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Visudyne is the first and only light-activated therapy indicated for the treatment of patients with predominantly classic subfoveal choroidal neovascularization (CNV) secondary to wet AMD, as well as pathologic myopia (PM) and ocular histoplasmosis syndrome (OHS).
Intended to help preserve visual acuity and slow or stop the advancement of CNV, Visudyne utilizes a lipophilic molecule (known as verteporfin) to occlude abnormal blood vessels found in the eye while sparing overlying retinal tissue.1 Used according to TAP protocol, Visudyne therapy has been shown to significantly reduce the risk of severe vision loss and slow the progression of AMD.2
TAP Protocol: Visudyne Every 3 Months If Leakage Is Present*3
Visudyne is a multicourse therapy. Per recommended guidelines, patients should receive therapy once every 3 months as long as leakage appears on fluorescein angiography. In the 2-year TAP Investigation, Visudyne patients received an average of 3.4 treatments in the first year and 2.0 treatments the second year.2 Although the number of treatments per patient may vary, a “full course of therapy” is considered complete when the patient is no longer presenting with leakage or bleeding on angiography. To learn more about Visudyne therapy, click here.
Visudyne therapy is a 2-stage process requiring both the intravenous administration of verteporfin and the application of non-thermal red light.
Upon injection, verteporfin is transported in the plasma primarily by lipoproteins. The drug is then activated by non-thermal light, which when applied in the presence of oxygen, results in the creation of highly reactive, short-lived singlet oxygen and oxygen free radicals. These molecules in turn cause selective damage to the neovascular endothelium, resulting in vessel occlusion. Damaged endothelial tissue is known to release procoagulant and vasoactive factors through the lipo-oxygenase (leukotriene) and cyclo-oxygenase (eicosanoids such as thromboxane) pathways, resulting in platelet aggregation, fibrin clot formation, and vasoconstriction.
Treatment is straightforward and simple. Therapy is performed as an outpatient procedure and usually takes no longer than 30 minutes. Visudyne therapy is relatively painless and does not require general anesthesia.
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