HIV medicine Flashcards
list all the entry inhibitors
Maraviroc
list the fusion inhibitors
Enfuvirtide
list the NTRIs- which are nucleoside vs nucleotide inhibitors
nucleoside: abacavir, didanosine, lamivudine, emtricitiabine, stavudine, zidovudine
nucleotide: tenofovir
list the NNTRIs- which are first gen?
Delavirdine (1st gen) Efavirenz (1st gen) Nevirapine (1st gen) Etravirine Rilpivirine
”–vir–
list the INSTIs
Dolutegravir
Elvitegravir
Raltegravir
“gravir”
list the protease inhibitors
Atazanavir Darunavir Fosamprenavir Indinavir Lopinavir Nelfinavir Ritonavir Saquinavir Tipranavir
“-navir”
outline the life cycle of HIV
1- HIV iron binds to host CD4 cells via: HIV membrane proteins gp41 and gp120 bind CD4 membrane CD4-RTK and chemokine GPCRs
(CCR5- another membrane chemokine receptor on the CD4 cell that will bind the CD4-gp120 complex to stabilize it= allow fusion of virus membrane with target cell)
2- uncoating of viral RNA
3-single stranded HIV RNA is REVERSE TRANSCRIBED into DNA
4-INTEGRATION: ‘viral DNA’ is inserted into host genome
VIRON ASSEMBLY: gene transcription machinery is hijacked by virus to produce viral proteins and immature noninfectious visions
5-BUDDING AND MATURATION: after proteolytic cleavage via HIV aspartyl protease, the HIV visions can fully mature and become infectious
maraviroc
- MOA
- use
- pharmacokinetics
- resistance
- AEs
- special notes
- Bind to CCR5 to prevent entry= specific and selective binding
- Combo use w/ other antiretrovirals only if CCR5-tropic HIV
- Oral , CYP3A4 substrate
- Muts in V3 loop of gp120 : Emergence of CXCR4-tropic virus”
- Generally ok : Systemic allergic reaction, then hepatotoxicity
- co-receptor tropism should be tested before starting
enfuvirtide
1. MOA
- pharmacokinetics
- resistance
- AEs
- Bind gp41 to prevent conformational/structural changes needed for fusion of the viral envelope with host cell
- Synthetic 36 amino-acid peptide : subQ : Metab via proteolytic hydrolysis w/o CYP450
- Muts in gp41
- Local injection reaction : Insomnia, headache, dizziness, nausea : Rarely hypersensitivity”
NTRIs
- MOA
- Use
- Resistance
- Competitive inhib of HIV reverse transcriptase at active site
Incorporated into growing viral DNA chain»premature chain termination due to inability to bind next nucleotide - Include in tx regimen for nearly all pt beginning antiretroviral therapy
. Combo w/ other drugs from different classes to make HIV tx regimens - Point mutations in HIV reverse transcriptase
. Impaired kinase activity to prevent phosphorylation and activation of the drug (different for nucleosides and nucleotides)
. No cross resistance between NNRTI and NRTI
abacavir
- pharmacokinetics
- AEs
- Guanosine analog
. Available in fixed dosage combo
. metabolized by alcohol dehydrogenase—> if take with alcohol, can increase serum levels= - Hypersensitivity: 8% of pt in first 6wk: SOB/sore throat/cough, skin rash in 50%
-STOP if have hypersensitivity
. pancreatitis (rare)
Didanosine
- pharmacokinetics
- AEs
- special notes
- synthetic analog of deoxyadenosine (an altered Adenosine)
- Dose dependent pancreatitis
- Retinal changes w/ optic neuritis (children, high doses in adults)
- Inc risk of lactic acidosis and hepatic steatosis when combined with stavudine - mandated periodic retinal exams to watch out for the optic neuritis
Lamivudine
- pharmacokinetics
- AEs
- special notes
- Cytosine analog
- Uncommon, if so v general (fatigue, dry mouth, HA/dizzy, GI)
- Lamivudine and emtricitabine select for the same point mutation in HIV reverse transcriptase
- USED IN HIV AND HBV
Emtricitabine
- pharmacokinetics
- AEs
- special notes
- Fluorinated analog of lamivudine
- Long intracellular T1/2=once daily dose - rash, Hyperpigmentation of palms/soles, particularly in African Americans
- Lamivudine and emtricitabine select for the same point mutation in HIV reverse transcriptase
- USED IN HIV AND HBV
- -Tenofovir + emtricitibine =brand name Travuda
Stavudine
- pharmacokinetics
- AEs
- Thymidine analog
- Dyslipidemia = most common with Stavudine than other NTRIs
- dose dependent peripheral sensory neuropathy
- Inc risk lactic acidosis and hepatic steatosis if combined with didanosine
Zidovudine
- pharmacokinetics
- AEs
- Deoxythymidine analog
- Macrocytic anemia and Neutropenia (both rare)
- GI intolerance, HA, insomnia - will resolve with therapy
Tenofovir
- pharmacokinetics
- AEs
- special notes
- Acyclic nucleotide analog of adenosine
- Disoproxil or alafenamide prodrugs enhance oral absorb - farts
- ALSO USED AGAINST HIV AND HBV
- Tenofovir + emtricitibine =brand name Travuda
what drugs can be used to treat both HIV and HBV
Tenofivir (A-analog)
Lamivutidine and Emtricitabine (C-analogs)
Ta-cLE both HIV and HBV)
NNRTIs
- MOA
- Resistance
- general AEs shared by all drugs
- metabolism
- Bind to HIV reverse transcriptase not at binding site, Binding–> conformational change in enzyme –> decreased activity =non competitive inhibitor
- rapidly develop w/ mono therapy
- HIV reverse transcriptase point mutation that alter NNRT binding - all will have GI intolerance, rash
- all are substrates of CYP3A4
is there cross-resistance between NRTIs and NNRTIs
no
Delavirdine (1st gen)
- use
- pharmacokinetics
- AEs
- Not used very often bc comparatively weak
- Extensive metab by CYP3A4 and CYP2D6
- Skin rash in 38%
- ha, fatigue, nausea, diarrhea, aminotransferase increased
Efavirenz (1st gen)
- pharmacokinetics
- AEs
- Metab by CYP3A4 and CYP2B6 : Once daily bc long T1/2
- CNS (50%): dizzy, drowsy, insomnia, nightmares, ha
- Skin rash (28%)
Nevirapine (1st gen)
- use
- pharmacokinetics
- AEs
- Prevent HIV transmission from mom to baby
- Metab by CYP3A4
- Rash (20%): can be dose limiting , Liver toxic (4%)
Etravirine
- use
- pharmacokinetics
- AEs
- Designed to overcome HIV resistance to first gen NNRTIs
- Substrate and inducer of CYP3A4
,
- inhibitor or CYP2C9 and CYP2C19
- a diarylpyrimidine - Rash, nausea, diarrhea
Rilpivirine
- pharmacokinetics
- AEs
- special notes
- a diarylpyrimidine
- Metab by CYP3A4 - High doses assoc with QT prolongation
- rash, depression, HA, Insomnia, increased serum aminotransferases - Coformulated w/ emtricitabine and tenofovir = a fixed dose combination
INSTIs
- MOA
- AE
- bind HIV integrase
- Inhibit strand transfer and prevents ligation of reverse-transcribed HIV DNA into the chromosome of the host cell - headache, GI effects are most common
Dolutegravir
- use
- pharmacokinetics
- Preferred agent for tx of tx-naive pt when combo
2. T1/2 14h
Elvitegravir
- pharmacokinetics
- special notes
- Requires boosting to work—give w/ cobicistat
3. Only in combo pill (elvitegravir + cobicistat + emtricitabine + tenofovir)
Raltegravir
- use
- pharmacokinetics
- Preferred tx for tx-naive pt : mono
2. T1/2 9h
Protease Inhibitors
- MOA
- resistance
- AEs associated with the class
- metabolism
- Block HIV protease and prevent maturation of final structural proteins that make the virion core
- Specifically and competitively inhibits HIV aspartyl protease - Develop quick w/ mono therapy
- GI intolerance,
Lipodystrophy- metabolic (hyperglycemia, hyperlipidemia) or morphologic (lipoatrophy, fat deposition)
Redistribution and accumulation of body fat
- All are metabolized by CYP3A4= lots of potential drug-drug interactions
- most with Ritonavir and least with Saquinivir
Atazanavir
- use
- pharmacokinetics
- AEs
- special notes
- Frequently prescribed
- once daily dose
- Inhibits CYP3A4, CYP2C9, UGT1A1 - Diarrhea and nausea Skin rash
- Not associated with dyslipidemia or hyperglycemia
Darunavir
- pharmacokinetics
- AEs
- special notes
- Metab by CYP3A system
- rash (2-7%)
- Potential hypersensitivity if sulfa allergy - Must be co-admin w/ ritonavir or cobicistat
Fosamprenavir
- use
- pharmacokinetics
- AEs
- Often give with low dose ritonavir
- Prodrug: amprenavir=active
- ha, nausea, dirrhea, personal paresthesias, depression
- Potential hypersensitivity if sulfa allergy
Indinavir
- pharmacokinetics
- AEs
- special notes
- Boost with ritonavir to allow for 2x daily dosing ( but also incr chance for kidney stone)
- Unconjugated bilirubinemia and nephrolithiasis
- Drinking 48 ounces of water helps to prevent kidney stones
Lopinavir
- AEs
- special notes
- Generally well tolerated
4. Only available in combo w/ low dose ritonavir
Nelfinavir
- AEs
- Diarrhea and farts
Ritonavir
- use
- pharmacokinetics
- AEs
- special notes
- Primarily used as a booster
- Lower dose used for inhibit CYP3A4 - Most pronounced inhibitory effect on CYP3A4
- High rate of GI side effects at standard doses
- limited at low dose
Saquinavir
- use
- pharmacokinetics
- AEs
- Reformulated for once daily dose with ritonavir
- Least pronounced inhibit effects on CYP3A4
- nausea, diarrhea, abdominal discomfort, dyspepsia
- Less when boosted by ritonavir
Tipranavir
- use
- AEs
- special notes
“1. Indicated in pt resistant to other protease inhibitors ”
“3. diarrhea, nausea, vomiting, abdominal pain 2. Urticarial or maculopapular rash 3. Potential hypersensitivity in pt w/ sulfa allergy “
- Combine w/ ritonavir
what is the formula for an HAART
Highly active antiretroviral therapy (HAART)
“2 NRTIs plus either:
1 protease inhibitor (sometimes 2 for boosting)
1 NNRTI
1 INSTI”
what are the two HAARTs that are the preferred trx for trx-naive patients
- Abacavir + lamivudine + dolutegravir
2. Tenofovir + emtricitibine + dolutegravir
elvitegravir is only available in this combo
Tenofovir + emtricitabine + elvitegravir+cobicistat
darunivir MUST be given with either ___ or ___
and can be seen in what HAART combo
darunivir MUST be given with either ritonavir or cobicistat
- Tenofovir + emtricitibine + (darunavir+ritonavir)
brand name Travuda = __+__
Tenofovir + emtricitibine
Efivirenz is only available in this once a day combo pill
brand name= Atripla
Tenofovir +emtricitabine + efavirenz
rilpivirine is only available when coformulated in this combo:
Tenofivir + emtriciitabine + Rilpirivine
abacavir is only available as what two fix dosed combos
(abacavir + zidovudine)
(abacavir + lamivudine)