In Vitro Characterization and In Vivo Effectiveness of Ebola Virus Specific Equine Polyclonal F(ab')2.

There is no vaccine or approved therapy against lethal Ebola virus (EBOV). We investigated a proven technology platform to produce polyclonal IgG fragments, F(ab')2, against EBOV. Horses immunized with nanoparticles harboring surface glycoprotein trimers of EBOV-Zaire/Makona produced anti-Ebola IgG polyclonal antibodies with high neutralization activity. Highly purified equine anti-Ebola F(ab')2 showed strong cross-neutralization of 2 Zaire EBOV strains (Gabon 2001 and Makona) and in vivo 3 or 5 daily F(ab')2 intraperitoneal injections provided 100% protection to BALB/c mice against lethal EBOV challenge. Rapid preparation of purified equine anti-Ebola F(ab')2 offers a potentially efficient therapeutic approach against EBOV disease in humans.

Efficacy of a specific polyclonal equine F(ab')2 against avian influenza (H5N1) in ferrets: synergy with oseltamivir.

AIM: Current therapies against avian influenza (H5N1) provide limited clinical benefit. FBF-001 is a highly purified equine polyclonal immunoglobulin fragment against H5N1. METHODS: Using a ferret model of severe acute H5N1 infection, we assessed FBF-001 when administered on the same day or 1 day after viral challenge, in comparison with oseltamivir therapy. RESULTS: Untreated animals died 2-3 days after challenge. FBF-001 prevented most severe illness and reduced nasal viral load, with best efficacy when administered on the day of viral challenge. Oseltamivir and FBF-001 had synergistic impact on survival. CONCLUSION: FBF-001 prevented severe consequences of lethal H5N1 challenge in ferrets by controlling viral replication, an effect synergistic to oseltamivir. FBF-001 has recently been granted EMA orphan drug status.