Nevirapine + Itraconazole = Precautionary

Effect on Concentration

Nevirapine
No change
Applies within class?
No
Itraconazole
Decrease
Applies within class?
No

Pharmacologic Effects

Nevirapine
Effect
N/A
Applies within class?
No
Itraconazole
Effect
N/A
Applies within class?
No

Interaction History

N/A

Last Updated 30-Jul-2018

Summary

Sources

Nevirapine versus Itraconzole ^

Study Design

Our study was conducted in 12 healthy volunteers in two phases. In phase 1 (from days 1–28), all subjects were randomly assigned to a two-way crossover study of a nevirapine regimen (nevirapine 200 mg once daily for 7 days) and an itraconazole regimen (itraconazole 200 mg once daily for 7 days) with a 14-day wash-out period between. Phase 2 (from days 43–49) was performed 14 days after phase 1 ended, and all subjects received a combination regimen (nevirapine 200 mg combined with itraconazole 200 mg once daily for 7 days). Nevirapine pharmacokinetic studies were carried out starting with the seventh dose of nevirapine in the nevirapine regimen (on days 7–10 or 28–31) and the combination regimen (on days 49–52). Itraconazole pharmacokinetic studies were carried out starting with the seventh dose of itraconazole in the itraconazole regimen (on days 7–10 or 28–31) and the combination regimen (on days 49–52).

Study Results

There was no significant difference in nevirapine pharmacokinetic parameters between the nevirapine and combination regimens. Itraconazole plasma concentrations were lower when it was administered in the combination regimen than when it was administered in the itraconazole regimen. The mean Cmax, AUC0–96 and t 1/2 of itraconazole were significantly reduced by 38, 61 and 31%, respectively.

Study Conclusions

Nevirapine had a strong inducing effect on the metabolism of itraconazole, but there was no significant effect of itraconazole on the pharmacokinetics of nevirapine. However, a higher daily dosage of itraconazole might have an inhibitory effect.

References

Jaruratanasirikul S, Sriwiriyajan S. Pharmacokinetic study of the interaction between itraconazole and nevirapine. european journal of clinical pharmacology. European Journal Of Clinical Pharmacology. 2007; 5: 451-456.