Study Notes and MCQ on Anti-HIV Drugs for BPharm, Nursing, Medical and Paramedical Courses
Notes on Anti-HIV Drugs
1. HIV Lifecycle Overview
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Entry → Reverse Transcription → Integration → Transcription & Translation → Assembly → Budding → Maturation
2. Classes of Anti-HIV Drugs
| Drug Class | Mechanism of Action |
|---|---|
| NRTIs (Nucleoside RT Inhibitors) | Inhibit reverse transcriptase by acting as false substrates |
| NNRTIs (Non-nucleoside RT Inhibitors) | Bind to reverse transcriptase directly and inhibit enzyme activity |
| PIs (Protease Inhibitors) | Inhibit HIV protease enzyme, preventing viral protein maturation |
| INSTIs (Integrase Inhibitors) | Inhibit viral integrase, blocking integration of viral DNA into host genome |
| Fusion Inhibitors | Block fusion of HIV with host cell membrane |
| CCR5 Antagonists | Block CCR5 co-receptor on T-cells, preventing HIV entry |
| Post-Attachment Inhibitors | Block CD4 binding after virus attaches, preventing further entry steps |
Comparative Chart of Anti-HIV Drug Classes
| Class | Examples | Site of Action | Resistance Risk | Key Adverse Effects | Clinical Notes |
|---|---|---|---|---|---|
| NRTIs | Zidovudine, Tenofovir | Reverse transcriptase | Moderate | Lactic acidosis, lipodystrophy | Backbone of ART |
| NNRTIs | Efavirenz, Nevirapine | Reverse transcriptase | High | CNS symptoms, rash | Long half-life |
| PIs | Ritonavir, Lopinavir | Protease enzyme | Low | Hyperlipidemia, GI upset | Often boosted with ritonavir |
| INSTIs | Raltegravir, Dolutegravir | Integrase | Low | Insomnia, headache | Preferred in modern regimens |
| Fusion Inhibitor | Enfuvirtide | Viral envelope | Low | Injection site reactions | Subcutaneous administration |
| CCR5 Antagonist | Maraviroc | Host CCR5 receptor | Variable | Hepatotoxicity, URI | Tropism testing required |
| Post-Attachment Inhibitor | Ibalizumab-uiyk | CD4 after virus binds | Unknown | Diarrhea, rash | Used in multidrug-resistant HIV |
MCQs on Anti-HIV Drugs
1. Which of the following is a Nucleoside Reverse Transcriptase Inhibitor (NRTI)?
A. Efavirenz
B. Tenofovir
C. Ritonavir
D. Maraviroc
Answer: B. Tenofovir
2. What is the mechanism of action of Protease Inhibitors?
A. Prevent fusion of virus with the host cell
B. Inhibit integration of viral DNA
C. Inhibit maturation of viral proteins
D. Block CCR5 receptors on host cells Answer: C. Inhibit maturation of viral proteins
3. Which drug class targets the CCR5 co-receptor?
A. INSTIs
B. NNRTIs
C. CCR5 Antagonists
D. Fusion Inhibitors Answer: C. CCR5 Antagonists
4. A patient on Efavirenz is most likely to experience which side effect?
A. Nephrotoxicity
B. CNS disturbances
C. Peripheral neuropathy
D. Hypoglycemia Answer: B. CNS disturbances
5. Which anti-HIV drug requires subcutaneous administration?
A. Dolutegravir
B. Raltegravir
C. Enfuvirtide
D. Ibalizumab Answer: C. Enfuvirtide