Antiretroviral Drugs

Question 1

List 5 Nucleoside Reverse Transcriptase Inhibitors (NRTIs)

Answer 1

Tenofovir (TDF) 
Emtricitabine 
Lamivudine (3TC) 
Zidovudine (AZT) 
Stavudine (d4T)

Question 2

List 2 Non-Nuceloside Reverse Transcriptase Inhibitors (NNRTIs)

Answer 2

Efavirenz (EFZ)

Nevirapine (NVP)

Question 3

Name a Protease Inhibitors (PIs)

Answer 3

Lopinavir-ritonavir (LPV/r)

Question 4

Name a Integrase inhibitor

Answer 4

Dolutegravir (DTG)

Question 5

What is the classification of Zidovudine (AZT)?

Answer 5

Nucleoside Reverse Transcriptase Inhibitor

Question 6

What is the mechanism of action of Zidovudine (AZT)?

Answer 6

Inhibits nucleoside reverse transcriptase, stops the reverse transcription process and halts HIV replication

Question 7

What are the therapeutic indications of Zidovudine (AZT)? (3)

Answer 7

• selective toxic agent used against HIV
• decrease the perinatal transfer of HIV
• treatment of patients that are HIV-positive

Question 8

How is Zidovudine (AZT) administered?

Answer 8

orally or IV

Question 9

Describe the absorption of Zidovudine (AZT)

Answer 9

bioavailability is about 65% and peak plasma concentrations are reached in about 30 min (orally)

Question 10

What is the half-life of Zidovudine (AZT) and the active triphosphate?

Answer 10

AZT - 1 hour

active triphosphate - 3 hours

Question 11

Describe the distribution of Zidovudine (AZT)

Answer 11

adequate distribution in CSF

Question 12

What % of is Zidovudine (AZT) bound to plasma proteins?

Answer 12

30%

Question 13

Describe the metabolism of Zidovudine (AZT)?

Answer 13

metabolized in the liver to its inactive glucuronide

Question 14

Describe the excretion of Zidovudine (AZT)?

Answer 14

15% excreted unchanged in urine

Question 15

What are the adverse effects of Zidovudine (AZT)? (9)

Answer 15

• Anaemia
• Neutropenia
• GIT disturbances
• abnormalities of liver function
• nausea
• headache
• skin rash
• insomnia
• flu-like syndrome

Question 16

What is the classification of Nevirapine (NVP)?

Answer 16

Non-nucleoside reverse transcriptase inhibitor

Question 17

What is the mechanism of action of Nevirapine (NVP)?

Answer 17

bind to reverse transcriptase enzyme, blocks reverse transcription process

Question 18

What is the therapeutic indication of Nevirapine (NVP)?

Answer 18

prevent mother-to-baby transmission of HIV

Question 19

How is Nevirapine (NVP) administered?

Answer 19

orally

Question 20

Describe the absorption of Nevirapine (NVP)?

Answer 20

bioavailability is >90% and CSF level is 45% of that in the plasma

Question 21

Describe the metabolism of Nevirapine (NVP)

Answer 21

metabolized in the liver

Question 22

Describe the excretion of Nevirapine (NVP)

Answer 22

metabolite is excreted in the urine

Question 23

What are the adverse effects of Nevirapine (NVP)?

Answer 23

• rash
• Stevens-Johnson syndrome
• toxic epidermal necrolysis
• fulminant hepatitis
• headache
• fever
• lethargy

Question 24

What is the mechanism of action of integrase inhibitors?

Answer 24

Prevents HIV from integrating its genetic material into the host cell DNA by specifically blocking the action of the viral integrase enzyme

Question 25

What are the adverse effects of integrase inhibitors?

Answer 25

Can cause increased serum creatine kinase levels

Question 26

What is the mechanism of action of protease inhibitors?

Answer 26

Blocks the action of HIV protease enzyme, thus preventing cleavage of viral polyproteins into active proteins that are needed for the assembly of new viral particles

Question 27

What are the adverse effects of protease inhibitors? (8)

Answer 27

* Hyperglycemia * Gastrointestinal upset * Cushing-like syndrome * Renal toxicity (indinavir) * Thrombocytopenia (indinavir) * Inhibits cytochrome P450 (ritonavir) * paraesthesias around the mouth (ritonavir) * long term use: redistribution of fat (‘buffalo hump’)