In a dramatic change from a decades- long tradition, ARVO convened its annual meeting this May in a place other than Florida, as ophthalmologists and vision scientists headed to the Pacific Northwest for ARVO 2013. While many attendees may have felt some trepidation about the change, by the end of the week most agreed that sunny Seattle was a terrific choice. The relaxed atmosphere of the city provided a pleasant setting for scientifi c discourse and socializing with colleagues old and new. Plus, it wasn’t hard to find a good sandwich shop, café or restaurant close by, which is always a bonus.
This month, we’ll review the highlights of the meeting in various areas of vision research. (Unless otherwise specified, all of the abstract citations are from this year: IOVS 2013;54.)
The scientifi c headliner of this year’s meeting was the AREDS2 trial,
There were no significant differences in disease progression in the four major treatment groups. The probability of progression to advanced AMD was 31 percent in the placebo group, 29 percent in the lutein + zeaxanthin group, 31 percent in the DHA + EPA group and 30 percent in the lutein + zeaxanthin and DHA + EPA group. There was also no signifi – cant difference between the two zinc concentrations tested. One subgroup, consisting of patients receiving lutein + zeaxanthin and no beta-carotene, saw an 18-percent reduction in the risk of progression to advanced AMD when compared to those who took AREDS with beta-carotene (and no lutein + zeaxanthin). Study authors also noted that this replacement of beta carotene in the original formulation with lutein + zeaxanthin reduced the risk for lung cancer in ex-smokers.
A key aspect of therapeutic development is the refinement and optimization of methods for patient inclusion in studies and disease assessment. Ocular inflammation is an area of active effort, and many presenters reported on their attempts to improve protocol design, symptom evaluation or both.
Investigators from our research fi rm, Ora, used modifications to the traditional conjunctival allergen challenge protocol to elicit a more chronic, inflammatory conjunctivitis that may be a means for developing treatments for chronic allergy. (Gomes P, et al. ARVO E-Abstract 2555) Other refinements included updated protocols for fl uorophotometry and conjunctival staining. (Heckley C, et al. ARVO E-Abstract 6043; Lane K, et al. ARVO E-Abstract 6045) The optimization of fl uorometric measures of tear turnover was particularly intriguing, because the authors were able to show a signifi cant correlation between this sign of dry-eye disease and the Ocular Surface Disease Index symptomatology scale, a noteworthy accomplishment for clinical studies of this disease.
Advances in ocular surface microscopy was a dominant topic, as well. Studies of corneal nerve morphology by in vivo confocal microscopy demonstrated the utility of enhanced ocular surface imaging, both as a potential diagnostic tool and as a potential therapeutic endpoint. (Sanchez Dalmau BF, et al. ARVO E-Abstract 530; You JY, et al. ARVO E-Abstract 531) Other presentations focused on IVCM-based advances in limbal morphology and on infl ammatory cell infiltration of the conjunctival vasculature. (Baclagon ER, et al. ARVO E-Abstract 537; Angeli E, et al. ARVO E-Abstract 2557)
A big topic in clinical methodology for ocular inflammation was the measurement of biomarkers of disease with a focus on those found in tears. A number of groups reported efforts to identify both normal and pathological values for cytokines in tears. (Hagan S, et al. ARVO E-Abstract 955; Enriquez- De-Salamanca A, et al. ARVO E-Abstract 2072; Dionne K et al. ARVO E-Abstract 4324; Lakshman N et al. ARVO E-Abstract 4325) While there were some disagreements on the quantitative aspects of these studies, it’s clear that the technology to accurately measure picogram quantities of signaling molecules including IL-2, IL-6 and IL-8 is here, and such measurements will become an increasingly important aspect of diagnosis going forward.
Biomarker assessment was not limited to cytokine studies, and other presentations described quantification of other potential indicators or predictors of ocular disease. One study provided evidence that several micro RNAs associated with retinal degeneration can be detected in systemic circulation, and so may ultimately function as biomarkers for retinal disease. (Peng Q, et al. ARVO E-Abstract 1947) These short-chain nucleic acid molecules function as regulators of gene transcription in a tissue-specifi c manner. The potential importance of miRNAs (particularly miRNA-96 and miRNA-124) was confirmed in other presentations examining the role of these molecules in retinal degeneration. (Langmann T, et al. ARVO E-Abstract 4517)
There were a number of presentations that provided new insights on the measures used to assess blink rates and the importance of considering lid contact time to differentiate between normal and dry-eye subjects. (Johnston P, et al. ARVO E-Abstract 967; Lafond A, et al. ARVO E-Abstract 962) Other presenters examined the relationship between tear meniscus dimensions and other disease measures in subcategories of dry eye and found that in patients with aqueous tear deficient dry eye and autoimmune disease, lower tear volume is associated with worse corneal epithelial disease. (Tung CI, et al. ARVO E-Abstract 970)
Mucin function in dry eye was also the subject of multiple presentations. One presentation found that as the signs of dry eye worsen, soluble MUC16 values increase. (Watson M, et al. ARVO E-Abstract 4309) Another study used a polymerase chain reaction-based measure of MUC5A expression to screen for goblet cells in patients with limbal cell deficiency. The goal of this study was to correlate loss of this key cell type with disease severity. (Suarez-Cortes TM, et al. ARVO E-Abstract 547)
Ora presented novel data on the use of software analysis for the evaluation of corneal superfi cial punctate keratitis, an important primary endpoint for dry-eye trials. (Rodriguez J, et al. ARVO- E Abstract 4341) Clinical grading, typically based on a 0-to-4 point scale, poses many challenges, such as inefficiencies in reproducibility, accuracy, subjectivity and sensitivity. In a population of 665 dry-eye subjects, the software-based approach generated accurate, efficient quantification of corneal desiccation. An automated approach is useful in standardizing the SPK evaluation process and allows for clear identification of improvement due to therapeutic intervention. Automation may not be applicable in every situation, however. In another study, comparison of software-based analysis of hyperemia grading showed that while this approach may be useful for dry-eye studies, confounding factors in allergic hyperemia (such as chemosis) preclude the use of automated redness analyzers. (Raval Y, et al. ARVO E-Abstract 2553)
Dry eye is a disease that involves a range of functional tests of tear fi lm stability, but despite this it’s still not clear which tests are best. One group sought to address this topic by calculating the correlations of dry-eye signs to signs, symptoms to symptoms, and both signs and symptoms to objective tests of tear-film stability. Contrary to many other reports, the authors reported that many signs and symptoms correlate with quality-of-life variables. In addition, they found a stronger correlation between tear turnover rate and symptoms than that seen between Schirmer’s tests and symptomatology. Lid variables, however, correlated in unexpected ways, and the authors suggest that compensatory mechanisms may underlie these findings. (Saigal S, et al. ARVO E-Abstract 4361)
In addition to the preclinical presentations, ARVO always presents a good opportunity to see what may be in the pipeline of new therapeutics. We came across a number of interesting posters throughout the week, including some on Thursday, the last day of the meeting. Just in case you weren’t able to stick around through the end of the week, we’ll provide a recap here, as a number of the “bestin- show” posters were presented on ARVO’s final day.
A group of investigators, one of whom is an employee for Aerpio Therapeutics (Cincinnati, Ohio) provided in vitro and in vivo data on the company’s drug AKB-9778. (Shen J, et al. ARVO E-Abstract 6094) The researchers confirmed its bioactivity as a potent and selective small molecule inhibitor of vascular endothelial-protein tyrosine phosphatase. The VEPTP enzyme, also known as human protein phosphatase β or HPTBβ, is a negative regulator of the Tie2 receptor, which is expressed on vascular endothelial cells and plays a key role in stabilizing blood vessels. Inhibition of VE-PTP restores Tie2 signaling, reducing vascular leak and pathologic neovascularization. In the study, the researchers note that, in vitro, “AKB- 9778 promoted phosphorylation of Tie2, enhanced angiopoietin (Ang)-1 induced Tie2 phosphorylation, and stimulated phosphorylation of signaling molecules in the Tie2 pathway.” In vivo, AKB-9778 also induced phosphorylation of Tie2. While AKB-9778 is initially being developed for diabetic macular edema, vascular stabilization may also provide benefits for a wide variety of disease states. Aerpio initiated a Phase Ib/IIa trial of AKB- 9778 for the treatment of DME in September 2012.
The agent ALG-1001 is being investigated in several vascular eye diseases including wet AMD, DME and symptomatic vitreomacular adhesion. ALG-1001 is a new small-molecule oligopeptide that targets multiple integrin receptor sites that play key roles in cell signaling and regulating cellular shape, motility and the cell cycle. Interim data on the Phase Ib/ IIa dose-ranging, monotherapy study of the drug in wet AMD was presented at this year’s ARVO.
Monday’s retina posters included a meta analysis of ranibizumab safety data in patients with AMD, retinal vein occlusion or DME. (Avery RL, et al. ARVO E-Abstract 1535) The analysis pooled 22 Phase II, III and IIIb studies and included 10,300 patients with a mean follow-up time of 15.9 months. In the analysis, patients with DME showed higher mortality rates and a greater rate of wound healing complications than those with either AMD or RVO. No other patterns of systemic disease emerged from the study.
As our experience with therapeutic responses to either ranibizumab or bevacizumab is extended, it’s important to examine the distinctions in therapeutic responses observed to these and other anti-VEGF based therapies. This was addressed in a retrospective study of aflibercept efficacy in patients who had previously received treatment with either ranibizumab or bevacizumab. (Yonekawa Y, et al. ARVO E-Abstract 1938) Mean central macular thickness, visual acuity and treatment history were collected from 94 patients (104 eyes) in two treatment centers. Although the follow-up was modest (average of 18 weeks), signifi cant reduction in CMT was observed in two patient populations: patients who were refractory to ranibizumab or bevacizumab and those who received aflibercept after a recurrence of disease progression. Both groups also showed a stabilization of VA following aflibercept. Thus, despite similar mechanisms of action, aflibercept appears to be a useful therapeutic option in patients previously treated with other VEGF antagonists.
Data implicating B-Amyloid in the pathology of glaucoma, as analyzed via levels of B-Amyloid in glaucomatous retinas compared to healthy subjects, set the stage for MRZ-99030, a B-Amyloid aggregation modulator.
The treatment landscape for vitreomacular adhesions changed when ocriplasmin (Jetrea; Thrombogenics NV, Leuven, Belgium) was approved by the FDA in 2012.
Building off data presented at last year’s ARVO (Van de Velde S, et al. IOVS 2012;53:ARVO E-Abstract 1977; Sijnave D, et al. IOVS 2012;53:ARVO E-Abstract 2522; Hollanders K, et al. IOVS 2012;53:ARVO E-Abstract 1974), Amakem Therapeutics (Diepenbeek, Belgium) presented new preclinical data on its lead drug candidate, the locally acting Rho kinase (ROCK) inhibitor AMA0076. In Dutch Belted rabbits, once-daily treatment with AMA0076 resulted in IOP reduction that was more sustained than Y-39983, a non-local ROCK inhibitor. (Van de Velde S, et al. ARVO E-Abstract 5631) The data demonstrated that AMA0076 elicited a sustained, 24-hour effect on lowering intraocular pressure, an effect not seen with Y-39983. Additionally, hyperemia was observed with Y-39983 at all concentrations, whereas only mild hyperemia was observed with the highest concentration (0.4%) of AMA0076. Looking ahead, Amakem initiated a Phase IIa proof-of-concept, placebo controlled, dose-escalation study of topical AMA0076 in September 2012.
Data implicating β-Amyloid in the pathology of glaucoma, as analyzed via levels of β-Amyloid in human glaucomatous retinas in comparison to healthy subjects, set the stage for MRZ-99030 (Merz Pharmaceuticals; Frankfurt, Germany), a β-Amyloid aggregation modulator. (von Thun und Hohenstein-Blaul N, et al. ARVO EAbstract 1139) Merz researchers found that the topically administered drug signifi cantly reduced retinal ganglion cell apoptosis in a rodent model of glaucoma compared to vehicle control in a dose-dependent manner. (Gravius A, et al. ARVO E-Abstract 2625)
Multiple abstracts from Japan’s Ono Pharmaceuticals highlighted ONO- 9054, an isopropyl ester derivative of the free acid ONO-AG-367 classifi ed as a dual FP/EP3 receptor agonist that may be effective in lowering intraocular pressure. (Tomohiro K, et al. ARVO E-Abstract 766; Karakawa T, et al. ARVO E-Abstract 1998) In dogs and monkeys, the IOP-lowering effects of ONO-9054 were more potent and longer-lasting than the effects produced by an FP receptor agonist (latanoprost), a beta-adrenergic receptor antagonist (timolol) and a fi xed combination of the two. (Nagai K, et al. ARVO E-Abstract 1986) In a doublemasked study of 48 healthy volunteers, ONO-9054 was well-tolerated and there were no apparent dose-related responses in any systemic or local tolerability parameters. (Rowe-Rendleman C, et al. ARVO E-Abstract 440)
Mimetogen (Montréal, Québec) presented post-hoc data from a completed trial of MIM-D3 Ophthalmic Solution. Patients with greater or more rapid exacerbation of signs and symptoms from Ora’s CAE were more responsive to MIM-D3, which targets mucin-protective compensatory mechanisms. (Ousler G, et al. ARVO E-Abstract 4343) Additionally, the post-hoc analysis supports an association between the duration of dry eye and the response to treatment for the reduction in both signs and symptoms. (Meerovich K, et al. ARVO E-Abstract 4340) Patients who reported having dry eye for fi ve to 10 years saw a significant reduction in fluorescein staining and experienced improvements in their dry-eye symptoms, as opposed to those patients who reported having dry-eye disease for durations of one to fi ve years or greater than 10 years.
Also targeted to treat ocular surface orders such as dry eye, EBI-005 is a potent IL-1R1 inhibitor. Eleven Biotherapeutics (Cambridge, Mass.) presented clinical data from a Phase I safety study demonstrating that EBI-005 was safe and well-tolerated in normal volunteers at two dose levels when administered three times daily. (Goldstein M, et al. ARVO EAbstract 4319) The positive results of the Phase 1a study prompted a Phase 1b study in patients with dry eye. Eleven also presented preclinical toxicology data demonstrating that EBI-005 was well-tolerated in both mouse and rabbit. (Furfi ne E, et al. ARVO E-Abstract 4320)
Preclinical data on a new topically administered anti-infl ammatory, cis- Urocanic acid, demonstrated a significant reduction in corneal staining using a murine model of dry eye in a study from Ora. (Whitlock A, et al. ARVO E-Abstract 902) The same compound also showed promise in an Ora preclinical study of allergic conjunctivitis, so we’re likely to see additional studies of cis-UCA in the future. (McLaughlin J, et al. ARVO E-Abstract 2554)
An interesting wrinkle in the therapeutic development paradigm was described by two poster presentations on the effi cacy of low-dose brimonidine as an eye-whitener. (Chapin MJ et al. ARVO E-Abstract 2556; Horn G et al. ARVO E-Abstract 5451) (One of the presenters is the patent holder for this use of brimonidine.) The re-purposing of this anti-glaucoma agent provides a great example of how clinicians may be the best untapped resource in the drug development landscape. It also reminds us why we like the ARVO meeting: It represents a unique opportunity for clinicians and scientists to rub elbows, share ideas and move ocular therapeutics forward.
Dr. Abelson is a clinical professor of ophthalmology at Harvard Medical School.