H1N1 COUNTERMEASURES STRATEGY AND ... - PHE Home

NBSB Pandemic Influenza Working Group
Detailed Report
Polyclonal:
Generated more rapidly
o IVIG vs. plasma
Less development expense
Higher sustained manufacturing expense
Heterogeneity/less potent
o Advantage for resistance?
o Most IgG not specific
Large dose/volume
May be easier to approve
o Intrinsic targets unlikely
Monoclonal:
Slower to develop
o More technically difficult
Higher development expense
Lower sustained manufacturing expense
Homogeneity/more potent
o More consistent
o Select neutralizing monoclonal antibody only
Small dose/volume
More difficult to approve
o Treated as novel compounds
The timeline for developing monoclonal antibodies can reach 3–4 years. Dr. Beigel
noted recent studies suggesting antibody isolation may be decreased from 6–12 months to
28 days, though this study was specifically looking at vaccines and not convalescent
subjects. He said the time for monoclonal antibody engineering could be reduced from
the current 6–12 months. Investigators are working to reduce the time to develop master
cell lines from 12 months to 6 months. The time for manufacturing and release would
stay the same. So while the timeline can be improved, it is still unlikely that monoclonal
antibodies could be developed rapidly enough (with current technologies and approval
processes) for emerging infectious diseases.
The NIH is developing a protocol for H1N1 to collect plasma from convalescent subjects
and vaccines. The protocol is still in draft form and needs IRB and FDA approval.
Discussions are underway with a manufacturer for IVIG. Depending on the course of the
H1N1 epidemic, the protocol may use source plasma or IVIG.
Dr. Beigel concluded that passive antibody is an option for emerging infectious diseases,
but it is labor-intensive. Plasma collection and IVIG development is not as rapid as
assumed, but it’s still faster than de novo drug development. In the best-case-scenario,
plasma could be available in 3 months, and IVIG in 7–12 months. Monoclonal
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