Avid Bioservices Inc (CDMO)

[freethemice]

Betabodies. I don't understand where people are getting the idea that betabodies are the savior.
So far we have seen one poster from this year's AACR meeting.
Phosphatidylserine-Targeting ‘Betabodies’ for the Treatment of Cancer
http://www.peregrineinc.com/images/stories/pdfs/xianming_2013.pdf
They were first mentioned in the 2006 patent, but since then nothing. They should work well considering that
they have a half-life in mouse blood about 5 times longer than 2aG4 (mouse version of bavi). However, the
poster contained no efficacy data in mice, never mind humans. I do expect them to work well, but so far we
just have unfounded expectations as to how well. In addition, their MOA should be no different than bavi.
The betabody is functionally the same as the bavi mab it is just a different construct which removes
the necessity of binding to beta2-glycoprotein I. In that sense it is more like the PGN632 mab which binds
PS directly. The Fc end of the betabody (the "body" part) actually comes from the 2aG4 mab, and in the
human version probably from PGN635. I think they might use an optimized Fc end as shown in this poster from the 2012 AACR meeting.
Increased Fc-FcR Interaction of Human Phosphatidylserine Targeting Antibody Enhances Pro-Inflammatory and ADCC Mechanisms
http://www.peregrineinc.com/images/stories/pdfs/aacr_2012_fc.pdf
I look forward to seeing some survival data from the mouse studies.