A 55-year-old man with HIV is failing his protease inhibitor-based regimen. Genotypic resistance testing confirms multiple protease inhibitor mutations but no INSTI resistance. The physician decides to switch to a regimen containing dolutegravir. Dolutegravir belongs to which class and acts at which step of the HIV life cycle?
- A INSTI; blocks integration of viral DNA into host genome ✓
- B NNRTI; binds reverse transcriptase at allosteric site
- C NRTI; inhibits reverse transcription
- D Entry inhibitor; blocks gp41 mediated fusion
Correct answer: A. INSTI; blocks integration of viral DNA into host genome
Explanation
Dolutegravir is an integrase strand transfer inhibitor (INSTI). It blocks the HIV integrase enzyme, preventing integration of viral DNA into the host cell genome. This is a distinct mechanism from NRTIs (chain terminators), NNRTIs (allosteric RT inhibitors), and entry inhibitors such as enfuvirtide (gp41 blocker) or maraviroc (CCR5 antagonist).
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.