Table 3.

Clinical investigations regarding inhibition of FAP

FAP inhibitor	FAP inhibitor type	Study type	Sample size	Results	Refs
Sibrotuzumab	a humanized version of the murine anti-FAP mAb F19	Phase I open-label dose-escalation trial	20 Patients with CRC	No objective tumor response	[118]
unconjugated sibrotuzumab (BIBH 1)	a humanized version of the murine anti-FAP mAb F19	Phase I open-label, uncontrolled trial	25 Patients with metastatic CRC	Minimal clinical activity	[119]
Val‑boroPro (Talabostat)	inhibitor of dipeptidyl peptidases	phase II clinical trial	28 Patients with metastatic CRC	Minimal clinical activity	[110]

mAb Monoclonal Antibody