CD274 and neoplasm: However, the study did not reach the primary endpoint of tumor shrinkage between vopratelimab plus pimivalimab and pimivalimab monotherapy groups.307 Alomfilimab depleted ICOShigh Tregs, had monotherapy anti-tumor efficacy, and improved anti-PD-L1 efficacy in a pre-clinical study.308 According to a preliminary report there were 5 OR cases out of 103 patients in a phase I/II trial testing alomfilimab ± atezolizumab.309 In summary, ICOS drug development is still challenging.