Pharmacokinetics of lopinavir/ritonavir crushed versus whole tablets in children

J Acquir Immune Defic Syndr. 2011 Dec 1;58(4):385-91. doi: 10.1097/QAI.0b013e318232b057.


Objective: Lopinavir/ritonavir (Kaletra) is first-line therapy for pediatric HIV infection. In clinical practice, Kaletra tablets are occasionally crushed for pediatric administration. This study compared lopinavir/ritonavir exposure between whole and crushed tablets in HIV-infected children.

Design: This was a randomized, open-label, cross-over study of pediatric patients taking lopinavir/ritonavir as part of their antiretroviral regimen. Each subject had 2 separate (within 30 days) steady-state 12-hour pharmacokinetic (PK) studies with crushed and whole 200/50 mg lopinavir/ritonavir tablets.

Methods: PK blood samples were drawn at 0 (predose), 1, 2, 4, 6, 8, and 12 hours postdose. Lopinavir and ritonavir plasma concentrations measured by high-performance liquid chromatography were used to calculate non-compartmental area under the concentration versus time curve (AUC) and clearance. Wilcoxon signed-rank tests compared PK values between crushed and whole tablets.

Results: Twelve children, median age of 13 years (10-16 years), took 550/138 mg·m(-2) per day lopinavir/ritonavir divided every 12 hours. The median lopinavir AUC after crushed and whole tablets were 92 mg·hr·L(-1) and 144 mg·hr·L(-1), respectively, with an AUC ratio of 0.55 (P = 0.003). Median ritonavir AUC of crushed and whole tablets were 7 mg·hr·L(-1) and 13.3 mg·hr·L(-1), respectively, with an AUC ratio of 0.53 (P = 0.006).

Conclusions: Administration of crushed 200/50 mg lopinavir/ritonavir tablets to children significantly reduced lopinavir and ritonavir exposure with a decrease in AUC by 45% and 47%, respectively. The administration of crushed tablets would require higher doses and therapeutic drug monitoring to ensure adequate lopinavir exposure in patients requiring this practice. The use of crushed lopinavir/ritonavir tablets should be avoided, if possible.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Anti-HIV Agents / administration & dosage
  • Anti-HIV Agents / pharmacokinetics*
  • Child
  • Cross-Over Studies
  • Drug Combinations
  • Female
  • HIV Infections / drug therapy*
  • Humans
  • Lopinavir / administration & dosage
  • Lopinavir / pharmacokinetics*
  • Male
  • Ritonavir / administration & dosage
  • Ritonavir / pharmacokinetics*
  • Tablets
  • Treatment Outcome


  • Anti-HIV Agents
  • Drug Combinations
  • Tablets
  • lopinavir-ritonavir drug combination
  • Lopinavir
  • Ritonavir