Last reviewed 2026-04-23 · How we verify

Pembrolizumab SC

Pembrolizumab is a monoclonal antibody that blocks PD-1 on immune cells, allowing them to recognize and attack cancer cells.

Pembrolizumab is a monoclonal antibody that blocks PD-1 on immune cells, allowing them to recognize and attack cancer cells. Used for Metastatic non-small cell lung cancer (NSCLC), Melanoma, Head and neck squamous cell carcinoma.

At a glance

Mechanism of action

Pembrolizumab binds to programmed death receptor 1 (PD-1) on T cells, preventing interaction with PD-L1 and PD-L2 ligands expressed on tumor cells and immune cells. This blockade releases the brakes on the immune system, restoring T-cell proliferation, activation, and anti-tumor function. The subcutaneous (SC) formulation provides an alternative to intravenous administration with improved patient convenience.

Approved indications

• Metastatic non-small cell lung cancer (NSCLC)
• Melanoma
• Head and neck squamous cell carcinoma
• Hodgkin lymphoma
• Urothelial carcinoma
• Microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) solid tumors

Common side effects

• Fatigue
• Decreased appetite
• Nausea
• Diarrhea
• Immune-mediated pneumonitis
• Immune-mediated colitis
• Immune-mediated hepatitis
• Immune-mediated thyroiditis
• Rash

Key clinical trials

• BLAST MRD AML-2: BLockade of PD-1 Added to Standard Therapy to Target Measurable Residual Disease in Acute Myeloid Leukemia 2- A Randomized Phase 2 Study of Anti-PD-1 Pembrolizumab in Combination With Azacitidine and Venetoclax as Frontline Therapy in Unfit Patients With Acute Myeloid Leukemia (PHASE2)
• Physician/Patient Choice of Either High-Dose Recombinant Interferon Alfa-2B or Ipilimumab, Versus Pembrolizumab in Treating Patients With Stage III-IV High Risk Melanoma That Has Been Removed by Surgery (PHASE3)
• A Study to Evaluate the Bioavailability of Pembrolizumab (MK-3475) Via Subcutaneous (SC) Injection of Pembrolizumab Formulated With Berahyaluronidase Alfa (MK-5180) [MK-3475A] In Advanced Solid Tumors (MK-3475A-C18) (PHASE1)
• Pembrolizumab and Recombinant Interleukin-12 in Treating Patients With Solid Tumors (PHASE1)
• A Study Evaluating Whether Pembrolizumab Alone or in Combination With CMP-001 Improves Efficacy of Treatment in Patients With Operable Melanoma (PHASE2)
• APL-2 and Pembrolizumab Versus APL-2, Pembrolizumab and Bevacizumab Versus Bevacizumab Alone for the Treatment of Recurrent Ovarian, Fallopian Tube, or Primary Peritoneal Cancer and Malignant Effusion (PHASE2)
• A Clinical Study of Calderasib (MK-1084) and Other Treatments for Participants With Non-Small Cell Lung Cancer (MK-1084-007/KANDLELIT-007) (PHASE3)
• Study of STK-012 Alone and With Other Treatments in Patients With Advanced Lung Cancer and Other Cancers (PHASE1, PHASE2)

Primary sources

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