The purpose of this study was to demonstrate that V181 is safe and well tolerated and elicits an immune response that is non-inferior to that of Butantan - DV at Day 28 post-vaccination in adults 18 to 50 years of age in Brazil. The primary hypothesis was that V181 is non-inferior to Butantan - DV for each of the 4 dengue serotypes based on geometric mean titers (GMTs) and seroconversion rates at Day 28 post-vaccination.

Inclusion Criteria:

• Male participants were eligible to participate if they agreed to the following for at least 90 days after administration of study intervention:

  • Abstained from heterosexual intercourse as their preferred and usual lifestyle (abstinent on a long term and persistent basis) and agreed to remain abstinent; or agreed to use contraception unless confirmed to be azoospermic (vasectomized or secondary to medical cause).

• A female participant was eligible to participate if she was not pregnant or breastfeeding, and at least one of the following conditions applies:

  • was NOT a woman of child-bearing potential (WOCBP); or
  • was a WOCBP and using a contraceptive a highly effective method (with a failure rate of <1% per year), or
  • was abstinent from heterosexual intercourse as her preferred and usual lifestyle (abstinent on a long term and persistent basis), for at least 90 days after administration of study intervention.
  • Had a negative highly sensitive pregnancy test (urine or serum, as required by local regulations) before administration of study intervention

• Were dengue seronegative based on a pre-vaccination point of care (POC) dengue test.

Exclusion Criteria:

• Had a known history of dengue or Zika natural infection.
• Had an acute febrile illness (axillary temperature ≥37.8°C) occurring within 72 hours prior to receipt of study vaccine.
• Had a known hypersensitivity or history of severe allergic reaction (eg, swelling of the mouth and throat, difficulty breathing, hypotension or shock) to any component of the dengue vaccine, that required medical intervention.
• Had a serious or progressive disease, including but not limited to cancer, uncontrolled diabetes, severe cardiac, renal or hepatic insufficiency, systemic autoimmune or neurologic disorder.
• Had known or suspected impairment of immunological function, including but not limited to congenital or acquired immunodeficiency, human immunodeficiency virus (HIV) infection, hematologic malignancy, or treatment for autoimmune diseases.
• Had a condition in which repeated venipuncture or injections pose more than minimal risk, such as hemophilia, thrombocytopenia, other severe coagulation disorders, or significantly impaired venous access
• Had received a dose of any dengue vaccine (investigational or approved) prior to study entry or plans to receive any dengue vaccine (investigational or approved) for trial duration.
• Had received a licensed non-live vaccine within 14 days before receipt of study vaccine or was scheduled to receive any licensed non-live vaccine within 28 days following receipt of study vaccine. Exception: Inactivated influenza vaccine might be administered, but given at least 7 days before receipt of study vaccine or at least 28 days after receipt of study vaccine.
• Had received a licensed live vaccine within 28 days prior to receipt of study vaccine or was scheduled to receive any live vaccine within 28 days following receipt of study vaccine.
• Had received systemic corticosteroids (equivalent of ≥2 mg/kg/day of prednisone or ≥20 mg/day for persons weighing >10 kg) for ≥14 consecutive days and had not completed treatment at least 30 days before study entry or was expected to receive systemic corticosteroids at aforementioned dose and duration within 28 days following receipt of study vaccine. (Note: topical and inhaled/nebulized steroids were permitted.)
• Had received systemic corticosteroids exceeding physiologic replacement doses (approximately 5 mg/day prednisone equivalent) within 14 days before vaccination.
• Had received immunosuppressive therapies, including chemotherapeutic agents used to treat cancer or other conditions, treatments associated with organ or bone marrow transplantation, or autoimmune disease, within 6 months prior to receipt of study vaccine, or plans to receive immunosuppressive therapies within 28 days following receipt of study vaccine.
• Had received a blood transfusion or blood products (including immunoglobulins) within 6 months prior to receipt of study vaccine or plans to receive a blood transfusion or blood products (including immunoglobulins) within 28 days following receipt of study vaccine.
• Had planned donation of blood, eggs, or sperm at any time from signing the informed consent through 90 days post-vaccination.

https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf