We have identified a series of BPR1R compounds as highly selective CSF1R inhibitors with excellent oral bioavailability. In vivo, oral administration of BPR1R compounds delayed murine colon tumor growthreversed the immunosuppressive TME with increased M1/M2 ratio. The US & PCT patent application including more than 160 novel compounds was filed in April 20, 2020. Several potential compounds are undergoing candidate assessment for further preclinical studies.