Emtricitabine/Tenofovir Disoproxil Fumarate + oestradiol valerate = Unknown or no reaction

Effect on Concentration

Emtricitabine/Tenofovir Disoproxil Fumarate
Increase
Applies within class?
No
oestradiol valerate
Unknown
Applies within class?
No

Pharmacologic Effects

Emtricitabine/Tenofovir Disoproxil Fumarate
Effect
N/A
Applies within class?
No
oestradiol valerate
Effect
N/A
Applies within class?
No

Interaction History

N/A

Last Updated 18-Nov-2022

Summary

Some studies suggest that feminizing hormone therapy (FHT) reduces the efficacy of PrEP among transgender women (TGW), which would limit the benefit of PrEP for this population. The authors of this study aimed to evaluate the impact of FHT on tenofovir disoproxil fumarate/emtricitabine pharmacokinetics (PK) among TGW in the context of the PrEParadas demonstration study.

Sources

Impact of feminizing hormone therapy on tenofovir and emtricitabine plasma pharmacokinetics: a nested drugdrug interaction study in a cohort of Brazilian transgender women using HIV pre-exposure prophylaxis ^

Study Design

PK substudy of the effects of feminizing hormone therapy (FHT) on tenofovir disoproxil fumarate/emtricitabine nested to a trans-specific PrEP demonstration study (NCT03220152). Participants were assigned to receive PrEP only (noFHT) or standardized FHT (sFHT; oestradiol valerate 26&8197;mg plus spironolactone 100300&8197;mg) plus PrEP for 12&8197;weeks, after which they could start any FHT (aFHT). Non-compartmental PK parameters of tenofovir and emtricitabine were compared as geometric mean ratios (GMRs) between noFHT and PrEP and FHT (sFHT at short-term PK; aFHT at long-term PK) participants.

Study Results

When comparing PK parameters between the short-term PK of noFHT (n12) and sFHT participants (n18), the only observably different PK parameter was emtricitabine Cmax (1656 ng/mL in the noFHT group vs 1911 ng/mL in the sFHT group; GMR: 1.15 95 CI: 1.011.32). No differences in PK parameters were detected between the noFHT short-term PK group compared to the aFHT long-term PK group.

Study Conclusions

Results of this study indicate no interaction of feminizing hormone therapy (FHT) on tenofovir levels, further supporting PrEP use among transgender women using FHT.

References

Cattani, V, Jalil, E, Eksterman, L, Torres, T, Cardoso, S, Castro, C, Monteiro, L, Wilson, E, Bushman, L, Anderson, P, Veloso, V, Grinsztejn, B, Estrela, R. Impact of feminizing hormone therapy on tenofovir and emtricitabine plasma pharmacokinetics: a nested drug-drug interaction study in a cohort of brazilian transgender women using hiv pre-exposure prop. Journal Of Antimicrobial Chemotherapy. 2022; 10: 2729-2736.