NIAID announces phase 1 trial of yellow fever vaccine

The National Institute of Allergy and Infectious Diseases has begun an early-stage, phase 1 clinical trial of an investigational vaccine for the prevention of yellow fever virus.

In 2013, yellow fever virus caused an estimated 84,000 to 170,000 cases of severe disease and 29,000 to 60,000 deaths, according to WHO.

“Yellow fever has recently re-emerged as a major public health threat in parts of Africa. Although a vaccine exists to prevent this serious disease, it is currently in short supply, and it is not recommended for certain populations, such as pregnant women and people older than 60 years,” Anthony S. Fauci, MD, director of NIAID, said in a press release, “We must develop new options for preventing this terrible disease.”

Since 2006, over 105 million people in Africa have received yellow fever vaccinations, according to WHO. However, supplies are limited, and in some cases the vaccine has caused severe adverse reactions.

The NIAID’s placebo-controlled, double blind study will include 90 healthy men and women aged 18 to 45 years who have never been infected with a flavivirus such as yellow fever. Researchers will place participants into 6 groups — one group will receive the current yellow fever vaccine subcutaneously and five will receive the investigational MVA-BN-YF vaccine, developed by Bavarian Nordic, intramuscularly. Researchers will administer both vaccines either with or without ISA 720, an experimental adjuvant shown in previous clinical trials to induce an immune response after one dose of vaccine. Participants will receive one or two doses of vaccine or placebo 1 month apart.

Anthony S. Fauci

According to the press release, the MVA-BN-YF vaccine is based on Bavarian Nordic’s proprietary MVA-BN platform that uses an attenuated version of the Modified Vaccinia Ankara (MVA) virus as a vector. MVA-BN–based vaccines have been successfully used in over 7,600 people — 1,000 of whom were immunocompromised.

One goal of the trial is to determine whether two doses of unadjuvanted vaccine or a single dose of ISA 720 adjuvanted vaccine could provide protection against yellow fever, according to the press release.

NIAID-funded Vaccine and Treatment Evaluation Units will conduct the multi-site trial at the University of Iowa in Iowa City and Saint Louis University in Missouri, and Emory Vaccine Center in Decatur, Georgia will help with data evaluation.