Comparison: Protease Inhibitors vs Integrase Inhibitors- BPharm, MBBS, BDS, Nursing exams
Comparison: Protease Inhibitors vs Integrase Inhibitors
| Feature | Protease Inhibitors (PIs) | Integrase Inhibitors (INSTIs) |
|---|---|---|
| Mechanism of Action | Inhibit HIV protease enzyme → prevents cleavage of viral polyproteins | Inhibit HIV integrase enzyme → prevents integration of viral DNA |
| Target Step in Lifecycle | Late phase – virus maturation | Early phase – integration of viral DNA into host genome |
| Examples | Lopinavir, Ritonavir, Atazanavir, Darunavir | Raltegravir, Dolutegravir, Bictegravir, Elvitegravir |
| Activation Requirement | No activation needed | No activation needed |
| Metabolism | Primarily by CYP3A4 (often requires ritonavir boosting) | Metabolized by UGT1A1 (Dolutegravir) or CYP3A4 (Elvitegravir) |
| Resistance Development | Requires multiple mutations → resistance develops more slowly | Resistance possible but less common in newer agents (e.g. Dolutegravir) |
| Drug Interactions | Extensive (CYP450 inhibitors/inducers) | Fewer interactions (caution with polyvalent cations, rifampin) |
| Common Side Effects | Hyperlipidemia, insulin resistance, GI upset, lipodystrophy | Insomnia, headache, weight gain, ↑ creatinine (non-toxic elevation) |
| Formulation Notes | Often co-formulated with ritonavir or cobicistat boosters | Available in fixed-dose combinations; well tolerated |
MCQs: Protease Inhibitors vs Integrase Inhibitors
1. Which enzyme is inhibited by Protease Inhibitors?
A. Reverse Transcriptase
B. Integrase
C. Protease
D. Fusion Protein
Answer: C. Protease
2. What is the main function of integrase in the HIV life cycle?
A. Cleaves polyproteins
B. Fuses the virus with host membrane
C. Incorporates viral DNA into host genome
D. Synthesizes viral RNA
Answer: C. Incorporates viral DNA into host genome
3. Which of the following is a commonly used Integrase Inhibitor?
A. Ritonavir
B. Efavirenz
C. Dolutegravir
D. Tenofovir
Answer: C. Dolutegravir
4. Which drug class is more likely to cause metabolic complications like dyslipidemia and insulin resistance?
A. Integrase Inhibitors
B. NRTIs
C. NNRTIs
D. Protease Inhibitors
Answer: D. Protease Inhibitors
5. Ritonavir is used in combination with other PIs primarily because:
A. It reduces their toxicity
B. It increases bioavailability by inhibiting CYP3A4
C. It prevents resistance development
D. It enhances renal excretion
Answer: B. It increases bioavailability by inhibiting CYP3A4