Lactic acidosis and severe hepatomegaly with steatosis, including fatalities, reported with nucleoside analogs, including tenofovir disoproxil fumarate in combination with other antiretrovirals; most were reported in women; obesity and prolonged nucleoside exposure may be risks factors
Discontinuation of antihepatitis B drugs may result in severe acute exacerbations of hepatitis B
Owing to the risk of development of HIV-1 resistance, tenofovir AF alone is not recommended for the treatment of HIV-1 infection; test for HIV-1 before initiating treatment
Lactation
Unknown if distributed in human breast milk
Consider the developmental and health benefits of breastfeeding along with the mother?s clinical need for the drug, and any potential adverse effects on the breastfed infant from the drug or from the underlying maternal condition
Indication
Chronic Hepatitis B Infection
Contra Indication
Hypersensitivity
Dose
N/A
Side Effect
1-10%
Headache (9%)
ALT >5 x ULN (8%)
Abdominal pain (7%)
Fatigue (6%)
Cough (6%)
Glycosuria >3+ (5%)
Nausea (5%)
Back pain (5%)
Pregnancy Category
Name :
Not Classified
Description
FDA has not yet classified the drug into a specified pregnancy category.
Mode of Action
Tenofovir alafenamide (AF) is a nucleotide reverse transcriptase inhibitor (NRTI) and a phosphonamidate prodrug of tenofovir
Compared with tenofovir disoproxil fumarate (tenofovir DF, Viread), tenofovir AF is a more targeted form of tenofovir that has demonstrated high antiviral efficacy at a dose that is 10 times lower than tenofovir DF, as well as an improved renal and bone safety profile
Tenofovir AF as a lipophilic cell-permeant compound enters primary hepatocytes by passive diffusion and by the hepatic uptake transporters OATP1B1 and OATP1B3 and is converted to tenofovir diphosphate
Tenofovir diphosphate inhibits HBV replication through incorporation into viral DNA by the HBV reverse transcriptase, which results in DNA chain-termination
Interaction
Drugs that induce P-gp result in decreased tenofovir AF absorption and plasma concentrations, which may lead to loss of therapeutic effect (eg, carbamazepine, oxcarbazepine, phenobarbital, phenytoin, rifabutin, rifampin, rifapentine, St John?s wort)
Drugs that inhibit P-gp and BCRP may increase tenofovir AF absorption and plasma concentration.
Coadministration of tenofovir AF with drugs that reduce renal function or compete for active tubular secretion may increase concentrations of tenofovir and other renally eliminated drugs, and this may increase the risk of adverse reactions
Some examples include acyclovir, cidofovir, ganciclovir, valacyclovir, valganciclovir, aminoglycosides, high-dose or long-term NSAD use
Pregnancy Category Note
Pregnancy
There are no human data on use in pregnant women to inform a drug-associated risks of adverse fetal developmental outcome
In animal studies, no adverse developmental effects were observed when tenofovir alafenamide was administered during the period of organogenesis at exposure equal to or 51 times (rats and rabbits, respectively) the tenofovir alafenamide exposure at the recommended daily dose
Lactation
Unknown if distributed in human breast milk
Consider the developmental and health benefits of breastfeeding along with the mother?s clinical need for the drug, and any potential adverse effects on the breastfed infant from the drug or from the underlying maternal condition
Adult Dose
Chronic Hepatitis B Infection
Indicated for treatment of chronic hepatitis B virus (HBV) infection in adults with compensated liver disease
25 mg PO qDay with food
Hepatic impairment
Mild (Child-Pugh A): No dosage adjustment required
Decompensated (Child-Pugh B or C) hepatic impairment: Use not recommended
Child Dose
N/A
Renal Dose
Renal impairment
Mild, moderate, or severe: No dosage adjustment required
ESRD (CrCl <15 mL/min): Use not recommended
Administration
Take with food
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The information provided herein are for informational purposes only and not intended to be a substitute for professional medical advice, diagnosis, or treatment. Please note that this information should not be treated as a replacement for physical medical consultation or advice. Great effort has been placed to provide accurate and comprehensive data. However, Medicart along with its authors and editors make no representations or warranties and specifically disclaim all liability for any medical information provided on the site. The absence of any information and/or warning to any drug shall not be considered and assumed as an implied assurance of the Company.