sentence: In these studies , the molecule showed a favorable toxicity profile and clinical effects.31 36 37 Therefore a clinical trial in patients with pretreated advanced metastatic colorectal and pancreatic cancer was initiated ( OPERA trial , Keynote-559 , NCT03168139 , EUDRACT 2016-003657-15 ) , combining the anti-CXCL12 spiegelmer NOX-A12 with pembrolizumab .