Ustekinumab, used in moderate-to-severe plaque psoriasis, exerts its effect by binding:
- A The p19 subunit of IL-23
- B IL-17A
- C The p40 subunit shared by IL-12 and IL-23 ✓
- D Soluble TNF-alpha receptors
Correct answer: C. The p40 subunit shared by IL-12 and IL-23
Explanation
Ustekinumab is a human monoclonal antibody against the p40 subunit common to both IL-12 and IL-23, thereby blocking Th1 and Th17 pathways simultaneously. Agents targeting IL-17C include secukinumab and ixekizumab, while tildrakizumab and guselkumab target the p19 subunit unique to IL-23. Etanercept is the soluble TNF receptor fusion protein. This subunit specificity is a frequently examined distinction among biologics.
Reference: Katzung's Basic and Clinical Pharmacology, 16th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.