ARVS Flashcards
ARV classes and key names?
- Nucleoside.nucleotide reverse transcriptase inhibitors(NRTI)-“Dine”, “Bine”, “vir”(@ the end)
- Non-nucleoside reverse transcriptase inhibitors (NNRT)-“vir” in the middle
- Protease inhibitors(PIs)-“navir”
- Intergrase inhibitors-“Teger”
- Fusion inhibitor
- CCR5 Antagonist
Nucleoside nucleotide reverse transcriptase inhibitors(NRTI) drugs`/
D-E-A-L-S–T-Z
Didanosine
Emtricitabine (FTC)
Abacavir (ABC)
Lamivudine
(3TC)
Stavudine
- Tenofovir (TDF)
- Zidovudine (AZT, ZDV)
NRTI MOA?
Resemble nucleosides/nucleotides naturally used in DNA synthesis
Compete with host nucleotides to serve as the substrate for chain elongation by reverse
transcriptase
NRTI activation?
Must undergo intracellular activation to become active
Nucleoside analogs=Triphosphorylation
Nucleotide analog=Diphosphorylation
NRTI S/E?
Specify for Tenofovir(3), Zidovudine(1), Abacavir(1) and others(4)?
Tenofovir:
1. Nephrotoxicty
2. Fanconi syndrome
3. Bone demineralization disorders
Zidovudine:
1. Anemia
Abacavir:
1. Fatal hypersensitivity
(HLA-B*5701 gene)
All others:
1. Peripheral neuropathy
2. Lactic acidosis
3. Pancreatitis
4. LIpodystrophy,
NNRTIs drugs?
“vir”
- Efavirenz,
- Nevirapine
- Etravirine
- Rilpivirine
NNRTIs MOA?
1.Binding site of NNRTIs is different from that of NRTIs. Inhibit HIV reverse transcriptase
- Do not compete with nucleoside triphosphates.
- Do not require intracellular activation
NNRTIs A/E-3?
Specify three drugs!
EFV: abnormal dreams, psychosis, gynaecomastia, headache, mild to moderate
maculopapular rash
NVP: rash (may be severe or life-threatening - SJS), hepatitis
ETR: rash (may be severe or life-threatening - SJS), triglyceridaemia
Integrase Inhibitors drugs-3?
“teger”
- Dolutegravir
- Raltegravir
- Carbotegravir
Integrase Inhibitors drugs MOA?
- Inhibit viral integrase enzyme
- Prevent the transfer of viral DNA strand into host-cell genome
Raltegravir
- PK
- DI
- A/E
- Tolerance
PK: bioavailability enhanced by food
DI: Rifampicin ↓ raltegravir plasma levels
A/E: headaches, nausea, fatigue, myopathy, rhabdomyolysis
Tolerance:well-tolerated
Integrase Inhibitors MOA-2?
- Inhibit viral integrase enzyme
- Prevent the transfer of viral DNA strand into host-cell genome
Dolutegravir CI?
- DTG may increase the risk of neural tube defects avoid preconception
and in the first 6 weeks of pregnancy
Dolutegravir A/E?-6
- Tetratogenic
- insomnia
- weight gain
- headache
- neuropsychiatric effects
- diarrhea
Integrase Inhibitors DI?
- Antacids & iron supplements → ↓ Decreased DTG plasma conc. → Dose spacing
- Anticonvulsants (carbamazepine, phenobarbital, phenytoin) →↓ DTG
plasma conc. →→ Avoid co-admin if possible - Metformin → ↑↑↑Metforminplasma conc.→Limit metformin dose to max 500 mg 12-hourly
PIs drug-5?
“navir”
- Lopinavir
- Atazanavir
- Dorunavir
- Saquinavir
- Ritonavir
Ritonavir
Inhibits CYP3A4 at subtherapeutic doses
Inhibits metabolism of PIs
PIs MOA?
Inhibits HIV protease. Prevents cleavage of viral precursor & non-infectious virions
Lopinavir/ritonavir (LPV/r) A/E-4?
- Hyperglycaemia
- diarrhea
- dyslipidemia
- atherosclerosis
Atazanavir/ritonavir (ATV/r) A/E?
- Jaundice
- abdominal pain
Atazanavir/ritonavir (ATV/r) usauge?
Used if LPV/r is not well tolerated
Atazanavir/ritonavir (ATV/r) DI?
warfarin→↓ INR→↑ Coagulation
Darunavir/ritononavir (DRV/r) DI?
warfarin→↓ INR→↑ Coagulation
Darunavir/ritononavir (DRV/r) A/E?
- abdominal pain
- fatigue
- headache
Saquinavir/ritonavir (SQV/r) A/E?
Prolonged QT and PR intervals
Distinguish differences between DTG and EFV for HIV regimes
Check notes
First-line regimens formula?
2 NRTI + NNRTI or INSTI
Preferred first-line regimen?
2 NRTI + NNRTI or INSTI
Tenofovir + Lamivudine + Dolutegravir (TLD)
TDF + 3TC + DTG
Alternative first-line regimens for patients with TB?
Formula: 2 NRTI + NNRTI or INSTI
TDF + FTC + EFV (TEE)
Alternative first-line regimens for patients who are pregnant?
Formula: 2 NRTI + NNRTI or INSTI
TDF + FTC + EFV (TEE)
Alternative first-line regimens for patients who are Contraindications and intolerance to EFV?
Normal Formula: 2 NRTI + NNRTI or INSTI
TDF + FTC + DTG (TLD
Alternative first-line regimens for patients who are Contraindications with EFV & DTG?
Normal Formula: 2 NRTI + NNRTI or INSTI
TDF + 3TC/FTC + LPV/r
Second-line Regimens ususage?
When Failing on first-line regimen
Second-line Regimens formula?
Replace with DTG or PI
Zidovudine + (L/e) + Replacement (DTG or PI)
Second-line Regimens on Failing on NNRTI-based (TDF+3TC/FTC+EFV/NVP) 1st line regimen?
AZT + 3TC + DTG
Zidovudine + Lamivudine + Dolutegravir
Second-line Regimens if HBV positive?
Continue TDF because withdrawl may cause a fatal hepatitis flare
TDF + 3TC + DTG
Tenofovir+Lamivudine+ DTG
Second-line Regimens if HBV positive Contraindication/intolerance to DTG?
AZT + 3TC +LPV/r
Zidovudine + Lamivudine + Lopanavir
But,
if HBsAg positive:
TDF + 3TC +LPV/r
Second-line Regimens Contraindication/intolerance to TDF & AZT?
ABC + 3TC + LPV/r
Abacavir + Lamivudine + Lopinavir/Ritonavir
Second-line Regimens failing a InSTI-based (TDF+3TC+DTG) 1st line regimen (>2 years)
AZT + 3TC +LPV/r
But,
if HBsAg positive:
TDF + 3TC/FTC +LPV/r
Third-line Regimens?
Genotypic resistance test
resistance to LPV/r or ATV/r and/or DTG
3RD line regime drugs available?
- PI =Darunavir (DRV)
- Integrase inhibitor =Raltegravir (RAL)
- NNRTIs= Etravirine (ETR), Rilpivirine (RPV)(MVC)
- CCR5 blocker = Maraviroc (MVC)
Other drugs for 3rd regime drugs?
MOA
A/E
Efuvirtide(Fusion inhibitor)
MOA: Binds gp41 envelope glycoprotein thus preventing viral entry
A/E: Wheezing cough, numbness or tingling sensation
PrEP?
-2 NRTI
Tenofovir + Emtriceitabine
OR
Tenofovir + Lamivudine
Hepatitis combination with tenofovir
Post-exposure Prophylaxis (PEP)
TDF + 3TC + DTG
But,
If DTG contraindicated:
TDF + 3TC + ATV/r or LPV/r
If TDF contraindicated or source patient fails on TDF regimen:
AZT + 3TC + DTG
28-day Rx
Revise the below:
- Combinations to avoid
- Mitochondrial toxicity
3.
CHECK NOTES
Resistance in ART?
- K103N mutation
* reduces NVP and EFV susceptibility by about 50 and 20-fold,
respectively - K103S mutation
* usually occurs in samples from patients who previously had K103N
* causes intermediate to high-level resistance to EFV and NVP - K101P mutation
* Affects all NNRTIs
WHO, 2022
Co-trimoxazole Preventative Therapy(CPT)?
Prophylaxis of PJP adn toxoplamisis in HIV patients