Children

The recommended dose of abacavir (Ziagen) for infants and children between three months and twelve years of age is 8mg/kg twice a day, up to a maximum dose of 600mg a day.¹ There are limited data to suggest that a dose of 2mg/kg twice daily may be suitable for infants 30 days or younger.

Children weighing between 14kg and 20kg may receive one 300mg tablet once daily or half of one 300mg tablet twice daily. Children weighing 20kg-25kg may receive one and a half 300mg tablets once daily, or a full tablet and a half tablet split between morning and evening doses.

Abacavir does not need to be dosed with food. Patients who are HLA-B*5701 positive should not use abacavir; testing should be considered prior to therapy initiation (see Hypersensitivity reaction).

The 48-week PENTA 5 study demonstrated that lamivudine with abacavir offered better virological suppression and growth than did regimens with a NNRTI backbone of either zidovudine/lamivudine or zidovudine and abacavir. It should be preferred as a first-line NRTI backbone.²

After five years of follow-up, 31% of children who started treatment with abacavir and lamivudine had changed regimens versus 39% of the children initially randomised to zidovudine/lamivudine, and 46% of children taking zidovudine and abacavir. Patients taking abacavir/lamivudine were significantly less likely to change therapy with an undetectable viral load than were patients in either of the other two treatment arms, indicating the tolerability of the abacavir/lamivudine regimen.