Study Evaluating the Safety of a Recombinant Acellular Pertussis Vaccine in Adults

This is a pivotal, multi-site, observer-blind, randomized, active-controlled vaccine trial in which 2400 healthy adults aged 18 to 75 years will be recruited at approximately 7:1 ratio from three sites in Bangkok, Thailand. As the aim of this trial is to extend the safety database for recombinant acellular pertussis (aP) vaccine in a larger population of adults, the active-controlled arm is added mainly to reduce selection and measurement bias through randomization and blinding methods.

Inclusion criteria

• An adult participant will be eligible for inclusion if ALL of the following criteria are met at the time of screening:

• Aged 18 to 75 years (less than 76 years full of age) on the day of inclusion;
• Can provide written informed consent;
• Healthy, as established by pertinent medical history and physical examination;
• Capable of complying with the study protocol and procedures;
• For women with childbearing potential (i.e., urine pregnancy test will not be performed in females who have undergone sterilization, hysterectomy or who are post-menopausal.), must have a negative urine pregnancy test at enrollment.

Exclusion criteria

• A participant with ANY of the following criteria at study entry will not be eligible for participation:

• History of significant medical illness such as but not limited to immune deficiency, clinically significant psychiatric, hematologic, pulmonary, cardiovascular, or hepatic, renal, splenic or thymic functional abnormality as determined by the investigator based on medical history and physical examination. For those cases that are clinically stable, the investigator may include them as deemed per medical judgement.
• Breastfeeding women or female participants who intend to become pregnant during the study period;
• History of a severe allergic reaction to any vaccine (including its components);
• History of serious adverse event or neurological adverse event to any vaccination;
• Receipt of any investigational product or licensed vaccine within 30 days prior to enrollment (3 months for live-attenuated vaccines);
• Plan to receive tetanus, diphtheria or pertussis vaccine or plan to participate in other clinical trial during the study period;
• Having experienced physician-diagnosed pertussis within 5 year prior to enrollment;
• Receipt of diphtheria or tetanus or pertussis vaccine within 5 years prior to enrollment;
• Having any progressive or severe neurologic disorder, seizure disorder or recent history of Guillain-Barré syndrome;
• Medically significant cancer (except for benign or localized skin cancer, cancer in remission for ≥10 years);
• A known bleeding diathesis or any condition that may be associated with a prolonged bleeding time resulting in a problem with intramuscular injection;
• Suspected or known alcoholism and/or illicit drug abuse within the past 5 years;
• Administration of immunoglobulins and/or any blood products within 3 months preceding study entry or planned administration during the study period;
• History of receiving immunosuppressive drugs or systemic corticosteroid (>0.5 mg/kg of prednisolone or equivalent for more than 14 days) within 3 months prior to study entry;
• Has any active clinically significant finding or life-threatening disease that, in the opinion of the investigator, would increase the risk of the individual's having an adverse outcome by participating in this study.