2.1 Adult - Treatment of HIV-1 Infection
Oral Dosing
The recommended oral dose of zidovudine is 300 mg twice daily in combination with other antiretroviral agents.
2.2 Pediatric Patients (Aged 4 Weeks to Less than 18 Years)
Healthcare professionals should pay special attention to accurate calculation of the dose of zidovudine, transcription of the medication order, dispensing information, and dosing instructions to minimize risk for medication dosing errors.
Prescribers should calculate the appropriate dose of zidovudine for each child based on body weight (kg) and should not exceed the recommended adult dose.
Before prescribing zidovudine capsules or tablets, children should be assessed for the ability to swallow capsules or tablets. If a child is unable to reliably swallow a zidovudine capsule or tablet, the zidovudine oral solution should be prescribed.
The recommended dosage in pediatric patients aged 4 weeks to less than 18 years and weighing greater than or equal to 4 kg is provided in Table 1. Zidovudine oral solution should be used to provide accurate dosage when whole tablets or capsules are not appropriate.
Table 1: Recommended Pediatric Oral Dosage of Zidovudine
Body Weight (kg)
Total Daily Dose
Dosage Regimen and Dose
b.i.d.
t.i.d.
4 to <9
24 mg/kg/day
12 mg/kg
8 mg/kg
≥9 to <30
18 mg/kg/day
9 mg/kg
6 mg/kg
≥30
600 mg/day
300 mg
200 mg
Alternatively, dosing for zidovudine can be based on body surface area (BSA) for each child. The recommended oral dose of zidovudine is 480 mg per m2 per day in divided doses (240 mg per m2 twice daily or 160 mg per m2 three times daily). In some cases the dose calculated by mg/kg will not be the same as that calculated by BSA.
2.3 Prevention of Maternal-Fetal HIV-1 Transmission
The recommended dosage regimen for administration to pregnant women (greater than 14 weeks of pregnancy) and their neonates is:
Maternal Dosing
100 mg orally 5 times per day until the start of labor [see Clinical Studies (14.3)]. During labor and delivery, intravenous zidovudine should be administered at 2 mg per kg (total body weight) over 1 hour followed by a continuous intravenous infusion of 1 mg per kg per hour (total body weight) until clamping of the umbilical cord.
Neonatal Dosing
Start neonatal dosing within 12 hours after birth and continue through 6 weeks of age. Neonates unable to receive oral dosing may be administered zidovudine intravenously. See Table 2.
Table 2. Recommended Neonatal Dosages of Zidovudine
Route
Total Daily Dose
Dose and Dosage Regimen
Oral
8 mg/kg/day
2 mg/kg every 6 hours
Intravenous
6 mg/kg/day
1.5 mg/kg infused over 30 minutes, every 6 hours
2.4 Patients with Severe Anemia and/or Neutropenia
Significant anemia (hemoglobin less than 7.5 g per dL or reduction greater than 25% of baseline) and/or significant neutropenia (granulocyte count less than 750 cells per mm3 or reduction greater than 50% from baseline) may require a dose interruption until evidence of marrow recovery is observed [see Warnings and Precautions (5.1)]. In patients who develop significant anemia, dose interruption does not necessarily eliminate the need for transfusion. If marrow recovery occurs following dose interruption, resumption in dose may be appropriate using adjunctive measures such as epoetin alfa at recommended doses, depending on hematologic indices such as serum erythropoietin level and patient tolerance.
2.5 Patients with Renal Impairment
In patients maintained on hemodialysis or peritoneal dialysis or with creatinine clearance (CrCl) by Cockcroft-Gault less than 15 mL per min, the recommended dosage is 100 mg every 6 to 8 hours.
2.6 Patients with Hepatic Impairment
There are insufficient data to recommend dose adjustment of zidovudine in patients with impaired hepatic function or liver cirrhosis. Frequent monitoring of hematologic toxicities is advised [see Use in Specific Populations (8.7)].