VACCINE

Expert Review Of Vaccines • June 2015
The avian influenza vaccine Emerflu
Why did it fail?
Author information
Young BE1, Sadarangani SP, Leo YS.
Communicable Diseases Centre
Institute of Infectious Diseases and Epidemiology
Communicable Diseases Centre,
144 Moulmein Road, Singapore
Abstract
Emerflu is an inactivated, split-virion pandemic preparedness
vaccine, containing 30 μg of hemagglutinin (HA)
and 600 μg of aluminum hydroxide adjuvant. It is administered
in two doses, 3 weeks apart. Only moderate immunogenicity
was evident from clinical studies with the
vaccine in adults, and HA antibody responses were below
the criteria established by the EMA and US FDA for licensure.
With the exception of Australia, the vaccine remains
unlicensed. Further clinical development appears to have
been suspended, and newer adjuvants such as MF59 and
AS03 have since demonstrated safety and superior immunogenicity
with lower HA doses. Emerflu is symbolic
of the failure of aluminum salts as an adjuvant for influenza
vaccines. Reasons for this failure are unclear, and
may reflect problems with the adjuvant-antigen complex
or interference in the immune response by heterosubtypic
immunity.
“Emerflu is symbolic
of the failure of aluminum salts
as an adjuvant for
influenza vaccines.”
http://www.ncbi.nlm.nih.gov/pubmed/26098721