Left part is for HIV, right part is for other virus.
| Class | Example(s) | Mechanism of action |
|---|---|---|
| NRTI | Tenofovir, emtricitabine, lamivudine, abacavir, zidovudine | Inhibits HIV DNA synthesis from RNA template by terminating DNA chain elongation NRTI: Competitive nucleoside/nucleotide RT inhibitor |
| NNRTI (-vir-) | Efavirenz, nevirapine | NNRTI: Allosteric RT inhibitor |
| PI (-navir) | Atazanavir, darunavir, indinavir, ritonavir | Inhibits HIV polyprotein cleavage |
| Integrase inhibitor (-gravir) | Dolutegravir, raltegravir | Inhibits HIV DNA integration into host genome |
| Fusion inhibitor | Enfuvirtide | Inhibits HIV fusion with target cell membrane by binding to HIV gp41 |
| CCR5 antagonist | Maraviroc | Inhibits HIV entry by blocking the HIV gp120 allosteric interaction with CCR5 (tropism testing required) |
NRTIs (Nucleoside reverse transcriptase inhibitors)
- Medications in class
- Abacavir (ABC)
- Didanosine (ddI)
- Emtricitabine (FTC)
- Lamivudine (3TC)
- Stavudine (d4T)
- Tenofovir (nucleotide analog, also called nucleotide reverse-transcriptase inhibitor; NtRTI)
- Tenofovir disoproxil (TDF)
- Tenofovir alafenamide (TAF)
- Zidovudine (ZDV, formerly AZT)
- Mechanism of action
- NRTIs act as nucleoside analogs → competitive blockage of nucleoside binding to reverse transcriptase → inhibition of formation of 3’ to 5’ phosphodiester linkages → termination of DNA chain → inhibition of RNA to DNA reverse transcription
- Activation requires intracellular phosphorylation, into their active triphosphate form like natural nucleotides
- thus, NRTI efficacy is reliant on kinase availability and activity, which varies depending on cell functionality and activation state.
- Adverse effects
- Abacavir hypersensitivity reaction
- Potentially life-threatening systemic reaction consisting of fever, rash, constitutional symptoms, vomiting, diarrhea, and, occasionally, respiratory distress
- Avoid abacavir in HLA-B*5701-positive patients.
- Pancreatitis: didanosine, stavudine
- Abacavir hypersensitivity reaction
Mnemonic
Zidovudine → get rid of hemoglobin → anemia
NNRTIs
- Mechanism of action
- Noncompetitive inhibitors of viral reverse transcriptase that bind to the reverse transcriptase at a different location than NRTIs
- NNRTIs do not require intracellular phosphorylation for activation because they are direct inhibitors.
(The dog is trying to poop in the den)
Protease inhibitors
NAVIR → never
Integrase inhibitors
Mnemonic
Integrase → -tegravir
Fusion inhibitors
Mnemonic
- Enfuvirtide inhibits fusion.
- Mazda → Maraviroc
ART regimens
- 2 NRTIs PLUS 1 NNRTI
- 2 NRTIs PLUS 1 PI (boosted)
- 2 NRTIs PLUS 1 INI