Dosing & Uses
Dosage Forms & Strengths
tablet
- 10mg
Chronic Hepatitis B
10 mg PO qDay
Renal Impairment
CrCl ≥ 50 mL/min: Dose adjustment not necessary
CrCl 30-49 mL/min: 10 mg PO q48hr
CrCl 10-29 mL/min: 10 mg PO q72hr
Hemodialysis: 10 mg qWeek following dialysis
Dosage Forms & Strengths
tablet
- 10mg
Chronic Hepatitis B
<12 years old: Not recommended
≥12 years old: Administer as in adults, 10 mg PO qDay
Renal Impairment
CrCl ≥ 50 mL/min: Dose adjustment not necessary
CrCl 30-49 mL/min: 10 mg PO q48hr
CrCl 10-29 mL/min: 10 mg PO q72hr
Hemodialysis: 10 mg qWeek following dialysis
Interactions
Interaction Checker
No Results
Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor
Adverse Effects
>10%
Hematuria (11% vs 10% in placebo-treated)
Asthenia (13% vs. 14% placebo)
Hepatitis exacerbation (25%)
1-10%
Nausea (5%)
Flatulence (4%)
Diarrhea (3%)
Dyspepsia (3%)
Headache (9%)
Rash (1-10%)
Pruritus (1-10%)
Dyspepsia (5-9%)
Cough (6-8%)
Rhinitis (5%)
Increased AST/ALT
Abnormal liver function
Renal failure
Renal insufficiency
Increased serum Cr (2-3%)
Hypophosphatemia
Postmarketing Reports
Metabolism and nutrition disorders: Hypophosphatemia
Gastrointestinal disorders: Pancreatitis
Musculoskeletal system and connective tissue disorders: Myopathy, osteomalacia (manifested as bone pain and may contribute to fractures), both associated with proximal renal tubulopathy
Renal and urinary disorders: Renal failure, Fanconi syndrome, proximal renal tubulopathy
Warnings
Black Box Warnings
Severe acute exacerbations of hepatitis reported following discontinuing drug; monitor hepatic function
Chronic use may result in nephrotoxicity in patients with renal impairment or in those at risk of renal dysfunction; dose adjustment may be required
Resistance to HIV NRTIs may emerge in patients with chronic hepatitis B in whom HIV infection is unrecognized or untreated
Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, reported with nucleoside analogs alone or in combination with other antiretrovirals; obesity and prolonged nucleoside exposure may be risk factors
Contraindications
Hypersensitivity
Concurrent use with products containing tenofovir disoproxil fumarate or tenofovir alafenamide
Cautions
Discontinuation may result in severe acute exacerbation of hepatitis B
Patients who discontinue treatment: Monitor hepatic function for several months
Patients with renal dysfunction: Risk of nephrotoxicity (monitor and adjust dose accordingly)
Coadministration with drugs that reduce renal function may increase adefovir serum concentration
Do not administer with tenofovir (additive toxicity)
May increase HIV resistance in untreated patients who are HIV+
Risk of lactic acidosis, severe hepatomegaly with steatosis
To monitor fetal outcomes, Pregnancy Registry established: 1-800-258-4263
Pregnancy & Lactation
Pregnancy
There is pregnancy exposure registry that monitors pregnancy outcomes in women exposed during pregnancy; healthcare providers are encouraged to register patients by calling Antiretroviral Pregnancy Registry (APR) at 1-800-258- 4263
Prospective pregnancy data from APR are not sufficient to adequately assess risk of birth defects, miscarriage or adverse maternal or fetal outcomes; adefovir disoproxil (ADV) use during pregnancy has been evaluated in a limited number of individuals reported to APR and the number of exposures to adefovir is insufficient to make a risk assessment compared to a reference population; estimated background rate for major birth defects is 2.7% in the U.S. reference population of Metropolitan Atlanta Congenital Defects Program (MACDP); estimated rate of miscarriage is not reported in APR; all pregnancies have a background risk of birth defect, loss, or other adverse outcomes
Animal data
- In animal reproduction studies with oral ADV, no adverse developmental effects were observed at exposures (Cmax) 23 times higher in rats and 40 times higher in rabbits than those at recommended human dose (RHD)
Lactation
It is not known whether adefovir is present in human breast milk, affects human milk production, or has effects on breastfed infant
The developmental and health benefits of breastfeeding should be considered along with mother’s clinical need for therapy and any potential adverse effects on breastfed infant from drug or from underlying maternal condition
Pregnancy Categories
A:Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B:May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C:Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D:Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X:Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA:Information not available.
Pharmacology
Mechanism of Action
Acyclic nucleotide analog; inhibits HBV DNA polymerase; inhibition blocks reverse transcriptase activity, which in turn reduces viral DNA synthesis
Absorption
Bioavailability: 59%
Peak plasma time: 0.58-4 hr
Peak plasma concentration: 18.4±6.26 ng/mL
AUC: 220±70 ng•hr/mL
Distribution
Protein Bound: ≤ 4%
Vd: 317-467 mL/kg
Metabolism
Rapidily converted to adefovir from the diester prodrug, adefovir dipivoxil
Metabolites: Adefovir (active)
Elimination
Half-life: 7.48±1.65 hr
Renal clearance: 231±48.9 mL/min
Excretion: Urine; renal glomerular filtration, active tubular secretion
Dialyzable: Yes
Images
Patient Handout
Formulary
Adding plans allows you to compare formulary status to other drugs in the same class.
To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.
Adding plans allows you to:
- View the formulary and any restrictions for each plan.
- Manage and view all your plans together – even plans in different states.
- Compare formulary status to other drugs in the same class.
- Access your plan list on any device – mobile or desktop.
