Assessment of Gastrointestinal Blood Loss After Receiving Aspirin or Aspirin Plus Rivaroxaban, or Aspirin Plus REGN9933, or Aspirin Plus REGN7508 in Healthy Adult Participants

NCT06444178 | Completed Phase 1 FDA Drug

• 1 other identifier: R9933-HV-2424
• Study Type: interventional
• Target: 224
• Locations: 1 country
• Sites: 1

Brief Summary

This study is researching experimental drugs called REGN9933 and REGN7508 (called "study drugs") and comparing their effects to approved treatments of rivaroxaban and aspirin (called "standard treatments"). Aspirin will be given alone or in combination with the study drugs or the other standard treatments to look at their effects on blood loss in the intestines. The aim of the study is to see if aspirin alone or the study drugs REGN9933 and REGN7508, when taken with aspirin, cause less minor intestinal bleeding than standard treatments rivaroxaban with aspirin. The study is looking at several other research questions, including:

• What side effects may happen from taking the study drug
• How much study drug is in the blood at different times
• Whether the body makes antibodies against the study drug (which could make the drug less effective or could lead to side effects)

Conditions

Healthy Volunteers

Keywords

Gastrointestinal (GI) bleeding; Fecal occult blood testing (FOBT)

Outcome Measures

Primary Outcomes (1)

• Change in fecal hemoglobin content (FHC)

  Baseline and up to day 22

Secondary Outcomes (12)

• Incidence of treatment-emergent adverse events (TEAE)

  Up to day 100

• Severity of TEAE

  Up to day 100

• Incidence of major bleeding

  Up to day 100

• Incidence of clinically relevant non-major (CRNM) bleeding

  Up to day 100

• Concentrations of REGN9933

  Up to day 29

Study Arms (4)

Arm 1: Aspirin

ACTIVE COMPARATOR

Randomized 1:1:1:1

Drug: Aspirin

Arm 2: Aspirin + REGN9933

EXPERIMENTAL

Randomized 1:1:1:1

Drug: Aspirin; Drug: REGN9933

Arm 3: Aspirin + REGN7508

EXPERIMENTAL

Randomized 1:1:1:1

Drug: Aspirin; Drug: REGN7508

Arm 4: Aspirin + Rivaroxaban

ACTIVE COMPARATOR

Randomized 1:1:1:1

Drug: Aspirin; Drug: Rivaroxaban

Interventions

Aspirin DRUG

Oral administration

Arm 1: Aspirin; Arm 2: Aspirin + REGN9933; Arm 3: Aspirin + REGN7508; Arm 4: Aspirin + Rivaroxaban

REGN9933 DRUG

Administered intravenous (IV)

Arm 2: Aspirin + REGN9933

REGN7508 DRUG

Administered IV

Arm 3: Aspirin + REGN7508

Rivaroxaban DRUG

Oral administration

Arm 4: Aspirin + Rivaroxaban

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Body mass index between 18.0 and 32.5 kg/m2 (inclusive) at the screening visit
• Judged by the investigator to be in good health based on medical history, physical examination, vital sign measurements, and electrocardiograms (ECGs) performed at screening and/or prior to administration of initial dose of study treatment
• Normal aPTT, normal PT, and normal platelet counts at screening period and at the day 1 visit as defined by the local laboratory
• Hemoglobin values within the normal range, per local laboratory, at the screening and day 1 visits
• Negative FOBT at Baseline (visit 2) and visit 3 as defined in the protocol

You may not qualify if:

• History of any major surgical procedure or clinically significant physical trauma in the last 6 months, in the opinion of the investigator, that may pose a risk to the participant by study participation
• Whole blood donation within the previous 56 days or plasma donation within the previous 7 days prior to the screening visit
• Hospitalized for any reason within 30 days of the screening visit
• Estimated glomerular filtrate rate (eGFR) of \<60 mL/min/1.73m2 at screening as described in the protocol.
• Current smoker or former smoker, including e-cigarettes, who stopped smoking within 12 months prior to the screening visit
• History of illicit drug or alcohol abuse within the last 2 years prior to the day 1 visit
• Use of any prescription and nonprescription medications or nutritional supplements from approximately 2 weeks or 5 half-lives, as described in protocol
• Has elective surgery planned to occur prior to end of study (EOS)

Sponsors & Collaborators

• Regeneron Pharmaceuticals: lead

Study Sites (1)

Fortrea Clinical Development

Leeds, LS11 9EH, United Kingdom

Location

MeSH Terms

Conditions

Hemorrhage

Interventions

Aspirin; Rivaroxaban

Condition Hierarchy (Ancestors)

Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Salicylates; Hydroxybenzoates; Phenols; Benzene Derivatives; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Thiophenes; Sulfur Compounds; Morpholines; Oxazines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds

Study Officials

• Clinical Trial Management

  Regeneron Pharmaceuticals

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 30, 2024
• First Posted: June 5, 2024
• Study Start: September 30, 2024
• Primary Completion: April 7, 2025
• Study Completion: July 9, 2025
• Last Updated: July 16, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR, ANALYTIC CODE
• Time Frame: When Regeneron has: * received marketing authorization from major health authorities (e.g., FDA, European Medicines Agency (EMA), Pharmaceuticals and Medical Devices Agency (PMDA), etc.) for the product and indication or has globally discontinued development of the product for all indications on or after April 2020 and has no plans for future development * made results publicly available (e.g., scientific publication, scientific conference, clinical trial registry) * the legal authority to share the data, and * ensured the ability to protect participant privacy
• Access Criteria: Qualified researchers can submit a proposal for access to individual patient or aggregate level data from a Regeneron-sponsored clinical trial through Vivli. Regeneron's Independent Research Request Evaluation Criteria can be found at: https://www.regeneron.com/sites/default/files/Regeneron-External-Data-Sharing-Policy-and-Independent-Research-Request-Evaluation-Criteria.pdf

Locations

GB (1)