Within the proposed single arm multicenter phase-II trial it is intended to investigate the
feasi-bility of adding Avelumab to FOLFIRI plus Cetuximab after 4 cycles (2 months) of
treatment with FOLFIRI plus Cetuximab. After 4 more cycles of FOLFIRI plus Cetuximab plus
Avelumab the treatment will be de-escalated to Avelumab as a maintenance concept until
progression of the disease according to RECIST 1.1 has occurred.