What FDA‑approved monoclonal antibody agents are used for cancer therapy and what are their recommended dosing regimens?

FDA-Approved Monoclonal Antibodies for Cancer Therapy

Multiple FDA-approved monoclonal antibodies are available for cancer therapy, with immune checkpoint inhibitors representing the most widely used class across solid tumors and hematologic malignancies.

Immune Checkpoint Inhibitors

Anti-PD-1 Antibodies

Nivolumab 1:

• Dosing: 3 mg/kg IV every 2 weeks OR 240 mg IV every 2 weeks OR 480 mg IV every 4 weeks 2, 3
• Indications: Advanced melanoma, NSCLC, RCC, Hodgkin lymphoma, urothelial carcinoma, MSI-H/dMMR cancers 1
• Mechanism: Engineered IgG4 mAb blocking PD-1 with negligible ADCC 1

Pembrolizumab 1:

• Dosing: 200 mg IV every 3 weeks OR 400 mg IV every 6 weeks 2, 3
• Alternative dosing from trials: 2 mg/kg every 3 weeks or 10 mg/kg every 2-3 weeks 3
• Indications: Advanced melanoma, NSCLC, MSI-H/dMMR cancers (tissue-agnostic approval) 1
• Mechanism: Engineered IgG4 mAb blocking PD-1 with negligible ADCC 1

Anti-PD-L1 Antibodies

Atezolizumab 1:

• Indications: NSCLC, urothelial carcinoma
• Mechanism: Engineered IgG1 mAb with Fc modifications eliminating ADCC 1

Durvalumab 1, 4:

• Dosing: 1500 mg IV every 3 weeks (when combined with chemotherapy) 4
• Indications: NSCLC, urothelial carcinoma
• Mechanism: Engineered IgG1 mAb with Fc modifications eliminating ADCC 1

Avelumab 1:

• Indications: Merkel cell carcinoma, urothelial carcinoma
• Mechanism: Wildtype IgG1 framework with intact ADCC 1

Anti-CTLA-4 Antibody

Ipilimumab 1, 5:

• Metastatic disease dosing: 3 mg/kg IV every 3 weeks for 4 doses 3, 5, 6
• Adjuvant high-dose regimen: 10 mg/kg IV every 3 weeks for 4 doses, then 10 mg/kg every 12 weeks for up to 3 years 5
• Indications: Advanced melanoma (first ICI approved in 2011) 1
• Mechanism: Fully human IgG1 mAb blocking CTLA-4 1, 6

Combination Regimens

Nivolumab + Ipilimumab 1, 2, 7:

• Dosing: Nivolumab 1 mg/kg + ipilimumab 3 mg/kg IV every 3 weeks for 4 doses, followed by nivolumab 3 mg/kg every 2 weeks OR nivolumab 240 mg every 2 weeks OR 480 mg every 4 weeks 2, 3
• Indications: Advanced melanoma (approved 2015), intermediate/poor-risk aRCC (approved 2018) 1, 7

Nivolumab + Relatlimab 2:

• Dosing: Relatlimab 160 mg + nivolumab 480 mg IV every 4 weeks 2
• Indications: Advanced melanoma

Pembrolizumab + Axitinib 7:

• Approval: First-line aRCC (approved April 2019)

Avelumab + Axitinib 7:

• Approval: First-line aRCC (approved May 2019)

Hematologic Malignancy-Specific Antibodies

Rituximab 8, 9, 10:

• Dosing: 375 mg/m² IV 9
• Indications: B-cell NHL, CLL, follicular lymphoma, diffuse large B-cell lymphoma
• Mechanism: Anti-CD20 antibody (first FDA-approved mAb for cancer in 1997) 10

Alemtuzumab 8, 9:

• Dosing: 30 mg IV three times weekly after initial dose escalation 9
• Indications: B-cell CLL (after alkylating agent and fludarabine failure), some T-cell neoplasias
• Mechanism: Anti-CD52 humanized mAb 8

Gemtuzumab ozogamicin 8, 9:

• Dosing: 9 mg/m² IV at 2-week intervals for 2 doses 9
• Indications: CD33-positive AML in first relapse (age ≥60 years)
• Mechanism: Anti-CD33 mAb conjugated with calicheamicin 8

Solid Tumor-Specific Antibodies

Trastuzumab (Herceptin) 11:

• Indications: HER2-positive breast cancer
• Mechanism: Blocks HER2 growth factor receptor

Bevacizumab (Avastin) 11:

• Indications: Colorectal cancer, NSCLC
• Mechanism: Anti-VEGF antibody inhibiting angiogenesis

Cetuximab (Erbitux) 11:

• Indications: Colorectal cancer, head and neck cancer
• Mechanism: Anti-EGFR antibody

Panitumumab (Vectibix) 11:

• Indications: Colorectal cancer
• Mechanism: Anti-EGFR antibody

Critical Dosing Considerations

Treatment Duration

• Anti-PD-1 agents: Continue until disease progression or unacceptable toxicity 3, 12
• Most responses develop within 6 months, but delayed responses can occur 3
• Responses are highly durable and often persist years beyond treatment discontinuation 3
• Limited data exists for treatment beyond 2 years 3

Neoadjuvant Regimens (Melanoma)

Pembrolizumab 13:

• 200 mg IV every 3 weeks for 3 doses preoperatively, followed by 15 additional doses postoperatively
• Improved 2-year event-free survival: 72% vs 49% (adjuvant-only) 13

Nivolumab 4:

• 360 mg IV with platinum-doublet chemotherapy every 3 weeks for up to 4 cycles (NSCLC)
• Can continue as single-agent adjuvant therapy post-surgery 4

Important Safety Considerations

Immune-related adverse events (irAEs) occur with all checkpoint inhibitors 1:

• Incidence: Up to 90% any-grade with single-agent therapy; <75% with anti-CTLA-4; ≤30% with anti-PD-1 1
• Treatment-related deaths: Up to 2% of patients 1
• Management: Early recognition and prompt intervention with immunosuppression (typically corticosteroids) 1
• Delayed onset and prolonged duration compared to chemotherapy toxicities 1

Dose-dependent toxicity: Ipilimumab 10 mg/kg has threefold higher risk of irAEs versus 3 mg/kg 5

Common irAEs: Skin, gut, endocrine, lung, musculoskeletal 1

Rare but serious irAEs: Cardiovascular, hematologic, renal, neurologic, ophthalmologic 1