Abstract
Purpose: :
To study the safety and efficacy of combining Macugen® and photodynamic therapy with Visudyne® (PDT) in the treatment of neovascular age–related macular degeneration (AMD).
Methods: :
Case series of subjects with choroidal neovascularization secondary to age–related macular degeneration. Subjects were treated with Macugen 0.3mg every 6 weeks, and this was combined with PDT every 3 months if judged necessary by the investigator.
Results: :
Functional outcomes based on changes in visual acuity and anatomical outcomes based on fluorescein angiography and optical coherence tomography will be presented. No additional safety concerns were observed in combining these two therapies compared to the safety profiles of each individual treatment modality.
Conclusions: :
Vascular endothelial growth factor (VEGF) has been implicated in angiogenesis and vascular hyperpermeability in ocular diseases like neovascular AMD. Preclinical data suggests that anti–VEGF therapies may be less effective after new vessels have achieved more advanced stages of "maturation." "Mature" vessels tend not to regress following anti–VEGF therapy like Macugen, hence using other therapeutic modalities with different mechanisms of action could enhance final outcomes. An alternative to regressing new vessels could be applying treatments with destructive properties like PDT. However, besides the risk of permanent damage to the choriocapillaries and retina, PDT up–regulates VEGF. Therefore, a restricted use of PDT to close the neovascular complex associated with chronic anti–VEGF therapy to prevent neovascular regrowth with minimum risks could be an optimal approach for the treatment of choroidal neovascularization. This concept is supported by the results of an early phase clinical trial study of Macugen that enrolled 10 patients to combined PDT and Macugen at baseline, followed by Macugen administration every 28 days for a total of 3 injections. At Day 85, patients experienced an improvement in mean visual acuity of 11.6 letters. Six (60%) patients gained 3 or more lines of vision.
Keywords: choroid: neovascularization • age-related macular degeneration • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials