abstract
INTRODUCTION antibiotic and steroid combination therapies, such as tobramycin with dexamethasone, are often used in ophthalmology to treat or prevent infection and inflammation. The purpose of this study was to use a model of Staphylococcus aureus keratitis to quantify and compare the effectiveness of a standard tobramycin and dexamethasone combined therapy, with each drug individually, and with a new formulation of the two drugs in a xanthan gum vehicle. METHODS rabbit corneas were intrastromally injected with a methicillin-sensitive S. aureus (MSSA) or a methicillin-resistant S. aureus (MRSA) strain. Rabbit eyes were treated every hour from 10 to 15 hours postinfection (PI) with 0.1% dexamethasone, 0.3% tobramycin, 0.3% tobramycin with 0.1% dexamethasone, or 0.3% tobramycin with 0.05% dexamethasone in a xanthan gum vehicle (ST). Slit lamp examinations (SLE) were performed on infected eyes and pathology scored at 15 hours PI. At 16 hours PI, colony forming units (CFUs) per cornea were quantified. RESULTS the CFUs in eyes treated with dexamethasone alone were similar to untreated control eyes for MSSA or MRSA infections. All other treatment groups had significantly less CFUs per cornea than untreated eyes. The eyes treated with the ST formulation had significantly fewer CFUs per cornea than all other treatment groups when infected with MSSA or MRSA. The SLE scores of MSSA or MRSA infected eyes treated with tobramycin alone were similar to untreated control eyes. All other treatment groups had significantly lower SLE scores than untreated controls eyes, but were not significantly different from each other. CONCLUSION the results of this study demonstrated that the tobramycin and dexamethasone combination therapy with a xanthan gum vehicle has an improved bactericidal effectiveness compared to the commercially available formulation, and maintains a similar anti-inflammatory effect while containing half the amount of steroid.
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