Specific polyclonal F(ab')2 neutralize a large panel of highly pathogenic avian influenza A viruses (H5N1) and
Cécile Hélène Herbreteau1, Frédéric Jacquot, Sareth Rith
1Fab'entech, Lyon, France. cecile.herbreteau-delale@fabentech.com.
Aim:
There is still no specific therapy for infection with the highly pathogenic avian influenza A virus (HPAI) H5N1, which caused 39 human cases with a 64% fatality rate in 2013.
Materials & Methods:
We prepared highly purified specific equine polyclonal immunoglobulin fragments (F(ab')2) against H5N1 and tested them for efficacy in vitro and with different administration schedules in H5N1-challenged BALB/c mice.
Results:
in vitro, F(ab')2 neutralized 21 different H5N1 strains from different areas, representative of 11 different clades and sub-clades and 9 years of evolution of the virus. In vivo mouse experiments identified that the most efficient administration protocol consists of five consecutive daily injections after infection; 10 mg/kg giving a 60% increase in survival.
Conclusion:
These data demonstrate the ability of anti-H5N1 F(ab')2 to markedly reduce the mortality and morbidity associated with infection of mice with HPAI H5N1 virus, and their potential for human therapy.
