Pharmacogenomic Study on Anti-VEGF Medicine in Treatment of Macular Neovascular Diseases

Research Background

Macular neovascular disease, is a group of diseases with subfoveal choroidal neovascularization, including age-related macular degeneration (AMD), polypoidal choroidal vasculopathy (PCV), pathological myopia (PM) and etc. Due to the high permeability of immature blood vessel wall, consequent bleeding, and scarring，macular neovascularization often leads to severe vision loss. It has become the focus of World Health Organization's blindness- prevention cause [1]. Currently, the vascular endothelial growth factor (VEGF) has been widely recognized as an important promoter for neovascularization. And a series of large-scale clinical studies revealed that anti- VEGF drug is the only effective way for macular neovascular disease [2], Anti-VEGF drug has been awarded as one of the top ten scientific and technological progress by Nature magazine.

Conbercept is an anti-VEGF drug developed independently by Chinese researchers in recent years, it competitively prevents the binding of VEGF to its receptor and inhibits the downstream pathway activation, and has a higher binding affinity to VEGFA than other widely used anti-VEGF drugs. Many multicenter double blind random controlled study showed that conbercept has good efficacy and safety in treating macular neovascular diseases. In 2013, conbercept has been approved by the State Food and Drug Regulatory Administration of China and now has been widely used and recognized.

Clinical trial results showed that the conbercept has good efficacy and safety in treating macular neovascular diseases [3], but the exact therapeutic regimen and the efficacy in the real world still needs to be further studied, the reasons are as follows:

1. The efficacy and safety data of conbercept are collected from rigorous random controlled trials (RCT), it cannot fully reflect the clinical application of conbercept in the real world. Therefore, the knowledge of the therapeutic regimen, safety and efficacy of conbercept is still limited.
2. Conbercept has been approved for wet-AMD only, but in clinical practice, some doctors applied other "off-label use" of conbercept. These "off-label use" has become a common phenomenon all over the world for the instruction book of drugs usually lag behind scientific researches. There is no specific law or regulatory document of drug off-label use in China until now.
3. Anti-VEGF drugs are expensive and often require multiple treatments, besides, some patients have poor or even no response to the drugs. This resulted enormous waste of medical resources. So, how to accurately find out those patients who have good response, how to develop individualized therapeutic regimen, and the response of patients in the real world need to be urgently investigated in the aspect of pharmacogenomics, and pharmacometabolomics.