Pharmacology-ART Guidelines

Question 1

What type of lymphadenopathy is significant?

Answer 1

Axillary and lymphadenopathy > 1cm.

Question 2

What is used to measure viral load? What is used to measure immune function?

Answer 2

Plasma HIV RNA PCR. CD4 count is key in determining when to start prophylaxis for opportunistic infections and ART.

Question 3

Goal of ART

Answer 3

Maximize viral suppression in blood. Note that suppression will not be comprehensive and replication will still be going on in the lymph nodes.

Question 4

Clinical criteria for initiation of ART regardless of CD4 count

Answer 4

AIDS defining illness, pregnant, nephropathy, HBV, acute opportunistic infection and > 50 yrs old.

Question 5

Recommendations for initating ART based on CD4 count

Answer 5

< 200. < 350 + Hx of AIDS-defining illness. 350-500. > 500 data is inconsistent. Also consider if there is a rapid decline in CD4 cells (800 -> 400).

Question 6

Why would you withhold ART in a patient that qualifies for them?

Answer 6

Non-compliance and other medical conditions that may be exacerbated by the side effects.

Question 7

5 classes of drugs used for HIV

Answer 7

1) Entry inhibitors (Maraviroc) 2) Fusion inhibitors (Fuzeon) 3) RT inhibitors (AZT) 4) Integrase inhibitors (Raltegravir) 5) Protease inhibitors (Indinavir)

Question 8

NRTIs I should know

Answer 8

Zidovuidine (AZT) is not really used. Lamivudine (3TC), Emtricitabine (FTC), Abacavir (ABC) and Tenofovir (TNF) all have additional activity against Hep B.

Question 9

NNRTIs I should know

Answer 9

Efavirenz (backbone drug).

Question 10

PIs I should know

Answer 10

Keletra (lopinivir + ritonavir), Atazanavir, Darunavir. These are backbone agents.

Question 11

Backbone agents. What do you combine them with?

Answer 11

Protease inhibitors, NNRTI or integrase inhibitor. These will drop the viral load by 2-2.5 logs. You combine the backbone agents with 2 NRTIs which are weaker inhibitors that only trop viral load by .5-1.5 logs.

Question 12

Safest NRTI

Answer 12

Lamivudine

Question 13

What do you have to do before prescribing Abacavir?

Answer 13

Get a genotype looking for HLA-B*5071 because these people have hypersensitivity and anaphylaxis. NEVER RECHALLENGE BECAUSE OF LIFE-THREATENING ANAPHYLAXIS.

Question 14

Drug associated with Fanconi’s syndrome?

Answer 14

NRTI: Tenofovir. This is in combination with emtricitibine in Truvada.

Question 15

Backbone of atripla, the most common ART therapy?

Answer 15

NNRTI: Efavirenz. It is combines with emtricitabine and tenofovir NRTIs.

Question 16

Side effect of efavirenz?

Answer 16

Nightmares, they go away over time.

Question 17

Toxicities associated with protease inhibitors?

Answer 17

P450 interactions, insulin resistance, hyperglycemia, diabetes, dyslipidemia, fat redistribution and MI.

Question 18

What is ritonavir typically used for?

Answer 18

To boost other protease inhibitors. It blocks clearance of other PIs.

Question 19

Common side effect of indinavir?

Answer 19

The actual drug crystalizes to form kidney stones (not calcium oxalate, etc)

Question 20

Common side effect of atazanavir

Answer 20

Hyperbilirubinemia

Question 21

Classes of drugs you use for salvage if patients become resistant to normal drugs?

Answer 21

T20 (fusion inhibitor). Note that this is not used often because patients have to inject themselves two times a day. Maraviroc (CCR5 antagonist entry inhibitor). Note that this will only work if HIV is specific for CCR5. Raltegravir and dolutegravir (integrase inhibitors and backbone agents).

Question 22

Dual mixed tropism in HIV

Answer 22

Tropism for CCR5 and CXCR4

Question 23

How do you enhance patient compliance?

Answer 23

Prescribe the least number of pills, avoid “d” drugs

Question 24

Quad pill (stribilid) used to avoid CNS effects that follow atripla use?

Answer 24

Has Elvitegravir (integrase inhibitor), cobicistat (CP3A inhibitor prolongs drug life), tenofovir and emtricitabine.

Question 25

When do you consider C-section for a pregnant woman with HIV?

Answer 25

Viral load > 1000

Question 26

When do you start ART in a pregnant woman who has normal CD4 count and low viral load?

Answer 26

12-14 weeks

Question 27

When do start a baby on ART who had an HIV+ mother

Answer 27

6-12 hours after birth

Question 28

How do you monitor ART?

Answer 28

Check for compliance at 4-6 weeks, get CD4 (recovery may take months to years) and viral load to see how meds are working, check glucose/lipids/LFTs/CBC for toxicity. After this initial follow-up, then see at 3 month intervals.

Question 29

Most common cause of virologic failure?

Answer 29

Non-adherence. This allows for development of resistant viruses and increases in viral load.