Article

Influence of antiretroviral drugs on the pharmacokinetics of prednisolone in HIV-infected individuals.

Pharmacy Department, Warren G Magnuson Clinical Center, National Institutes of Health, Bethesda, MD, USA.
JAIDS Journal of Acquired Immune Deficiency Syndromes (impact factor: 4.43). 08/2008; 48(5):561-6. DOI:10.1097/QAI.0b013e31817bebeb pp.561-6
Source: PubMed

ABSTRACT Corticosteroids are cytochrome P450 3A4 substrates, which have been associated with toxicities in patients receiving cytochrome P450 3A4 inhibitors such as human immunodeficiency virus protease inhibitors. In a study in healthy volunteers, ritonavir significantly increased prednisolone exposure.
We investigated the influence of antiretroviral (ARV) medications on prednisolone pharmacokinetics in 3 groups of 10 human immunodeficiency virus-infected subjects. One group received lopinavir/ritonavir, and another efavirenz, as part of their ARV regimen; a third group did not receive ARV medications. Each subject received a single 20-mg prednisone dose followed by serial blood sampling for prednisolone. Prednisolone pharmacokinetics were compared among the groups.
Area under the concentration-time curve was significantly lower in efavirenz recipients versus subjects receiving lopinavir/ritonavir (geometric mean ratio = 0.60, P = 0.01). Average prednisolone area under the concentration-time curve was higher in subjects taking lopinavir/ritonavir versus subjects not on ARVs; however, this difference was not significant (P > 0.05).
These data indicate that prednisolone concentrations may fluctuate widely when human immunodeficiency virus-positive individuals established on efavirenz therapy change to lopinavir/ritonavir or vice versa.

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

10 human immunodeficiency virus-infected subjects
 
3 groups
 
ARV medications
 
ARV regimen
 
concentration-time curve
 
Corticosteroids
 
cytochrome P450 3A4 inhibitors
 
efavirenz
 
efavirenz recipients
 
efavirenz therapy change
 
healthy volunteers
 
human immunodeficiency virus protease inhibitors
 
human immunodeficiency virus-positive individuals
 
prednisolone
 
prednisolone concentrations
 
prednisolone exposure
 
Prednisolone pharmacokinetics
 
ritonavir
 
serial blood sampling
 
single 20-mg prednisone dose