Last reviewed 2026-04-20 · How we verify

Zynyz (RETIFANLIMAB)

Zynyz works by blocking the PD-1 receptor on immune cells, allowing them to recognize and attack cancer cells.

Zynyz (Retifanlimab) is a programmed death receptor-1 blocking antibody developed by Incyte Corp, targeting programmed cell death protein 1. It is a monoclonal antibody that works by blocking the PD-1 receptor, allowing the immune system to attack cancer cells. Zynyz is FDA-approved for the treatment of Merkel cell carcinoma and is currently patented by Incyte Corp. Key safety considerations include immune-mediated adverse reactions and potential liver damage. As a relatively new medication, there is limited long-term safety data available.

At a glance

Mechanism of action

Binding of the PD-1 ligands, PD-L1 and PD-L2, to the PD-1 receptor found on cells, inhibits T-cell proliferation and cytokine production. Upregulation of PD-1 ligands occurs in some tumors, and signaling through this pathway can contribute to inhibition of active T-cell immune surveillance of tumors.Retifanlimab-dlwr binds to the PD-1 receptor, blocks interaction with its ligands PD-L1 and PD-L2, and potentiates T-cell activity.

Approved indications

• Merkel cell carcinoma

Common side effects

• Fatigue
• Musculoskeletal pain
• Pruritus
• Diarrhea
• Rash
• Pyrexia
• Nausea
• Serious adverse reactions
• Arrhythmia
• Pneumonitis
• Permanent discontinuation of ZYNYZ
• Dosage interruptions

Key clinical trials

• Study of Retinfanlimab in Combination With INCAGN02385 and INCAGN02390 as First-Line Treatment in Participants With PD-L1-Positive (CPS ≥ 1) Recurrent/Metastatic Squamous Cell Carcinoma of the Head and Neck (PHASE2)
• Combination Study of SV-BR-1-GM With Retifanlimab (PHASE1,PHASE2)
• A Study to Evaluate INCB177054 in Participants With Select Advanced or Metastatic Solid Tumors (PHASE1,PHASE2)
• Short-term Fasting Prior to PD-1/PD-L1 Inhibitor Therapy for of Advanced or Metastatic Skin Malignancy (PHASE1)
• ASTX727 & Retifanlimab-dlwr for Advanced Merkel Cell After Progression on Anti-PD-(L)1 (PHASE1,PHASE2)
• A Study to Evaluate INCB161734 in Participants With Advanced or Metastatic Solid Tumors With KRAS G12D Mutation (PHASE1)
• Retifanlimab With or Without Difluoromethylornithine for the Treatment of Progressive High Grade Gliomas (PHASE1,PHASE2)
• Neoantigen-based Personalized DNA Vaccine With Retifanlimab PD-1 Blockade Therapy in Patients With Newly Diagnosed, Unmethylated Glioblastoma (PHASE1)

Patents

Primary sources

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