Macular Degeneration: Husain D

Husain D, Ambati B, Adamis AP, Miller JW. · Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, 243 Charles Street, Boston, MA 02114, USA. · Ophthalmol Clin North Am. · Pubmed #12064086 No free full text.

Abstract: AMD is a poorly understood disease at this time. Since it is the leading cause of blindness in the elderly in the developed world, there is a pressing need for better treatment. Therefore, there is extensive ongoing research in both pathogenesis and therapy of AMD. Epidemiological studies have shown significant risk associated with increasing age and cigarette smoking, future studies may identify environmental risk factors though at present studies have been inconclusive. Genetic studies may identify subgroups of disease and thus help provide a selective approach to treatment. The vascular model of AMD may provide better understanding of the blood flow and post capillary resistance and help in early and newer intervention in the disease. Vascular endothelial growth factor has been extensively studied in choroidal neovascularization. It has been demonstrated in human and animal models of CNV and VEGF antagonists are currently in clinical trial. Extensive work is ongoing to prevent and treat CNV with antiangiogenic agents.

Husain D, Kim I, Gauthier D, Lane AM, Tsilimbaris MK, Ezra E, Connolly EJ, Michaud N, Gragoudas ES, O'Neill CA, Beyer JC, Miller JW. · Angiogenesis and Laser Laboratory, Retina Service, Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA. · Arch Ophthalmol. · Pubmed #15824225 No free full text.

Abstract: OBJECTIVE: To study the safety and efficacy of intravitreal injections of anti-vascular endothelial growth factor antibody fragment (ranibizumab [formerly known as rhuFabV2], Lucentis; Genentech, South San Francisco, Calif) in combination with intravenous verteporfin (Visudyne; Novartis, East Hanover, NJ) photodynamic therapy (PDT) on experimental choroidal neovascularization in the monkey eye. METHODS: Choroidal neovascularization was induced by laser injury in both eyes of cynomolgus monkeys and followed with weekly fundus photography and fluorescein angiography. Two weeks after induction, weekly treatments were initiated. These treatments included using either an intravitreal injection of ranibizumab (previously known as rhuFabV2) in combination with verteporfin PDT or a ranibizumab vehicle (placebo) in combination with verteporfin PDT (PDT only). Six animals (group 1) initially received intravitreal injections followed 1 week later by PDT. Four animals (group 2) initially received PDT followed 1 week later by intravitreal injection. Two animals (group 3) received injections and PDT on the same day at 2-week intervals. Photodynamic therapy was applied in all 3 groups every 2 weeks for 3 treatments with follow-up through 2 weeks after the last PDT treatment. Fluorescein angiograms were graded using a masked standardized protocol. The data were analyzed using the McNemar chi(2) test for matched pairs. RESULTS: No choroidal neovascularization leakage was observed in the eyes of animals treated with ranibizumab and PDT at day 21 or 42 after the start of the first treatment. Leakage persisted in eyes treated with PDT alone at 21 days (3 of 12 eyes) and 42 days (2 of 12 eyes). At all time points studied, the ranibizumab and PDT-treated eyes experienced better angiographic outcomes than the eyes receiving PDT alone. CONCLUSION: These preliminary data indicate that an intravitreal ranibizumab injection in combination with verteporfin PDT (ranibizumab and PDT) causes a greater reduction in angiographic leakage than PDT and intravitreal vehicle injection (PDT only) in experimental choroidal neovascularization. CLINICAL RELEVANCE: This combination therapy can potentially offer a new treatment modality for choroidal neovascularization in patients with macular degeneration and other diseases.