Verteporfin Therapy and Triamcinolone Acetonide: Convergent Modes of Action for Treatment of Neovascular Age-Related Macular Degeneration

Therapeutic Modalities of Exudative Age-related Macular Degeneration

Introduction:

Age-related macular degeneration (AMD) is a leading cause of irreversible serious vision damage in persons over 50 years of age. In treating AMD many medicaments are applied such as inhibitors of vascular endothelial growth factor (VEGF), have been very carefully included over the last few years after a series of study research.

Aims:

To analyze the past methods of treatment, discuss emerging therapies which could advance the treatment of exudative AMD. The past anti-VEGF therapies require frequent repetitions of administration, with uncertain visual acuity recovery, as not all patients react to anti-VEGF therapy. Consequently, there is a need to find out additional therapies which could improve the treatment of exudative AMD. The real aim in the treating of AMD is to prevent CNV development.

Methods:

A survey of the current clinical research and results in the field of the present and future treatments of exudative AMD.

Results:

There are many areas of research into new methods of the exudative AMD treatment.

Conclusion:

The future therapies for exudative AMD treatment have a potential not only to reduce the frequency of administration and follow-up visits, but also to improve effects of treatment by targeting additional ways of CNV development, increasing the aptitude of target binding and extending durability of treatment.

Verteporfin combination regimens in the treatment of neovascular age-related macular degeneration

BACKGROUND

Neovascular age-related macular degeneration is characterized by choroidal neovascularization that has a complex pathogenesis. Combining agents that have different mechanisms of action (i.e., verteporfin photodynamic therapy, antivascular endothelial growth factor, and/or anti-inflammatory therapies) could maximize clinical benefits through potential complementary effects. This review discusses findings from studies investigating this hypothesis.

METHODS

Articles were retrieved from PubMed using relevant search terms. Abstracts from recent scientific meetings and details of ongoing trials from clinicaltrials.gov were also included.

RESULTS

Following its approval, verteporfin was important in the management of choroidal neovascularization due to age-related macular degeneration for several years. Improved visual outcomes have now been reported with antiangiogenic agents (e.g., intravitreal ranibizumab), especially when frequently administered. Results from investigator-sponsored trials, retrospective case studies and Registries, which have provided insights into the latest findings from clinical practice in the "real-world" setting, as well as randomized controlled trials, suggest that a combination approach is generally well tolerated and may maintain improvements in visual and anatomic outcomes with fewer retreatments.

CONCLUSION

A rationale exists for investigating combination approaches to target different processes in choroidal neovascularization pathogenesis, which may optimize treatment benefits in neovascular age-related macular degeneration. Encouraging data suggest that combination strategies are not associated with major adverse events.

Photodynamic therapy with verteporfin in age-related macular degeneration: a systematic review of efficacy, safety, treatment modifications and pharmacoeconomic properties

Photodynamic therapy (PDT) with verteporfin has been used less comprehensively in the treatment of exudative age-related macular degeneration (AMD), and specifically of choroidal neovascularization (CNV), since the advent of antiangiogenic therapies. Recently, there has been a renewed interest in PDT as an adjunct to these and other agents in the treatment of neovascular AMD. In light of this new development and the European Medicines Evaluation Agency's (EMEA) recent labelling decision to rescind approval for the use of PDT in occult CNV lesions, the present systematic review was undertaken to revisit the evidence supporting its clinical application. Photodynamic therapy provided the first pharmacological treatment for patients suffering from subfoveal CNV, the major cause of severe vision loss in AMD. Key clinical trials evaluating efficacy and safety have examined patients with all lesion subtypes, with the primary labelled indication (i.e. lesions containing a classic component of > or = 50% ) deriving from the results of the Treatment of Age-related Macular Degeneration with Photodynamic Therapy (TAP) Study. The subsequent TAP Study Group post hoc categorization of lesions as predominantly classic is open to question, however, as it appears that the overall efficacy in this group only may have reflected the especially strong response in 100% classic lesions. Based on a subgroup analysis of the Verteporfin in Photodynamic Therapy Study, the indication for PDT subsequently was expanded in some jurisdictions, including that of the EMEA, to include occult lesions with no classic component. However, the subsequent Visudyne in Occult Study found no benefit in 100% occult lesions, resulting in the EMEA rescinding its approval for this indication.

Combination of photodynamic therapy and immunomodulation: current status and future trends

Photodynamic therapy (PDT) has been used for the treatment of nonmalignant and malignant diseases from head to toe. Over the last decade its clinical application has gained increasing acceptance around the world. Pre-clinical studies demonstrate that, in addition to the direct local cytotoxicity and vascular effects, PDT can induce various host immune responses. Recent clinical data also show that improved clinical outcomes are obtained through the combination of PDT and immunomodulation. This review will summarize and discuss recent progress in developing innovative regimen of PDT combined with immunomodulation for the treatment of both nonmalignant and malignant diseases.

Effect of posterior juxtascleral triamcinolone acetonide on the efficacy and choriocapillaris hypoperfusion of photodynamic therapy

PURPOSE

To evaluate the effect of posterior juxtascleral triamcinolone acetonide (TA) injection combined with photodynamic therapy with verteporfin (PDT) for treating exudative age-related macular degeneration (AMD), the best-corrected visual acuity (BCVA), the retreatment rates and the rate of choroidal hypoperfusion were investigated.

METHODS

A total of 67 eyes with subfoveal choroidal neovascularization (CNV) due to AMD were included. Forty-four eyes underwent PDT alone (PDT-alone group), and 23 eyes underwent PDT with the posterior juxtascleral injection of TA (PDT+TA group). Every 3 months after the PDT, the eyes were evaluated with regard to BCVA and requirement for retreatment by fluorescein angiography (FA) with the aid of optical coherence tomography (OCT). Choroiocapillaris hypoperfusion was assessed by indocyanine green angiography (ICGA) at 3 and 12 months. All patients completed a 1-year follow-up.

RESULTS

At the baseline, there was no difference in lesion type, size or visual acuity between the two groups. At 1 year, the change in BCVA was -0.0811 logarithm of the minimum angle of resolution (LogMAR) in the PDT-alone group, compared with -0.0432 logMAR in the PDT+TA group. There was no significant difference in the change in BCVA between the two groups (P = 0.6910). The PDT+TA group required a lower mean number of treatments (1.64 compared with 2.34 [P = 0.0223]) and showed a higher rate of choriocapillaris occlusion at 3 months, but no significant difference at 1 year (P = 0.9243)

CONCLUSIONS

Fewer retreatments were required in the TA+PDT group. There was no significant difference in the change in BCVA between the two groups. Adjacent TA may promote short-term choriocapillaris hypoperfusion.