A 70-year-old woman with osteoporosis is started on denosumab. The mechanism of action of denosumab is:
- A Binding to and inhibiting RANK ligand, preventing osteoclast formation, function, and survival ✓
- B Incorporating into bone mineral and inducing osteoclast apoptosis via mevalonate pathway inhibition
- C Activating osteoblast Wnt signaling pathway by neutralizing sclerostin
- D Acting as a selective estrogen receptor modulator to reduce bone resorption
Correct answer: A. Binding to and inhibiting RANK ligand, preventing osteoclast formation, function, and survival
Explanation
Denosumab is a fully human monoclonal antibody against RANKL. By binding RANKL, it prevents RANKL from activating RANK on osteoclast precursors, thereby inhibiting osteoclast formation, function, and survival. Option B describes bisphosphonates. Option C describes romosozumab. Option D describes raloxifene.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.