Safety and Immunogenicity of Different Formulations of a Tetravalent Dengue Purified Inactivated Vaccine in Healthy Adults from Puerto Rico: Final Results after 3 Years of Follow-Up from a Randomized, Placebo-Controlled Phase I Study

Am J Trop Med Hyg. 2020 May;102(5):951-954. doi: 10.4269/ajtmh.19-0461.


Four formulations of an investigational tetravalent dengue purified inactivated vaccine, administered as two doses one month (M) apart, were previously shown to be immunogenic and well-tolerated up to M13 of the phase I study NCT01702857. Here, we report results of the follow-up from M14 to year (Y) 3. One hundred healthy Puerto Rican adults, predominantly dengue virus (DENV)-primed, were randomized 1:1:1:1:1 to receive placebo or vaccine formulations: 1 μg/serotype/dose adjuvanted with aluminum, AS01E or AS03B, or aluminum-adjuvanted 4 μg/serotype/dose. No serious adverse events occurred. Two medically-attended potential immune-mediated disease cases, vaccination unrelated, were reported (groups 1 µg+Alum and 1 µg+AS03B). Of 14 instances of suspected dengue, none were laboratory confirmed. Geometric mean neutralizing antibody titers against DENV 1-4 waned from M14, but remained above pre-vaccination levels for DENV 1-3, with the highest values for group 1 µg+AS03B: 1220.1, 920.5, 819.4, and 940.5 (Y2), and 1329.3, 1169.2, 1219.8, and 718.9 (Y3). All formulations appeared to be safe and immunogenic during the 3-year follow-up.

Publication types

  • Clinical Trial, Phase I
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Antibodies, Neutralizing / immunology
  • Antibodies, Viral / immunology
  • Dengue / prevention & control*
  • Dengue Vaccines / administration & dosage
  • Dengue Vaccines / adverse effects
  • Dengue Vaccines / immunology
  • Dengue Vaccines / therapeutic use*
  • Dengue Virus / immunology*
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Puerto Rico


  • Antibodies, Neutralizing
  • Antibodies, Viral
  • Dengue Vaccines