Genes affect anti-VEGF response

This prospective study found that vascular endothelial growth factor (VEGF) C-634G polymorphism (CC genotype) is a genetic risk factor for diabetic macular edema (DME), and its presence is associated with significantly better visual outcomes following bevacizumab (Avastin) treatment.

The authors examined the association between VEGF gene polymorphisms and anti-VEGF treatment outcomes in 392 diabetic patients‑212 with diabetic retinopathy and 180 without retinopathy.

CC genotype was significantly prevalent among DME patients (P  =  0.019). Significant higher serum levels of VEGF were detected in diabetic retinopathy and DME patients with CC genotype (P  =  0.02). After bevacizumab treatment, individuals with genotypes CG and GG showed a decreased chance of positive treatment outcomes compared with CC genotype (P  <  0.001).

To the authors’ knowledge, this is the first report of a correlation between genetic profile and response to anti-VEGF therapy in Egyptian patients with DME. They believe this VEGF C-634G polymorphism could explain the variability in the response to bevacizumab treatment in DME patients.

They write that this finding is particularly helpful for individualizing treatment options based on a patient's genetic profile, allowing a better choice of medication, improving outcomes and eliminating trial-and-error treatment.