A 34-year-old woman comes to the physician for a follow-up visit. She was diagnosed with rheumatoid arthritis 3 months ago and started on methotrexate therapy. Despite treatment, she continues to have several hours of morning stiffness daily and frequently awakens at night due to joint pain. Physical examination shows swelling and tenderness in the joints of her hands and wrists. Etanercept is subsequently added to her treatment regimen. This medication is best characterized as which of the following?

Question

A 34-year-old woman comes to the physician for a follow-up visit.  She was diagnosed with rheumatoid arthritis 3 months ago and started on methotrexate therapy.  Despite treatment, she continues to have several hours of morning stiffness daily and frequently awakens at night due to joint pain.  Physical examination shows swelling and tenderness in the joints of her hands and wrists.  Etanercept is subsequently added to her treatment regimen.  This medication is best characterized as which of the following?

Quizplus · Accepted Answer

11ec160b_37a8_98c7_9249_d554cc9a3e63_MD0001_00 Etanercept is a tumor necrosis factor-alpha (TNF-α) inhibitor added to methotrexate to treat moderate-to- severe rheumatoid arthritis in patients who have failed methotrexate alone. It is a fusion protein linking a soluble TNF-α receptor to the Fc component of human immunoglobulin G1 (IgG1). Etanercept reduces the biological activity of TNF-α by acting as a decoy receptor: the TNF-α receptor component acts like a sponge to bind TNF-α and keep it away from functional TNF-α receptors, while the Fc component stabilizes the complex. Pharmaceutical companies provide the prefix of the names for biological agents; the suffix indicates whether the medication is a monoclonal antibody (mab), a receptor molecule (cept), or a kinase inhibitor (nib). Monoclonal antibodies, which are the largest group of biological agents, also include in their names the type of target (eg, bacterial or immune system) and their origin (eg, human or mouse). (Choice A) Rituximab (Ri-tu-xi-mab) is a chimeric monoclonal antibody targeted against CD20, a cell receptor found on the surface of B cells. It is used to treat CD20+ non-Hodgkin's lymphomas and other diseases related to excessive B-cell function. (Choice B) Infliximab (Inf-li-xi-mab) is a chimeric monoclonal antibody targeted against TNF-α. It is used in the treatment of a number of autoimmune diseases (eg, rheumatoid arthritis and Crohn's disease). (Choice C) Certolizumab pegol (Certo-li-zu-mab) is a pegylated (pegol) humanized monoclonal antibody that targets TNF-α. It lacks the Fc region, which helps minimizes complement activation and cell-mediated cytotoxicity that can occur with other anti-TNF-α medications that contain Fc domains. (Choice D) Imatinib (Imati-nib) mesylate is used to treat specific cancers, including Philadelphia chromosome-positive chronic myelogenous leukemia and kit-positive gastrointestinal stromal tumors. It is an example of a small-molecule tyrosine kinase receptor inhibitor. Educational objective: The suffix of a biological agent indicates whether a medication is a monoclonal antibody (mab), a receptor molecule (cept), or a kinase inhibitor (nib). Monoclonal antibodies also include in their names the type of target (eg, bacterial or immune system) and their origin (eg, human or mouse).

A 34-Year-Old Woman Comes to the Physician for a Follow-Up