Drug Interaction With Envarsus XR and Grapefruit Juice

Assessment of the Intestinal CYP3A Contribution to Drug Interactions With Envarsus XR Using Grapefruit Juice

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT03916380

Enrollment

Registered

2019-04-16

Start date

2019-10-25

Completion date

2023-12-31

Last updated

2025-04-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Kidney Transplant; Complications, Drug Interaction Food

Keywords

Tacrolimus, Grapefruit Juice, CYP3A4, Midazolam, Kidney Transplant

Brief summary

Transplant patients must take lifelong immunosuppression in order to prevent rejection of their organ. Tacrolimus is the most widely used immnosuppressive agent. Part of the routine education given to patients regarding tacrolimus is that they must avoid many drugs and substances that can interact with tacrolimus so that they don't experience side effects or lack of effect. Patients are told they must avoid readily available substances such as grapefruit juice and St. John's wort. A new once daily formulation of tacrolimus, Envarsus XR, may bypass the place in the gut in which many of these drug interactions occur. We will give kidney transplant patients Envarsus with and without grapefruit juice and measure the effect on blood levels throughout the day. Results from this study will also give us information about the likelihood of other drugs interacting with Envarsus XR.

Interventions

DIETARY_SUPPLEMENTGrapefruit Juice

Single 8 ounce administration of oral grapefruit juice

Study design

Observational model

OTHER

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

* Primary Kidney Transplant Age \> 18 years At least 3 months post-transplantation Taking a stable dose of tacrolimus extended release with a target trough of 8-10 ng/mL BMI between 18-32

Exclusion criteria

* Multi-organ transplant Concomitant use of mTOR inhibitor Concomitant use of belatacept Concomitant use of medication affecting CYP3A or P-gp History of rejection Hypersensitivity to midazolam Hypersensitivity to Envarsus Active diarrhea or constipation BMI \< 18 or \> 32

Design outcomes

Primary

Measure	Time frame
Tacrolimus AUC before and after Grapefruit Juice	2-4 weeks

Secondary

Measure	Time frame
Tacrolimus AUC compared to Midazolam AUC	2-4 weeks

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026