The Food and Drug Administration’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) last week voted unanimously that the safety and immunogenicity data on GlaxoSmithKline’s (GSK’s) H5N1 vaccine are adequate to support its licensure for use in adults.
The vaccine contains GSK’s proprietary adjuvant AS03, with the purpose of inducing a stronger immune response with less antigen or active ingredient compared to non-adjuvant influenza vaccines. The vaccine contains 3.75 micrograms (mcg) of antigen, compared with 15 mcg in standard flu vaccines.
The US Department of Health and Human Services (HHS) partially funded GSK’s efforts to develop such an antigen-sparing vaccine for potential use in the U.S. Strategic National Stockpile. Currently, no seasonal flu vaccines used in the United States contain adjuvants, nor does the existing H5N1 vaccine in the US pandemic emergency stockpile. The approval by VRBPAC indicates that the GSK vaccine could become the first adjuvanted flu vaccine to win approval in the United States, CIDRAP reports.
Adjuvant AS03 is used in several other GSK vaccines licensed in other countries. One of these vaccines used in Europe during the 2009 H1N1 flu pandemic was linked with an increased risk of narcolepsy in children in Sweden, Finland and Ireland.
Read more on the VRBPAC’s discussion of the safety profile of the vaccine: FDA panel endorses H5N1 vaccine with adjuvant.