Anti- retrovirals

Question 1

What are the risks of antiretroviral therapy?

Answer 1

1. Long-term drug toxicity, killing host cells along with the virus
2. Resistance due to disrupted usage
3. Cost of therapy and monitoring

Question 2

What is the classification/classes of anti-retroviral drugs

Answer 2

1. NRTIs
2. NNRTIs
3. PI
4. FI
5. CCR5 antagonist
6. Capsid inhibitor
7. Integrase strand inhibitors

Question 3

Give examples and explain the MOA of NRTIs

Answer 3

• Zidovudine, Stavudine, lamiviudine, Zidovine, acyclovir, valacyclovir, and famiciclovir.

Analogs of nucleotides thymidine, cytosine, adenine or guanine.

Once incorporated into the growing HIV viral DNA, it stops the process, preventing the conversion of RNA into double-stranded DNA

Question 4

Give examples and explain the MOA of NNRTIs

Answer 4

Nevriapine, Delviridine, rilpivirine

Inhibits the reverse transcriptase enzyme, preventing the conversion of single-stranded viral RNA into double stranded DNA

Question 5

Which class of anti-retroviral is considered to be the backbone of tx.

Answer 5

NRTIs
often used in combination with other classes

Question 6

explain the MOA of acyclovir triphosphate

Answer 6

• deoxy GTP functions as an analogue for guanine. Once incorporated into the growing DNA. strand, the reverse transcriptase process stops preventing the conversion of viral RNA into DNA

Question 7

Discuss examples and MOA of protease inhibitors

Answer 7

Doultegravir, Atazanavir, Darunivir

Protease inhibitors work by preventing the maturation virions, reducing viral replications

• Reversible inhibitors of the HIV aspartyl protease, responsible for the cleavage of viral polypeptide

Question 8

Discuss integrase inhibitors providing 2 examples and MOA

Answer 8

Raltegravir and elvitegravir

Prevents the integration of viral DNA into host DNA

Question 9

Discuss fusion inhibitors
- example
- MOA

Answer 9

Enfuviritide

prevents the HIV from entering the cell by blocking the fusion of the viral envelope with the host membrane. It interferes with the penetration of HIV by binding to the gp41 transmembrane glycoprotein blocking the structures needed for fusion

Question 10

Explain chemokine receptor antagonists
- Example
- MOA

Answer 10

Maravirorc

Blocks the CRR5 receptor, a co-receptor needed for HIV to enter

Question 11

Explain HAART

Answer 11

Combination of anti-retroviral therapy, reduce the progression to Aids leading to secondary infections and high mortality rates

NNRTI + 2NRTIs
e.g. nevirapine + Acyclovir and ziduvudine

PI + 2NRTIs
doultegravir + acyclovir and ziduvudine

3 NRTIS
Acyclovir, zidovudine + valaciclovir

Enhancer/booster = cobisistat or ritonavir

Question 12

Explain the properties of Lenacapvir

Answer 12

Pioneer HIV capsid inhibitor suited for multidrug-resistant HIV patients

Interferes with the HIV capsid a protein that protects a virus genetic materials and enzymes needed for replication

Administered under the skin every 6 months (initiation with tablet)

Prophylaxis to pre-exposure