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Dive into the research topics where Ken Green is active.

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Featured researches published by Ken Green.


Ophthalmology | 2012

Sustained Delivery Fluocinolone Acetonide Vitreous Inserts Provide Benefit for at Least 3 Years in Patients with Diabetic Macular Edema

Peter A. Campochiaro; David M. Brown; Andrew Pearson; Sanford Chen; David S. Boyer; José M. Ruiz-Moreno; Bruce R Garretson; Amod Gupta; Seenu M. Hariprasad; Clare Bailey; Elias Reichel; G. Soubrane; Barry Kapik; Kathleen Billman; Ken Green

OBJECTIVE To assess long-term efficacy and safety of intravitreal inserts releasing 0.2 μg/d (low dose) or 0.5 μg/d (high dose) fluocinolone acetonide (FAc) in patients with diabetic macular edema (DME). DESIGN Two randomized, sham injection-controlled, double-masked, multicenter clinical trials. PARTICIPANTS Subjects with persistent DME despite ≥1 macular laser treatment were randomized 1:2:2 to sham injection (n = 185), low-dose insert (n = 375), or high-dose insert (n = 393). METHODS Subjects received study drug or sham injection and after 6 weeks were eligible for rescue laser. Based on retreatment criteria, additional study drug or sham injections could be given after 1 year. MAIN OUTCOME MEASURES Percentage of patients with improvement of ≥15 letters from baseline. Secondary outcomes included other parameters of visual function and foveal thickness. RESULTS At month 36, the percentage of patients who gained ≥15 in letter score using the last observation carried forward method was 28.7% (low dose) and 27.8% (high dose) in the FAc insert groups compared with 18.9% (P = 0.018) in the sham group, and considering only those patients still in the trial at month 36, it was 33.0% (low dose) and 31.9% (high dose) compared with 21.4% in the sham group (P = 0.030). Preplanned subgroup analysis demonstrated a doubling of benefit compared with sham injections in patients who reported duration of DME ≥3 years at baseline; the percentage who gained ≥15 in letter score at month 36 was 34.0% (low dose; P<0.001) or 28.8% (high dose; P = 0.002) compared with 13.4% (sham). An improvement ≥2 steps in the Early Treatment Diabetic Retinopathy Study retinopathy scale occurred in 13.7% (low dose) and 10.1% (high dose) compared with 8.9% in the sham group. Almost all phakic patients in the FAc insert groups developed cataract, but their visual benefit after cataract surgery was similar to that in pseudophakic patients. The incidence of incisional glaucoma surgery at month 36 was 4.8% in the low-dose group and 8.1% in the high-dose insert group. CONCLUSIONS In patients with DME FAc inserts provide substantial visual benefit for up to 3 years and would provide a valuable addition to the options available for patients with DME.


Expert Opinion on Drug Delivery | 2008

Iluvien™: a new sustained delivery technology for posterior eye disease

Judith Burdan; Antonio Cutino; Ken Green

Iluvien™ (fluocinolone acetonide intravitreal insert, Alimera Sciences, Inc.), a novel injectable intravitreal insert, is being studied to deliver a very low dose of a corticosteroid to the retina for up to 3 years as a treatment for diabetic macular edema. Using a proprietary 25-gauge injector system, an ophthalmologist injects the Iluvien insert, which uses the Medidur™ (Alimera Sciences, Inc.) technology, into the vitreous through a minimally invasive procedure in an out-patient setting. The placement of the device in the inferior vitreous has the potential to maximize drug at the retina while reducing exposure of the anterior chamber. Phase III studies are underway to test the safety and efficacy of Iluvien. This article offers a specific review of the Iluvien technology rather than an overview of the various intravitreal methods of treating posterior eye disease.


Ophthalmology | 2010

Sustained Ocular Delivery of Fluocinolone Acetonide by an Intravitreal Insert

Peter A. Campochiaro; Gulnar Hafiz; Syed Mahmood Shah; Steven M. Bloom; David M. Brown; Miguel Busquets; Thomas A. Ciulla; Leonard Feiner; Nelson R. Sabates; Kathleen Billman; Barry Kapik; Ken Green

PURPOSE To compare Iluvien intravitreal inserts that release 0.2 or 0.5 microg/day of fluocinolone acetonide (FA) in patients with diabetic macular edema (DME). DESIGN Prospective, randomized, interventional, multicenter clinical trial. PARTICIPANTS We included 37 patients with DME. METHODS Subjects with persistent DME despite > or = 1 focal/grid laser therapy were randomized 1:1 to receive an intravitreal insertion of a 0.2- or a 0.5-microg/day insert. MAIN OUTCOME MEASURES The primary end point was aqueous levels of FA throughout the study with an important secondary outcome of the change from baseline in best-corrected visual acuity (BCVA) at month 12. RESULTS The mean aqueous level of FA peaked at 3.8 ng/ml at 1 week and 1 month after administration of a 0.5-microg/day insert and was 3.4 and 2.7 ng/ml 1 week and 1 month after administration of a 0.2-microg/day insert. For both inserts, FA levels decreased slowly thereafter and were approximately 1.5 ng/ml for each at month 12. The mean change from baseline in BCVA was 7.5, 6.9, and 5.7 letters at months 3, 6, and 12, respectively, after administration of a 0.5 microg/day-insert and was 5.1, 2.7, and 1.3 letters at months 3, 6, and 12, respectively, after administration of a 0.2-microg/day insert. There was a mild increase in mean intraocular pressure after administration of 0.5-microg/day inserts, but not after administration of 0.2-microg/day inserts. CONCLUSIONS The FA intravitreal inserts provide excellent sustained intraocular release of FA for > or = 1 year. Although the number of patients in this trial was small, the data suggest that the inserts provide reduction of edema and improvement in BCVA in patients with DME with mild effects on intraocular pressure over the span of 1 year. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found after the references.


Ophthalmology | 2014

Sustained Delivery Fluocinolone Acetonide Vitreous Implants: Long-Term Benefit in Patients with Chronic Diabetic Macular Edema

José Cunha-Vaz; Paul Ashton; Raymond Iezzi; Peter A. Campochiaro; Pravin U. Dugel; Frank G. Holz; Michel Weber; Ronald P. Danis; Baruch D. Kuppermann; Clare Bailey; Kathleen Billman; Barry Kapik; Ken Green

PURPOSE To present the safety and efficacy of intravitreal implants releasing 0.2 μg/day fluocinolone acetonide (FAc) in patients with chronic versus nonchronic diabetic macular edema (DME). To assess ocular characteristics, anatomic changes, and re-treatment and ancillary therapies that may explain the differential treatment effect seen with intravitreal implants releasing FAc 0.2 μg/day in patients with chronic and nonchronic DME. An overall benefit-to-risk assessment for the FAc 0.2-μg/day and FAc 0.5-μg/day doses has been reported previously. DESIGN Preplanned subgroup analysis of chronic (duration of diagnosis, ≥3 years) and nonchronic (duration of diagnosis, <3 years) DME in patients from 2 randomized, sham injection-controlled, double-masked, multicenter clinical trials. PARTICIPANTS Patients with persistent DME despite 1 or more macular laser treatment were randomized 1:2:2 to sham injection (n = 185), FAc 0.2 μg/day (n = 375), or FAc 0.5 μg/day (n = 393). METHODS Patients received study drug or sham injection and after 6 weeks were eligible for rescue laser. Based on re-treatment criteria, additional masked study drug could be given after 1 year. MAIN OUTCOME MEASURES Percentage of patients with improvement of 15 letters or more from baseline. Secondary outcomes included other parameters of visual function and foveal thickness. RESULTS At month 36, the difference between FAc 0.2 μg/day and sham control in the percentage of patients who gained 15 letters or more was significantly greater in chronic DME patients (FAc 0.2 μg/day, 34.0% vs. sham, 13.4%; P<0.001), compared with patients with nonchronic DME (FAc 0.2 μg/day, 22.3% vs. sham, 27.8%; P = 0.275). The greater response in patients with chronic DME was not associated with baseline ocular characteristics, changes in anatomic features, or differences in re-treatment or ancillary therapies. The ocular adverse event profile for FAc 0.2 μg/day was similar regardless of DME duration. CONCLUSIONS This is the first published analysis correlating duration of diagnosis of DME with treatment effect. In patients with chronic DME, FAc 0.2 μg/day provides substantial visual benefit for up to 3 years and would provide an option for patients who do not respond to other therapy.


Ophthalmology | 2013

Aqueous Levels of Fluocinolone Acetonide after Administration of Fluocinolone Acetonide Inserts or Fluocinolone Acetonide Implants

Peter A. Campochiaro; Quan Dong Nguyen; Gulnar Hafiz; Steven M. Bloom; David M. Brown; Miguel Busquets; Thomas A. Ciulla; Leonard Feiner; Nelson R. Sabates; Kathleen Billman; Barry Kapik; Ken Green

PURPOSE To compare aqueous levels of fluocinolone acetonide (FAc) after administration of FAc inserts or FAc implants (Retisert; Bausch & Lomb, Rochester, NY). DESIGN Comparison of pharmacokinetics from 2 prospective, interventional, clinical trials. PARTICIPANTS Thirty-seven patients with diabetic macular edema (DME) (Fluocinolone Acetonide in Human Aqueous [FAMOUS] Study, C-01-06-002) and 7 patients with uveitis (NA-00019318). METHODS Aqueous FAc was measured after administration of FAc implants or 0.2 μg/day (low dose, ILUVIEN; Alimera Sciences Inc., Alpharetta, GA) or 0.5 μg/day (high dose) FAc inserts. MAIN OUTCOME MEASURES The primary end point was aqueous levels of FAc. RESULTS At 1 month after administration for subjects who received 1 treatment, mean aqueous FAc levels were 2.17 (low dose) and 3.03 ng/ml (high dose) for FAc inserts and 6.12 ng/ml for FAc implants with maximum levels of 3.83, 6.66, and 13.50 ng/ml, respectively. At 3 months, mean FAc levels were 1.76, 2.15, and 6.12 ng/ml, respectively. Between 6 and 36 months after low-dose inserts, aqueous levels of FAc were remarkably stable, ranging from 1.18 to 0.45 ng/ml. After high-dose inserts, mean FAc levels were stable between 6 and 24 months, ranging from 1.50 to 0.84 ng/ml and then decreasing to 0.35 ng/ml at 30 months and 0.15 ng/ml at 36 months. In implant-containing eyes, mean FAc levels remained >6 ng/ml through 15 months, the last time point with measurements from at least 6 eyes. CONCLUSIONS Low- and high-dose FAc inserts both provide stable long-term release of FAc with comparable peak levels in the aqueous: slightly >2 ng/ml for approximately 3 months followed by steady-state levels between 1.0 and 0.5 ng/ml through 36 months for low-dose inserts versus levels between 1.5 and 1.1 ng/ml through 24 months for high-dose inserts. Steady-state aqueous levels after FAc implants were >6 ng/ml. These results provide new insights that aid in the interpretation of efficacy trials and indicate that there is a dose effect for steroid-induced ocular hypertension. In susceptible patients, prolonged aqueous levels of FAc >1 ng/ml moderately increased the risk of glaucoma and levels >6 ng/ml posed a markedly increase risk.


Journal of Ocular Pharmacology and Therapeutics | 2015

Ocular pharmacokinetics of fluocinolone acetonide following Iluvien implantation in the vitreous humor of rabbits.

Ken Green

PURPOSE The purpose of this study was to evaluate the systemic and ocular pharmacokinetics (PK) of fluocinolone acetonide (FAc) following administration of Iluvien(®) intravitreal implants. METHODS The FAc intravitreal implant was administered to rabbits in 3 doses (0.2, 0.5, and 1.0 μg/day). The concentration of FAc was measured by a validated liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) method in plasma and ocular tissues at various time points through month 24. RESULTS Following administration of the 0.2 μg/day implant, FAc levels peaked in most tissues at day 2 or 8, reached approximate steady state levels by month 3 and very gradually decreased over the duration of the study. The FAc level in the aqueous humor was not measurable at most time points in the rabbit. FAc was still present in most ocular tissues at 2 years. The 0.5 and 1.0 μg/day dose groups followed the same pattern through month 9. The elimination half lives in the tissues for which it was measurable were greater than 83 days. Exposure to FAc was highest in the choroid/retinal pigment epithelium for all doses, followed by lens and retina. CONCLUSIONS The results of this study demonstrate sustained delivery of FAc from the Iluvien intravitreal implant in the ocular tissue of rabbits. Retina and lens FAc levels with the Iluvien implant were approximately 1/10 those reported with the Retisert(®) implant. FAc levels in the aqueous were not measureable with Iluvien where they were measured for 12 months with Retisert.


Ophthalmic Surgery and Lasers | 2016

Characterization of Intraocular Pressure Increases and Management Strategies Following Treatment With Fluocinolone Acetonide Intravitreal Implants in the FAME Trials

Richard K. Parrish; Peter A. Campochiaro; P. Andrew Pearson; Ken Green; Carlo Enrico Traverso

BACKGROUND AND OBJECTIVE To compare elevated intraocular pressure (IOP) management and outcomes among patients with diabetic macular edema who received fluocinolone acetonide (FAc) implants versus sham-control treatment and explore the prior ocular steroid exposure impact on IOP outcomes. PATIENTS AND METHODS Best-corrected visual acuity (BCVA) was measured using Early Treatment Diabetic Retinopathy Study charts or electronic VA testers. Goldmann applanation tonometry was used to measure IOP. RESULTS Elevated IOP was more common in FAc-versus sham control-treated patients. Medication, and less often trabeculoplasty or surgery, was used to lower IOP without affecting VA outcomes. No patient treated with 0.2 µg/day FAc who received prior ocular steroid required IOP-lowering surgery. CONCLUSION Elevated IOP may occur following FAc implant receipt; however, in the present study, it was manageable and did not impact vision outcomes. Patients previously treated with ocular steroid did not require IOP-lowering surgery following 0.2 µg/day FAc implant administration. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:426-435.].


Ophthalmic Surgery and Lasers | 2016

Quantitative Assessment of Optic Nerve Changes in Patients With Diabetic Macular Edema Treated With Fluocinolone Acetonide Vitreous Implants

Richard K. Parrish; Carlo Enrico Traverso; Ken Green; Ronald P. Danis

BACKGROUND AND OBJECTIVE To evaluate glaucomatous changes in patients with diabetic macular edema (DME) treated with intravitreal implants releasing 0.2 µg/day or 0.5 µg/day fluocinolone acetonide (FAc) (Iluvien 0.2 µg/day; Alimera Sciences, Alpharetta, GA) or sham control. PATIENTS AND METHODS Fundus photographs were assessed to determine clinically significant changes in glaucomatous indicators. RESULTS The mean cup-to-disc ratio (CDR) change was similar with all three treatments. Compared with sham control, a significantly greater proportion of patients treated with 0.5 µg/day but not 0.2 µg/day FAc experienced a CDR increase of greater than 0.1. There was no significant increase in the proportion of patients experiencing a CDR increase of greater than 0.2 with either dose of implant versus sham control. Other indicators of glaucomatous change did not differ significantly with treatment. Subgroup analyses showed no differences in cupping based on ocular or baseline characteristics. CONCLUSION Treatment with FAc for 36 months was not associated with significant glaucomatous optic nerve head changes in patients with DME with or without increased intraocular pressure. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:418-425.].


Journal of Neurochemistry | 2018

Metipranolol Promotes Structure and Function of Retinal Photoreceptors in the rd10 Mouse Model of Human Retinitis Pigmentosa

Yogita Kanan; Mahmood Khan; Valeria E. Lorenc; Da Long; Rishi Chadha; Jason Sciamanna; Ken Green; Peter A. Campochiaro

Metipranolol is a β‐adrenergic receptor antagonist that is given orally for the treatment of hypertension and also applied topically to the cornea for treating glaucoma. It also inhibits nitrosative stress which has previously been shown to be the cause of cone photoreceptor death in retinitis pigmentosa. In this study, we tested the hypothesis that metipranolol protects photoreceptor structure and function in the mouse model rd10. At P35, compared with vehicle‐treated rd10 mice in which rod degeneration was nearly complete, rd10 mice given daily subcutaneous injections of 40 mg/kg of metipranolol had reduction in markers of nitrosative stress, fewer TUNEL‐positive cells, increased outer nuclear layer thickness, and substantially more staining for rhodopsin. This was accompanied by significantly higher mean scotopic and photopic electroretinogram b‐wave amplitudes indicating improved photoreceptor function. At P50, metipranolol‐treated rd10 mice had decreased 3‐nitrotyrosine staining in the retina, increased immunostaining for cone arrestin, a marker for cone photoreceptors, and significantly higher scotopic and photopic b‐wave amplitudes at the highest stimulus intensity compared with vehicle‐treated mice. At P65, cone density was significantly higher in metipranolol‐treated versus vehicle‐injected rd10 mice. Metipranolol applied as eye drops promoted cone photoreceptor function in retinas of rd10 mice greater than subcutaneously injected metipranolol. The reduced nitrosative damage and rescue of functional loss of photoreceptors in rd10 mice suggests that metipranolol, a drug with established ocular safety and tolerability, may have potential for treating patients with retinitis pigmentosa.


Ophthalmology | 2017

Long-term Effects of Intravitreal 0.19 mg Fluocinolone Acetonide Implant on Progression and Regression of Diabetic Retinopathy

Charles C. Wykoff; Usha Chakravarthy; Peter A. Campochiaro; Clare Bailey; Ken Green; José Cunha-Vaz

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Clare Bailey

University Hospitals Bristol NHS Foundation Trust

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Gulnar Hafiz

Johns Hopkins University School of Medicine

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Leonard Feiner

Hackensack University Medical Center

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Nelson R. Sabates

University of Missouri–Kansas City

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