Raltegravir + Ritonavir = Precautionary

Effect on Concentration

Raltegravir
No change
Applies within class?
No
Ritonavir
Unknown
Applies within class?
No

Pharmacologic Effects

Raltegravir
Effect
N/A
Applies within class?
No
Ritonavir
Effect
N/A
Applies within class?
No

Interaction History

N/A

Last Updated 22-Nov-2022

Summary

Sources

Raltegravir vs efavirenz or ritonavir ^

Study Design

14 male, HIV-negative healthy subjects were administered a single dose of raltegravir 400 mg followed by a 4-day or longer washout interval (Period 1). Ritonavir 100 mg was then administered twice daily for 16 days (Period 2). A single dose of raltegravir 400 mg was administered with the morning dose of ritonavir on day 14 of period 2. Raltegravir PK sampling occurred 16 times over 48 hours beginning with each raltegravir dose.All doses were administered with a moderate-fat meal, as is recommended with ritonavir. Raltegravir doses were placebo-controlled, and ritonavir was administered open-label.

Study Results

Raltegravir Cmin was similar regardless of ritonavir exposure. Raltegravir AUC was 16% lower in the presence of ritonavir (p=0.122) and raltegravir Cmax was decreased 24% with ritonavir (p=0.143). No statistically significant changes in raltegravir PK parameters were observed in the study, including Tmax and half-life.

Study Conclusions

References

Marian Iwamoto, Larissa A Wenning, Amelia S Petry, Martine Laethem, Marina De_Smet, James T Kost, Sheila A Breidinger, et al. Minimal effects of ritonavir and efavirenz on the pharmacokinetics of raltegravir. Antimicrobial Agents And Chemotherapy. 2008; 12: 4338-4343.