(2022 Clin Cancer Res 28: 57-70) reported encouraging results of the initial clinical study combining the ILT4 antagonist mAb MK-4830 with pembrolizumab. Doses of CDX-585 up to 60 mg/kg were well tolerated in cynomolgus macaques and displayed a favorable pharmacokinetic profile. Together these data demonstrate that CDX-585 effectively combines PD-1 and ILT4 blockade into one molecule with favorable biophysical and functional characteristics supporting the initiation of a dose-escalation clinical trial in patients with advanced solid tumors.