Randomized Trial to Evaluate Tandospirone in Geographic Atrophy Secondary to Age-Related Macular Degeneration: The GATE Study

PURPOSE

To determine the safety and efficacy of AL-8309B (tandospirone) in the management of patients with geographic atrophy (GA) secondary to age-related macular degeneration (AMD) and obtain standardized data on GA lesion growth progression.

DESIGN

Prospective, controlled, double-masked, randomized, multicenter phase 3 clinical trial.

METHODS

setting: Forty-eight clinical sites.

PATIENTS

Patients with GA associated with AMD were enrolled. All patients were followed for a minimum of 30 months, and up to 36 months. intervention procedures: Patients were randomized (1:1:1) to receive AL-8309B ophthalmic solution 1.0%, 1.75%, or vehicle, administered as a twice-daily topical ocular drop.

MAIN OUTCOME MEASURES

The primary efficacy endpoint was mean annualized lesion enlargement from baseline as assessed with fundus autofluorescence (FAF) imaging.

RESULTS

A total of 768 eyes of 768 patients were enrolled and treated with AL-8309B 1.0% (n = 250), AL-8309B 1.75% (n = 258), or vehicle (n = 260). An increase in mean lesion size was observed in both the AL-8309B and vehicle treatment groups, and growth rates were similar in all treatment groups. Annualized lesion growth rates were 1.73, 1.76, and 1.71 mm(2) for AL-8309B 1.0%, AL-8309B 1.75%, and vehicle, respectively.

CONCLUSIONS

AL-8309B 1.0% and 1.75% did not affect lesion growth in eyes with GA secondary to AMD. There were no clinically relevant safety issues identified for AL-8309B. The large natural history dataset from this study is a valuable repository for future comparisons.

Treatment of exudative age-related macular degeneration with a designed ankyrin repeat protein that binds vascular endothelial growth factor: a phase I/II study

PURPOSE

To evaluate the safety, tolerability and bioactivity of ascending doses of MP0112, a designed ankyrin repeat protein (DARPin) that binds with high affinity to vascular endothelial growth factor-A (VEGF-A), in treatment-naive patients with exudative age-related macular degeneration (AMD).

DESIGN

Phase I/II, open-label, multicenter, dose-escalation study.

METHODS

Patients were to receive a single intravitreal injection of MP0112 at doses ranging from 0.04 to 3.6 mg and be monitored for 16 weeks for safety, efficacy, pharmacokinetics, and dose response.

RESULTS

Altogether, 32 patients received a single injection of MP0112. The maximum tolerated dose was 1.0 mg because of a case of endophthalmitis in the 2.0 mg cohort. Drug-related adverse events were reported by 13 (41%) of 32 patients; they included ocular inflammation in 11 patients (7 mild, 4 moderate in severity). Visual acuity scores were stable or improved compared with baseline for ≥4 weeks following injection; both retinal thickness and fluorescein angiography leakage decreased in a dose-dependent manner. Rescue therapy was administered to 20 (91%) of 22 patients who received 0.04-0.4 mg MP0112 compared with 4 of 10 (40%) patients who received 1.0 or 2.0 mg. Of patients in the higher-dose cohorts who did not require rescue treatment, 83% (5/6) maintained reductions in central retinal thickness through week 16.

CONCLUSIONS

A single injection of 1.0 or 2.0 mg MP0112 resulted in mean decreases in retinal thickness and leakage area despite ocular inflammation. Larger-scale studies are warranted to confirm these observations.

Graph-based multi-surface segmentation of OCT data using trained hard and soft constraints

Optical coherence tomography (OCT) is a well-established image modality in ophthalmology and used daily in the clinic. Automatic evaluation of such datasets requires an accurate segmentation of the retinal cell layers. However, due to the naturally low signal to noise ratio and the resulting bad image quality, this task remains challenging. We propose an automatic graph-based multi-surface segmentation algorithm that internally uses soft constraints to add prior information from a learned model. This improves the accuracy of the segmentation and increase the robustness to noise. Furthermore, we show that the graph size can be greatly reduced by applying a smart segmentation scheme. This allows the segmentation to be computed in seconds instead of minutes, without deteriorating the segmentation accuracy, making it ideal for a clinical setup. An extensive evaluation on 20 OCT datasets of healthy eyes was performed and showed a mean unsigned segmentation error of 3.05 ±0.54 μm over all datasets when compared to the average observer, which is lower than the inter-observer variability. Similar performance was measured for the task of drusen segmentation, demonstrating the usefulness of using soft constraints as a tool to deal with pathologies.

Pathology hinting as the combination of automatic segmentation with a statistical shape model

With improvements in acquisition speed and quality, the amount of medical image data to be screened by clinicians is starting to become challenging in the daily clinical practice. To quickly visualize and find abnormalities in medical images, we propose a new method combining segmentation algorithms with statistical shape models. A statistical shape model built from a healthy population will have a close fit in healthy regions. The model will however not fit to morphological abnormalities often present in the areas of pathologies. Using the residual fitting error of the statistical shape model, pathologies can be visualized very quickly. This idea is applied to finding drusen in the retinal pigment epithelium (RPE) of optical coherence tomography (OCT) volumes. A segmentation technique able to accurately segment drusen in patients with age-related macular degeneration (AMD) is applied. The segmentation is then analyzed with a statistical shape model to visualize potentially pathological areas. An extensive evaluation is performed to validate the segmentation algorithm, as well as the quality and sensitivity of the hinting system. Most of the drusen with a height of 85.5 microm were detected, and all drusen at least 93.6 microm high were detected.

Small dense particles in the retina observable by spectral-domain optical coherence tomography in age-related macular degeneration

PURPOSE

To observe detailed changes in neurosensory retinal structure after anti-VEGF upload in age-related macular degeneration (AMD), by using spectral domain optical coherence tomography (SD-OCT).

METHODS

The retinal structure was observed by using SD-OCT in 61 patients, before and 1 month after the third ranibizumab injection (upload phase). The main focus of attention was a subjective determination of the amount and behavior of the numerous small, dense particles (SDPs) frequently observed within the outer and inner neurosensory layers in eyes with neovascular AMD. The Spearman rho correlation was used for statistical analysis.

RESULTS

In all eyes, various amounts of SDPs were seen within the neurosensory layer of the foveal and parafoveal area. In 54%, the amount of SDPs became significantly less after ranibizumab therapy (stable, 41%; higher, 5%). SDP reduction correlated positively with the reduction of retinal disease according to OCT (P = 0.000), with central foveal thickness (P = 0.040), and with the improvement in best corrected visual acuity (BCVA; P = 0.006). The baseline amount of SDPs also correlated positively with the increase in BCVA (P = 0.005).

CONCLUSIONS

The origin of the SDPs observable in SD-OCT is unknown, but they may represent migrating RPE cells or leukocytes, indicating a certain status of retinal inflammation. The amount of SDPs is substantially reduced after ranibizumab upload therapy and correlates positively with BCVA. Moreover, an initial large number of SDPs may indicate a higher grade of inflammation, but the presence of a high number enhances the effect of ranibizumab therapy. Thus, the amount of SDPs before treatment may be a predictive factor for the therapy's outcome.

Spectral-domain optical coherence tomography use in macular diseases: a review

The introduction of spectral-domain optical coherence tomography (SD-OCT) has improved the clinical value for assessment of the eyes with macular disease. This article reviews the advances of SD-OCT for the diagnostic of various macular diseases. These include vitreomacular traction syndrome, cystoid macular edema/diabetic macular edema, epiretinal membranes, full-thickness macular holes, lamellar holes, pseudoholes, microholes, and schisis from myopia. Besides offering new insights into the pathogenesis of macular abnormalities, SD-OCT is a valuable tool for monitoring macular disease.

Treatment of branch retinal vein occlusion induced macular edema with bevacizumab

BACKGROUND

Branch retinal vein occlusion is a frequent cause of visual loss with currently insufficient treatment options. We evaluate the effect of Bevacizumab (Avastin) treatment in patients with macular edema induced by branch retinal vein occlusion.

METHODS

Retrospective analysis of 32 eyes in 32 patients with fluorescein angiography proven branch retinal vein occlusion, macular edema and Bevacizumab treatment. Outcome measures were best corrected visual acuity in logMAR and central retinal thickness in OCT.

RESULTS

Visual acuity was significantly better 4 to 6 weeks after Bevacizumab treatment compared to visual acuity prior to treatment (before 0.7 +/- 0.3 and after 0.5 +/- 0.3; mean +/- standard deviation; p < 0.01, paired t-test). Gain in visual acuity was accompanied by a significant decrease in retinal thickness (454 +/- 117 to 305 +/- 129 microm, p < 0.01, paired t-test). Follow up (170, 27 - 418 days; median, range) shows that improvement for both visual acuity and retinal thickness last for several months after Bevacizumab use.

CONCLUSION

We present evidence that intravitreal Bevacizumab is an effective and lasting treatment for macular edema after branch retinal vein occlusion.