Long-term effectiveness of ranibizumab for age-related macular degeneration and diabetic macular edema

Anti-VEGF Drugs in Age-Related Macular Degeneration: A Focus on Dosing Regimen-Related Safety and Efficacy

Age-related macular degeneration (AMD) is one of the main causes of visual impairment and severe visual loss, and can progress to two advanced forms-neovascularization and atrophic. The field of anti-AMD drugs has undergone huge developments in recent years, from single-target intravitreal administration to current clinical studies with multi-target and non-invasive agents, offering interesting new pharmacological opportunities for the treatment of this disease. Hence, we summarize some of the approved anti-vascular endothelial growth factor (VEGF) drugs for neovascular AMD, especially their structural characteristics, clinical manifestations, dosing regimens, and safety issues of the anti-VEGF drugs highlighted. In addition, advances in atrophic AMD drug research are also briefly described.

Levodopa Positively Affects Neovascular Age-Related Macular Degeneration

BACKGROUND

Age-related macular degeneration (AMD) is a common cause of blindness worldwide. Neovascular AMD (nAMD) is an advanced form of the disease, in which excess vascular endothelial growth factor (VEGF) induces growth of new blood vessels that leak fluid, accounting for 90% of vision loss in AMD. Dysfunction of the retinal pigment epithelium likely initiates AMD. Retinal pigment epithelial cells express a G protein-coupled receptor, GPR143, which downregulates VEGF in response to levodopa. Anti-VEGF therapy effectively treats nAMD, suggesting that excessive VEGF activity drives the pathology.

METHODS

In an open-label pilot study, in patients with newly diagnosed nAMD and naïve to anti-VEGF injections (Cohort-1), the effects of carbidopa-levodopa on vision and anatomic outcomes were evaluated for 4 weeks. Then patients were followed 5 months further with ascending levodopa doses. Patients previously treated with anti-VEGF injection therapy (Cohort-2) were also treated with ascending levodopa doses and evaluated for 6 months.

RESULTS

Levodopa was safe, well tolerated, and delayed anti-VEGF injection therapy while improving visual outcomes. In the first month, retinal fluid decreased by 29% (P = .02, n = 12) without anti-VEGF treatment. Through 6 months the decrease in retinal fluid was sustained, with a mean frequency of 0.38 injections/month. At month 6, mean visual acuity improved by 4.7 letters in Cohort-1 (P = .004, n = 15) and by 4.8 letters in Cohort-2 (P = .02, n = 11). Additionally, there was a 52% reduction in the need for anti-VEGF injections in Cohort-2 (P = .002).

CONCLUSIONS

Our findings suggest efficacy and support the pharmacological targeting of GPR143 with levodopa for the treatment of nAMD in future studies.

The Short-term Effect of a Single Lapse in Anti-Vascular Endothelial Growth Factor Treatment for Diabetic Macular Edema Within Routine Clinical Practice

Purpose

Diabetic macular edema (DME) is a leading cause of vision loss in diabetics. Anti–vascular endothelial growth factor (VEGF) therapy has been shown to be an effective treatment option for DME, although the injections are costly and require frequent visits, which increases the risk for unintended treatment lapses. The aim of this study is to characterize the effects of an unintended treatment lapse in patients with DME undergoing anti-VEGF therapy.

Design

Retrospective, comparative case series.

Methods

This retrospective chart review compared patients seen in a multicenter institutional practice with DME exhibiting an unintended minimum 3-month lapse in anti-VEGF treatment, with a control group of DME patients receiving regular anti-VEGF treatment without lapses. The primary outcome was difference in central subfield thickness (CST) between the control group and the treatment lapse group at 6 months following treatment lapse.

Results

A total of 164 patients were evaluated, 82 patients in the treatment lapse group and 82 patients in the control group. The average age was 65 years, and the average lapse in treatment was 6.2 ± 3.5 months (range 3-24 months). Comparison of data between the lapse and control groups revealed no significant differences in CST (359.9 ± 108.3 μm and 335.4±94.6 μm, respectively, P = .066) or in visual acuity (66.5 ± 14.3 and 68.9 ± 14.5, respectively, P = .136). Limitations included a relatively small sample size, retrospective nature, and only a single lapse being evaluated.

Conclusions

An unintended, single, relatively short-term lapse in anti-VEGF treatment in patients with DME did not appear to result in significant anatomic or visual compromise upon resumption of regular follow-up and treatment.

Can Vitreous Reflux Affect The Short-Term Treatment Response After Intravitreal Ranibizumab Injection?

PURPOSE

The aim of this study was to evaluate the effect of vitreous reflux (VR) on the short-term effect of intravitreal ranibizumab injection.

MATERIALS AND METHODS

The study included 181 eyes of 81 age-related macular degeneration (AMD) and 100 diabetic macular edema (DME) patients. Treatment response was evaluated by measuring central macular thickness (CMT) as well as 1 mm and 3 mm central macular thicknesses (MT1 and MT3). Patients were grouped as; Group 1: no VR, Group 2: <3 mm VR, and Group 3: >3 mm VR according to conjunctival bleb diameters. The data were analyzed using variance, correlation and regression analyses.

RESULTS

In AMD patients, reduction of CMT values following the treatment were 88.3 ± 110.6 µm in Group 1, 85.6 ± 158.7 µm in Group 2, and 93.1 ± 92.2 µm in Group 3. Likewise, in DME patients, it was 82.4 ± 88.4 µm, 72.9 ± 109.9 µm, and 73.7 ± 113.7 µm, respectively. Reduction of MT1 values after the treatment were 47.4 ± 72.6 µm, 36.0 ± 131.9 µm, and 36.7 ± 114.4 µm in AMD patients, and 33.3 ± 72.5 µm, 36.6 ± 90.2 µm, and 46.9 ± 83.4 µm in DME patients. In all comparisons among groups of VR, macular thickness (MT) change did not exhibit significant difference following an intravitreal ranibizumab treatment (p > .05).

CONCLUSION

We found that the increase in VR amount did not adversely affect the decrease in MT after intravitreal ranibizumab treatment in AMD and DME patients.

Proteomic Biomarkers of Retinal Inflammation in Diabetic Retinopathy

Diabetic retinopathy (DR), a sight-threatening neurovasculopathy, is the leading cause of irreversible blindness in the developed world. DR arises as the result of prolonged hyperglycemia and is characterized by leaky retinal vasculature, retinal ischemia, retinal inflammation, angiogenesis, and neovascularization. The number of DR patients is growing with an increase in the elderly population, and therapeutic approaches are limited, therefore, new therapies to prevent retinal injury and enhance repair are a critical unmet need. Besides vascular endothelial growth factor (VEGF)-induced vascular proliferation, several other mechanisms are important in the pathogenesis of diabetic retinopathy, including vascular inflammation. Thus, combining anti-VEGF therapy with other new therapies targeting these pathophysiological pathways of DR may further optimize treatment outcomes. Technological advancements have allowed for high-throughput proteomic studies examining biofluids such as aqueous humor, vitreous humor, tear, and serum. Many DR biomarkers have been identified, especially proteins involved in retinal inflammatory processes. This review attempts to summarize the proteomic biomarkers of DR-associated retinal inflammation identified over the last several years.

Omega-3 and ranibizumab for age-related macular degeneration: A systematic review protocol

BACKGROUND

Omega-3 and ranibizumab (O3R) has been reported to treat age-related macular degeneration (ARMD) effectively. However, up to the present, no systematic review specifically addressed the efficacy of O3R for the treatment of ARMD. Therefore, in this study, we will propose to assess the efficacy and safety of O3R for the treatment of ARMD.

METHODS

We will search PUMBED, EMBASE, CINAHI, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, Cochrane Library, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, VIP Information, Wanfang Data, as well as the gray literature from inception up to the present. We will accept randomized controlled trials for assessing the efficacy and safety of O3R for ARMD. The primary outcomes include change in best corrected visual acuity and central retinal thickness. The secondary outcomes consist of changes in subfoveal choroidal thickness, macular atrophy, retinal average sensitivity, contrast sensitivity, glare disability, and quality of life. In addition, incidence and severity of adverse events will also be evaluated. Cochrane Collaboration tool will be used to assess the risk of bias for each included study. In addition, Grading of Recommendations Assessment, Development, and Evaluation tool will be utilized to assess the overall strength of the evidence. Two authors will independently carry out all procedures and any divergences will be solved through discussion with a third author. If it is possible, we will conduct meta-analysis and subgroup analysis concerning different interventions, risk of bias, and outcome measurements.

RESULTS

In this proposed study, we outline details of the aims and methods of efficacy and safety of O3R for the treatment of ARMD.

CONCLUSION

The findings of this systematic review will summarize current evidence of O3R for the treatment of patients with ARMD.

DISSEMINATION AND ETHICS

The results of the present study are expected to be published by peer-reviewed journals. This is a literature-based study. Thus, ethical approval is unnecessary for this study.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019121177.

Time-dependent changes in hypoxia- and gliosis-related factors in experimental diabetic retinopathy

Diabetes causes various biochemical changes in the retina; long-term changes in the factors associated with hypoxia and gliosis have rarely been reported. The present study was conducted to explore the changes in these factors in a time-dependent manner in experimental diabetic retinopathy (DR). Diabetes was induced in Sprague-Dawley rats by intraperitoneal injection of streptozotocin. The expression of the following factors was examined using immunofluorescence and western blot analysis at 0.5, 1, 2, 4 and 6 months after diabetes onset: hypoxia-inducible factor-1alpha (HIF-1alpha), vascular endothelial growth factor (VEGF), erythropoietin (EPO), erythropoietin receptor (EPOR), glial fibrillary acidic protein (GFAP), vimentin, glutamate-aspartate transporter (GLAST) and glutamine synthase (GS). The expression of factors such as HIF-1alpha, VEGF, EPO, EPOR, GFAP and vimentin, was up-regulated with the progression of diabetes in the diabetic rat retinas compared to the expression in normal control retinas, whereas the expression of GS and GLAST was down-regulated. Changes in EPO and EPOR appeared 2 weeks after diabetes onset. HIF-1alpha, VEGF and GFAP started to increase at 1 month and vimentin at 4 months after diabetes onset. GS and GLAST started to decrease at 1 month after diabetes onset. The expression of these factors, which are involved in the processes of hypoxia and gliosis, varied at different stages of DR. The time-course change may be helpful in the evaluation of the progression of DR, and it may indicate the optimal intervention time points for DR.

Inflammatory mediators in the vitreal reflux of patients with diabetic macular edema

PURPOSE

To quantify inflammatory, growth/angiogenic, and tissue remodeling mediators in vitreal reflux (VR) in patients with diabetic macular edema (DME), as collected at first and third intravitreal anti-vascular endothelial growth factor (anti-VEGF, ranibizumab) injection.

METHODS

Thirty (30) consecutive patients (type-2 diabetes mellitus) with visual impairments due to DME and undergoing the first (untreated DME) or the third (treated DME) intravitreal injection of anti-VEGF were included in the study. At the time of surgery, patients were subjected to clinical assessment and spectral domain-optical coherence tomography (SD-OCT), including central retinal thickness (CRT), macular volume, and outer nuclear layer/retinal pigment epithelial (ONL/RPE) measurements. VR sampling was performed at the time of needle removal and subjected to customized protein-array, Western blotting (WB), Ella™ microfluidic, and/or enzyme-linked immunosorbent assay (ELISA) analysis. Biostrumental and biochemical data were collected just prior to the surgery and are representative of disease state. Clinical, biostrumental, and numerous biomarkers and cytokines were statistically compared.

RESULTS

Decreased CRT values were detected in treated DME retinas, as compared to untreated ones (p ≤ 0.05). Differences in VEGF and other mediator expressions between treated and untreated DME were detected in VR samples. Particularly, osteopontin (p ≤ 0.05), interleukin 6 (IL6) (p ≤ 0.05), and VEGF (p ≤ 0.1) values were decreased after treatment. Significant changes were validated by WB, ELISA, and Ella™ analysis.

CONCLUSION

Overall, the biostrumental and biochemical data suggest the presence of a specific pattern of inflammation in VR after treatment. The data would suggest the presence of other mechanisms and mediators, in addition to VEGF, accountable for DME progression.

Intravitreal injections of anti-VEGF agents and antibiotic prophylaxis for endophthalmitis: A systematic review and meta-analysis

We performed a systematic review and meta-analysis to determine whether the use of local antibiotics is a beneficial prophylactic treatment for endophthalmitis in patients treated with anti-VEGF agents. We searched the MEDLINE and EMBASE databases, and the Cochrane Library over the period January 2007 to December 2016. The search terms used included “Endophthalmitis”, “Antibiotic” and “Intravitreal injection”. Studies in which the patients were treated exclusively with intravitreal injections of anti-VEGF were selected. Eight studies fit the inclusion criteria, which included a total of 276,774 injections; 109,178 (39.45%) were associated with the use of antibiotics and 114,821 (60.55%) were not associated with the use of antibiotics. Our meta-analysis indicated a significant risk for endophthalmitis that was 1.70 times greater with the use of antibiotics than that without antibiotics, with a confidence interval of 1.08 to 2.66 (p = 0.02). A meta-regression indicated that the location (operating rooms versus outpatient clinics) of injection did not have a significant effect on the incidence of endophthalmitis. The prophylactic use of antibiotics when administering anti-VEGF intravitreal injections may contribute to a greater incidence of endophthalmitis. This finding, in addition to reducing costs, would eliminate a treatment that has been shown to be unnecessary and even harmful to patients.

Treatment of age-related neovascular macular degeneration: the patient's perspective

OBJECTIVES

The aim of this study was to assess patients' views and expectations with regard to neovascular age-related macular degeneration (nAMD) and intravitreal anti-VEGF therapy (IVT).

METHODS

We conducted a multicenter, non-interventional, prospective cohort study including nAMD patients treated with IVT in Germany. Patients with at least one IVT before study enrollment and aged ≥50 years were included. Three telephone interviews were conducted during a 12-month observational period. Here, patient's beliefs/expectations with regard to the nAMD disease and the IVT treatment were discussed. Only patients who completed all three phone interviews were included in the analyses. We used a two-step cluster analysis to identify patient clusters regarding specific patient attitudes towards nAMD and its treatment.

RESULTS

Three hundred and thirty-two patients completed all interviews (mean age of 76.4 ± 7.2 years, 59.0% women). Out of these, 57.8% acknowledged that they needed general assistance in daily life, while 77.4% stated being able to attend general medical appointments on their own. However, 64.7% needed a driver or an accompanying person to attend their IVT appointments. In addition, 3.9% of the patients were afraid of IVT side effects. Also, 87.3% and 43.1% of the patients could name their disease or the anti-VEGF drug administered, respectively. More than three-quarters of the patients (83.1%) were aware of possible consequences of nAMD by stating vision loss or blindness, but only 16.6% knew that nAMD is a chronic disease. Generally, patients were optimistic: 70.2%, 5.1% and 13.0% of them expected stable visual acuity (VA), a significant improvement or expected worsening of VA in the next year, respectively. Almost two thirds of patients who provided their therapy expectations (47.0%) anticipated fewer injections/discontinuation of IVT. We identified five patient clusters differing significantly from each other with regard to four variables: being afraid of IVT, nAMD disease awareness, optimism with regard to effectiveness of IVT, and nAMD disease and treatment knowledge.

CONCLUSIONS

Only a minority of patients is aware of the chronic nature of nAMD. To motivate patients to accept a life-long IVT treatment, physicians and caregivers must know that there exist different patient types with significant differences in communication needs.

Editing VEGFR2 Blocks VEGF-Induced Activation of Akt and Tube Formation

Purpose

Vascular endothelial growth factor receptor 2 (VEGFR2) plays a key role in VEGF-induced angiogenesis. The goal of this project was to test the hypothesis that editing genomic VEGFR2 loci using the technology of clustered regularly interspaced palindromic repeats (CRISPR)-associated DNA endonuclease (Cas)9 in Streptococcus pyogenes (SpCas9) was able to block VEGF-induced activation of Akt and tube formation.

Methods

Four 20 nucleotides for synthesizing single-guide RNAs based on human genomic VEGFR2 exon 3 loci were selected and cloned into a lentiCRISPR v2 vector, respectively. The DNA fragments from the genomic VEGFR2 exon 3 of transduced primary human retinal microvascular endothelial cells (HRECs) were analyzed by Sanger DNA sequencing, surveyor nuclease assay, and next-generation sequencing (NGS). In the transduced cells, expression of VEGFR2 and VEGF-stimulated signaling events (e.g., Akt phosphorylation) were determined by Western blot analyses; VEGF-induced cellular responses (proliferation, migration, and tube formation) were examined.

Results

In the VEGFR2-sgRNA/SpCas9–transduced HRECs, Sanger DNA sequencing indicated that there were mutations, and NGS demonstrated that there were 83.57% insertion and deletions in the genomic VEGFR2 locus; expression of VEGFR2 was depleted in the VEGFR2-sgRNA/SpCas9–transduced HRECs. In addition, there were lower levels of Akt phosphorylation in HRECs with VEGFR2-sgRNA/SpCas9 than those with LacZ-sgRNA/SpCas9, and there was less VEGF-stimulated Akt activation, proliferation, migration, or tube formation in the VEGFR2-depleted HRECs than those treated with aflibercept or ranibizumab.

Conclusions

The CRISPR-SpCas9 technology is a potential novel approach to prevention of pathologic angiogenesis.

Effect of intravitreal injection of ranibizumab on retinal ganglion cells and microvessels in the early stage of diabetic retinopathy in rats with streptozotocin-induced diabetes

The aim of the present study was to investigate the effect of intravitreal injection of ranibizumab on retinal ganglion cells and microvessels at the early stage of diabetic retinopathy (DR) in rats with streptozotocin-induced diabetes mellitus (DM). DM was induced by a single intraperitoneal injection of 60 mg/kg body weight streptozotocin. A total of 80 diabetic rats were randomly assigned to four treatment groups (n=20 in each group) and were treated with an oculus dexter intravitreal injection of ranibizumab. Groups A and B were injected with ranibizumab two and four weeks after DM-induction, respectively, while groups a and b (controls) were injected with phosphate-buffered saline at the same time points. In addition, 20 normal rats were assigned to group N (blank control; without intraocular injection). Vitreous humors were isolated for vascular endothelial growth factor (VEGF)-A ELISA and retinas were obtained for hematoxylin and eosin staining, periodic acid-Schiff staining and fluorescence imaging techniques at six and eight weeks after the onset of DM. At six and eight weeks, a significantly increased in retinal ganglion cells (RGCs) was observed in group A compared with group a (P<0.01), and in group B compared with group b (P<0.01). In addition, there was a significant difference in the RGC level between groups A and B at six weeks after DM induction (P<0.01), but not at eight weeks (P>0.05). VEGF-A concentrations in rat vitreous humors were significantly lower in groups A and B compared with groups a and b at six and eight weeks after DM induction (P<0.01). Furthermore, the ratio of endotheliocytes to pericytes in groups A and B was significantly lower compared with groups a and b at six and eight weeks (P<0.05). Furthermore, it was also demonstrated that type IV collagen-positive strands were not present in group A during the eight-week observation period, which was significantly different from groups a, b and B (P<0.01). In conclusion, intravitreal injection of ranibizumab at a very early stage of DR in streptozotocin-induced DM rats slowed the progression of DR by reducing vascular regression or damage and maintaining RGC numbers, as well as reducing VEGF-A concentrations.

Application of aptamers in diagnostics, drug-delivery and imaging

Aptamers are small, single-stranded oligonucleotides (DNA or RNA) that bind to their target with high specificity and affinity. Although aptamers are analogous to antibodies for a wide range of target recognition and variety of applications, they have significant advantages over antibodies. Since aptamers have recently emerged as a class of biomolecules with an application in a wide array of fields, we need to summarize the latest developments herein. In this review we will discuss about the latest developments in using aptamers in diagnostics, drug delivery and imaging. We begin with diagnostics, discussing the application of aptamers for the detection of infective agents itself, antigens/ toxins (bacteria), biomarkers (cancer), or a combination. The ease of conjugation and labelling of aptamers makes them a potential tool for diagnostics. Also, due to the reduced off-target effects of aptamers, their use as a potential drug delivery tool is emerging rapidly. Hence, we discuss their use in targeted delivery in conjugation with siRNAs, nanoparticles, liposomes, drugs and antibodies. Finally, we discuss about the conjugation strategies applicable for RNA and DNA aptamers for imaging. Their stability and self-assembly after heating makes them superior over protein-based binding molecules in terms of labelling and conjugation strategies.

Antiangiogenic and Neurogenic Activities of Sleeping Beauty-Mediated PEDF-Transfected RPE Cells In Vitro and In Vivo

Pigment epithelium-derived factor (PEDF) is a potent multifunctional protein that inhibits angiogenesis and has neurogenic and neuroprotective properties. Since the wet form of age-related macular degeneration is characterized by choroidal neovascularization (CNV), PEDF would be an ideal candidate to inhibit CNV and support retinal pigment epithelial (RPE) cells. However, its short half-life has precluded its clinical use. To deliver PEDF to the subretinal space, we transfected RPE cells with the PEDF gene using the Sleeping Beauty transposon system. Transfected cells expressed and secreted biologically active recombinant PEDF (rPEDF). In cultures of human umbilical vein endothelial cells, rPEDF reduced VEGF-induced cumulative sprouting by ≥47%, decreased migration by 77%, and increased rate of apoptosis at least 3.4 times. rPEDF induced neurite outgrowth in neuroblastoma cells and protected ganglion and photoreceptor cells in organotypic retinal cultures. In a rat model of CNV, subretinal transplantation of PEDF-transfected cells led to a reduction of the CNV area by 48% 14 days after transplantation and decreased clinical significant lesions by 55% and 40% after 7 and 14 days, respectively. We showed that transplantation of pigment epithelial cells overexpressing PEDF can restore a permissive subretinal environment for RPE and photoreceptor maintenance, while inhibiting choroidal blood vessel growth.

Choosing preclinical study models of diabetic retinopathy: key problems for consideration

Diabetic retinopathy (DR) is the most common complication of diabetes mellitus in the eye. Although the clinical treatment for DR has already developed to a relative high level, there are still many urgent problems that need to be investigated in clinical and basic science. Currently, many in vivo animal models and in vitro culture systems have been applied to solve these problems. Many approaches have also been used to establish different DR models. However, till now, there has not been a single study model that can clearly and exactly mimic the developmental process of the human DR. Choosing the suitable model is important, not only for achieving our research goals smoothly, but also, to better match with different experimental proposals in the study. In this review, key problems for consideration in choosing study models of DR are discussed. These problems relate to clinical relevance, different approaches for establishing models, and choice of different species of animals as well as of the specific in vitro culture systems. Attending to these considerations will deepen the understanding on current study models and optimize the experimental design for the final goal of preventing DR.

Intravitreal injection of dexamethasone implant and ranibizumab in cystoid macular edema in the course of irvine-gass syndrome

PURPOSE

To evaluate the efficacy of 2 dexamethasone intravitreal implants and 1 ranibizumab intravitreal injection after a bilateral postoperative complication of cataract surgery as pseudophakic cystoid macular edema.

PATIENTS AND METHODS

A 70-year-old male patient with systemic hypertension developed a progressive cystoid macular edema (CME) in both eyes starting between 10 and 20 days after cataract surgery. Two intravitreal dexamethasone implants and 1 ranibizumab injection were administered; first in the right eye (RE) and then in the left eye (LE). The patient was checked for 1 whole week and then once a month for 5 months after the injections.

RESULTS

One month after the first dexamethasone implant in his RE, the spectral domain optical coherence tomography (SD-OCT) showed a progressive reduction of the foveal thickness until a complete resolution of the CME occurred, which was associated with an improvement of visual acuity. After 3 months, the SD-OCT showed a relapse of the CME, which was then treated with 1 injection of ranibizumab. One month after this injection, there was a complete resolution of the CME. A new CME in his RE was diagnosed 2 months after the last ranibizumab injection; it was treated with a new dexamethasone implant. A complete resolution of the CME was obtained; a normal foveal profile was still present 5 months after the last injection, and the best-corrected visual acuity was 20/20. His LE developed a CME 40 days after surgery. One intravitreal injection of ranibizumab was first administered in his LE, with a complete resolution of the CME at SD-OCT 2 weeks later. As observed in his RE, 40 days after the ranibizumab injection, there was a relapse of the CME that was treated with 1 intravitreal injection of dexamethasone implant. Five months later, the patient showed a worsening of the CME, but it was completely resolved with a second dexamethasone injection. After 3 months, the foveal thickness was back to normal with a BCVA of 20/20.

CONCLUSION

Treatment with dexamethasone implants (Ozurdex(®)) and ranibizumab injections (Lucentis(®)) induced a progressive reduction of our patient's CME after cataract surgery (Irvine-Gass syndrome) until a complete normal foveal thickness was restored and his visual function was improved despite the order of injections.

Ranibizumab for the treatment of degenerative ocular conditions

Degenerative ocular conditions, such as age-related macular degeneration, diabetic retinopathy, retinal vein occlusions, and myopic degeneration, have become a major public health problem and a leading cause of blindness in developed countries. Anti-vascular endothelial growth factor (VEGF) drugs seem to be an effective and safe treatment for these conditions. Ranibizumab, a humanized monoclonal antibody antigen-binding fragment, which inhibits all biologically active isoforms of VEGF-A, is still the gold standard treatment for the majority of these pathological entities. In this review, we present the results of the most important clinical trials concerning the efficacy and safety of ranibizumab for the treatment of degenerative ocular conditions.

One-Year Feasibility Study of Replenish MicroPump for Intravitreal Drug Delivery: A Pilot Study

PURPOSE

To determine the feasibility of the surgical procedure and to collect some safety data regarding the bioelectronics of a novel micro drug pump for intravitreal drug delivery in a Beagle dog model for up to 1 year.

METHODS

Thirteen Beagle dogs were assigned to two groups. The experimental group (n = 11) underwent pars plana implantation of MicroPump; the body of which was sutured episclerally, while its catheter was secured at a pars plana sclerotomy. The control group (n = 2) underwent sham surgeries in the form of a temporary suturing of the MicroPump, including placement of the pars plana tube. Baseline and follow-up exams included ophthalmic examination and imaging. The experimental animals were euthanized and explanted at predetermined time points after surgery (1, 3, and 12 months), while the control animals were euthanized at 3 months. All operated eyes were submitted for histopathology.

RESULTS

Eyes were scored according to a modified McDonald-Shadduck system and ophthalmic imaging. Neither the implanted eyes nor the control eyes showed clinically significant pathological changes beyond the expected surgical changes. The operated eyes showed neither significant inflammatory reaction nor tissue ingrowth through the sclerotomy site compared with the fellow eyes.

CONCLUSION

This study shows that the Replenish Posterior MicroPump could be successfully implanted with good safety profile in this animal model.

TRANSLATIONAL RELEVANCE

The results of this study in a Beagle dog model are supportive of the biocompatibility of Replenish MicroPump and pave the way to the use of these devices for ocular automated drug delivery after further testing in larger animal models.

Visual outcome of intravitreal ranibizumab for exudative age-related macular degeneration: timing and prognosis

Purpose

To describe 1-year clinical results of intravitreal ranibizumab treatment in patients with choroidal neovascularization secondary to exudative age-related macular degeneration (AMD) and to evaluate whether early treatment is a predictive value for prognosis of the disease.

Materials and methods

Clinical records were retrospectively reviewed of 104 eyes that underwent intravitreal ranibizumab therapy for exudative AMD. Patients were divided into two groups according to their symptom duration: group 1, <1 month; and group 2, 1–3 months. After three monthly injections, patients were examined monthly, and subsequent injections were performed as needed.

Results

There were 43 female (48.9%) and 45 males (51.1%). The follow-up time was 13.7±1.9 (12–19) months. The mean logarithm of minimum angle of resolution best-corrected visual acuity (BCVA) improved significantly, from 0.45±0.639 at baseline to 0.08±0.267 at 12 months in group 1, and from 1.06±0.687 at baseline to 0.75±0.563 at 12 months in group 2. The increase in BCVA was statistically significant in group 1 (P=0.009). The mean central retinal thickness (CRT) decreased significantly, from 355.13±119.93 μm at baseline to 250.85±45.48 μm at 12 months in group 1, and from 371.88±91.047 μm at baseline to 268.61±53.51 μm at 12 months in group 2. The decrease in CRT was statistically significant in group 1 (P=0.001).

Conclusion

Intravitreal ranibizumab therapy was effective in significantly increasing mean BVCA and reducing CRT. Shorter duration of AMD, as measured by the subjective duration of visual symptoms, is associated with better visual outcome after treatment.

Diabetic Retinopathy-Update on Prevention Techniques, Present Therapies, and New Leads

Diabetic retinopathy is the major ocular complication associated with diabetes, and represents the leading cause of legal blindness in the working-age population of developed countries. Although classically diagnosed based on abnormalities of the retinal microvasculature, diabetic retinopathy is now widely recognized as a neurovascular disease. While all patients with diabetes are at increased risk for eye disease including diabetic retinopathy, proactive measures, and timely intervention can prevent or delay subsequent vision loss. Systemic management of diabetes by combined control of glycemia, blood pressure, and serum lipid levels remains the most important method of preventing diabetic retinopathy onset and progression. Once detected, surgical and medical interventions including photocoagulation, vitrectomy, and intravitral drug injection can help preserve vision. However, the need for improved detection methods and therapies that will allow earlier diagnosis and treatment remains apparent. This review summarizes current techniques for the prevention and intervention for diabetic retinopathy, and examines ongoing developments in the search for new endpoints and therapies as they apply to preventing vision loss associated with diabetes.

Translational vitreous proteomics

The vitreous is an extracellular matrix that is still poorly understood. Although many constituents and characteristics have been previously determined, there are many attributes still being discovered. Currently, using protein arrays, MS, and bioinformatics, the vitreous provides a wealth of knowledge regarding ocular diseases and potential targets for personalized therapeutics.