The impact of molecular targets in cancer drug development: major hurdles and future strategies

The last decades were characterized by enormous technological advances resulting in a better understanding of disease pathologies and improvement of treatment strategies. The development of targeted drugs, whose beginning can be traced back to Paul Ehrlich's theory of the 'magic bullet' approximately 100 years ago, is today widely appraised as a promising strategy to combat benign, as well as malignant, diseases. Over 40 years after US President Nixon declared the 'war on cancer', treatment outcome, especially of solid tumors in the advanced stages of disease, still lies far behind expectations. In this perspective article, the authors discuss the recent development of targeted cancer drugs and identify major hurdles. The authors further highlight future strategies that might improve and accelerate the drug-development process.