Darunavir dosage and administration

# Dosage and Administration

### Adult Patients
PREZISTA must be co-administered with ritonavir to exert its therapeutic effect. Failure to correctly co-administer PREZISTA with ritonavir will result in plasma levels of darunavir that will be insufficient to achieve the desired antiviral effect and will alter some drug interactions.
Patients who have difficulty swallowing PREZISTA tablets can use the 100 mg/mL PREZISTA oral suspension.
The recommended oral dose of PREZISTA is 800 mg (one 800 mg tablet or two 400 mg tablets or 8 mL of the oral suspension) taken with ritonavir 100 mg (one 100 mg tablet/capsule or 1.25 mL of a 80 mg/mL ritonavir oral solution) once daily and with food. An 8 mL darunavir dose should be taken as two 4 mL administrations with the included oral dosing syringe.
For antiretroviral treatment-experienced patients genotypic testing is recommended. However, when genotypic testing is not feasible, PREZISTA/ritonavir 600/100 mg twice daily dosing is recommended.

### Pediatric Patients (age 3 to less than 18 years)
Healthcare professionals should pay special attention to accurate dose selection of PREZISTA, transcription of the medication order, dispensing information and dosing instruction to minimize risk for medication errors, overdose, and underdose.
Prescribers should select the appropriate dose of PREZISTA/ritonavir for each individual child based on body weight (kg) and should not exceed the recommended dose for adults.
Before prescribing PREZISTA, children weighing greater than or equal to 15 kg should be assessed for the ability to swallow tablets. If a child is unable to reliably swallow a tablet, the use of PREZISTA oral suspension should be considered.
The recommended dose of PREZISTA/ritonavir for pediatric patients (3 to less than 18 years of age and weighing at least 10 kg is based on body weight (see Tables 2, 3, 4, and 5) and should not exceed the recommended adult dose. PREZISTA should be taken with ritonavir and with food.
The recommendations for the PREZISTA/ritonavir dosage regimens were based on the following:
Results from two trials in treatment-experienced pediatric subjects 3 to less 18 years of age demonstrating similar darunavir plasma exposures, virologic response rate and safety profile compared to treatment-experienced adults.
Results from one trial in treatment-naive pediatric subjects 12 to less than 18 years of age demonstrating similar darunavir plasma exposures, virologic response rate and safety profile compared to treatment-naive adults.
Results from population pharmacokinetic modeling and simulation in children 3 to less than 12 years of age predicting similar darunavir plasma exposures compared to treatment-naive adults. Although no clinical trial was conducted to collect exposure-safety data, the predicted exposures from the once daily dosing is supported by exposures observed in a pediatric clinical trial where twice-daily dosing was administered.
Dosing recommendations for treatment-naive pediatric patients or antiretroviral treatment-experienced pediatric patients with no darunavir resistance associated substitutions

### Pediatric patients weighing at least 10 kg but less than 15 kg
The weight-based dose in antiretroviral treatment-naive pediatric patients or antiretroviral treatment-experienced pediatric patients with no darunavir resistance associated substitutions is PREZISTA 35 mg/kg once daily with ritonavir 7 mg/kg once daily using the following table.

### Pediatric patients weighing at least 15 kg
Pediatric patients weighing at least 15 kg can be dosed with PREZISTA oral tablet(s) or suspension using the following table:

## Dosing recommendations for treatment-experienced pediatric patients with at least one darunavir resistance associated substitutions

### Pediatric patients weighing at least 10 kg but less than 15 kg
The weight-based dose in antiretroviral treatment-experienced pediatric patients with at least one darunavir resistance associated substitution is PREZISTA 20 mg/kg twice daily with ritonavir 3 mg/kg twice daily using the following table:

### Pediatric patients weighing at least 15 kg
Pediatric patients weighing at least 15 kg can be dosed with PREZISTA oral tablet(s) or suspension using the following table:
Do not use PREZISTA/ritonavir in pediatric patients below 3 years of age .

### Patients with Hepatic Impairment
No dose adjustment is required in patients with mild or moderate hepatic impairment. No data are available regarding the use of PREZISTA/ritonavir when co-administered to subjects with severe hepatic impairment; therefore, PREZISTA/ritonavir is not recommended for use in patients with severe hepatic impairment .