Combination Therapy for Neovascular Age-related Macular Degeneration Refractory to Anti-Vascular Endothelial Growth Factor Agents

Evaluating photodynamic therapy versus brolucizumab as a second-line treatment for polypoidal choroidal vasculopathy

BACKGROUND

To compare the one-year outcomes between intravitreal brolucizumab (IVBr) monotherapy and photodynamic therapy (PDT) as a second-line treatment in patients with polypoidal choroidal vasculopathy (PCV) who did not respond to first-line therapy.

METHODS

This case-control study included eyes with PCV that do not respond to aflibercept or ranibizumab. The patients were retrospectively registered. We compared outcomes, including best-corrected visual acuity (BCVA), anatomical results, and the need for additional treatments, between IVBr and a combination therapy using PDT as second-line treatments for refractory PCV, after adjusting for potential confounders. We analyzed E-values to evaluate the robustness of the results against unmeasured confounders.

RESULTS

Twenty-two eyes received IVBr, and twenty-four underwent PDT. No apparent differences were observed in BCVA and central macular thickness (CMT) changes from baseline between the groups (IVBr vs. PDT: BCVA, 0.01 ± 0.47 logMAR vs. 0.04 ± 0.18 logMAR, P-value = 0.756; CMT: - 36.3 ± 99.4 μm vs. - 114.7 ± 181.4 μm, P-value = 0.146). Only in the PDT group, five eyes (20.8%) did not require additional treatment after the second-line treatment, the adjusted odds ratio indicating no further treatment needed was 11.98 (95% confidence interval: 1.42-2070.07, P-value = 0.019). The E-value for the adjusted odds ratio was 23.44.

CONCLUSIONS

Both second-line treatments for PCV exhibited similar visual and anatomical outcomes. Only in the PDT-treated eyes were there some patients who did not require further treatment after second-line therapy.

Red Light-Triggered Anti-Angiogenic and Photodynamic Combination Therapy of Age-Related Macular Degeneration

Choroidal neovascularization (CNV) is the key pathological event of wet age-related macular degeneration (wAMD) leading to irreversible vision loss. Currently, anti-angiogenic therapy with anti-vascular endothelial growth factor (VEGF) agents has become the standard treatment for wAMD, while it is still subject to several limitations, including the safety concerns of monthly intravitreal administration and insufficient efficacy for neovascular occlusion. Combined therapy with photodynamic therapy (PDT) and anti-angiogenic agents has emerged as a novel treatment paradigm. Herein, a novel and less-invasive approach is reported to achieve anti-angiogenic and photodynamic combination therapy of wAMD by intravenous administration of a photoactivatable nanosystem (Di-DAS-VER NPs). The nanosystem is self-assembled by reactive oxygen species (ROS)-sensitive dasatinib (DAS) prodrug and photosensitizer verteporfin (VER). After red-light irradiation to the diseased eyes, intraocular release of anti-angiogenic DAS is observed, together with selective neo-vessels occlusion by VER-generated ROS. Notably, Di-DAS-VER NPs demonstrates promising therapeutic efficacy against CNV with minimized systemic toxicity. The study enables an efficient intravenous wAMD therapy by integrating a photoactivation process with combinational therapeutics into one simple nanosystem.

SUSTAINED BIWEEKLY AFLIBERCEPT FOR REFRACTORY NEOVASCULAR AGE-RELATED MACULAR DEGENERATION: The Prospective TRISTAR Study

PURPOSE

To assess the safety and efficacy of biweekly (every 2 weeks) intravitreal aflibercept injections (IAI) 2 mg in eyes with refractory neovascular age-related macular degeneration (NVAMD).

METHODS

A prospective, single-arm, interventional study was conducted. Eyes with refractory NVAMD received six biweekly IAIs through week 12, followed by a 4-week treatment pause until week 16. Eyes with residual subretinal fluid (SRF) at week 16 were randomized 1:1 to either four additional biweekly IAIs or to 4-week (q4W) IAI dosing through week 24. All eyes were subsequently treated q4W through week 52.

RESULTS

Enrolled eyes (n = 22) had persistent SRF despite a mean of 11.8 injections over the prior 12 months. One patient developed endophthalmitis at week 12. There were no additional drug/procedure-related adverse events. Best-corrected visual acuity (BCVA) improved significantly from baseline to week 14 (2.52 letters, P < 0.001). The mean central subfield thickness (CST) was also significantly improved at week 14 (-31.9 µ m, P < 0.001) with eight of 22 eyes achieving complete SRF resolution. Only two of eight eyes remained free of SRF at week 16, with a corresponding increase in mean CST of 26.7 µ m compared with week 14. By week 52, improvements in BCVA and CST were lost.

CONCLUSION

In patients with refractory NVAMD-related SRF, sustained biweekly IAIs resulted in significant functional and anatomical improvements during biweekly dosing. These gains, however, were lost on return to monthly dosing. These findings suggest that efforts to reduce refractory SRF in NVAMD with biweekly dosing may provide added benefit compared with standard of care treatment if biweekly dosing is sustained.

Rescue Photodynamic Therapy for Age-Related Macular Degeneration Refractory to Anti-Vascular Endothelial Growth Factor Monotherapy

BACKGROUND

To evaluate the 3-year outcome in eyes with neovascular age-related macular degeneration (nAMD) treated with intravitreal anti-vascular endothelial growth factor monotherapy or rescue therapy using standard verteporfin photodynamic therapy (PDT), and corroborate efficacy of rescue PDT.

METHODS

Patients were administered aflibercept injections once a month for 3 months followed by once every 2 months in the first year. After year 1, treatment with aflibercept monotherapy as indicated or in combination with PDT at the retinal specialist's discretion. Only cases completing the three-year follow-up were included. Regression analysis with visual acuity and macular atrophy at year 3 was performed for the dependent variable.

RESULTS

Of the 292 eyes, 15 eyes underwent rescue PDT following year 1. The best-corrected visual acuity (logarithm of minimal angle of resolution, mean/Snellen equivalent ± SD) was 0.35 (20/45) ± 0.38, 0.23 (20/30) ± 0.36, 0.26 (20/35) ± 0.38, and 0.31 (20/40) ± 0.42 at baseline, year 1, year 2, and year 3, respectively. Multiple regression analysis revealed that the rescue PDT was significantly associated with macular atrophy and poor visual outcome at year 3 (odds ratio = 1.2, p < 0.001; β = 0.23, p = 0.0029, respectively).

CONCLUSIONS

The visual outcome in eyes with nAMD retained baseline levels at year 3; however, patients treated with rescue PDT developed macular atrophy more frequently and poor visual outcomes.

One-year efficacy of "rescue photodynamic therapy" for patients with typical age-related macular degeneration, polypoidal choroidal vasculopathy, and pachychoroid neovasculopathy refractory to anti-vascular endothelial growth factor therapy

PURPOSE

This study aimed to evaluate the one-year outcomes of photodynamic therapy (PDT) as a rescue treatment for age-related macular degeneration (AMD) refractory to anti-vascular endothelial growth factor (VEGF) therapy.

METHODS

Patients with AMD refractory to anti-VEGF therapy, treated with "rescue-PDT" were retrospectively investigated. The time of PDT was defined as the baseline value. Baseline characteristics including sex, age, best-corrected visual acuity (BCVA), central macular thickness (CMT), and foveal choroidal thickness (FCT) were examined. The changes in BCVA, CMT, and recurrence were also assessed at the 1-year follow-up. The logMAR VA change of 0.3 or more was defined as "improved" or "declined."

RESULTS

Twenty-three consecutive eyes (typical AMD: 10 eyes, polypoidal choroidal vasculopathy: 10 eyes, and pachychoroid neovasculopathy: 3 eyes), which underwent "rescue-PDT," were analyzed in this study. The BCVA was improved in three patients and maintained in 20 patients at 12 months after PDT (mean BCVA change: 0.11 ± 0.19). The CMT improved in 19 patients (82.6%), and the mean CMT changed from 318.5 ± 93.7 μm to 225.9 ± 51.6 μm (p < 0.01) 12 months after PDT. "Retreatment" of anti-VEGF drug injections was considered if the retinal fluid or retinal hemorrhage recurred after PDT. The baseline FCT of the "retreatment group (15 eyes)" was significantly lower than that of the "no retreatment group (8 eyes)" (206.3 ± 50.7 μm vs 293.9 ± 85.7 μm: p = 0.033).

CONCLUSIONS

PDT could be an effective treatment option for anti-VEGF refractory AMD to maintain visual acuity and control retinal fluid for up to 12 months.

Dexamethasone implant improves anatomic response to anti-VEGF therapy in treatment-resistant polypoidal choroidal vasculopathy

BACKGROUND

A significant proportion of eyes with polypoidal choroidal vasculopathy (PCV) can be resistant to anti-vascular endothelial growth factor (VEGF) injections. We evaluated the efficacy of a combination of dexamethasone intravitreal implant (DXI) and anti-VEGF therapy in eyes resistant to anti-VEGF monotherapy.

METHODS

In this retrospective study, patients with PCV resistant to anti-VEGF injections were additionally injected with a DXI along with an anti-VEGF agent. Best-corrected visual acuity (BCVA), slit-lamp examination, fundus evaluation, and optical coherence tomography (OCT) data were analyzed. Anatomical response on OCT was the primary outcome measure. Change in visual acuity and injection-free interval after DXI were evaluated as secondary outcome measures.

RESULTS

Twelve eyes of 11 patients were included in the study. Mean age of patients at presentation was 64.7 ± 9.5 years (range, 49-78.8 years), and there were seven females (63.6%). Median number of anti-VEGF injections prior to DXI was 4 (interquartile range IQR, 3-7). Median follow-up duration after DXI was 32.2 months (IQR, 6.6-41.6 months). Median logMAR BCVA immediately prior to DXI was 0.41 (IQR, 0.30-0.88) and after injection was 0.40 (IQR, 0.30-1.05), which was not significantly different (p = 0.85). Median Central Retinal Thickness (CRT) after DXI was 305.5 µm (IQR, 249-409 µm), which was significantly (p = 0.003) lesser than pre-injection thickness of 547 µm (IQR, 431-771 µm). Median injection-free interval in these eyes after DXI was 5 months (IQR, 2.8-6.4 months). Kaplan-Meier estimates of first injection after DXI were 27.3% at 3 months, 67.3% at 6 months, and 89.1% at 12 months.

CONCLUSIONS

Dexamethasone implant combined with anti-VEGF treatment can prolong the treatment-free interval in eyes with PCV resistant to anti-VEGF injection while maintaining visual acuity.

Targeting senescent retinal pigment epithelial cells facilitates retinal regeneration in mouse models of age-related macular degeneration

Although age-related macular degeneration (AMD) is a multifactorial disorder with angiogenic, immune, and inflammatory components, the most common clinical treatment strategies are antiangiogenic therapies. However, these strategies are only applicable to neovascular AMD, which accounts for less than 20% of all AMD cases, and there are no FDA-approved drugs for the treatment of dry AMD, which accounts for ~ 80% of AMD cases. Here, we report that the elimination of senescent cells is a potential novel therapeutic approach for the treatment of all types of AMD. We identified senescent retinal pigment epithelium (RPE) cells in animal models of AMD and determined their contributions to retinal degeneration. We further confirmed that the clearance of senescent RPE cells with the MDM2-p53 inhibitor Nutlin-3a ameliorated retinal degeneration. These findings provide new insights into the use of senescent cells as a therapeutic target for the treatment of AMD.

Long-term results of rescue photodynamic therapy for type 1 neovascularization refractory to anti-vascular endothelial growth factor

PURPOSE

To evaluate long-term results of photodynamic therapy (PDT) as a rescue treatment in patients with type 1 neovascularization refractory to intravitreal anti-vascular endothelial growth factor (VEGF).

METHODS

Patients who underwent reduced-fluence PDT for refractory type 1 neovascularization, which showed persistent subretinal and/or intraretinal fluid after three or more consecutive anti-VEGF treatments, and were followed up for ≥24 months were reviewed.

RESULTS

Seventy-eight eyes of 78 patients were included, and 37 (47%) were classified as polypoidal choroidal vasculopathy (PCV). The mean number of anti-VEGF injections before rescue PDT was 8.5 ± 5.4, and the mean follow-up period after rescue PDT was 74.0 ± 29.4 months. At 3 months after rescue PDT, exudation completely resolved in 55 (71%) patients and vision significantly improved (p = 0.021). Resolution of exudation was associated with choroidal vascular hyperpermeability [odds ratio (OR), 3.82; p = 0.031] and lower maximal height of pigment epithelial detachment (OR, 0.69; p = 0.018). In these patients, exudation recurred in 49 (89%) after mean period of 13.5 months. Vision significantly worsened at 24 months after rescue PDT, and thereafter, and the vision decrease was more prominent in patients with PCV. Rescue PDT could be repeated for recurrent or persistent exudation without increasing the risk of complications.

CONCLUSION

In patients with type 1 neovascularization refractory to anti-VEGF, reduced-fluence PDT is an effective and safe rescue treatment. Therapeutic efficacy wore off during long-term follow-up, but rescue PDT may be repeated safely.

Long-term outcomes of polypoidal choroidal vasculopathy in comparison with typical exudative age-related macular degeneration

PURPOSE

To compare long-term outcomes between typical exudative age-related macular degeneration (TexAMD) and polypoidal choroidal vasculopathy (PCV), and to investigate factors related to the outcomes.

METHODS

This retrospective study included 319 eyes (164 with TexAMD and 155 with PCV) treated with anti-vascular endothelial growth factor and followed more than 5 years. The primary outcome was visual acuity (VA) change from baseline to final visit. Linear regression analyses were used to determine factors associated with final VA.

RESULTS

Baseline logMAR VA was 0.7 ± 0.5 in the TexAMD group and 0.5 ± 0.4 in the PCV group (p < 0.001). After a mean follow-up of 9 years, final VA was also significantly worse in the TexAMD group than in the PCV group (0.9 ± 0.6 vs. 0.6 ± 0.5; p < 0.001). The PCV group showed longer maintenance of improved vision and later onset of significant visual decline than the TexAMD group. In multivariate analysis, loss to follow-up, worse baseline VA, macular atrophy, and subretinal fibrosis were significantly associated with poor final VA in both groups.

CONCLUSION

PCV eyes showed relatively favorable long-term visual outcome than TexAMD eyes. The results of this study emphasized the importance of compliance with treatment, along with other well-known prognostic factors.

Automated segmentation of choroidal layers from 3-dimensional macular optical coherence tomography scans

BACKGROUND

Changes in choroidal thickness are associated with various ocular diseases, and the choroid can be imaged using spectral-domain optical coherence tomography (SD-OCT) and enhanced depth imaging OCT (EDI-OCT).

NEW METHOD

Eighty macular SD-OCT volumes from 80 patients were obtained using the Zeiss Cirrus machine. Eleven additional control subjects had two Cirrus scans done in one visit along with enhanced depth imaging (EDI-OCT) using the Heidelberg Spectralis machine. To automatically segment choroidal layers from the OCT volumes, our graph-theoretic approach was utilized. The segmentation results were compared with reference standards from two independent graders, and the accuracy of automated segmentation was calculated using unsigned/signed border positioning/thickness errors and Dice similarity coefficient (DSC). The repeatability and reproducibility of our choroidal thicknesses were determined by intraclass correlation coefficient (ICC), coefficient of variation (CV), and repeatability coefficient (RC).

RESULTS

The mean unsigned/signed border positioning errors for the choroidal inner and outer surfaces are 3.39 ± 1.26 µm (mean ± standard deviation)/- 1.52 ± 1.63 µm and 16.09 ± 6.21 µm/4.73 ± 9.53 µm, respectively. The mean unsigned/signed choroidal thickness errors are 16.54 ± 6.47 µm/6.25 ± 9.91 µm, and the mean DSC is 0.949 ± 0.025. The ICC (95% confidence interval), CV, RC values are 0.991 (0.977-0.997), 2.48%, 14.25 µm for the repeatability and 0.991 (0.977-0.997), 2.49%, 14.30 µm for the reproducibility studies, respectively.

COMPARISON WITH EXISTING METHOD(S)

The proposed method outperformed our previous method using choroidal vessel segmentation and inter-grader variability.

CONCLUSIONS

This automated segmentation method can reliably measure choroidal thickness using different OCT platforms.

Anti-VEGF-Resistant Retinal Diseases: A Review of the Latest Treatment Options

Anti-vascular endothelial growth factor (anti-VEGF) therapy currently plays a central role in the treatment of numerous retinal diseases, most notably exudative age-related macular degeneration (eAMD), diabetic retinopathy and retinal vein occlusions. While offering significant functional and anatomic benefits in most patients, there exists a subset of 15–40% of eyes that fail to respond or only partially respond. For these cases, various treatment options have been explored with a range of outcomes. These options include steroid injections, laser treatment (both thermal therapy for retinal vascular diseases and photodynamic therapy for eAMD), abbreviated anti-VEGF treatment intervals, switching anti-VEGF agents and topical medications. In this article, we review the effectiveness of these treatment options along with a discussion of the current research into future directions for anti-VEGF-resistant eyes.

Aflibercept therapy for exudative age-related macular degeneration resistant to bevacizumab and ranibizumab

Background

Despite the good outcomes achieved with intravitreal angiogenic therapy, a subset of neovascular age-related macular degeneration (AMD) patients experience resistance to therapy after repeated injections. Switching drugs could offer benefit to this group of patients.

Purpose

To determine visual and anatomical outcomes in a cohort of neovascular AMD patients resistant to repeated injections of bevacizumab/ranibizumab after switching to aflibercept therapy.

Methods

This was a retrospective chart review of patients who had a diagnosis of neovascular AMD and persistent intraretinal (IRF) and/or subretinal fluid (SRF) on optical coherence tomography (OCT) for at least 3 months despite monthly bevacizumab and/or ranibizumab injections prior to transition to aflibercept. We reviewed patients’ records and OCT images obtained at baseline, 1, 3, 6 and 12 months after transition to aflibercept. Data collected included demographics, best-corrected visual acuity (BCVA), number of injections received and the occurrence of any adverse events. Studied OCT parameters included central macular thickness (CMT) values and the presence or absence of SRF, IRF and/or pigment epithelial detachment (PED) at each visit.

Results

We included 53 eyes of 48 patients. Mean change in BCVA from baseline was 0.05 ± 0.13 (P = 0.01) at M1, 0.04 ± 0.16 (P = 0.08) at M3, 0.01 ± 0.22 (P = 0.9) at M6, and 0.02 ± 0.28 (P = 1) at M12, while the mean change in CMT from baseline was 64 ± 75 μm (P < 0.0001) at M1, 42 ± 85 μm (P = 0.002) at M3, 47 ± 69 μm (P < 0.0001) at M6, and 46 ± 99 μm (P = 0.001) at M12. The percentage of eyes with SRF decreased from 77.4% at baseline to 39.6% at M1, then increased to 47.2% at M3, then decreased to 43.4% at M6, and to 41.5% at M12 (All p < 0.001, compared to baseline). Compared to baseline, there was a statistically significant decrease in the percentage of eyes having IRF from 47.2 to 20.8% at M1 (p < 0.001), 30.2% at M3, 24.5% at M6 and 26.4% at M12 (p < 0.01, each). The number of bevacizumab and/or ranibizumab injections (7.36 ± 1.85) was significantly higher than that of aflibercept (6.47 ± 2.45, p = 0.001). A significant direct relationship between CMT reduction and BCVA improvement was demonstrated at M1 (p = 0.01, r = 0.36), M3 (p = 0.03, r = 0.30) and M12 (p = 0.03, r = 0.30). Eyes with IRF had significantly poorer BCVA than eyes without IRF at baseline (p = 0.02) and M3 (p = 0.04).

Conclusion

Switching to intravitreal aflibercept therapy in a cohort of neovascular AMD patients resistant to chronic bevacizumab and/or ranibizumab injections can lead to significant visual improvement in the short term and sustained reduction of central macular thickness over 1 year of followup.

Cell-Matrix Interactions in the Eye: From Cornea to Choroid

The extracellular matrix (ECM) plays a crucial role in all parts of the eye, from maintaining clarity and hydration of the cornea and vitreous to regulating angiogenesis, intraocular pressure maintenance, and vascular signaling. This review focuses on the interactions of the ECM for homeostasis of normal physiologic functions of the cornea, vitreous, retina, retinal pigment epithelium, Bruch's membrane, and choroid as well as trabecular meshwork, optic nerve, conjunctiva and tenon's layer as it relates to glaucoma. A variety of pathways and key factors related to ECM in the eye are discussed, including but not limited to those related to transforming growth factor-β, vascular endothelial growth factor, basic-fibroblastic growth factor, connective tissue growth factor, matrix metalloproteinases (including MMP-2 and MMP-9, and MMP-14), collagen IV, fibronectin, elastin, canonical signaling, integrins, and endothelial morphogenesis consistent of cellular activation-tubulogenesis and cellular differentiation-stabilization. Alterations contributing to disease states such as wound healing, diabetes-related complications, Fuchs endothelial corneal dystrophy, angiogenesis, fibrosis, age-related macular degeneration, retinal detachment, and posteriorly inserted vitreous base are also reviewed.

Genetic Association between MMP9 and Choroidal Neovascularization in Age-Related Macular Degeneration

Purpose

To evaluate the first association specific to exudative age-related macular degeneration (AMD) located near the matrix metalloproteinase 9 (MMP9) gene.

Design

Genetic association study.

Participants

One thousand seven hundred twelve patients with AMD (672 nonexudative, 1040 exudative) of predominantly northern European descent seeking treatment at the University of Iowa Hospitals and Clinics.

Methods

We reanalyzed the International AMD Genetics Consortium (IAMDGC) data to validate the association of polymorphisms near MMP9 with exudative AMD and to identify additional associated single nucleotide polymorphisms (SNPs), especially MMP9 coding sequence SNPs. We genotyped a cohort of 1712 AMD patients from Iowa with 3 SNPs identified with our analysis of the IAMDGC cohort using commercially available real-time quantitative polymerase chain reaction (PCR) assays. Firth regression was used to measure the association between MMP9 SNP genotypes and exudative AMD in our cohort of patients from Iowa. In addition, we developed a PCR-based assay to genotype the Iowa cohort at a short tandem repeat polymorphism (STRP) at the MMP9 locus.

Main Outcome Measures

Odds ratios and P values for exudative compared with nonexudative AMD patients in the Iowa cohort for MMP9 SNPs (rs4810482, rs17576, and rs17577) and STRP.

Results

We identified 3 SNPs in the MMP9 locus (rs4810482, rs17576, and rs17577) that are highly associated with exudative AMD in patient cohorts of the IAMDGC. These MMP9 SNPs also are associated with exudative AMD in the cohort of 1712 AMD patients from Iowa (rs4810482: odds ratio [OR], 0.82; P = 0.010; rs17576: OR, 0.86; P = 0.046; and rs17577: OR, 0.80; P = 0.041). We also genotyped the cohort of AMD patients from Iowa at rs142450006, another MMP9 polymorphism that previously was associated with exudative AMD. We detected a 4bp STRP, (TTTC)n, at the rs142450006 locus that is highly polymorphic and associated significantly with exudative AMD (OR, 0.78; P = 0.016).

Conclusions

This study independently confirms and expands an association between the MMP9 locus and exudative AMD, further implicating a role for extracellular matrix abnormalities in choroidal neovascularization.

Comparison of the effects of anti-vascular endothelial growth factor treatments on pigment epithelial detachment in age-related macular degeneration

PURPOSE

The aim of this study is to compare structural and visual outcomes of naive neovascular age-related macular degeneration patients with significant pigment epithelial detachment (PED), treated with ranibizumab and aflibercept.

METHODS

This was a retrospective case series that included 33 naive patients treated with ranibizumab and 25 with aflibercept. The patients were followed with pro re nata (PRN) after first three intravitreal injections. LogMAR visual acuity, PED height and radius on spectral domain optical coherence tomography findings were compared.

RESULTS

Baseline mean PED height was 270.39 ± 114.14 µm and 315.24 ± 115.8 µm (p = 0.14); baseline mean PED radius was 2063.64 ± 942.75 µm and 1958.88 ± 452.22 µm (p = 0.61); and baseline BCVA was 1.16 ± 0.73 and 1.09 ± 0.69 (p = 0.73), for ranibizumab, and aflibercept group, respectively. In aflibercept group, there was statistically significant decrease in PED height at first, third and 12th months. In PED radius, decrease was greater in aflibercept group, however not significant. In addition, in aflibercept group visual acuity was better at all three months; however, none of them were significant.

CONCLUSION

Although the maximum improvement was seen at third month, final visual acuity and parameters of PED were better in aflibercept group. The efficacy of the both drug to choroidal neovascularization was known; however, in cases with significant PED, aflibercept can be consider for the first-level treatment.

Time course of swept-source optical coherence tomography angiography findings after photodynamic therapy and aflibercept in eyes with age-related macular degeneration

Purpose

To report swept-source optical coherence tomography angiography (SS-OCTA) findings after full-fluence photodynamic therapy (PDT) and aflibercept intravitreal injection (IVA) for age-related macular degeneration (AMD).

Methods

Five eyes of five patients with AMD treated with PDT and IVA were include into the study. We retrospectively reviewed the data obtained from the five patients using SS-OCTA before and after treatment. Three eyes had type 1 choroidal neovascularization (CNV) and two eyes had polypoidal choroidal vasculopathy.

Results

Before treatment, the CNV signals detected in all cases, decreased in three eyes and were not detected completely in two eyes at 1 months after treatment. The areas indicating CNV increased over time, but they did not increase to the baseline level. No CNV signal was detected in one eye during follow-up. In all cases, the exudation unchanged or resolved without additional IVA; the exudation recurred in two cases. In one eye, the CNV signal and the exudation occurred simultaneously; however, there was no association in another eye. A feeder vessel, from which the CNV signal seemed to originate, was seen in one of the five eyes.

Conclusion and Importance

SS-OCTA is useful to monitor the morphology of CNV after PDT and IVA, indicating that the remodeling of the choroidal vasculature occurs gradually after treatment. The presence or absence of the CNV signal might indicate CNV activity.

Choriocapillaris Degeneration in Geographic Atrophy

Early age-related macular degeneration (AMD) is characterized by degeneration of the choriocapillaris, the vascular supply of retinal photoreceptor cells. We assessed vascular loss during disease progression in the choriocapillaris and larger vessels in the deeper choroid. Human donor maculae from controls (n = 99), early AMD (n = 35), or clinically diagnosed with geographic atrophy (GA; n = 9, collected from outside the zone of retinal pigment epithelium degeneration) were evaluated using Ulex europaeus agglutinin-I labeling to discriminate between vessels with intact endothelial cells and ghost vessels. Morphometric analyses of choriocapillaris density (cross-sectional area of capillary lumens divided by length) and of vascular lumen/stroma ratio in the outer choroid were performed. Choriocapillaris loss was observed in early AMD (Bonferroni-corrected P = 0.024) with greater loss in GA (Bonferroni-corrected P < 10^-9), even in areas of intact retinal pigment epithelium. In contrast, changes in lumen/stroma ratio in the outer choroid were not found to differ between controls and AMD or GA eyes (P > 0.05), suggesting choriocapillaris changes are more prevalent in AMD than those in the outer choroid. In addition, vascular endothelial growth factor-A levels were negatively correlated with choriocapillaris vascular density. These findings support the concept that choroidal vascular degeneration, predominantly in the microvasculature, contributes to dry AMD progression. Addressing capillary loss in AMD remains an important translational target.

Bevacizumab dosing every 2 weeks for neovascular age-related macular degeneration refractory to monthly dosing

PURPOSE

To evaluate intravitreal bevacizumab every 2 weeks (biweekly) in refractory neovascular age-related macular degeneration (nAMD).

STUDY DESIGN

Retrospective study.

METHODS

A retrospective study of consecutive nAMD patients unresponsive to monthly intravitreal anti-vascular endothelial growth factor (VEGF) switched to 3-4 biweekly injections.

RESULTS

Twenty-seven eyes of patients aged 82.08  ± 6.85 years were included. Prior to the 2-week interval bevacizumab injections, 74.1% (n=20) were treated with both bevacizumab and ranibizumab, 11.1% (3 eyes) also received aflibercept and 14.8% (4 eyes) had received prior treatment of monthly bevacizumab (average number of injections 21.5 ± 6.7). Best corrected visual acuity (BCVA) remained stable between baseline (logMAR 0.72± 0.60) and follow-up (0.76± 0.66) (p=0.41). Mean central macular thickness and macular volume did not change significantly between baseline and follow-up (p=0.35 and p=0.60, respectively). Six eyes (22.2%) showed morphologic anatomic improvements, while 19 eyes (70.4%) were stable and two eyes (7.4%) deteriorated from baseline. Subretinal fluid completely resolved in 3 of the eyes and improved in the other 3 eyes and in this group (22.2%) both central macular thickness (326.2 ± 101.4 versus 297.5 ± 97.2, p=0.002) and macular volume (8.69 ± 1.69 versus 8.22 ± 1.43, p=0.03) were significantly reduced. No adverse events were observed in any of the treated eyes.

CONCLUSION

This study demonstrates that biweekly bevacizumab injections are effective in nearly one-quarter of nAMD non-responders with no adverse events reported. Switching earlier, rather than later, to this low cost modality may be of benefit for a portion of non-responders to conventional treatment.

Real-world use of ranibizumab for neovascular age-related macular degeneration in Taiwan

This study investigated the “real-world” use of ranibizumab for neovascular age-related macular degeneration (nAMD) in Taiwan and assessed the visual outcome. We reviewed the medical records at National Cheng Kung University Hospital, Taiwan, during 2012–2014 for 264 consecutive eyes of 229 patients with nAMD, who applied for ranibizumab covered by national health insurance. A total of 194 eyes (73.5%) in 179 patients (65.5% men; mean ± standard deviation age 69.4 ± 10.7 years) were pre-approved for treatment. Applications for treatment increased year by year, but approval rates decreased during this time. The major causes of rejection for funding were diseases mimicking nAMD, including macular pucker/epiretinal membrane, macular scarring, dry-type AMD, and possible polypoidal choroidal vasculopathy. After completion of three injections in 147 eyes, visual acuity significantly improved, gaining ≥1 line in 51.8% of eyes and stabilising in 38.3% of 141 eyes in which visual acuity was measured. The 114 eyes approved with only one application had a better visual outcome than the 27 eyes approved after the second or third applications. In conclusion, ranibizumab is effective for nAMD; however, approval after the second or third application for national health insurance cover is a less favourable predictor of visual outcome.

Management of Choroidal Neovascular Membranes Associated with Choroidal Nevi

PURPOSE

To evaluate the management options for choroidal neovascular membrane (CNVM) associated with choroidal nevus.

DESIGN

Cohort study.

PARTICIPANTS

Twenty-four eyes with CNVM associated with choroidal nevus.

METHODS

Retrospective review of demographic and clinical features and management and outcome of eyes with CNVM associated with choroidal nevus.

MAIN OUTCOME MEASURES

Choroidal neovascular membrane status, subfoveal retinal thickness, and visual outcome.

RESULTS

Choroidal neovascular membrane was classic in 20 eyes (83%) and occult in 4 eyes (27%). Of 15 eyes (63%) treated with intravitreal bevacizumab injections, complete regression of CNVM was observed in 6 eyes (40%) and partial regression was achieved in 5 eyes (33%). Visual acuity improved or remained stable in these eyes, and the mean subfoveal retinal thickness decreased significantly from 477 μm to 326 μm. Four eyes (27%) with unresponsive, active CNVM were treated with combined photodynamic therapy (PDT) and bevacizumab therapy; complete or partial regression was observed in 3 eyes with improved or stable visual acuity, and the mean subfoveal retinal thickness decreased from 441 μm to 350 μm. Of 5 eyes (33%) treated with PDT, 4 (80%) showed partial regression. Visual acuity remained stable in these eyes and the mean subfoveal retinal thickness decreased from 370 μm to 334 μm. In 4 eyes with non-vision-threatening CNVM (17%), complete or partial regression was seen in 2 eyes, and CNVM remained active in 2 eyes after observation. Visual acuity remained stable. No significant difference was found between the mean subfoveal retinal thickness at presentation and at the last visit. All choroidal nevi remained stable in thickness and size after a mean follow-up of 30 months.

CONCLUSIONS

Intravitreal bevacizumab injection was effective in achieving complete or partial regression of CNVM in 73% of eyes with improved visual acuity and decreased subfoveal retinal thickness. Combined PDT and bevacizumab therapy led to further regression in eyes that had failed treatment with bevacizumab previously. Some cases of choroidal neovascularization associated with choroidal nevi did not seem to threaten the vision.

Development of Multigenic Lentiviral Vectors for Cell-Specific Expression of Antiangiogenic miRNAs and Protein Factors

Generation of lentivirus (LV)-based vectors holding multiple gene cassettes for coexpression of several therapeutic factors provides potent tools in both gene delivery studies as well as in gene therapy. Here we describe the development of such multigenic LV gene delivery vectors enabling cell-specific coexpression of antiangiogenic microRNA (miRNA) and protein factors and, if preferred, a fluorescent reporter, from RNApol(II)-driven expression cassettes orientated in a back-to-back fashion. This configuration may contribute to the development of new combination therapies for amelioration of diseases involving intraocular neovascularization including exudative age-related macular degeneration (AMD).

Age-related macular degeneration: is polypoidal choroidal vasculopathy recognized and treated?

OBJECTIVE

To assess how polypoidal choroidal vasculopathy (PCV) is recognized and treated, and to assess whether treatment outcomes are different between Chinese and Caucasian Canadian patients with age-related macular degeneration (AMD).

DESIGN

Retrospective chart review.

PARTICIPANTS

154 eyes from 135 Chinese patients and 2291 eyes from 1792 Caucasian patients who were newly diagnosed with either AMD or PCV and had more than 1 year of follow-up were included.

METHODS

All newly diagnosed AMD patients presenting to the Retina Service of 3 Toronto University Hospitals, between March 25, 2008, to September 30, 2014, were reviewed.

RESULTS

10/154 eyes (6.5%) in Chinese Canadians and 16/2291 eyes (0.7%) in Caucasian Canadians were diagnosed as having PCV. Indocyanine green angiography (ICGA) was used to diagnose PCV in 20% of Chinese Canadians and 8.8% of Caucasian Canadians. Clinical practices with a larger percentage of Chinese patients were more likely to diagnose PCV in both Chinese (p = 0.004) and Caucasian patients (p = 0.03), were more likely to use photodynamic therapy (PDT) (p < 0.01), and had significantly greater central retinal thickness decrease (p < 0.001).

CONCLUSION

Our study has shown that PCV is under-recognized in a Canadian population, and ICGA is underutilized. In clinical practices with a greater portion of Chinese patients, PCV is more often recognized and PDT is used more liberally.

ROLE OF ADDITIONAL DEXAMETHASONE FOR THE MANAGEMENT OF PERSISTENT OR RECURRENT NEOVASCULAR AGE-RELATED MACULAR DEGENERATION UNDER RANIBIZUMAB TREATMENT

PURPOSE

To assess the efficacy of a combination therapy of intravitreal ranibizumab together with a dexamethasone implant in comparison with ranibizumab monotherapy in neovascular age-related macular degeneration.

METHODS

Forty eyes of recurrent or persistent neovascular age-related macular degeneration were included in this prospective study. Patients were randomly assigned to two groups. Based on a pro re nata treatment regimen, the first group received intravitreal ranibizumab monotherapy (IVM). The second group received a combination of intravitreal dexamethasone implant and ranibizumab (intravitreal combination [IVC]) at baseline and was retreated with ranibizumab as needed. A second dexamethasone implant was allowed for retreatment after at least 6 months. Retreatment criteria included evidence of subretinal fluid, cystoid macular edema or new hemorrhage, and/or a visual acuity decrease of 5 Early Treatment Diabetic Retinopathy Study letters.

RESULTS

During 12 months, a mean of 7.95/5.5 (IVM/IVC; P = 0.042) retreatments were given. The median time until first retreatment differed significantly between the groups (P = 0.004). Functional variables could be maintained in both groups with no differences between them. Visual acuity changed from 62 letters at baseline to 67 at Month 12 in the IVM and remained stable at 68 letters in the IVC group (P = 0.68); macular sensitivity changed from 6.95 dB to 7.01 dB in IVM and from 7.24 dB to 7.12 dB in IVC (P = 0.4). Central retinal thickness decreased, however, with no difference between the groups (P = 0.38). In the IVM/IVC group, 11/12 (55/60%) patients were phakic at the time of study entry. One (9%) patient from the IVM and 4 (33%) from the IVC group were referred to cataract surgery after study completion (P = 0.4).

CONCLUSION

This pilot study indicates combined therapy to delay retreatment in patients with persistent/recurrent neovascular age-related macular degeneration and an overall reduction in required ranibizumab retreatments compared with ranibizumab monotherapy with consistent functional outcomes.

The Impact of Switching Anti-Vascular Endothelial Growth Factor Therapy in the Management of Exudative Age-Related Macular Degeneration

Switching of anti-vascular endothelial growth factor (VEGF) therapy in the management of poorly responsive exudative age-related macular degeneration (AMD) has had suggested benefits in individual reports that have yet to be consolidated. In this retrospective review, 24 studies published between 2009 and 2014 were identified. Reasons for switching included tachyphylaxis, health insurance coverage, cost issues, and nonresponse or inadequate response. Nine studies had data that could be used for comparison between studies. Median follow-up was 10.6 months (range: 4.2 months to 21.8 months). Mean baseline visual acuity (VA) ranged from 0.42 logMar to 0.94 logMar (standard deviation [SD] range: 0.05 logMar to 0.50 logMar) and mean VA on final follow-up ranged from 0.38 logMar to 0.78 logMar (SD range: 0.08 logMar to 0.50 logMar). Five of nine studies reported no statistically significant change in vision, and five of nine studies reported a statistically significant improvement in central retinal thickness. This review found that switching anti-VEGF did not confer significant improvement of VA, although it provided some anatomical improvement. Pertinent considerations for evaluating response following anti-VEGF therapy are also presented in this review. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:859-869.].

Photodynamic Therapy for Pseudophakic Eyes Compared to Eyes With Cataract

BACKGROUND AND OBJECTIVE

Verteporfin photodynamic therapy (vPDT) plays a role in the treatment of chorioretinal conditions. The purpose of this study was to compare vPDT outcomes between cataractous and pseudophakic eyes.

PATIENTS AND METHODS

In this prospective study of consecutive patients with choroidal neovascularization (CNV) secondary to neovascular age-related macular degeneration (nAMD) treated with vPDT, cataract and pseudophakic eyes were compared for number and timing of vPDT treatments, duration of follow-up, angiographic features, and changes in best-corrected visual acuity (BCVA).

RESULTS

Overall, 103 eyes (n = 95) were included in the final analysis; 44 eyes in the cataract group and 59 eyes in the pseudophakic group. No significant difference in change in BCVA (P = .19) or leakage-free CNV lesions (P = .58) was found between the groups.

CONCLUSIONS

In this study of vPDT for nAMD, there was no significant difference between eyes with cataract and pseudophakic eyes. It seems that cataract does not clinically alter the effect of vPDT. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:1132-1136.].

Resistance to anti-VEGF therapy in neovascular age-related macular degeneration: a comprehensive review

As a progressive chronic disease, age-related macular degeneration (AMD) is the leading cause of irreversible vision impairment worldwide. Experimental and clinical evidence has demonstrated that vascular endothelial growth factor (VEGF) plays a vital role in the formation of choroidal neovascularization. Intravitreal injections of anti-VEGF agents have been recommended as a first-line treatment for neovascular AMD. However, persistent fluid or recurrent exudation still occurs despite standardized anti-VEGF therapy. Patients suffering from refractory or recurrent neovascular AMD may develop mechanisms of resistance to anti-VEGF therapy, which results in a diminished therapeutic effect. Until now, there has been no consensus on the definitions of refractory neovascular AMD and recurrent neovascular AMD. This article aims at clarifying these concepts to evaluate the efficacy of switching drugs, which contributes to making clinical decision more scientifically. Furthermore, insight into the causes of resistance to anti-VEGF therapy would be helpful for developing possible therapeutic approaches, such as combination therapy and multi-target treatment that can overcome this resistance.

Subretinal AAV2.COMP-Ang1 suppresses choroidal neovascularization and vascular endothelial growth factor in a murine model of age-related macular degeneration

To assess whether Tie2-mediated vascular stabilization ameliorates neovascular age-related macular degeneration (AMD), we investigated the impact of adeno-associated virus-mediated gene therapy with cartilage oligomeric matrix protein angiopoietin-1 (AAV2.COMP-Ang1) on choroidal neovascularization (CNV), vascular endothelial growth factor (VEGF), and hypoxia-inducible factor (HIF) in a mouse model of the disease. We treated mice with subretinal injections of AAV2.COMP-Ang1 or control (AAV2.AcGFP, AAV2.LacZ, and phosphate-buffered saline). Subretinal AAV2 localization and plasmid protein expression was verified in the retinal pigment epithelium (RPE)/choroid of mice treated with all AAV2 constructs. Laser-assisted simulation of neovascular AMD was performed and followed by quantification of HIF, VEGF, and CNV in each experimental group. We found that AAV2.COMP-Ang1 was associated with a significant reduction in VEGF levels (29-33%, p < 0.01) and CNV volume (60-70%, p < 0.01), without a concomitant decrease in HIF1-α, compared to all controls. We concluded that a) AAV2 is a viable vector for delivering COMP-Ang1 to subretinal tissues, b) subretinal COMP-Ang1 holds promise as a prospective treatment for neovascular AMD, and c) although VEGF suppression in the RPE/choroid may be one mechanism by which AAV2.COMP-Ang1 reduces CNV, this therapeutic effect may be hypoxia-independent. Taken together, these findings suggest that AAV2.COMP-Ang1 has potential to serve as an alternative or complementary option to anti-VEGF agents for the long-term amelioration of neovascular AMD.

Photodynamic therapy: current role in the treatment of chorioretinal conditions

Verteporfin photodynamic therapy (vPDT) is a selective vaso-occlusive treatment that targets choroidal vascular abnormalities. It was initially developed to treat neovascular age-related macular degeneration using the 'standard' vPDT protocol (verteporfin 6 mg/m(2), vPDT laser fluence 50 J/cm(2)). vPDT therapy has subsequently evolved as an important treatment modality for a range of other chorioretinal conditions including choroidal haemangioma, central serous chorioretinopathy, polypoidal choroidal vasculopathy, and peripapillary choroidal neovascularisation. Various 'safety-enhanced' vPDT protocols have been devised to optimise treatment outcomes, typically using reduced dose verteporfin (verteporfin 3 mg/m(2)) or reduced fluence vPDT (vPDT laser fluence 25 J/cm(2)). This paper reviews the current role of vPDT therapy in the treatment of chorioretinal conditions.

REFRACTORY INTRARETINAL OR SUBRETINAL FLUID IN NEOVASCULAR AGE-RELATED MACULAR DEGENERATION TREATED WITH INTRAVITREAL RANIZUBIMAB: Functional and Structural Outcome

PURPOSE

To investigate the visual acuity results of eyes with neovascular age-related macular degeneration and refractory fluid despite monthly treatment with ranibizumab, and to investigate differences between refractory subretinal fluid and intraretinal cystic changes.

METHODS

Retrospective chart review of consecutive treatment-refractory neovascular age-related macular degeneration, defined as persistent intraretinal or subretinal fluid despite monthly ranibizumab injections during 12 months or more. Data were evaluated for baseline characteristics, type and location of the refractory fluid, mean visual acuity change, number of injections, and the time point of first complete disappearance of all fluid on spectral domain optical coherence tomography.

RESULTS

Seventy-six eyes (74 patients, mean age, 76.8 years) were identified. The mean follow-up was 33.6 months (range, 12-73 months). The mean number of injections was 11.4 in the first year and 27.7 over follow-up. The refractory fluid was located subfoveally in 61.8%. In 27 eyes (35.5%), the fluid resolved after a mean of 21.8 months (range, 13-49 months). Mean visual acuity increased by 9.0, 7.9, and 7.9 letters by Month 12, Month 24, and Month 36, respectively. Subgroup analysis revealed a higher risk for fibrosis (odds ratio, 3.30) or atrophy (odds ratio, 3.34) in patients with refractory cysts as compared with refractory subretinal fluid. Furthermore, refractory cysts showed a higher risk for a 10-letter visual acuity loss (P = 0.018).

CONCLUSION

Fluid refractory to monthly treatment with ranibizumab for neovascular age-related macular degeneration still allowed for well-maintained visual improvement, even in subfoveal location. Late fluid resolution may occur. However, refractory cysts were associated with poorer anatomical and functional outcome than subretinal fluid.

LASER RESENSITIZATION OF MEDICALLY UNRESPONSIVE NEOVASCULAR AGE-RELATED MACULAR DEGENERATION: Efficacy and Implications

PURPOSE

Drug tolerance is the most common cause of treatment failure in neovascular age-related macular degeneration. "Low-intensity/high-density" subthreshold diode micropulse laser (SDM) has been reported effective for a number of retinal disorders without adverse effects. It has been proposed that SDM normalizes retinal pigment epithelial function. On this basis, it has been postulated that SDM treatment might restore responsiveness to anti-vascular endothelial growth factor drugs in drug-tolerant eyes.

METHODS

Subthreshold diode micropulse laser treatment was performed in consecutive eyes unresponsive to all anti-vascular endothelial growth factor drugs, including at least three consecutive ineffective aflibercept injections. Monthly aflibercept was resumed 1 month after SDM treatment.

RESULTS

Thirteen eyes of 12 patients, aged 73 to 97 years (average, 84 years), receiving 16 to 67 (average, 34) anti-vascular endothelial growth factor injections before SDM treatment were included and followed for 3 months to 7 months (average, 5 months) after SDM treatment. After SDM treatment and resumption of aflibercept, 92% (12 of 13) of eyes improved, with complete resolution of macular exudation in 69% (9 of 13). Visual acuity remained unchanged. Central and maximum macular thicknesses significantly improved.

CONCLUSION

Subthreshold diode micropulse laser treatment restored drug response in drug-tolerant eyes with neovascular age-related macular degeneration. Based on these findings, a theory of SDM action is proposed, suggesting a wider role for SDM as retinal reparative/protective therapy.

Quantitative OCT subanalysis of eyes with choroidal neovascularization switched from multiple injections of bevacizumab or ranibizumab to intravitreal aflibercept

BACKGROUND AND OBJECTIVE

To assess the early therapeutic response after switching from multiple injections of bevacizumab or ranibizumab to aflibercept in eyes with neovascular age-related macular degeneration (AMD).

PATIENTS AND METHODS

SD-OCT scans of patients with neovascular AMD that was suboptimally responsive to multiple injections of bevacizumab or ranibizumab who were switched to aflibercept were analyzed. After segmenting these scans, the relevant volumes were computed and compared at the various time points by Student's t test.

RESULTS

After switching to aflibercept, converse to the outcome of the last injection of bevacizumab or ranibizumab, statistically significant decreases of 0.32 mm(3) in neurosensory retinal volume, 0.08 mm(3) in subretinal fluid, and 0.56 mm(3) in pigment epithelial detachment were observed (P = .01, .04, and .001, respectively). The mean ETDRS visual acuity increased from 62 to 65 letters after switching (P = .04). These favorable outcomes were sustained after three monthly injections of the new drug.

CONCLUSION

Switching to aflibercept therapy in eyes with persistent fluid after multiple intravitreal injections of bevacizumab or ranibizumab was associated with an early reduction in all fluid compartments and improvement in visual acuity.

Association between choroidal thickness and the response to intravitreal ranibizumab injection in age-related macular degeneration

PURPOSE

To investigate the relationship between the choroidal thicknesses of eyes of patients with age-related macular degeneration (AMD) and the outcomes of intravitreal ranibizumab injection.

METHODS

We reviewed the medical records of 141 consecutive eyes (80 with typical neovascular AMD and 61 with polypoidal choroidal vasculopathy [PCV]) treated by intravitreal ranibizumab and 121 normal control eyes matched in terms of age and spherical equivalent (SE). Eyes of patients were divided into three subgroups with thin, medium and thick choroids. We investigated the relationships between choroidal thickness and treatment outcomes of intravitreal ranibizumab.

RESULTS

In eyes with typical neovascular AMD, thin choroids were associated with older age (linear regression; p < 0.0001) and larger choroidal neovascularization (CNV) lesions (p = 0.049). Patients with thin choroids had a higher prevalence of intra-/subretinal fluid (generalized estimated equation; thin versus medium p < 0.0001; thin versus thick p = 0.003), and less visual gain from baseline to 12 months after treatment, than did other subgroups (linear mixed model; thin versus medium p < 0.0001; thin versus thick p = 0.023). PCV eyes with thick choroids more often had retinal fluid, and eyes with thin choroids experienced more frequent resolution of retinal fluid, from baseline to 12 months after treatment (thick versus medium p < 0.0001, thick versus thin p < 0.0001, thin versus medium p = 0.001). No intergroup difference in post-treatment functional outcome was noted in eyes with PCV (p = 0.584).

CONCLUSIONS

Subfoveal choroidal thickness was associated with functional and anatomical outcomes after intravitreal ranibizumab injection in eyes with typical neovascular AMD and PCV.

Predictability of Recalcitrance in Neovascular Age-Related Macular Degeneration With Indocyanine Green Angiography

PURPOSE

This study aimed to evaluate the utility of indocyanine green (ICG) angiography in predicting recalcitrance in neovascular age-related macular degeneration (nAMD).

DESIGN

A retrospective case series.

METHODS

The charts of treatment-naive subjects with nAMD undergoing anti-vascular endothelial growth factor (anti-VEGF) therapy during a 6-month period were retrospectively reviewed. The study group consisted of subjects with persistent retinal edema on optical coherence tomography (OCT) despite 6 consecutive monthly anti-VEGF injections. The control group was age-matched to the study group and consisted of subjects who demonstrated complete resolution of retinal edema on OCT after 3 or fewer monthly anti-VEGF injections.

RESULTS

There were 42 study cases and 42 controls included in the analysis. The baseline visual acuity, central macular thickness on OCT, and choroidal neovascularization (CNV) surface area on ICG angiography were statistically similar between the study and control groups. The CNV surface area on ICG angiography 2 months after starting consecutive monthly anti-VEGF injections increased from a baseline of 1.78 ± 0.86 to 2.66 ± 0.92 mm2 in the study group (P = 0.008) and decreased from a baseline of 1.94 ± 0.97 to 1.12 ± 0.05 mm2 in the control group (P = 0.04); this change in CNV size on ICG angiography from baseline to 2-month follow-up was statistically significant between the study and control groups (P < 0.0001).

CONCLUSIONS

Change in CNV surface area on ICG angiography can predict which subjects with nAMD are likely to have persistent retinal edema on OCT after 6 or more consecutive monthly anti-VEGF injections.

Ranibizumab and aflibercept for the treatment of wet age-related macular degeneration

INTRODUCTION

Wet age-related macular degeneration (AMD) is a potentially blinding eye disease that causes vision loss among individuals > 50 years old. The main goal in the treatment of wet AMD is to inhibit the choroidal neovascularization (CNV). Currently, ranibizumab and aflibercept are two available anti-VEGF drug for the treatment of wet AMD. Here, we reviewed the clinical outcome of treatment with ranibizumab or aflibercept in patients with wet AMD from recent studies with a special focus on eyes with unusual presentations or treatment resistant and compared these agents with other available wet AMD therapies.

AREAS COVERED

For this review, a literature search from 2011 to present was performed using the following terms (or combination of terms): anti-vascular endothelial growth factors, anti-VEGF, age-related macular degeneration, AMD, aflibercept, and ranibizumab. The studies were limited to studies used ranibizumab, and especially those switched from ranibizumab to aflibercept. Also the clinical trial website (www.clinicaltrials.gov) was searched for recently completed trials of aflibercept or ranibizumab for wet AMD treatment.

EXPERT OPINION

Ranibizumab and aflibercept are effective for the treatment of wet AMD including those with retinal angiomatous proliferation (RAP) and CNV unresponsive to other anti-VEGF agents. Although high-dose ranibizumab has the potential to treat unresponsive CNV, switching to another anti-VEGF agent may be a preferable option in these eyes.

Expression of cytokines on the iris of patients with neovascular glaucoma

PURPOSE

To determine the expression levels of cytokines, including growth factors, inflammatory cytokines, and cell migration associated factors on the iris from subjects with neovascular glaucoma (NVG).

METHODS

After receiving formal consent from 12 subjects with NVG secondary to proliferative diabetic retinopathy and 12 subjects with primary open angle glaucoma (POAG), trabeculectomy was performed and iris specimens were collected during the surgery. Each subject with NVG received intravitreal injection of bevacizumab 1 week prior to the surgery. The mRNA level of vascular endothelial growth factor, basic fibroblastic growth factor, placental-induced growth factor, interleukin-2, interleukin 6, tumour necrosis factor α, intercellular adhesion molecule 1 (ICAM-1) and integrin subunit αV were determined by real-time polymerase chain reaction. The mRNA levels were compared between the two groups.

RESULTS

The mRNA levels of all inflammatory cytokines and integrin subunit αV were significantly increased in the NVG group compared with POAG controls. However, the mRNA level of growth factors and ICAM-1 did not show any difference between the two groups.

CONCLUSIONS

Inflammatory process maybe an important cause of iris neovascularization in subjects with NVG in addition to growth factors alone. Further studies should focus on the effect of growth factors in different phases in the pathogenesis of NVG.

Complement activation and choriocapillaris loss in early AMD: implications for pathophysiology and therapy

Age-related macular degeneration (AMD) is a common and devastating disease that can result in severe visual dysfunction. Over the last decade, great progress has been made in identifying genetic variants that contribute to AMD, many of which lie in genes involved in the complement cascade. In this review we discuss the significance of complement activation in AMD, particularly with respect to the formation of the membrane attack complex in the aging choriocapillaris. We review the clinical, histological and biochemical data that indicate that vascular loss in the choroid occurs very early in the pathogenesis of AMD, and discuss the potential impact of vascular dropout on the retinal pigment epithelium, Bruch's membrane and the photoreceptor cells. Finally, we present a hypothesis for the pathogenesis of early AMD and consider the implications of this model on the development of new therapies.

Multigenic lentiviral vectors for combined and tissue-specific expression of miRNA- and protein-based antiangiogenic factors

Lentivirus-based gene delivery vectors carrying multiple gene cassettes are powerful tools in gene transfer studies and gene therapy, allowing coexpression of multiple therapeutic factors and, if desired, fluorescent reporters. Current strategies to express transgenes and microRNA (miRNA) clusters from a single vector have certain limitations that affect transgene expression levels and/or vector titers. In this study, we describe a novel vector design that facilitates combined expression of therapeutic RNA- and protein-based antiangiogenic factors as well as a fluorescent reporter from back-to-back RNApolII-driven expression cassettes. This configuration allows effective production of intron-embedded miRNAs that are released upon transduction of target cells. Exploiting such multigenic lentiviral vectors, we demonstrate robust miRNA-directed downregulation of vascular endothelial growth factor (VEGF) expression, leading to reduced angiogenesis, and parallel impairment of angiogenic pathways by codelivering the gene encoding pigment epithelium-derived factor (PEDF). Notably, subretinal injections of lentiviral vectors reveal efficient retinal pigment epithelium-specific gene expression driven by the VMD2 promoter, verifying that multigenic lentiviral vectors can be produced with high titers sufficient for in vivo applications. Altogether, our results suggest the potential applicability of combined miRNA- and protein-encoding lentiviral vectors in antiangiogenic gene therapy, including new combination therapies for amelioration of age-related macular degeneration.

A delphi study to detect deficiencies and propose actions in real life treatment of neovascular age-related macular degeneration

Purpose. Spanish retina specialists were surveyed in order to propose actions to decrease deficiencies in real-life neovascular age macular degeneration treatment (nv-AMD). Methods. One hundred experts, members of the Spanish Vitreoretinal Society (SERV), were invited to complete an online survey of 52 statements about nv-AMD management with a modified Delphi methodology. Four rounds were performed using a 5-point Linkert scale. Recommendations were developed after analyzing the differences between the results and the SERV guidelines recommendations. Results. Eighty-seven specialists completed all the Delphi rounds. Once major potential deficiencies in real-life nv-AMD treatment were identified, 15 recommendations were developed with a high level of agreement. Consensus statements to reduce the burden of the disease included the use of treat and extend regimen and to reduce the amount of diagnostic tests during the loading phase and training technical staff to perform these tests and reduce the time between relapse detection and reinjection, as well as establishing patient referral protocols to outside general ophthalmology clinics. Conclusion. The level of agreement with the final recommendations for nv-AMD treatment among Spanish retinal specialist was high indicating that some actions could be applied in order to reduce the deficiencies in real-life nv-AMD treatment.

Treating the untreatable patient: current options for the management of treatment-resistant neovascular age-related macular degeneration

Anti-vascular endothelial growth factor (anti-VEGF) agents represent the current standard of care for neovascular age-related macular degeneration (nAMD). Although effective in a majority of cases, a significant proportion of patients have persisting retinal exudation despite regular anti-VEGF therapy. This exudation is considered to produce poorer visual outcomes in these patients. Some of these patients may have misdiagnosed nAMD variants such as polypoidal choroidal vasculopathy; however, the majority of these eyes have what has been termed treatment-resistant nAMD. Currently, the best way to care for these patients is uncertain. Here, we review the evidence for different approaches to the management of treatment-resistant nAMD, including high-dose anti-VEGF therapy, combination regimes and switching of anti-VEGF agents, and discuss possible therapeutic approaches for patients with treatment-resistant nAMD.

Guidelines for the management of neovascular age-related macular degeneration by the European Society of Retina Specialists (EURETINA)

Age-related macular degeneration (AMD) is still referred to as the leading cause of severe and irreversible visual loss world-wide. The disease has a profound effect on quality of life of affected individuals and represents a major socioeconomic challenge for societies due to the exponential increase in life expectancy and environmental risks. Advances in medical research have identified vascular endothelial growth factor (VEGF) as an important pathophysiological player in neovascular AMD and intraocular inhibition of VEGF as one of the most efficient therapies in medicine. The wide introduction of anti-VEGF therapy has led to an overwhelming improvement in the prognosis of patients affected by neovascular AMD, allowing recovery and maintenance of visual function in the vast majority of patients. However, the therapeutic benefit is accompanied by significant economic investments, unresolved medicolegal debates about the use of off-label substances and overwhelming problems in large population management. The burden of disease has turned into a burden of care with a dissociation of scientific advances and real-world clinical performance. Simultaneously, ground-breaking innovations in diagnostic technologies, such as optical coherence tomography, allows unprecedented high-resolution visualisation of disease morphology and provides a promising horizon for early disease detection and efficient therapeutic follow-up. However, definite conclusions from morphologic parameters are still lacking, and valid biomarkers have yet to be identified to provide a practical base for disease management. The European Society of Retina Specialists offers expert guidance for diagnostic and therapeutic management of neovascular AMD supporting healthcare givers and doctors in providing the best state-of-the-art care to their patients.

TRIAL REGISTRATION NUMBER

NCT01318941.

Impact of vitreomacular adhesion on ranibizumab mono- and combination therapy for neovascular age-related macular degeneration

PURPOSE

To investigate the influence of vitreomacular adhesion on the efficacy of pro re nata (PRN) ranibizumab monotherapy and verteporfin photodynamic therapy (PDT) combination therapy for neovascular age-related macular degeneration.

DESIGN

Post hoc analysis of prospective randomized 12-month multicenter clinical trial data.

METHODS

PATIENT POPULATION

Total of 255 treatment-naïve patients with subfoveal choroidal neovascularization.

OBSERVATION PROCEDURE

Assessment of the vitreomacular interface on monthly optical coherence tomography with division of patients into the following categories according to continuous 1-year grading: posterior vitreous detachment (n=154), dynamic release of vitreomacular adhesion (n=32), stable vitreomacular adhesion (n=51).

MAIN OUTCOME MEASURES

Mean best-corrected visual acuity (BCVA) letter and central retinal thickness changes at month 12 in the vitreomacular interface groups.

RESULTS

Mean BCVA changes at month 12 were +3.5 (posterior vitreous detachment), +4.3 (release of vitreomacular adhesion), and +6.3 (vitreomacular adhesion) in patients receiving monotherapy (P=.767), and +0.1 (posterior vitreous detachment), +6.6 (release of vitreomacular adhesion), and +9.2 (vitreomacular adhesion) in patients receiving combination therapy (P=.009). Mean central retinal thickness changes were -113 μm (posterior vitreous detachment), -89 μm (release of vitreomacular adhesion), and -122 μm (vitreomacular adhesion) in monotherapy (P=.725) and -121 μm (posterior vitreous detachment), -113 μm (release of vitreomacular adhesion), and -113 μm (vitreomacular adhesion) in combination therapy (P=.924). Mean ranibizumab retreatments during 12 months were 4.9 (posterior vitreous detachment), 6.6 (release of vitreomacular adhesion), and 5.3 (vitreomacular adhesion) in monotherapy (P=.018) and 4.7 (posterior vitreous detachment), 5.2 (release of vitreomacular adhesion), and 5.8 (vitreomacular adhesion) in combination therapy (P=.942).

CONCLUSION

This study adds evidence that the vitreomacular interface status impacts functional outcomes and retreatment requirements. Patients with posterior vitreous detachment achieve acceptable results with fewer injections in PRN monotherapy, but lose potential vision gain with PDT. Patients with other vitreomacular interface configurations may potentially achieve optimized vision outcomes by combination of antiangiogenic treatment and vaso-occlusive PDT.

Intraretinal cysts are the most relevant prognostic biomarker in neovascular age-related macular degeneration independent of the therapeutic strategy

BACKGROUND/AIMS

To investigate the impact of antiangiogenic monotherapy and photodynamic therapy (PDT) as add-on strategy on retinal morphology, and to analyse prognostic biomarkers for visual outcome and retreatment frequency in neovascular age-related macular degeneration (nAMD).

METHODS

255 patients participating in the MONT BLANC study were evaluated. Patients were randomised to receive as-needed ranibizumab monotherapy or combination therapy (verteporfin PDT and ranibizumab). Outcome measures included visual acuity (VA), retinal morphology assessed by optical coherence tomography and retreatment frequency.

RESULTS

The proportion of scans showing intraretinal cysts (IRC) or subretinal fluid (SRF) decreased more intensively in the combination than in the monotherapy group. Pigment epithelial detachments (PED) decreased significantly only in the combination group. Patients with IRC presented the lowest initial VA, and IRC had the strongest negative predictive value for functional improvement in both groups. SRF showed a predictive value for a higher number of ranibizumab injections (combination, +0.9; monotherapy, +0.8) and a higher number of PDT treatments in the combination group (+0.3). PED was associated with a higher number of ranibizumab injections only in the monotherapy group (+1.2).

CONCLUSIONS

Combination and monotherapy showed a distinct response pattern for morphological parameters in nAMD. IRC was the only relevant prognostic parameter for functional outcome.

TRIAL REGISTRATION NUMBER

NCT00433017.

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.