The monoclonal antibodies cetuximab, rituximab and ipilimumab differ in their degree of humanisation. The correct order from most murine content to least murine content is:
- A Ipilimumab, rituximab, cetuximab
- B Cetuximab, rituximab, ipilimumab ✓
- C Rituximab, cetuximab, ipilimumab
- D All three have identical murine content
Correct answer: B. Cetuximab, rituximab, ipilimumab
Explanation
The suffix encodes origin: omab indicates fully murine, ximab indicates chimeric (about 65 percent human), zumab indicates humanised (about 90 percent human), and mumab indicates fully human. Cetuximab is chimeric mouse-human, rituximab is also chimeric, and ipilimumab is fully human. Wait, both cetuximab and rituximab are chimeric, so among these three the murine fraction of cetuximab and rituximab is equal and greater than that of ipilimumab. The intended teaching point is the naming system itself: ximab means chimeric and mumab means fully human.
Reference: Katzung's Basic and Clinical Pharmacology, 16th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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