MyVisionTest News Archive
Dec 14, 2009
Synergistic effect of low fluence PDT plus Avastin for AMD
Intravitreal Avastin (bevacizumab) and low fluence photodynamic therapy (PDT) have a synergistic effect when applied together in the treatment of neonascular age-related macular degeneration (AMD), according to a new research report.
PDT is performed by intravenous administration of a drug know as verteporfin, then activating the drug within the retina using a laser. When verteporfin is activated by laser light, it generates singlet oxygen and free radicals, leading to occlusion of the choroidal neovascular membrane (CNV) and surrounding vessels. Because of concerns regarding vision loss following PDT, clinicians have attempted to improve outcomes by reducing the amount of laser energy used during the procedure. This is known as low fluence PDT, as opposed to standard PDT. Researchers have also attempted to improve PDT outcomes by combining PDT with intravitreal steroid injection.
This prospective comparative interventional study included 85 patients with treatment naive classic, or predominantly classic, subfoveal CNV secondary to AMD. Patients were randomly assigned to receive either Avastin alone or Avastin plus low fluence PDT. In the combination therapy group, PDT with verteporfin was delivered with low fluence rate (300mW/cm(2) for 83 seconds, 25 J/cm(2)). The follow-up was scheduled at 1-,3-,6-, 9- and 12-months.
Eyes without recurrence received a mean of 2.8 Avastin injections in the Avastin-only treatment group, or 1.4 Avastin injections in the combination therapy group. Eyes with recurrence received a mean of 3.2 injections vs 2.2 injections in the Avastin monotherapy and combination therapy groups, respectively. The difference in re-injection rate between the two groups was statistically significant (P =0.03). Visual acuity improvement was not statistically significant between the two groups (P=0.31).
The investigators conclude that the combination of Avastin with low fluence PDT for the treatment of classic or predominantly classic neovascular AMD works in a synergistic fashion with a significant reduction in the re-injection rate.
Read more...
Br J Ophthalmol. 2009 Dec 3. [Epub ahead of print]
Tags: Avastin, photodynamic therapy, combo therapy, wet AMD
Intravitreal Avastin (bevacizumab) and low fluence photodynamic therapy (PDT) have a synergistic effect when applied together in the treatment of neonascular age-related macular degeneration (AMD), according to a new research report.PDT is performed by intravenous administration of a drug know as verteporfin, then activating the drug within the retina using a laser. When verteporfin is activated by laser light, it generates singlet oxygen and free radicals, leading to occlusion of the choroidal neovascular membrane (CNV) and surrounding vessels. Because of concerns regarding vision loss following PDT, clinicians have attempted to improve outcomes by reducing the amount of laser energy used during the procedure. This is known as low fluence PDT, as opposed to standard PDT. Researchers have also attempted to improve PDT outcomes by combining PDT with intravitreal steroid injection.
Eyes without recurrence received a mean of 2.8 Avastin injections in the Avastin-only treatment group, or 1.4 Avastin injections in the combination therapy group. Eyes with recurrence received a mean of 3.2 injections vs 2.2 injections in the Avastin monotherapy and combination therapy groups, respectively. The difference in re-injection rate between the two groups was statistically significant (P =0.03). Visual acuity improvement was not statistically significant between the two groups (P=0.31).
The investigators conclude that the combination of Avastin with low fluence PDT for the treatment of classic or predominantly classic neovascular AMD works in a synergistic fashion with a significant reduction in the re-injection rate.
Read more...
Br J Ophthalmol. 2009 Dec 3. [Epub ahead of print]
