FDA approve additional weight band dosing for children using atazanavir powder
FDA press notice
On 24 September 2015, the US FDA approved revisions to the atazanavir oral powder label to include dosing recommendations for patients three months and older weighing at least 5 kg.
This represents the addition of a new paediatric weight band. Previously the oral powder formulation was for patients three months and older weighing at least 10 kg.
Atazanavir oral powder must be taken with ritonavir and is not recommended for use in children who weigh less than 5 kg.
For children weighing 5 kg to less than 15 kg the daily dosage of atazanavir oral powder is 200 mg (4 packets) plus 80 mg ritonavir oral solution once daily. Only patients weighing 5 to less than 10 kg who do not tolerate the 200 mg (4 packets) dose of atazanavir oral powder and have not previously taken an HIV protease inhibitor, may take 150 mg (3 packets) atazanavir oral powder with close HIV viral load monitoring.
The safety profile of atazanavir in paediatric patients taking atazanavir oral powder was generally similar to that observed in clinical studies of atazanavir in paediatric patients taking atazanavir capsules. The most common Grade 3-4 laboratory abnormalities occurring in paediatric patients weighing 5 kg to less than 35 kg taking atazanavir oral powder were increased amylase (33%), neutropenia (9%), increased SGPT/ALT (9%), elevation of total bilirubin (>2.6 times ULN, 16%), and increased lipase (8%). All other Grade 3–4 laboratory abnormalities occurred with a frequency of less than 3%.
The pharmacokinetic parameters for atazanavir at steady state in paediatric patients taking the powder formulation are summarised in Table 1 below.
Atazanavir is marketed in the US by Bristol Myers-Squibb with the trade name Reyataz.
FDA HIV email list-serve (24 September 2015).
|Body weight (range in kg) (n)||atazanavir/ritonavir Dose (mg)||Cmax ng/mL Geometric Mean (CV%)||AUC ng*h/mL Geometric Mean (CV%)||Cmin ng/mL Geometric Mean (CV%)|
|5 to <10 (n=20)||150/80||4131 (55%)||32503 (61%)||336 (76%)|
|5 to <10 (n=10)||200/80||4466 (59%)||39519 (54%)||550 (60%)|
|10 to <15 (n=180)||200/80||5197 (53%)||50305 (67%)||572 (111%)|
|15 to <25 (n=32)||250/80||5394 (46%)||55687 (45%)||686 (68%)|
|25 to <35 (n=8)||300/100||4209 (52%)||44329 (63%)||468 (104%)|