Tenofovir Disoproxil Fumarate + Efavirenz = Unknown or no reaction

Effect on Concentration

Tenofovir Disoproxil Fumarate
No change
Applies within class?
No
Efavirenz
No change
Applies within class?
No

Pharmacologic Effects

Tenofovir Disoproxil Fumarate
Effect
N/A
Applies within class?
No
Efavirenz
Effect
N/A
Applies within class?
No

Interaction History

N/A

Last Updated 19-Jul-2018

Summary

Sources

Tenofovir Disoproxil Fumarate versus Efavirenz ^

Study Design

In a study by Droste, et al, the combination of nevirapine 200 mg BID with tenofovir DF 300 mg daily, nevirapine 400 mg daily with tenofovir DF 300 mg daily were compared to nevirapine 200 mg BID or nevirapine 400 mg daily when administered alone in HIV infected patients. Further the combination of efavirenz 600 mg daily with tenofovir DF 300 mg was compared with efavirenz 600 mg daily when given alone.

Study Results

In the study by Droste, et al, the addition of tenofovir DF to efavirenz or nevirapine in HIV-infected patients does not influence the plasma levels of nevirapine or efavirenz. Furthermore, nevirapine and efavirenz do not have an effect on tenofovir plasma levels and tenofovir concentration ratios.

Study Conclusions

The author concluded that either nevirapine or efavirenz could be coadministred with tenofovir DF in HIV-infected patients without dose modifications.

References

Droste JA, Kearney BP, Hekster YA, Burger DM. Assessment of drug-drug interactions between tenofovir disoproxil fumarate and the nonnucleoside reverse transcriptase inhibitors nevirapine and efavirenz in hiv-infected patients. Journal Of Acquired Immunodeficiency Syndromes. 2006; 1: 37-43.