The study confirms our hypothesis that targeting PlGF is safe and different from anti-VEGF(R) therapies which are known to cause a number of side effects, including cardiotoxicity, heart failure, and hypertension (Eskens and Verweij, 2006; Force et al, 2007; Verheul and Pinedo, 2007; Eremina et al, 2008). This evidence concerns the gene PGF and heart failure.