Retifanlimab-dlwr is an anti-programmed death receptor-1 (PD-1) monoclonal antibody that binds to PD-1, a checkpoint inhibitor control, blocking its engagement. PD-1 is a negative regulator of T-cell activation and proliferation, meaning PD-1 engagement will turn the immune response off, essentially acting as a brake.
The drug is indicated for the treatment of adult patients with metastatic or recurrent locally advanced Merkel cell carcinoma.