Test-Retest Variability and Discriminatory Power of Measurements From Microperimetry and Dark Adaptation Assessment in People With Intermediate Age-Related Macular Degeneration - A MACUSTAR Study Report.

Purpose: The purpose of this study was to assess test-retest variability and discriminatory power of measures from macular integrity assessment (S-MAIA) and AdaptDx. Methods: This is a cross-sectional study of 167 people with intermediate age-related macular degeneration (iAMD), no AMD (controls; n = 54), early AMD (n = 28), and late AMD (n = 41), recruited across 18 European ophthalmology centers. Repeat measures of mesopic and scotopic S-MAIA average (mean) threshold (MMAT decibels [dB] and SMAT [dB]) and rod intercept time (RIT [mins]) at 2 visits 14 (±7) days apart were recorded. Repeat measures were assessed by Bland-Altman analysis, intra-class correlation coefficients (ICCs) and variability ratios. Secondary analysis assessed the area under the receiver operating characteristic curves (AUC) to determine the ability to distinguish people as having no AMD, early AMD, or iAMD. Results: Data were available for 128, 131, and 103 iAMD participants for the mesopic and scotopic S-MAIA and AdaptDx, respectively. MMAT and SMAT demonstrate similar test-retest variability in iAMD (95% confidence interval [CI] ICC of 0.79-0.89 and 0.78-0.89, respectively). ICCs were worse in RIT (95% CI ICC = 0.55-0.77). All tests had equivalent AUCs (approximately 70%) distinguishing between subjects with iAMD and controls, whereas early AMD was indistinguishable from iAMD on all measures (AUC = <55%). A learning effect was not seen in these assessments under the operating procedures used. Conclusions: MMAT, SMAT, and RIT have adequate test-retest variability and are all moderately good at separating people with iAMD from controls. Translational Relevance: Expected levels of test-retest variability and discriminatory power of the AdaptDx and MAIA devices in a clinical study setting must be considered when designing future trials for people with AMD.

Disease-specific assessment of Vision Impairment in Low Luminance in age-related macular degeneration - a MACUSTAR study report.

BACKGROUND/AIMS: To further validate the Vision Impairment in Low Luminance (VILL) questionnaire, which captures visual functioning and vision-related quality of life (VRQoL) under low luminance, low-contrast conditions relevant to age-related macular degeneration (AMD). METHODS: The VILL was translated from German into English (UK), Danish, Dutch, French, Italian and Portuguese. Rasch analysis was used to assess psychometric characteristics of 716 participants (65% female, mean age 72±7 years, 82% intermediate AMD) from the baseline visit of the MACUSTAR study. In a subset of participants (n=301), test-retest reliability (intraclass correlation coefficient (ICC) and coefficient of repeatability (CoR)) and construct validity were assessed. RESULTS: Four items were removed from the VILL with 37 items due to misfit. The resulting Vision Impairment in Low Luminance with 33 items (VILL-33) has three subscales with no disordered thresholds and no misfitting items. No differential item functioning and no multidimensionality were observed. Person reliability and person separation index were 0.91 and 3.27 for the Vision Impairment in Low Luminance Reading Subscale (VILL-R), 0.87 and 2.58 for the Vision Impairment in Low Luminance Mobility Subscale (VILL-M), and 0.78 and 1.90 for the Vision Impairment in Low Luminance Emotional Subscale (VILL-E). ICC and CoR were 0.92 and 1.9 for VILL-R, 0.93 and 1.8 for VILL-M and 0.82 and 5.0 for VILL-E. Reported VRQoL decreased with advanced AMD stage (p<0.0001) and was lower in the intermediate AMD group than in the no AMD group (p≤0.0053). CONCLUSION: The VILL is a psychometrically sound patient-reported outcome instrument, and the results further support its reliability and validity across all AMD stages. We recommend the shortened version of the questionnaire with three subscales (VILL-33) for future use. TRIAL REGISTRATION NUMBER: NCT03349801.

Characteristics and Spatial Distribution of Structural Features in Age-Related Macular Degeneration: A MACUSTAR Study Report.

PURPOSE: To report the prevalence and topographic distribution of structural characteristics in study participants with age-related macular degeneration (AMD) and controls in the cross-sectional study part of the MACUSTAR study (ClinicalTrials.gov Identifier: NCT03349801). DESIGN: European, multicenter cohort study. SUBJECTS: Overall, 301 eyes of 301 subjects with early (n = 34), intermediate (n = 168), and late AMD (n = 43), as well as eyes without any AMD features (n = 56). METHODS: In study eyes with intermediate AMD (iAMD), the presence of structural AMD biomarkers, including pigmentary abnormalities (PAs), pigment epithelium detachment (PED), refractile deposits, reticular pseudodrusen (RPD), hyperreflective foci (HRF), incomplete/complete retinal pigment epithelium (RPE), and outer retinal atrophy (i/cRORA), and quiescent choroidal neovascularization (qCNV) was systematically determined in the prospectively acquired multimodal retinal imaging cross-sectional data set of MACUSTAR. Retinal layer thicknesses and the RPE drusen complex (RPEDC) volume were determined for the total study cohort in spectral-domain (SD) OCT imaging using a deep-learning-based algorithm. MAIN OUTCOME MEASURES: Prevalence and topographic distribution of structural iAMD features. RESULTS: A total of 301 study eyes of 301 subjects with a mean (± standard deviation) age of 71.2 ± 7.20 years (63.1% women) were included. Besides large drusen, the most prevalent structural feature in iAMD study eyes were PA (57.1%), followed by HRF (51.8%) and RPD (22.0%). Pigment epithelium detachment lesions were observed in 4.8%, vitelliform lesions in 4.2%, refractile deposits in 3.0%, and qCNV in 2.4%. Direct precursor lesions for manifest retinal atrophy were detected in 10.7% (iRORA) and 4.2% (cRORA) in iAMD eyes. Overall, the highest RPEDC volume with a median of 98.92 × 10-4 mm³ was found in iAMD study eyes. Spatial analysis demonstrated a predominant distribution of RPD in the superior and temporal subfields at a foveal eccentricity of 1.5 to 2 mm, whereas HRF and large drusen had a distinct topographic distribution involving the foveal center. CONCLUSIONS: Detailed knowledge of the prevalence and distribution of structural iAMD biomarkers is vital to identify reliable outcome measure for disease progression. Longitudinal analyses are needed to evaluate their prognostic value for conversion to advanced disease stages. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Complement factor B is critical for sub-RPE deposit accumulation in a model of Doyne honeycomb retinal dystrophy with features of age-related macular degeneration.

EFEMP1 R345W is a dominant mutation causing Doyne honeycomb retinal dystrophy/malattia leventinese (DHRD/ML), a rare blinding disease with clinical pathology similar to age-related macular degeneration (AMD). Aged Efemp1  R345W/R345W knock-in mice (Efemp1ki/ki) develop microscopic deposits on the basal side of retinal pigment epithelial cells (RPE), an early feature in DHRD/ML and AMD. Here, we assessed the role of alternative complement pathway component factor B (FB) in the formation of these deposits. RNA-seq analysis of the posterior eyecups revealed increased unfolded protein response, decreased mitochondrial function in the neural retina (by 3 months of age) and increased inflammatory pathways in both neural retina and posterior eyecups (at 17 months of age) of Efemp1ki/ki mice compared with wild-type littermate controls. Proteomics analysis of eye lysates confirmed similar dysregulated pathways as detected by RNA-seq. Complement activation was increased in aged Efemp1ki/ki eyes with an approximately 2-fold elevation of complement breakdown products iC3b and Ba (P < 0.05). Deletion of the Cfb gene in female Efemp1ki/ki mice partially normalized the above dysregulated biological pathway changes and oral dosing of a small molecule FB inhibitor from 10 to 12 months of age reduced sub-RPE deposits by 65% (P = 0.029). In contrast, male Efemp1ki/ki mice had fewer sub-RPE deposits than age-matched females, no elevation of ocular complement activation and no effect of FB inhibition on sub-RPE deposits. The effects of FB deletion or inhibition on Efemp1ki/ki mice supports systemic inhibition of the alternative complement pathway as a potential treatment of dry AMD and DHRD/ML.

Comparability of automated drusen volume measurements in age-related macular degeneration: a MACUSTAR study report.

Drusen are hallmarks of early and intermediate age-related macular degeneration (AMD) but their quantification remains a challenge. We compared automated drusen volume measurements between different OCT devices. We included 380 eyes from 200 individuals with bilateral intermediate (iAMD, n = 126), early (eAMD, n = 25) or no AMD (n = 49) from the MACUSTAR study. We assessed OCT scans from Cirrus (200 × 200 macular cube, 6 × 6 mm; Zeiss Meditec, CA) and Spectralis (20° × 20°, 25 B-scans; 30° × 25°, 241 B-scans; Heidelberg Engineering, Germany) devices. Sensitivity and specificity for drusen detection and differences between modalities were assessed with intra-class correlation coefficients (ICCs) and mean difference in a 5 mm diameter fovea-centered circle. Specificity was > 90% in the three modalities. In eAMD, we observed highest sensitivity in the denser Spectralis scan (68.1). The two different Spectralis modalities showed a significantly higher agreement in quantifying drusen volume in iAMD (ICC 0.993 [0.991-0.994]) than the dense Spectralis with Cirrus scan (ICC 0.807 [0.757-0.847]). Formulae for drusen volume conversion in iAMD between the two devices are provided. Automated drusen volume measures are not interchangeable between devices and softwares and need to be interpreted with the used imaging devices and software in mind. Accounting for systematic difference between methods increases comparability and conversion formulae are provided. Less dense scans did not affect drusen volume measurements in iAMD but decreased sensitivity for medium drusen in eAMD.Trial registration: ClinicalTrials.gov NCT03349801. Registered on 22 November 2017.

A proteogenomic signature of age-related macular degeneration in blood.

Age-related macular degeneration (AMD) is one of the most common causes of visual impairment in the elderly, with a complex and still poorly understood etiology. Whole-genome association studies have discovered 34 genomic regions associated with AMD. However, the genes and cognate proteins that mediate the risk, are largely unknown. In the current study, we integrate levels of 4782 human serum proteins with all genetic risk loci for AMD in a large population-based study of the elderly, revealing many proteins and pathways linked to the disease. Serum proteins are also found to reflect AMD severity independent of genetics and predict progression from early to advanced AMD after five years in this population. A two-sample Mendelian randomization study identifies several proteins that are causally related to the disease and are directionally consistent with the observational estimates. In this work, we present a robust and unique framework for elucidating the pathobiology of AMD.

Repeatability and Discriminatory Power of Chart-Based Visual Function Tests in Individuals With Age-Related Macular Degeneration: A MACUSTAR Study Report.

Importance: There is a need for validated clinical end points that are reliably able to quantify potential therapeutic effects of future treatments targeting age-related macular degeneration (AMD) before the onset of serious visual impairment. Objective: To assess the reliability and discriminatory power of 5 simple chart-based visual function (VF) tests as potential measures for clinical trial end points with regulatory and patient-access intention in intermediate AMD (iAMD). Design, Setting, and Participants: This international noninterventional study took place at 18 tertiary ophthalmology departments across Europe. Participants were recruited between April 2018 and March 2020 and were identified during routine clinical review. Participants with no AMD and early AMD were recruited from hospital staff, friends, and family of participants with AMD and via referrals from community ophthalmologists and optometrists. The repeatability and discriminatory power of 5 simple chart-based assessments of VF (best-corrected visual acuity [BCVA], low-luminance visual acuity [LLVA], Moorfields Acuity Test [MAT], Pelli-Robson Contrast Sensitivity [CS], and International Reading Speed Test [IReST]) were assessed in a repeated-measures design. VF assessments were performed on day 0 and day 14. Participants with early AMD, iAMD, late AMD, and no AMD were recruited. Main Outcomes and Measures: Intraclass correlation coefficients (ICCs) and Bland-Altman 95% limits of agreement (LoA) were computed to assess repeatability. Area under the receiver operating characteristic curves (AUCs) determined the discriminatory ability of all measures to classify individuals as having no AMD or iAMD and to differentiate iAMD from its neighboring disease states. Results: A total of 301 participants (mean [SD] age, 71 [7] years; 187 female participants [62.1%]) were included in the study. Thirty-four participants (11.3%) had early AMD, 168 (55.8%) had iAMD, 43 (14.3%) had late AMD, and 56 (18.6%) had no AMD. ICCs for all VF measures ranged between 0.88 and 0.96 when all participants were considered, indicating good to excellent repeatability. All measures displayed excellent discrimination between iAMD and late AMD (AUC, 0.92-0.99). Early AMD was indistinguishable from iAMD on all measures (AUC, 0.54-0.64). CS afforded the best discrimination between no AMD and iAMD (AUC, 0.77). Under the same conditions, BCVA, LLVA, and MAT were fair discriminators (AUC, 0.69-0.71), and IReST had poor discrimination (AUC, 0.57-0.61). Conclusions and Relevance: BCVA, LLVA, MAT, CS, and IReST had adequate repeatability in this multicenter, multiexaminer setting but limited power to discriminate between no AMD and iAMD. The prognostic power of these variables to predict conversion from iAMD to late AMD is being examined in the ongoing longitudinal part of the MACUSTAR study.

A Randomized, Double-Masked, Multicenter Trial of Topical Acrizanib (LHA510), a Tyrosine Kinase VEGF-Receptor Inhibitor, in Treatment-Experienced Subjects With Neovascular Age-Related Macular Degeneration.

PURPOSE: To evaluate whether topical acrizanib (LHA510), a small-molecule vascular endothelial growth factor receptor inhibitor, could suppress the need for anti-vascular endothelial growth factor therapy over a 12-week period in patients with neovascular age-related macular degeneration. DESIGN: A phase 2 multicenter randomized double-masked, vehicle-controlled proof-of-concept study. METHODS: Trial includes n = 90 patients with active choroidal neovascularization due to neovascular age-related macular degeneration and under anti-vascular endothelial growth factor treatment. All patients received an intravitreal injection of ranibizumab at baseline and were retreated when there was evidence of disease recurrence (rescue). Patients were randomized 1:1 to receive topical LHA510 or vehicle for 12 weeks. Drops were administered twice a day for 8 weeks and then 3 times a day for the last 4 weeks. MAIN OUTCOME MEASURE: The primary outcome was the number of patients requiring rescue over 84 days of topical dosing. Key secondary outcome measures were time to first rescue, total number of ranibizumab injections, changes in central subfield thickness, and changes of visual acuity from baseline to day 84. RESULTS: The extended per protocol set included 70 patients of whom 25 of 33 patients in the LHA510 group (75.8%) and 25 of 37 patients in the placebo group (67.6%) required rescue by day 84 (P = .8466). Secondary and subgroup analysis did not support evidence of efficacy. Twenty-one of 46 patients administered LHA510 developed a reversible corneal haze that resolved with cessation of treatment and did not recur in patients restarted at once daily frequency. CONCLUSION: In spite of extensive optimization for topical efficacy, LHA510 failed to demonstrate clinical efficacy.

Differential and Altered Spatial Distribution of Complement Expression in Age-Related Macular Degeneration.

Purpose: Dysregulation of the alternative complement pathway is a major pathogenic mechanism in age-related macular degeneration. We investigated whether locally synthesized complement components contribute to AMD by profiling complement expression in postmortem eyes with and without AMD. Methods: AMD severity grade 1 to 4 was determined by analysis of postmortem acquired fundus images and hematoxylin and eosin stained histological sections. TaqMan (donor eyes n = 39) and RNAscope/in situ hybridization (n = 10) were performed to detect complement mRNA. Meso scale discovery assay and Western blot (n = 31) were used to measure complement protein levels. Results: The levels of complement mRNA and protein expression were approximately 15- to 100-fold (P < 0.0001-0.001) higher in macular retinal pigment epithelium (RPE)/choroid tissue than in neural retina, regardless of AMD grade status. Complement mRNA and protein levels were modestly elevated in vitreous and the macular neural retina in eyes with geographic atrophy (GA), but not in eyes with early or intermediate AMD, compared to normal eyes. Alternative and classical pathway complement mRNAs (C3, CFB, CFH, CFI, C1QA) identified by RNAscope were conspicuous in areas of atrophy; in those areas C3 mRNA was observed in a subset of IBA1+ microglia or macrophages. Conclusions: We verified that RPE/choroid contains most ocular complement; thus RPE/choroid rather than the neural retina or vitreous is likely to be the key site for complement inhibition to treat GA or earlier stage of the disease. Outer retinal local production of complement mRNAs along with evidence of increased complement activation is a feature of GA.

Screening Medications for Association with Progression to Wet Age-Related Macular Degeneration.

PURPOSE: There is an urgent need for treatments that prevent or delay development to advanced age-related macular degeneration (AMD). Drugs already on the market for other conditions could affect progression to neovascular AMD (nAMD). If identified, these drugs could provide insights for drug development targets. The objective of this study was to use a novel data mining method that can simultaneously evaluate thousands of correlated hypotheses, while adjusting for multiple testing, to screen for associations between drugs and delayed progression to nAMD. DESIGN: We applied a nested case-control study to administrative insurance claims data to identify cases with nAMD and risk-set sampled controls that were 1:4 variable ratio matched on age, gender, and recent healthcare use. PARTICIPANTS: The study population included cases with nAMD and risk set matched controls. METHODS: We used a tree-based scanning method to evaluate associations between hierarchical classifications of drugs that patients were exposed to within 6 months, 7 to 24 months, or ever before their index date. The index date was the date of first nAMD diagnosis in cases. Risk-set sampled controls were assigned the same index date as the case to which they were matched. The study was implemented using Medicare data from New Jersey and Pennsylvania, and national data from IBM MarketScan Research Database. We set an a priori threshold for statistical alerting at P ≤ 0.01 and focused on associations with large magnitude (relative risks ≥ 2.0). MAIN OUTCOME MEASURES: Progression to nAMD. RESULTS: Of approximately 4000 generic drugs and drug classes evaluated, the method detected 19 distinct drug exposures with statistically significant, large relative risks indicating that cases were less frequently exposed than controls. These included (1) drugs with prior evidence for a causal relationship (e.g., megestrol); (2) drugs without prior evidence for a causal relationship, but potentially worth further exploration (e.g., donepezil, epoetin alfa); (3) drugs with alternative biologic explanations for the association (e.g., sevelamer); and (4) drugs that may have resulted in statistical alerts due to their correlation with drugs that alerted for other reasons. CONCLUSIONS: This exploratory drug-screening study identified several potential targets for follow-up studies to further evaluate and determine if they may prevent or delay progression to advanced AMD.

Amount of Mononuclear Phagocyte Infiltrate Does Not Predict Area of Experimental Choroidal Neovascularization (CNV).

PURPOSE: Mononuclear phagocytes (MNPs) are present in neovascular age-related macular degeneration (nv AMD) which is also called choroidal neovascularization (CNV). The number and phenotype of the MNPs depend upon the local environment in the CNV and effect of nv AMD therapy. We investigated ocular cell infiltration and conditions that modulate angiogenesis in a laser-induced mouse CNV model. METHODS: We developed assays to quantify MNPs in our established mouse CNV model. One MNP assay quantified the number of subretinal cells peripheral to the CNV lesions. A second assay semiquantitatively assesses the number of MNPs localized to the CNV lesion. We used these assays to measure the effect of toll-like receptor-2 (TLR-2) activation, anti-vascular endothelial growth factor (VEGF) therapy, and chemokine (C-C motif) ligand 2 (Ccl2) genetic deletion on MNP infiltration after laser injury. RESULTS: Laser injury induced blood vessel growth and infiltration of MNPs. Systemic administration of a TLR-2 activating peptide increased laser-induced CNV area, MNP cell numbers, and MNP density over the CNV lesions. Systemic administration of a VEGF antibody reduced CNV area, while Ccl2 genetic deletion increased CNV area. Despite the change in amount of angiogenesis, MNP infiltration was, surprisingly, unchanged in these 2 conditions. CONCLUSIONS: MNP quantification provides biological insights for candidate AMD therapies. The number of infiltrating MNP cells does not correlate with the amount of laser-induced CNV area.

The Discovery of N-(1-Methyl-5-(trifluoromethyl)-1H-pyrazol-3-yl)-5-((6- ((methylamino)methyl)pyrimidin-4-yl)oxy)-1H-indole-1-carboxamide (Acrizanib), a VEGFR-2 Inhibitor Specifically Designed for Topical Ocular Delivery, as a Therapy for Neovascular Age-Related Macular Degeneration.

A noninvasive topical ocular therapy for the treatment of neovascular or "wet" age-related macular degeneration would provide a patient administered alternative to the current standard of care, which requires physician administered intravitreal injections. This manuscript describes a novel strategy for the use of in vivo models of choroidal neovascularization (CNV) as the primary means of developing SAR related to efficacy from topical administration. Ultimately, this effort led to the discovery of acrizanib (LHA510), a small-molecule VEGFR-2 inhibitor with potency and efficacy in rodent CNV models, limited systemic exposure after topical ocular administration, multiple formulation options, and an acceptable rabbit ocular PK profile.

Long-acting protein drugs for the treatment of ocular diseases.

Protein drugs that neutralize vascular endothelial growth factor (VEGF), such as aflibercept or ranibizumab, rescue vision in patients with retinal vascular diseases. Nonetheless, optimal visual outcomes require intraocular injections as frequently as every month. Here we report a method to extend the intravitreal half-life of protein drugs as an alternative to either encapsulation or chemical modifications with polymers. We combine a 97-amino-acid peptide of human origin that binds hyaluronan, a major macromolecular component of the eye's vitreous, with therapeutic antibodies and proteins. When administered to rabbit and monkey eyes, the half-life of the modified proteins is increased ∼3-4-fold relative to unmodified proteins. We further show that prototype long-acting anti-VEGF drugs (LAVAs) that include this peptide attenuate VEGF-induced retinal changes in animal models of neovascular retinal disease ∼3-4-fold longer than unmodified drugs. This approach has the potential to reduce the dosing frequency associated with retinal disease treatments.

Core Replacements in a Potent Series of VEGFR-2 Inhibitors and Their Impact on Potency, Solubility, and hERG.

Anti-VEGF therapy has been a clinically validated treatment of age-related macular degeneration (AMD). We have recently reported the discovery of indole based oral VEGFR-2 inhibitors that provide sustained ocular retention and efficacy in models of wet-AMD. We disclose herein the synthesis and the biological evaluation of a series of novel core replacements as an expansion of the reported indole based VEGFR-2 inhibitor series. Addition of heteroatoms to the existing core and/or rearranging the heteroatoms around the 6-5 bicyclic ring structure produced a series of compounds that generally retained good on-target potency and an improved solubility profile. The hERG affinity was proven not be dependent on the change in lipophilicity through alteration of the core structure. A serendipitous discovery led to the identification of a new indole-pyrimidine connectivity: from 5-hydroxy to 6-hydroxyindole with potentially vast implication on the in vitro/in vivo properties of this class of compounds.

Discovery of Oral VEGFR-2 Inhibitors with Prolonged Ocular Retention That Are Efficacious in Models of Wet Age-Related Macular Degeneration.

The benefit of intravitreal anti-VEGF therapy in treating wet age-related macular degeneration (AMD) is well established. Identification of VEGFR-2 inhibitors with optimal ADME properties for an ocular indication provides opportunities for dosing routes beyond intravitreal injection. We employed a high-throughput in vivo screening strategy with rodent models of choroidal neovascularization and iterative compound design to identify VEGFR-2 inhibitors with potential to benefit wet AMD patients. These compounds demonstrate preferential ocular tissue distribution and efficacy after oral administration while minimizing systemic exposure.

Lack of involvement of CEP adducts in TLR activation and in angiogenesis.

Proteins that are post-translationally adducted with 2-(ω-carboxyethyl)pyrrole (CEP) have been proposed to play a pathogenic role in age-related macular degeneration, by inducing angiogenesis in a Toll Like Receptor 2 (TLR2)-dependent manner. We have investigated the involvement of CEP adducts in angiogenesis and TLR activation, to assess the therapeutic potential of inhibiting CEP adducts and TLR2 for ocular angiogenesis. As tool reagents, several CEP-adducted proteins and peptides were synthetically generated by published methodology and adduction was confirmed by NMR and LC-MS/MS analyses. Structural studies showed significant changes in secondary structure in CEP-adducted proteins but not the untreated proteins. Similar structural changes were also observed in the treated unadducted proteins, which were treated by the same adduction method except for one critical step required to form the CEP group. Thus some structural changes were unrelated to CEP groups and were artificially induced by the synthesis method. In biological studies, the CEP-adducted proteins and peptides failed to activate TLR2 in cell-based assays and in an in vivo TLR2-mediated retinal leukocyte infiltration model. Neither CEP adducts nor TLR agonists were able to induce angiogenesis in a tube formation assay. In vivo, treatment of animals with CEP-adducted protein had no effect on laser-induced choroidal neovascularization. Furthermore, in vivo inactivation of TLR2 by deficiency in Myeloid Differentiation factor 88 (Myd88) had no effect on abrasion-induced corneal neovascularization. Thus the CEP-TLR2 axis, which is implicated in other wound angiogenesis models, does not appear to play a pathological role in a corneal wound angiogenesis model. Collectively, our data do not support the mechanism of action of CEP adducts in TLR2-mediated angiogenesis proposed by others.

Reliability of the mouse model of choroidal neovascularization induced by laser photocoagulation.

PURPOSE: We attempted to reproduce published studies that evaluated whether the following factors influence choroidal neovascularization (CNV) induced by laser photocoagulation in murine retinas: small interfering RNA (siRNA), cobra venom factor, complement factors C3 and C5, and complement receptor C5aR. In addition, we explored whether laser-induced CNV in mice was influenced by the vendor of origin of the animals. METHODS: Reagents or genotypes reported by others to influence CNV in this model were assessed using our standard procedures. Retrospective analyses of control or placebo mice in many experiments were done to evaluate whether the CNV area induced by laser photocoagulation varied according to vendor. RESULTS: Administration of the following agents did not have a substantial impact on the CNV induced by laser burns in mice: siRNA, low-molecular-weight inhibitor of the C5a receptor (PMX53), or cobra venom factor. Jackson Laboratory (JAX) mice lacking either C3 or C5 had increased neovascularization compared to non-littermate JAX wild-type controls. Taconic mice lacking C3 had reduced CNV compared to non-littermate Taconic wild-type control mice. A retrospective analysis of vehicle-treated wild-type C57BL/6 mice used as controls across 132 experiments conducted from 2007 to 2010 revealed that mice purchased from JAX or from Charles River produced less neovascularization than mice from Taconic. CONCLUSIONS: We present our recommended methods for conducting experiments with the mouse laser-induced CNV model to enhance reproducibility and minimize investigator bias.

Risk segmentation related to the offering of a consumer-directed health plan: a case study of Humana Inc.

OBJECTIVE: To determine whether the offering of a consumer-directed health plan (CDHP) is likely to cause risk segmentation in an employer group. STUDY SETTING AND DATA SOURCE: The study population comprises the approximately 10,000 people (employees and dependents) enrolled as members of the employee health benefit program of Humana Inc. at its headquarters in Louisville, Kentucky, during the benefit years starting July 1, 2000, and July 1, 2001. This analysis is based on primary collection of claims, enrollment, and employment data for those employees and dependents. STUDY DESIGN: This is a case study of the experience of a single employer in offering two consumer-directed health plan options ("Coverage First 1" and "Coverage First 2") to its employees. We assessed the risk profile of those choosing the Coverage First plans and those remaining in more traditional health maintenance organization (HMO) and preferred provider organization (PPO) coverage. Risk was measured using prior claims (in dollars per member per month), prior utilization (admissions/1,000; average length of stay; prescriptions/1,000; physician office visit services/1,000), a pharmacy-based risk assessment tool (developed by Ingenix), and demographics. DATA COLLECTION/EXTRACTION METHODS: Complete claims and administrative data were provided by Humana Inc. for the two-year study period. Unique identifiers enabled us to track subscribers' individual enrollment and utilization over this period. PRINCIPAL FINDINGS: Based on demographic data alone, there did not appear to be a difference in the risk profiles of those choosing versus not choosing Coverage First. However, based on prior claims and prior use data, it appeared that those who chose Coverage First were healthier than those electing to remain in more traditional coverage. For each of five services, prior-year usage by people who subsequently enrolled in Coverage First 1 (CF1) was below 60 percent of the average for the whole group. Hospital and maternity admissions per thousand were less than 30 percent of the overall average; length of stay per hospital admission, physician office services per thousand, and prescriptions per thousand were all between 50 and 60 percent of the overall average. Coverage First 2 (CF2) subscribers' prior use of services was somewhat higher than CF1 subscribers', but it was still below average in every category. As with prior use, prior claims data indicated that Coverage First subscribers were healthier than average, with prior total claims less than 50 percent of average. CONCLUSIONS: In this case, the offering of high-deductible or consumer-directed health plan options alongside more traditional options caused risk segmentation within an employer group. The extent to which these findings are applicable to other cases will depend on many factors, including the employer premium contribution policies and employees' perception of the value of the various plan options. Further research is needed to determine whether risk segmentation will worsen in future years for this employer and if so, whether it will cause premiums for more traditional health plans to increase.