Last reviewed 2026-04-23 · How we verify

Pembrolizumab biosimilar

This biosimilar blocks PD-1 on immune cells to restore anti-tumor immunity by preventing tumor cells from suppressing T-cell responses.

This biosimilar blocks PD-1 on immune cells to restore anti-tumor immunity by preventing tumor cells from suppressing T-cell responses. Used for Metastatic melanoma, Non-small cell lung cancer (NSCLC), Head and neck squamous cell carcinoma.

At a glance

Mechanism of action

Pembrolizumab is a monoclonal antibody that binds to programmed death receptor-1 (PD-1) on T cells, blocking interaction with PD-L1 and PD-L2 ligands expressed by tumor cells. This blockade releases the brakes on the immune system, allowing T cells to recognize and attack cancer cells. As a biosimilar, it is designed to have equivalent efficacy and safety to the reference pembrolizumab product.

Approved indications

• Metastatic melanoma
• Non-small cell lung cancer (NSCLC)
• Head and neck squamous cell carcinoma
• Hodgkin lymphoma
• Urothelial carcinoma
• Gastric or gastroesophageal junction adenocarcinoma

Common side effects

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

Key clinical trials

• Pembrolizumab Plus CA-4948 for the Treatment of Patients With Progressive Metastatic Urothelial Cancer Despite Prior Immunotherapy (PHASE1)
• Combining Immunotherapy and Radiation Therapy to Help Patients Avoid Bladder Removal After Treatment Shrinks Muscle Invasive Bladder Cancer, BRIGHT Trial (PHASE2)
• 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)
• Testing the Addition of an Anti-cancer Drug, Pembrolizumab, to the Usual Intravesical Chemotherapy Treatment (Gemcitabine) for the Treatment of BCG-Unresponsive Non-muscle Invasive Bladder Cancer (PHASE2)
• Testing the Addition of Tazemetostat to the Immunotherapy Drug, Pembrolizumab (MK-3475), in Advanced Urothelial Carcinoma (PHASE1, PHASE2)
• A Study to Compare the Administration of Pembrolizumab After Surgery Versus Administration Both Before and After Surgery for High-Risk Melanoma (PHASE2)
• Testing the Addition of an Antiangiogenic Drug (Bevacizumab) to Chemotherapy (Carboplatin and Paclitaxel) Combined With Immunotherapy (Pembrolizumab) for pMMR, TP53 Mutated Endometrial Cancer (PHASE3)
• Testing the Addition of the Immunotherapy Drug, Pembrolizumab, to Radiation Therapy Compared to the Usual Chemotherapy Treatment During Radiation Therapy for Bladder Cancer, PARRC Trial (PHASE2)

Primary sources

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