Trial overview

LEGATO

A Randomized, Double-blind, Phase 3 Study to Evaluate Safety, Reactogenicity, and Immunogenicity of Co-administration of Ad26.COV2.S and Influenza Vaccines in Healthy Adults 18 Years of Age and Older
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The LEGATO study ran from November 2021 until July 2022. 49 people participated.

In this phase 3 study, we investigated the administration of a COVID-19 vaccine (Ad26.COV2.S, Johnson & Johnson) in combination with a flu vaccine. One group received both vaccines on the same day, while the second group had to wait 28 days for the follow-up vaccine.

All participants were over 18 years old, in good general health. They either had not yet received COVID-19 vaccine, or the last dose was administered more than six months ago.

The study compared same-day vaccine administration with administration of both vaccines at 28-day intervals. Participants had to report to the study centre four to five times over a six-month period. In addition, any adverse events were also always followed up by telephone up to a week after each vaccination.

The sponsor of this study was Janssen Vaccines & Prevention B.V. For more scientific background on the study, please visit the official registration database.