Many plasma donation centers have Tetanus immunization programs that are implemented in order to collect plasma with high levels of tetanus antibodies. The immunization program requires participants to receive multiple tetanus vaccinations over a period of time with the goal of hyper-immunizing them to tetanus. Their antibody-rich plasma is then used to manufacture a tetanus immunoglobulin product which helps with the prophylaxis and treatment of tetanus disease.

The Tetanus vaccine previously used for these programs is no longer being manufactured. Therefore, we must evaluate the safety and efficacy of a different vaccine when used for this purpose. The only other FDA approved Tetanus vaccines currently available for adults in the US are combination vaccines that also immunize against Diphtheria and/or Pertussis.

In this study, the investigators will evaluate two vaccines that are combinations of Tetanus and Diphtheria (Td). Investigators will not evaluate any vaccines containing Pertussis antigen. The vaccines to be evaluated are manufactured by MassBiologics and Sanofi Pasteur (Tenivac).

The package insert for these vaccines indicates they should be administered to previously vaccinated people once every 10 years. However, this study will evaluate whether they are safe and effective for dosing every 90 days.

The investigators hypothesize that at least 25% of study subjects will have a positive response to at least one of the five planned doses. Each vaccine will be evaluated separately.

Inclusion Criteria:

1. Male or female ≥18* years of age at Visit 1.
2. Subject has met all suitability criteria that would allow donation as a Normal Source Plasma donor
3. Subject has not been immunized for tetanus within the prior three (3) months
4. Subject is not participating in any other immunization program
5. Subject possesses a pre-existing antibody for tetanus of at least 0.15 IU/mL

Exclusion Criteria:

1. Pregnant.

2. Presence of a condition or abnormality that in the opinion of the Investigator would compromise the safety of the patient or the quality of the data.

3. Subject has a hypersensitivity to components in the vaccine (e.g., thimerosal, latex, etc.)

4. Subject has history of a severe reaction to any immunization

5. Subject has a history of Guillain-Barré Syndrome

6. Subject is unable to read and/or write due to illiteracy or a physical impairment.

7. The Investigator concludes that the anticipated vaccination site (deltoid area) is not suitable for adverse event assessment

   • Or legal adult according to local law. Participants in NE limited to individuals age 19-69 years due to age of majority laws in NE.