II. History
- Initially targeted to CD20 on immune cells to treat Lymphoma and Leukemia
- Lead to immunosuppressive use in Autoimmune Conditions such as Rheumatoid Arthritis
III. Mechanism
- Targeted to solid tumors (e.g. Breast Cancer, Lung Cancer and Colon Cancer)
- Bind extracellular Ligands and receptor binding sites
- Monoclonal antibodies act at targeted cells via oncogene downregulation or tumor cell flagging for destruction
IV. Pharmacokinetics
- Large molecules (150,000 Da)
- Water-soluble
- Proteins are denatured by intestinal acids (therefore must be used intravenously)
- No hepatic metabolism (therefore no significant Drug Interactions)
- Antibodies have long half-lives of days to weeks
V. Disadvantages
- Very expensive (typically upwards of $10,000 per course)
VI. Medications: Surface Antigen Targets
-
General
- Monoclonal Antibody targets are specific cell surface receptors
- Target: CD20
- See CD20 Monoclonal Antibody
- Rituximab (Rituxan): Used in Non-Hodgkin's Lymphoma and Rheumatoid Arthritis
- Ibritumomab tiuxetan (Zevalin): Used Non-Hodgkin's Lymphoma
- Tositumomab (Bexxar): Used in Non-Hodgkin's Lymphoma
- Target: CD22
- See CD22 Monoclonal Antibody
- CD22 is a B Cell lectin and adhesion molecule
- Moxetumomab pasudotox-tdfk (Lumoxiti)
- Conjugated Monoclonal Antibody that delivers the cytotoxic drug Pseudomonas exotoxin A to cancer cells
- Used in Hairy Cell Leukemia
- Risks of Hemolytic Uremic Syndrome, capillary leak syndrome, renal toxicity, Electrolyte abnormalities
- Inotuzumab Ozogamicin (Besponsa)
- Conjugated Monoclonal Antibody that delivers the cytotoxic drug calicheamicin to cancer cells
- Used against B Cell precursors in Acute Lymphoblastic Leukemia
- Risks of hepatotoxicity and veno-occlusive disease
- Target: CD30
- See CD30 Monoclonal Antibody
- CD30 is a Tumor Necrosis Factor (TNF) receptor found on the surface of White Blood Cells
- CD30 is overexpressed in hematopoietic malignancies
- Brentuximab vedotin (Adcetris)
- Conjugated Monoclonal Antibody that delivers the cytotoxic drug monomethyl auristatin E (MMAE) to cancer cells
- Used in Hodgkins Lymphoma
- Target: CD33
- See CD33 Monoclonal Antibody
- CD33 is a small Protein on the surface of myeloid cells and Monocyte-Macrophage precursors
- CD33 interacts with SHP-1 and SHP-2 Protein kinases for intracellular signaling
- Gemtuzumab ozogamacin (Mylotarg)
- Conjugated Monoclonal Antibody that delivers the cytotoxic drug calicheamicin to cancer cells
- Used in Acute Myelogenous Leukemia (AML)
- Target: CD38
- Target: CD52
- See CD52 Monoclonal Antibody
- Alemtuzumab: Restricted use for CLL (Campath) and Multiple Sclerosis (Lemtrada)
- Target: CCR4
- See CCR4 Monoclonal Antibody
- CCR4 is a cell surface receptor that binds Cytokines (CCL2, CCL4, CCL5, CCL17 and CCL22)
- CCR4 binding by Cytokine triggers chemotaxis of inflammatory cells (e.g. Natural Killer Cells)
- Mogamulizumab-kpkc (Poteligeo): Used in Cutaneous T Cell Lymphoma
- Target: GD2
- See GD2 Monoclonal Antibody
- GD2 is the cell surface receptor Glycolipid disialoganglioside
- Dinutuximab (Unituxin): Used in Neuroblastoma
VII. Medications: Tyrosine Kinase Targets
- See Tyrosine Kinase
- See Small Molecule Inhibitor-Mediated Chemotherapy
- Target: Epidermal Growth Factor Receptor (EGFR, HER1)
- See EGFR Monoclonal Antibody
- See EGFR Inhibitor
- Cetuximab (Erbitux): Used in Colon Cancer and head and neck tumors
- Panitumumab (Vectibix): Used in Colon Cancer
- EGFR agents have been effective in metastatic Colorectal Cancer (without RAS mutation)
- Adverse effects related to EGFR targeted on cancer cells, but also present in skin and GI Tract
- Adverse effects include acne, Hypomagnesemia
- Dermatitis often is an indicator that the EGFR Inhibitor is working
- Diarrhea occurs in 50% of patients on EGFR Inhibitors
- Target: Vascular Endothelial Growth Factor (VEGF)
- See VEGFR Monoclonal Antibody
- See VEGFR Inhibitor
- VEGF Inhibitors suppress Angiogenesis (e.g. Avastin)
- Adverse effects include Bleeding, Thrombosis and Hypertension
- Bevacizumab (Avastin): Used in Colon Cancer and Non-Small Cell Lung Cancer
- Ramucirumab (Cyramza): Used in Colon Cancer, Hepatocellular Carcinoma and Gastric Cancer
- Target: HER2-neu
- See Anti-HER2 Monoclonal Antibody
- Adverse effects include cardiotoxicity, Diarrhea
- Pertuzamab (Perjeta)
- Trastuzumab (Herceptin): Used in Breast Cancer (where HER2-neu is overexpressed)
- Trastuzumab has been very effective in HER2 positive Breast Cancer
- Ado-Trastuzumab Emtansine (Kadcyla)
- Trastuzumab is conjugated to the cytotoxic agent emtansine (DM1), a microtubule inhibitor
- Delivers cytotoxic DM1 to HER2 positive cells (e.g. Breast Cancer)
- Risk of Trastuzumab adverse effects, as well as hepatotoxicity, bleeding
VIII. Medications: Immune Checkpoint Inhibitors
- See Immune Checkpoint Inhibitor
- Target: Cytotoxic T Lymphocyte associated-4 (CTLA-4)
- Target: Programmed Cell Death Protein 1 (PD-1)
- Target: Programmed death Ligand-1 (PDL-1)
IX. References
- Olson (2020) Clinical Pharmacology, Medmaster, Miami, Fl, p. 131-5
- Adams (2005) Nat Biotechnol 23:1147-57 [PubMed]
- Smith (2021) Am Fam Physician 103(3): 155-63 [PubMed]