Immunogenicity of Fractional One-fifth and One-half Doses of Yellow Fever Vaccine Compared to Full Dose in Children 9-23 Months Old

Summary

A randomized clinical trial comparing fractional dose Yellow Fever vaccination to the full dose among children aged 9-23 months in Uganda. Children will have immune response assessed at baseline, 4 weeks, and 12 months after vaccination. Enrolled participants will be randomized to one of three arms: A. One-fifth fractional dose (0.1 ml) administered subcutaneously B. One-half fractional dose (0.25 ml) administered subcutaneously C. Full dose (0.5 ml) administered subcutaneously

Timeline

Start

2018-11-01

Primary completion

2021-09-01

Completion

2021-09-01

Publications

• Background Casey RM, Harris JB, Ahuka-Mundeke S, Dixon MG, Kizito GM, Nsele PM, Umutesi G, Laven J, Kosoy O, Paluku G, Gueye AS, Hyde TB, Ewetola R, Sheria GKM, Muyembe-Tamfum JJ, Staples JE. Immunogenicity of Fractional-Dose Vaccine during a Yellow Fever Outbreak - Final Report. N Engl J Med. 2019 Aug 1;381(5):444-454. doi: 10.1056/NEJMoa1710430. Epub 2018 Feb 14.
• Lee SE, Najjengo M, Shaum A, Sekiziyivu AB, Carlock G, Casey RM, Lubega I, Tumwine C, Twinomuhwezi-Oyet E, Nakato WN, Sciarratta CN, Hyde TB, Chu SY, Doshi RH, Kambugu A, Gidudu JF. Adverse events following immunization (AEFI) with fractional one-fifth and one-half doses of yellow fever vaccine compared to standard dose in children 9-23 months old in Uganda, 2019-2022 - final report. Vaccine. 2026 Feb 27;74:128131. doi: 10.1016/j.vaccine.2025.128131. Epub 2026 Jan 8.

Drugs

Indications