A review of the role and efficacy of anti-VEGF therapy in macular disease

September 15, 2009

A review of the role and efficacy of anti-VEGF therapy in macular disease

Barcelona-The proportion of aging individuals increases steadily and now figures show that 7.5 million people will suffer AMD-related vision loss by 2020, Ursula Schmidt-Erfurth, MD, told delegates of the European Society of Cataract and Refractive Surgeons. Very severe AMD causes a similar reduction in the quality of life (QOL) as a severe stroke, she said.

“AMD has a devastating impact on patient QOL and improvements in QOL correlate with improved visual acuity,” she said.

Treatment with anti-VEGFs is associated with improvements in new VFQ 25, depending on the efficacy of the drug used. “Comparison trials are necessary for each drug and each regimen,” she said.

In a review of anti-VEGF treatments, Dr. Schmidt-Erfurth said that ranibizumab (Lucentis, Genentech) was by far the most effective treatment in two studies, ANCHOR and MARINA.

In an upcoming paper in Ophthalmology, Dr. Schmidt Erfurth will show that intraocular VEGF during fixed ranibizumab therapy disappears as long as the monthly treatments continue.

“Patients gain the most vision over the first three months,” she said. “There is a simultaneous functional and morphologic effect, with rapid, significant and maintained benefit.”

She added that there was a significant quality of life improvement with optimal results at month three. She said in relation to the issue of a loading dose, one injection with subsequent evaluation was recommended.

The optimal benefit of ranibizumab comes from fixed monthly treatment, as shown by the ANCHOR and MARINA studies, whereas the PIER study show that benefit was lost with quarterly monthly treatments.

Meanwhile the SUSTAIN study showed that there was a relative maintenance of benefit with a flexible monthly therapy combined with fixed monitoring, in other words regular monitoring and therapy as required. “This is the real world scenario,” said Dr. Schmidt-Erfurth.

Timing is very important in the therapy-as-required regime. “If the loss occurred one month ago, the response to a single injection is 5 letters. If the loss occurred 2 months ago, there was a gain of just 1.7 letters. Monthly monitoring is most important,” she said.

She said that in relation to anti-VEGF and atrophy, RPE damage is pre-existing in most elderly patients and CNV causes large RPE defects. However, anti-VEGF therapy does not increase RPE atrophy, and on the contrary large defects often close or become smaller. “There is significant plasticity of the RPE in AMD”.

She concluded that neovascular AMD is not a self-limiting disease, but a chronic condition that does not go away and requires constant monitoring. “Re-treatment indications need to be identified, retinal thickening may not be enough.”