On December 18, 2008
FDA approved new pediatric dosing recommendations for a new 75
mg Prezista (darunavir) tablet formulation for patients from 6
to less than 18 years of age.
Section 1 Indications and Usage,
Section 2 Dosage and Administration, and Section 3 Dosage Forms
and Strenghts were modified to reflect the changes.
Dosing recommendations are
provided based on the pharmacokinetic, activity and safety data
from study TMC114-C212 in children 6- <18 years of age. A
description of study TMC114-C212 including the pharmacokinetic,
safety and activity results, and rationale for dose selection
for children were included in Section 6 Adverse Reactions,
Section 8 Use in Specific Populations, Section 12 Clinical
Pharmacology and Section 14 Clinical Studies as shown below.
1 Indications and Usage
1.2 Pediatric Patients.
PREZISTA, co-administered with ritonavir (PREZISTA/rtv), and
with other antiretroviral agents, is indicated for the treatment
of HIV infection in pediatric patients 6 years of age and older
[see Use in Specific Populations (8.4)].
This indication is based on
24-week analyses of plasma HIV RNA levels and CD4+ cell counts
from an open-label Phase 2 trial in antiretroviral
treatment-experienced pediatric patients 6 to < 18 years of age.
2 Dosage and
Administration
2.2 Pediatric
Patients (age 6 to < 18 years)
Do not use once daily dosing in pediatric patients.
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/rtv for each individual child based
on body weight (kg) and should not exceed the recommended dose
for treatment-experienced adults.
Before prescribing PREZISTA,
children should be assessed for the ability to swallow tablets.
If a child is unable to reliably swallow a tablet, the use of
PREZISTA tablets may not be appropriate.
The recommended dose of PREZISTA/rtv
for pediatric patients (6 to < 18 years of age and weighing at
least 44 lbs (20 kg)) is based on body weight (see Table 1) and
should not exceed the recommended treatment-experienced adult
dose (PREZISTA/rtv 600/100 mg b.i.d.). PREZISTA tablets should
be taken with ritonavir twice daily and with food.
Table 1:
Recommended Dose for Pediatric Patients (6 to < 18 years of age)
for Prezista Tablets with ritonavir
Body
Weight |
Dose |
(kg) |
(lbs) |
|
> 20 kg – < 30 kg
|
> 44 lbs – < 66 lbs
|
375 mg
PREZISTA/50 mg ritonavir twice daily
|
> 30 kg – < 40 kg
|
> 66 lbs – < 88 lbs
|
450 mg PREZISTA/60 mg ritonavir
twice daily
|
> 40 kg
|
>
88 lbs |
600 mg PREZISTA/100 mg ritonavir
twice daily
|
The safety and efficacy of
PREZISTA/rtv in pediatric patients 3 to < 6 years of age have
not been established.
PREZISTA/rtv should not be used
in pediatric patients below 3 years of age [see Warnings and
Precautions (5.11) and Nonclinical Toxicology (13.2)].
3 Dosage Forms and
Strengths
3.1 PREZISTA 75 mg
Tablets
PREZISTA (darunavir) 75 mg tablets are supplied as white,
caplet-shaped, film-coated tablets containing darunavir
ethanolate equivalent to 75 mg of darunavir per tablet. Each
tablet is debossed with “75” on one side and “TMC” on the other
side.
6 Adverse Reactions
6.6 Clinical Trials
Experience: Treatment-Experienced Pediatric Patients
PREZISTA/rtv has been studied in 80 antiretroviral
treatment-experienced HIV-1-infected pediatric subjects 6 to
< 18 years of age and weighing at least 44 lbs (20 kg) in
combination with other antiretroviral agents [see Use in
Specific Populations (8.4) and Clinical Studies (14.4)].
Frequency, type, and severity of
ADRs in pediatric subjects were comparable to those observed in
adults. ADRs to PREZISTA/rtv (all grades, ≥ 3%), excluding
laboratory abnormalities reported as ADRs, were vomiting (13%),
diarrhea (11%), abdominal pain (10%), headache (9%), rash (5%),
nausea (4%) and fatigue (3%).
Grade 3 or 4 laboratory
abnormalities were ALT increased (Grade 3: 3%; Grade 4: 1%), AST
increased (Grade 3: 1%, Grade 4: 0%), pancreatic amylase
increased (Grade 3: 4%, Grade 4: 1%), pancreatic lipase
increased (Grade 3: 1%, Grade 4: 0%), total cholesterol
increased (Grade 3: 1%), and LDL increased (Grade 3: 3%).
8
Use in Specific Populations
8.4 Pediatric Use
PREZISTA/rtv should not be used in pediatric patients below
3 years of age because of toxicity and mortality observed in
juvenile rats dosed with darunavir (from 20 mg/kg to 1000 mg/kg)
up to days 23 to 26 of age [see Warnings and Precautions (5.11),
Use in Specific Populations (8.1), Clinical Pharmacology (12.3)
and Nonclinical Toxicology (13.2)].
The pharmacokinetics, safety,
tolerability, and efficacy of PREZISTA/rtv in pediatric patients
3 to < 6 years of age have not been established.
PREZISTA/rtv once daily should
not be used in pediatric patients.
The safety, pharmacokinetic
profile, and virologic and immunologic responses of PREZISTA/rtv
were evaluated in treatment-experienced HIV-1-infected pediatric
subjects 6 to < 18 years of age and weighing at least 44 lbs
(20 kg) [see Adverse Reactions (6.6), Clinical Pharmacology
(12.3) and Clinical Studies (14.4)]. Frequency, type, and
severity of adverse drug reactions in pediatric subjects were
comparable to those observed in adults [see Adverse Reactions
(6.6)]. Please see Dosage and Administration (2.2) for dosing
recommendations for pediatric subjects 6 to < 18 years of age
and weighing at least 44 lbs (20 kg).
12.3 Pharmacokinetics
Pediatric Patients
The pharmacokinetics of darunavir in combination with ritonavir
in 74 antiretroviral treatment-experienced HIV-1-infected
pediatric subjects 6 to < 18 years of age and weighing at least
44 lbs (20 kg) showed that the administered weight-based dosages
resulted in darunavir exposure comparable to that in
treatment-experienced adults receiving PREZISTA/rtv 600/100 mg
twice daily [see Dosage and Administration (2.2)].
Table 9:
Population Pharmacokinetic Estimates of Darunavir Exposure
(Study TMC114-C212) Following Administration of Doses in Table 1
Parameter
Median (Range) |
PREZISTA/rtv twice
daily
N = 74 |
AUC24h (ng∙h/mL)
|
127340 (67054-230720)
|
C0h (ng/mL)
|
3888 (1836-7821)
|
N = number of subjects with data.
*AUC24h is calculated as AUC12h*2
|
14 CLINICAL STUDIES
Pediatric Patients:
The pharmacokinetic profile, safety and antiviral activity of
PREZISTA/rtv was evaluated in a randomized, open-label,
multicenter study. This study enrolled treatment-experienced
pediatric subjects between the ages of 6 and < 18 years and
weighing at least 44 lbs (20 kg). Patients were stratified
according to their weight (≥ 20 - < 30 kg, ≥ 30 - < 40 kg,
≥ 40 kg) and received PREZISTA/rtv plus background therapy
consisting of at least two non-protease inhibitor antiretroviral
drugs. Eighty patients were randomized and received at least one
dose of PREZISTA/rtv. Pediatric subjects who were at risk of
discontinuing therapy due to intolerance of ritonavir oral
solution (e.g., taste aversion) were allowed to switch to the
capsule formulation. Of the 44 pediatric subjects taking
ritonavir oral solution, 23 subjects switched to the 100 mg
capsule formulation and exceeded the weight-based ritonavir dose
without changes in observed safety.
The 80 randomized pediatric
subjects had a median age of 14 (range 6 - < 18 years), and were
71% male, 54% Caucasian, 30% Black, 9% Hispanic and 8% other.
The mean baseline plasma HIV-1 RNA was 4.64 log10 copies/mL, and
the median baseline CD4+ cell count was 330 cells/mm3 (range:
6 to 1505 cells/mm3). Overall, 38% of pediatric subjects had
baseline plasma HIV-1 RNA ³ 100,000 copies/mL. Most pediatric
subjects (79%) had previous use of at least one NNRTI and 96% of
pediatric subjects had previously used at least one PI.
Seventy-seven pediatric subjects
(96%) completed the 24 week period. Of the patients who
discontinued, one patient discontinued treatment due to an
adverse event. An additional 2 patients discontinued for other
reasons, one patient due to compliance and another patient due
to relocation.
The proportion of pediatric
subjects with HIV-1 RNA < 400 copies/mL and < 50 copies/mL was
64% and 50%, respectively. The mean CD4+ cell count increase
from baseline was 117 cells/mm3.
The dose selection was based on
the following:
- Similar darunavir plasma
exposures in children compared to adults
- Similar virologic response rates
and safety profile in children compared to adults
The complete revised labeling
will be posted soon on the FDA web site at
Drugs@FDA.
Prezista is a Protease Inhibitor,
manufactured by Tibotec Inc.
Richard Klein
Office of Special Health Issues
Food and Drug Administration
Kimberly Struble
Division of Antiviral Drug Products
Food and Drug Administration
|