NCT07312851

A Study to Investigate Andexanet Dosing and the Interaction Between Andexanet and Subsequent Enoxaparin in Healthy Participants

A Phase I, Randomized, Single-blind, Placebo-controlled Study to Further Characterize Andexanet Posology and Assess the Interaction Between Andexanet and Subsequent Enoxaparin in Healthy Participants

• Status: Recruiting
• Phase: Phase 1
• Study type: Interventional
• Enrollment: 186 (estimated)
• Sponsor: AstraZeneca · Industry
• Sex: All
• Age: 18 Years – 55 Years
• Healthy volunteers: Accepted

Summary

The purpose of this study is to characterize andexanet posology and interaction between andexanet and enoxaparin post infusion in healthy participants.

Detailed description

This is a single-blind, placebo-controlled study. The study has 4 modules, which is then divided into 2 parts. Part A of the study will focus on further characterization of andexanet posology and Part B of the study will evaluate a re-institution of anticoagulation with enoxaparin. Module 1, 2 and 4 - rivaroxaban, apixaban and enoxaparin: These modules are designed to determine the pharmacodynamic (PD) effect of andexanet by assessing its reversal effects on rivaroxaban and apixaban anticoagulation, or assessing its effects in the absence of anticoagulants, and to identify the time interval after andexanet administration at which andexanet shows no impact on enoxaparin. Module 3 - rivaroxaban and apixaban: This Module is designed to determine the PD effect of bolus only andexanet by assessing its reversal effect on rivaroxaban and apixaban anticoagulation. All the Modules will comprise: * A Screening/Enrollment Period of maximum 28 days. * An in-house stay comprising of a safety baseline lab period (Day -3 to Day -1) * Treatment period (Day 1 to Day 2) * Safety follow-up period (Day 3 to Day 5) * A final Follow-up Visit within 30 days (+7 days) after the last andexanet/placebo administration.

Conditions

• Healthy Participants

Interventions

Type	Name	Description
DRUG	Andexanet alfa	Andexanet alfa will be administered as an intravenous bolus followed by an infusion, however, in Module 3, only a bolus will be given.
DRUG	Rivaroxaban	Rivaroxaban will be administered as an oral tablet.
DRUG	Apixaban	Apixaban will be administered as an oral tablet.
DRUG	Enoxaparin	Enoxaparin will be administered as a subcutaneous injection.
OTHER	Placebo	Placebo will replace andexanet and be given as an IV bolus plus infusion in Modules 1 and 2; in Module 3, placebo will be IV bolus only. In Module 4, an oral placebo tablet will replace rivaroxaban and apixaban.

Timeline

• Start date: 2026-01-19
• Primary completion: 2026-06-19
• Completion: 2026-06-19
• First posted: 2025-12-31
• Last updated: 2026-02-24

Locations

2 sites across 2 countries: Germany, United Kingdom