Safety and Immunogenicity Study of a Multivalent Gonorrhoea Vaccine

LTB-NG6 is a vaccine including 6 N. gonorrhoeae antigens. During the study, healthy adults will be randomized to receive 1 of 5 different vaccine doses, or a placebo.

Participants will receive a 2-dose schedule.

Inclusion criteria

• Aged 18-50 years (inclusive) at the time of the first injection
• Good and stable general health, determined by medical history, laboratory findings and physical examination as judged by the Investigator before receiving the first injection.
• Willingness and ability to comply with the requirements of the protocol (e.g., completion of the diary forms, return for follow-up visits)
• Signed written informed consent obtained
• Availability for the trial duration, including all planned follow-up visits and phone calls
• Negative urine pregnancy test for WOCBP. WOCBP must be willing to use a highly effective method of contraception during the trial

Exclusion criteria

• Health conditions that, in the opinion of the Investigator, may interfere with optimal participation in the trial or place the participant at increased risk of adverse events
• Acute or active infectious disease (including symptomatic sexually transmitted infections or any other ongoing acute infections), fever (oral temperature ≥38.0°C), or acute illness at the time of enrollment.
• History of gonorrhea at any time (either self-reported or medically confirmed) or confirmed at screening by a positive nucleic acid amplification test (NAAT) result for Neisseria gonorrhoeae
• History of prior confirmed N. meningitidis infection
• Previous vaccination with Bexsero or any meningococcal serogroup B vaccine (including self-report)
• Any deviation from the normal range in biochemistry or hematology blood tests clinically significant in the opinion of the Investigator, measured at the screening visit
• Clinical conditions representing contraindication to intramuscular vaccination and blood draws (e.g., coagulation disorder)
• Known or suspected impairment of immunological function (e.g., documented HIV infection, asplenia/splenectomy, or history of autoimmune disease or lymphoproliferative disorder)
• Positive test for active HBV infection (positive HBsAG test), any HCV infection (positive HCV antibody test), or any HIV-1/2 infection
• Planned or actual administration of any licensed vaccine within 14 days prior to enrollment. Note: In case an emergency mass vaccination for an unforeseen public health threat (e.g., a pandemic) is organized by the public health authorities, the time period described above can be reduced, if necessary, for that vaccine, provided that it is licensed or authorized and that it is used according to the local governmental recommendations, and provided that a written approval from the Sponsor is obtained
• Body Mass Index (BMI) ≤19 or ≥35
• History of systemic administration of corticosteroids (PO/IV/IM) within the last month prior to injection or for more than 14 consecutive days within 3 months prior to injection (i.e., prednisone or equivalent ≥20 mg/day). Inhaled and topical steroids are allowed
• Administration of antineoplastic, immune-modulating, immunosuppressive agents or chemotherapy within 3 months prior to injection
• Suspected or known hypersensitivity (including allergy) to any of the vaccine components or medical equipment whose use is foreseen in this trial
• Concurrently participating in another clinical trial or planned participation at any time during the trial period, in which the participant has been or will be exposed to an investigational or a non-investigational interventional vaccine/product (pharmaceutical product)
• History of any chronic or progressive disease that according to judgment of the Investigator could interfere with the trial outcomes or pose a threat to the participant's health
• Received an investigational or non-registered product (medicinal drug or vaccine), within 3 months prior to enrollment or planned use during the trial period
• Administration of immunoglobulin and/or any blood products within the three months prior to enrollment
• Blood donation equal or greater to 500 mL of blood drawn within 3 months prior to enrollment
• Participants with an elective surgical intervention, planned during the trial period until one month after second injection
• Female participants lactating, pregnant, or intending to become pregnant as reported by the participant