Cilengitide "promotes cancer growth"

Cancer Research UK-funded scientists have found evidence to suggest that low doses of Merck KGaA's cilengitide in laboratory studies can have the  opposite effect to that expected and promote cancer growth, according to  research published in Nature Medicine. The German drugmaker's  investigational integrin inhibitor recently entered mid-stage testing  (Marketletter March 23).

Lead study author, Andy Reynolds, said: "our study revealed a previously  unknown mechanism through which drugs such as cilengitide behave. It  showed that, while higher concentrations of cilengitide can block  angiogenesis, lower concentrations can actually stimulate the supply of  blood to the tumor and can promote its growth. These results may explain  why initial results from early-stage clinical trials have not been as  promising as hoped."

Commenting on the findings, Merck KGaA spokesperson Phyllis Carter said:  "the data presented in this paper are of interest to the overall debate  as to the mode of action of integrin inhibitors. However, it does not  reflect previous findings in other preclinical models in vivo or in  vitro, either as single agent or in combination. Even more important the  observations of Reynolds et al in preclinical models have not been  reflected in clinical settings."