HIV

Question 1

Examples of NRTIs

Answer 1

Abacavir
Didanosine
Emtricitabine
Lamivudine
Stavudine
Tenofovir
Zidovudine

Question 2

Mechanism of action of NRTIs

Answer 2

Act as nucleoside analogs –> competitively blocks nucleoside binding to reverse transriptase –> inhibits formation of 3’ to 5’ phosphodiester linkages –> termination of DNA chain –> inhibition of RNA to DNA reverse transcription

Question 3

General adverse effects of NRTIs

Answer 3

Mitochondrial toxicity
Lactic acidosis
HIV associated lipodystrophy

Question 4

Abacavir specific adverse effects

Answer 4

Increase cardiovascular events
Hypersensitivity reactions
Avoid in HLA B5701 positive patients

Question 5

What HIV medication causes pancreatitis

Answer 5

Didanosine
Stavudine

Question 6

What HIV medication is associated with cardiovascular disease/increased risk of MI

Answer 6

Abacavir

Question 7

What HIV medication is associated with nephrotoxicity

Answer 7

Tenofovir
TDF > TAF

Question 8

What HIV medication is associated with OP

Answer 8

Tenofovir
TDF > TAF

Question 9

What HIV medication is associated with bone marrow suppression

Answer 9

Zidovudine

Question 10

What HIV medications cause peripheral neuropathy

Answer 10

Stavudine
Didanosine
Zalcitabine

Question 11

Examples of protease inhibitors

Answer 11

ends with “navir”
Atazanavir
Darunavir
Lopinavir
Indanavir

Question 12

MOA of protease inhibitors

Answer 12

Inhibits viral HIV-1 protase –> production of immature virions (non-infectious)

Question 13

Adverse effects of protease inhibitors

Answer 13

GI upset
Nephrolithiasis, crystal-induced nephropathy, haematuria
Metabolic abnormalities - hyperglycaemia, dyslipidemia, lipodystrophy
Increased risk of bleeding in patients with haemophilia
Changes to hair e.g. thinning

Question 14

Advantage of ritonavir

Answer 14

Ritonavir is CYP450 inhibitor
Can be used in subtherapeutic doses to increase concentrations of other HIV drugs

Question 15

Which HIV medication with teratogenic?

Answer 15

Efavirenz

Question 16

Which HIV medication causes indirect hyperbilirubinaemia

Answer 16

Atazanavir

Question 17

Specific adverse effect of nevirapine

Answer 17

Severe hepatotoxicity in higher doses

Question 18

CD4 200-500

Answer 18

Tuberculosis

Question 19

CD4 < 200

Answer 19

PJP
Cryptosporidium
Candida
Fungal pneumonia

Question 20

CD4 < 100

Answer 20

Toxoplasmosis
Candida, HSV, CMV oesophagitis

Question 21

CD4 < 50

Answer 21

CMV
Cryptococcus
MAC
Primary CNS lymphoma

Question 22

Pathophysiology of HIV

Answer 22

1) HIV enters body and attaches to CD4 receptor with gp120 glycoprotein binding
2) Viral envelope fuses with host cell and capsid enters the cell
- for fusion, CD4 receptor and coreceptor (CCR5 in macrophages and CCR5 or CXCR4 in T cells) must be present
- CCR5 mainly occurs during early stages, CXCR4 occurs in later stages
3) Virion’s RNA transcribed into dsDNA vy viral reverse transcriptase and then integrated into host’s DNA by viral intergrase
4) Viral DNA is replicated and virions are assembled

Question 23

MOA of NNRTIs

Answer 23

Nonnucleoside reverse transcriptase inhibitors
Binds to reverse transcriptase at different location

Question 24

Examples of NNRTIs

Answer 24

Efavirenz
Nevirapine

Question 25

General adverse effects of NNRTIs

Answer 25

Hypersensitivity reactions
SJS

Question 26

MOA of integrase inhibitors

Answer 26

Inhibition of viral integrase –> blockade of viral DNA integration into host’s DNA –> inhibition of viral replication

Question 27

Examples of inegrase inhibitors

Answer 27

Ends with “-gravir”
Bictegravir
Dolutegravir
Raltegravir

Question 28

Examples of entry inhibitors and MOA

Answer 28

Enfuvirtide - fusion inhibitor, competitively binds to gp41
Maraviroc - CCR5 antagonist, inhibition of gp120 interaction