exam 3 Flashcards
echinocandins
candida
aspergillus
polyenes
candida
aspergillus
histoplasma
blastomyces
coccidioides
broadest!
Broadest spectrum of all antiFUNGAL drugs; rough side effects
polyenes
azoles
candida (most)
aspergillus (most)
some:
cryptococcus
histoplasma
blastomyces
flucytosine
candida
cryptococcus
antifungal target:
cell wall synthesis
echinocandins
“itching to cross the wall”
antifungal target:
cell membrane pores alteration
polyenes
“Pores=Polyenes”
antifungal target:
Ergosterol (Cell Membrane) Synthesis
azoles
“azOLes = ergosterOL”
antifungal target:
Nucleic Acid Synthesis
5-flucytosine
“cytosine”
MOA
INHIBIT (1, 3) β-D-glucan synthase, which synthesizes B (1, 3) glucan fibrils, which are essential to the _____ _____
echinocandins
cell wall
__________fungin
echinocandins
what is the biggest disadvantage of echinocandins
IV administration only
MOA
Amphipathic compounds, bind to ergosterol in the cell membrane create pores, pores change the membrane permeability and allow increased leakage of intracellular components death of fungi occurs
polyenes
amphotericin B
nystatin
polyenes
Drug of choice for the treatment of life-threatening invasive/systemic fungal infections
NOT affected by renal or hepatic function!
amphotericin B
3 main adverse effects of amph B
infusion reaction
(cytokine =IgG); premedicate!
nephrotoxicity (permanent!)
anemia (reversible!)
antifungal
- Monitor kidney function, electrolytes, CBC
decreases K and mag
amph B
what 3 drugs are used to premedicate with amph B
tylonel
benadryl
hydrocortisone
lipid formulations
amph B
benefits and drawbacks
Slowly releases AmphB; reduced risk of nephrotoxicity
Reduced incidence of infusion reactions
20-50x more expensive*
2 examples of lipid form of amph B
abelcet (complex)
ambisome (vehicle/pod)
cmax is higher!
polyenes
antagonistic with _________*
azoles
“A=A”
Azoles eliminate ergosterol, but this is the target of polyenes (amph B)
polyenes
synergistic with _________ + _____________*
echinocandins
flucytosine
Inhibit fungal 14 a-demethylase (CYP450-CYP51) reduction in ergosterol levels cell membrane permeability issues
Levels of squalene and lanosterol go up increased toxicity
azoles
All systemic AZOLE antifungals are ____azoles; except for ketoconazole, which is an imidazole*
TRIazoles (3 nitrogens)
except for ketoconazole (2 nitrogens)
Fungistatic=low dose
fungicidal=high dose
azoles
which azole is oral only
itraconazole
which azole IS the only one that is RENALLY eliminated*
which 2 azoles have the vehicle (renal toxic)
fluconazole
posaconazole, voriconazole
which azole does NOT cause QT prolongation***
isavuconazole, “isabella”
which azole has significant safety concerns regarding ORAL tablets
Ketoconazole “Killer”
severe liver injuries
adrenal insufficiency
QT prolong
lots of drug-drug interactions
which drug means you should NOT give AZOLES
warfarin
which 2 azoles require acidity “take with a coke”
ITRAconazole
VORIconazole
“itra + vori are acidic hoes”
which azole is contraindicated in CHF
ITRAconazole
can cause photosensitivity and visual disturbances*
azole
VORIconazole
what part of the azole causes nephrotoxicity*
the VEHICLE it is in
cresemba is a prodrug that does NOT have this vehicle
- MOA
Fluorinated analog of the nucleobase cytosine
related to 5 FU (an anticancer drug); can impact both DNA and RNA synthesis; fungal cells have cytosine permease (an enzyme) that brings flucytosine (5-FC) into the cell gets converted to 5-FU (by cytosine deaminase) gets converted into nucleotides get incorporated into RNA and DNA
flucytosine
inhibits RNA/protein + DNA synthesis
which 2 enzymes are involved with flucytosine
permease: brings it into the cell
deaminase: converts to 5-FU
true or false
2 enzymes permease and deaminase make flucytosine SELECTIVE since they do not exist in humans
true
which antifungal is NEVER used alone
flucytosine
which antifungal class is the ONLY one that causes QT prolongation
azoles (triazoles)
true or false
all viruses depend on host to replicate
true
what is the ONLY antiVIRAL that is CIDAL*
hep C drugs
what type of ssRNA is similar to our RNA
positive ssRNA
where are most antiviral targets
nucleic acid replication
what does mimicking mean for antivirals*
Mimicking means you bypass the 1st step of phosphorylation (which is often rate limiting) you already start with a monophosphate
true or false
once a person is infected with HERPES, they are infected for life
true
patients with renal dysfunction (2)
decrease dose
extend dosing interval
MOA
o NucleoSIDE analog, inhibits viral DNA synthesis - blocks viral DNA polymerase
Activated by a viral kinase (the virus has their own kinase*)
o Only the infected cells will activate/phosphorylate the drug into triphosphate
acyclovir + ganciclovir
herpes
which antiVIRAL is good for solid organ transplant
HIV patients*
ganciclovir
o Inhibits spermatogenesis → USE CONTRACEPTION
o Bone marrow suppression
o Carcinogenic
o Teratogenic
ganciclovir
what are the 2 drugs that are good for CMV, HSV (herpes) RESISTANT antivirals
cidofovir (mimics monophosphate = bypasses 1st step of phosphorylation*)
foscarnet (keeps triphosphate from binding, NO phosphorylation)
what is the most common form of herpes resistance
mutations in viral kinases
what are the 2 newest herpes antivirals
letermovir (bone marrow transplant)
maribavir
Current treatments are NOT curative
Disease IS preventable with a vaccine
hep B
all HBV (hep B) antiviral agents inhibit HBV ________________
polymerase
Lactic acidosis, severe hepatomegaly
Can cause HIV resistance in patients with unrecognized or untreated HIV
hep B (HBV) antivirals
which HBV antiviral is
active against HIV, but is NOT approved to use with HIV*
adefovir
what 3 drugs can be used for HBV or HIV
tenofovir disoproxil
tenofovir alafenamide
epivir
what drug is the BEST for HIV or HBV
tenofovir ALAFENAMIDE
(less in the plasma, less nephrotoxicity/bone toxicity)
no vaccine
treatment can eliminate it
hep C
what is the most common genotype of hep C
1B
what is the direct acting antiviral targets (DAA) for
hep C HCV
antiviral
________buvir*
NS5B polymerase (blue) inhibitors
HCV hep C
“B= Buvir”
antiviral
__________asvir*
NS5A cofactor (orange) inhibitors
HCV hep C
“A= Asvir”
antiviral
__________previr*
NS3/4A protease (green) inhibitors
HCV hep C
“Previr=Protease”
true or false
NON-nucleoside (nucleotide) does NOT need to be phosphorylated
true
true or false
hep C drugs are often combined (hitting at 2 targets)
true
which drugs are
contraindicated with strong INDUCERS of Pgp/CYP3A4
means it will DECREASE levels
DAA (hep C)
antacids, H2, PPIs (absorption reduced)
amiodarone (bradycardia)
CYP3A4 inducers
DAA drugs (hep C)
what are the 4 main HIV drugs involved in blocking* 1) attachment
2) interaction
or
3) fusion
“entry inhibitors”
fostemsavir
maraviroc
ibalizumab
fuzeon
MOA
inhibit the reverse transcriptase inhibitor, preventing formation of DNA from HIV RNA
reverse transcriptase inhibitors
nucleoside/tide require _______________ (competitively inhibit RT)
NON-nucleoside/tide do NOT require _________________
(non-competitive binding to RT)
phosphorylation
Class Boxed Warning:
lactice acidosis with hepatomegaly with steatosis
NRTIs (nucleoside/tide RT inhibitors)
for HIV
hypersensitivity reactions, test for HLA-B1507
Abacavir (does NOT require renal dosing)
which HIV drug is good for labor/childbirth
Zidovudine
which 2 HIV classes have CYP450 interactions
NNRTIs (NON nucleoside/tide RT inhibitors)
protease inhibitors
MOA
Prevent the covalent insertion/integration of HIV + prevent formation of HIV provirus
integraase inhibitors
“____________tegravir”
Due to extensive first pass metabolism (and Pgp transport), administer with a PK Booster!
what are the 2 boosters* they INHIBIT CYP3A4, protect from metabolism
Protease inhibitors (PIs)
ritonavir
cobicstat
MOA
Competitively inhibit the cleavage of non-functional viral precursor proteins into functional proteins
protease inhibitors
antiviral
adverse effects include
insulin resistance
hyperlipidemia
protease inhibitors
what combos of drugs are used for pre-exposure prophylaxis for HIV
- Tenofovir alafenamide + emtricitabine (Descovy)
- Tenofovir disoproxil + emtricitabine (Truvada)
what are most common flu types
A, B
MOA
Blockage of the neuraminidase enzyme that normally cleaves the virus that is tethered to the host cell now the virus is PERMANENTLY tethered to the infected host cell
tamiflu, relenza,
rapivab (IV ONLY)
(flu)
inhibits endonuclease activity of RNA polymerase, prevents cap-snatching (normally, the flu virus “steals” the cap from our mRNA to replicate)
xofluza
which antifungal causes bone marrow suppression*
flucytosine
which antifungal binds to ergosterol
amph B (polyenes)
which antifungal reduces cell membrane integrity by blocking synthesis of ergosterol
azoles
which antifungals cause histamine reactions
echinocandins
which adjunctive measure is used to LESSEN nephrotoxicity for amph B
normal saline infusion (not benadryl!)
A patient in the ICU on IV fentanyl (CYP3A4) started on IV VORICONAZOLE***(inhibitor CYP3A4) should be monitored for:
resp depression and sedation
Which of the following are true regarding the azole antifungals? 3
hepatotoxic
teratogenic
affect metabolism of other drugs
Which PK booster has protease inhibitory activity
rotonivir
someone is infected with a HSV-2 strain that LACKS thymidine kinase activity and should be treated with
cidofovir
foscarnet
(herpes resistant drugs)
Which one of the following is an anti-HSV agent that is dependent on viral thymidine kinase phosphorylation
acyclovir
which herpes antiviral does NOT require phosphorylation in order to inhibit viral DNA sysnthesis
foscarnet