Safety and Immunogenicity Study of Tdap Vaccinations for Plasma Donors

A Clinical Study of the Safety and Antibody Responses of Plasma Donors Vaccinated With a Licensed Tdap Vaccine for a Hyperimmunization Program

The goal of this clinical trial is to investigate the safety and tetanus antibody response to a Tdap vaccine in healthy plasma donors. The main question it aims to answer are:

• Is it safe to give this vaccine multiple times over one year to plasma donors since the package insert for this vaccine indicates that it should administered once every 10 years?
• What is the tetanus antibody response over time in these donors after receiving the vaccine multiple times during the study?

Participants will receive a Tdap vaccination every 3 months ±2 weeks for 12 months (5 vaccinations) with a 6 month follow-up after the last vaccination. After obtaining informed consent and screening for eligibility including plasmapheresis donor eligibility, subjects will have other baseline assessments performed and if eligible, will receive the scheduled vaccinations, will be assessed for adverse events (AEs) and have plasma samples collected for antibody titers each month thereafter for 11 months, and then at 1 and 6 months after the last vaccination. As these subjects are participating in a standard donor plasmapheresis donor program, assessments for donor eligibility and routine plasmapheresis will be performed; however, only the data specifically required to meet the objectives of this study will be collected.

Study Overview

• Status: Completed
• Conditions: Tetanus, Diphtheria and Acellular Pertussis Vaccination
• Intervention / Treatment: Biological: Tdap

• Study Type: Interventional
• Enrollment (Actual): 100
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • New Jersey
    • Glassboro, New Jersey, United States, 08028
      • ABO Plasma

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 14 years to 59 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Male or female ages 18 to 63 years
• Females of childbearing potential who agree to employ highly effective birth control measures during the study
• Signed the informed consent form (ICF)
• Met all of the criteria required to be a Normal Source Plasma donor
• Subject is not participating in any other immunization program
• Subject has not had a Tdap vaccination in the last 90 days before the first study vaccination

Exclusion Criteria:

• Subject is pregnant
• Subject has a condition or abnormality that in the opinion of the Investigator would compromise the safety of the subject or the quality of the data
• Subject has repeated reactions or hypersensitivity to components in the vaccine
• Subject has history of a severe reaction to any immunization
• Subject has a history of Guillain-Barré Syndrome
• The Investigator concludes that the anticipated vaccination site (deltoid area) is not suitable for AE assessment

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Tdap for Plasma Donors; Dose: 0.5 mL; Route: Intramuscular (IM) in the deltoid muscle; Frequency: Every 90 days; Duration: 5 doses over 1 year.	Biological: Tdap; Tetanus Toxoid, Reduced Diphtheria Toxoid and Acellular Pertussis Vaccine Adsorbed Suspension manufactured by Sanofi Pasteur; Other Names: Adacel

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Treatment Emergent Adverse Events (TEAEs)	An adverse event (AE) is any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. TEAEs are defined as an adverse event occurring after first study treatment. A serious TEAE was defined as an AE that resulted in any of the following outcomes: death; life-threatening; inpatient hospitalization or prolongation of hospitalization; persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions, an important medical event that based on appropriate medical judgment may jeopardize the subject and may require medical or surgical intervention to prevent one of the aforementioned outcomes.	Up to 18 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Anti-tetanus Antibody Titers in Participants Over Time	Anti-tetanus antibody titer levels after each vaccination presented at geometric means (GeoMean) over time.	Baseline, Month 1, Month 2, Month 3, Month 4, Month 5, Month 6, Month 7, Month 8, Month 9, Month 10, Month 11, Month 12, Month 13, Month 18
Number of Participants With Post Vaccination Anti-tetanus Antibody Range Levels	The numbers and percentages of participants whose post vaccination antibody levels were <5 IU/mL; ≥5 IU/mL to 10 IU/mL; >10 IU/mL to 15 IU/mL; and, >15 IU/mL after each vaccination.	Baseline, Month 1, Month 2, Month 3, Month 4, Month 5, Month 6, Month 7, Month 8, Month 9, Month 10, Month 11, Month 12, Month 13, Month 18

Collaborators and Investigators

• Sponsor: ABO Holdings, Inc.
• Investigators: Principal Investigator: Adam Thaler, DO, Center Medical Director

Study record dates

Study Major Dates

• Study Start (Actual): May 5, 2023
• Primary Completion (Actual): May 12, 2025
• Study Completion (Actual): May 12, 2025

Study Registration Dates

• First Submitted: December 15, 2022
• First Submitted That Met QC Criteria: December 21, 2022
• First Posted (Actual): December 23, 2022

Study Record Updates

• Last Update Posted (Actual): June 27, 2025
• Last Update Submitted That Met QC Criteria: June 24, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: Plasma; Tetanus; Immunoglobulin; Plasma Donor; Plasma Donation; Hyperimmunization
• Additional Relevant MeSH Terms: Infections; Gram-Positive Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Actinomycetales Infections; Clostridium Infections; Corynebacterium Infections; Diphtheria; Tetanus
• Other Study ID Numbers: ABO-TET-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No