In 2008, the US FDA approved the use of Kaletra (LPV/RTV)) in children 14 days of age and older. In the European Union, the drug is indicated for children two years and older, dosed by weight, in combination with other ARVs. EU marketing approval for the low-dose tablet was given in 2008.

The liquid formulation is highly concentrated, contains 80mg LPV/20mg RTV per ml, should be taken with food, and never exceed a dose of 5ml twice daily. The low-dose paediatric tablet contains 100mg LPV/25mg RTV (half the standard adult dose) and can be taken with or without food as part of a HAART regimen. Neither formulation requires refrigeration. Once-daily dosing is not advised in children.

Paediatric dosing is based on body weight (kg) or body surface area (BSA per m2) up to 40 kilos. Dosing for infants aged 14 days to six months using the liquid formulation is twice daily at 300mg LPV per m2 BSA/75mg RTV per m2 BSA. By weight, dosing is 16mg LPV per kg/4mg RTV per kg. In this age group, co-administration of efavirenz, nevirapine, fosamprenavir, or nelfinavir is not recommended.1 

The US paediatric guidelines warn that use of 300mg LPV per m2 in those under six months of age, and particularly in those under six weeks of age, is associated with lower trough levels than are found in adults. Consequently, infants need to be evaluated frequently for dose adjustments. After an infant died from an overdose on the liquid solution in 2007, Abbott sent out an advisory reminding physicians that Kaletra in children must be calculated by body weight until the child is 40 kilos and should never exceed 5ml, given twice daily.

After six months, dosing by BSA per m2 is 230mg LPV/57.5mg RTV twice daily. If dosing by weight, children <15 kilos would receive 12mg/LPV per kg/3mg RTV per /kg twice daily. In children 15 to 40 kilos, dosing is 10mg LPV per kg/2.5mg RTV per kg twice daily.

Using the low-dose tablets (100mg LPV/25mg RTV), children would receive twice-daily dosing per kilo or by BSA (m2) as follows:

  • 2 tablets for those 15 to 25 kilos or BSA ≥0.6 to <0.9 
  • 3 tablets for those >25 to 35 kilos or BSA ≥0.9 to 1.4
  • 4 tablets for those >35 kilos or BSA ≥1.4 or 2 full-strength (200mg LPV/50mg RTV) tablets.  

This dosing would need to be adjusted in children aged 6 months to 18 years if they were also receiving efavirenz, nevirapine, fosamprenavir, or nelfinavir. Again using the low-dose tablets, children would receive twice-daily dosing per kilo or by BSA (m2) as follows:

  • 2 tablet for those 15 to 20 kilos or BSA ≥0.6 to <0.8 
  • 3 tablets for those >20 to 30 kilos or BSA ≥0.8 to 1.2
  • 4 tablets for those >30 to 45 kilos or BSA ≥1.2 to <1.7 (or 2 full-strength tablets)
  • 4 tablets for those >45 kilos or BSA ≥1.7 (or 2 full-strength doses). In ARV-experienced patients with suspected or confirmed loss of sensitivity to LPV, 6 low-dose tablets (or 3 full-strength) may be given.

The package insert information should be consulted for more detailed directions.

Once-daily dosing was attempted in one study in children using a dose of 460mg/m2 lopinavir and 155mg/m2 and this produced similar levels of lopinavir to the 800mg /200mg once-daily dose used in adults. However, given the high variability in LPV drug exposure and trough plasma concentrations amongst individuals, paediatric once-daily dosing is not currently recommended. 2

A number of studies have confirmed that use of the liquid formulation of Kaletra can reduce viral loads in children who have never taken antiretroviral drugs before, as well as those who are ARV-experienced.3 4

The side-effect profile of Kaletra is similar in children and adults.

In the US, Kaletra is one of several recommended first-line PI components in regimens for children. WHO recommends it for use, along with two NRTIs, in infants under 12 months of age who have nevirapine exposure. In children 12 months or older, initial ART with either nevirapine or efavirenz plus two NRTIs is recommended over a PI-based initial regimen.


  1. Panel on antiretroviral therapy and medical management of HIV-infected children Guidelines for the use of antiretroviral agents in pediatric HIV infection. August 16, 2010; pp1-219. Available at (accessed November 13, 2010)., 2010
  2. van der Lee M et al. Pharmacokinetics of a once-daily regimen of lopinavir / ritonavir in HIV-1-infected children. Antivir Ther 11: 439-445, 2006
  3. Saez-Llorens X et al. Forty-eight-week evaluation of lopinavir / ritonavir, a new protease inhibitor, in human immunodeficiency virus-infected children. Pediatr Infect Dis J 22: 216-224, 2003
  4. Resino S et al. Positive virological outcome after lopinavir/ritonavir salvage therapy in protease inhibitor-experienced HIV-1-infected children: a prospective cohort study. J Antimicrob Chemother 54: 921-931, 2004
Community Consensus Statement on Access to HIV Treatment and its Use for Prevention

Together, we can make it happen

We can end HIV soon if people have equal access to HIV drugs as treatment and as PrEP, and have free choice over whether to take them.

Launched today, the Community Consensus Statement is a basic set of principles aimed at making sure that happens.

The Community Consensus Statement is a joint initiative of AVAC, EATG, MSMGF, GNP+, HIV i-Base, the International HIV/AIDS Alliance, ITPC and NAM/aidsmap

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