HEP B and C therapeutics Flashcards
risk factors for Hep B transmission
- IV drug use
- contact with blood
- multiple sexual partners
- mother to infant
Hep B anti-HBc+ indicates
prior exposure
HBsAg+ indicates
current hep B infection
Hep B anti-HBs+ indicates
immunity from vaccine or previous infection
hep B HBeAg+ indicates
active Hep B replication
hep B HBV DNA+ indicates
active Hep B replication
immediate prophylaxis for Hep B
hepatitis B immune globulin IM injection
Hep B vaccine scedule
at 0, 1 month, 6 months
which hep B tests to do first when checking for status
anti-HBc and HBsAg
if initial hep B tests come out positive what tests to follow up with
HBeAg
HBV DNA
ALTs
when to vaccinate adults for hep B
when all tests come up negative
how to test for efficacy to hep B vaccine
have antiHBs+ (immunity)
antiHBc-
HBsAg-
(not from past exposure or infection)
phases of chronic HBV
- immune tolerant
- HBeAg-positive immune active
- inactive chronic hep B
- HBeAg-negative immune reactivation
HBV immune tolerant phase lab values
- ALT normal
- HBV DNA >1 million
- HBeAg positive
- minimal liver fibrosis
Inactive chronic hep B phase lab values
- ALT normal
- HBV DNA <2,000 (low or undetectable)
- HBeAg negative
- variable fibrosis
HBeAg positive immune active phase labs
- ALT elevated
- HBV DNA >20,000
- HBeAg positive
- moderate to severe inflammation/fibrosis
HBeAg-negative immune reactivation phase labs
- ALT elevated
- HBV DNA >2,000
- HBeAG negative
- mod-severe inflammation/fibrosis
why is HBV not curable
gets incorporated into the nucleus of the cell
lab goals of treatment in HBV
- HBV DNA -
- convert HBeAg- to anti-HBe+
- convert HBsAg- to anti-HBs+ (rarely done)
- normalize ALT and AST
secondary goal of HBV treatment
reduce progression to cirrhosis, liver cancer
indications for treatment of HBV
-HBeAg-positive/negative immune active phase
elevated ALT, HBV DNA, liver damage
treatment options in HBV
interferon lamivudine adefovir entecavir telbivudine tenofovir
Interferon alfa regimen
sc weekly for 48 weeks
interferon alfa adverse effects
flu like symptoms depression alopecia thrombocytopenia leukopenia
patients best suited for interferon alfa treatment
- low baseline HBV DNA
- short disease duration
- HBeAg+
patients least suited for interferon alfa treatment
HIV coinfection
regimen for nucleotide/side analogs
all oral once daily
telbivudine adverse effect
myopathy w/ CK elevation
adefovir adverse effect
nephrotoxicity, especially in decomp cirrhosis
not used much
TDF adverse effects
nephrotoxicity
reduced bone mineral density
TAF adverse effects
low risk nephrotoxicity
clearance of HBsAg by drug groups
interferon - good
nucleotide/sides - bad
in HBV if nucleotide/side resistance what are pts at risk of
acute hepatitis
increased ALT and DNA
HBV drugs with low drug resistance
entecavir
tenofovir
treatment criteria for chronic HBV
- if ALT is >2x or significant histology
- normal ALT with some fibrosis/inflammation and over 40 years old
treatment drugs for chronic HBV
entecavir
tenofovir
peg-inf
treatment drugs for chronic HBV with cirrhosis
compensated:
entecavir
tenofovir
decompensated:
combo therapy
term for hep C cure
sustained virologic response
sustained virologic response
no detectable HCV in the blood at 12 or more weeks after therapy is complete
3 drug classes used in HCV regimens
NS3/5
NS5B
NS5A
+/- ribavirin
duration of HCV regimens
8-24 weeks
typically 12
HCV drugs to avoid in liver disease
aka use these in renal insufficiency
PrOD/PrO +/- RBV
Grazoprevier/elbasvir +/- RBV
Glecaprevir + pibrentasvir
challenges of HCV treatment
- hepatic failure/decompensation
- many DDIs (amiodarone big one)
- reactivation of hep B
HCV drugs recommended for decompensated cirrhosis
sofosbuvir velpatasvir ledipasvir daclatasvir \+/- RBV
protease inhibitor regimens are not recommended when in HCV
decompensated cirrhosis
most common drug interactions with HCV drugs
st. john's wort rifampin phenobarbital carbamazepine phenytoin amiodarone
other drug classes to consider avoiding or adjusting when using HCV drugs
statins
PPIs
H2RAs
antacids
main cyp and transporters to be worried about in DDIs for HCV drugs
pgp
BCRP
3A4
antivirals that have pH dependent absorption
ledipasvir
velpatasvir
ledipasvir and PPI use
take simultaneously
velpatasvir and PPI use
not recommended
if necessary take 4 hours prior to omeprazole
H2RA instructions with DAA
take together or 12 hours apart
antacids instructions with DAA
separate by 4 hours
if reactivation of hep B occurs in HCV treatment when does it usually occur
4-8 weeks
for genotype 1a a positive RAS test treatment
GRZ+EBR
add RBV
16 week duration
for genotype 1a a negative RAS test treatment
GRZ+EBR
no RBV
12 week duration
for genotype 3 a positive RAS test treatment
VEL+SOF or DCV+SOF
add RBV
for genotype 3 a negative RAS test treatment
VEL+SOF or DCV+SOF only
RBV adverse effects
nausea insomnia cough rash anemia (get tested q2wk until stable) teratogen
DAAs tolerability
mild side effects when used without RBV
headache
fatigue
nausea
labs to consider for DAAs
CBC q2wk with RBV
creatinine
hepatic function
HCV genotype
tests to assess efficacy of HCV drugs
HCV PCR at week 4 and week 12 after treatment
