Programmed death-1 receptor (PD-1)/its ligand (PD-L1) antibodies have changed 
the landscape in oncology in 2013. The most mature results have been obtained in 
advanced melanoma patients. They indicate important response rates and high 
quality responses or prolonged duration. Also in renal cancer and in lung cancer 
remarkable activity has been demonstrated. Thus it is clear that these 
antibodies have a very broad potential and trials in many tumour types are being 
initiated. Breaking tolerance at the tumour site is a potent phenomenon and the 
potential for synergy with other checkpoint inhibitors such as ipilimumab have 
also been demonstrated in 2013. Long term tumour control now seems achievable 
and thus the concept of a clinical cure is emerging by modulation of the immune 
system. These antibodies bring immunotherapy to the forefront and indicate that 
immune-modulation will be a key component of therapeutic strategies from now on. 
Because of all these reasons PD-1/PD-L1 antibodies are considered 'drug of the 
year'.