Anti-VEGFs go head-to-head

Clinical doses of Avastin (bevacizumab; Genentech) and Lucentis (ranibizumab; Novartis) are equally effective in neutralizing vascular endothelial growth factor (VEGF), while Macugen (pegaptanib; Pfizer) has no effect, according to a study published online ahead of print by the Journal of Investigative Ophthalmology.

Alexa K. Klettner of the Universitatsklinikum Schleswig-Holstein, Germany and colleagues compared the efficacy of clinically significant doses of the three VEGF-antagonists in an in vitro system.

Both bevacizumab and ranibizumab were found to neutralize VEGF entirely for six hours, and significantly for up to 16 hours. When the doses were diluted, bevacizumab became ineffective at a concentration of 975 ng/ml (clinical dose=0.25 mg/ml); ranibizumab continued to neutralize VEGF at a concentration of 120 ng/ml (clinical dose=0.125 mg/ml). Pegaptanib was not found to neutralize VEGF at all.

The researchers concluded that, while pegaptanib was not effective against VEGF, in an in vitro system both bevacizumab and ranibizumab are able to neutralize VEGF at levels lower than clinical dose.