glycosylated peptide. That’s compared to Stimuvax, which has a 25-amino acid peptide which doesn’t have any sugars on it.
The theory is that if we use this glycosylated antigen, we’ll get an antibody response as well as a T-cell response. We know that Stimuvax primarily produces a T-cell response. What’s not really known is whether producing an antibody response as well would be beneficial from a tumor response perspective. This will be one of the first times that question could be directly answered in the clinic.
X: Can you back up a little and explain the differences between these two vaccines a little more?
BK: Both of these vaccines are constructed in the same way. They take an antigen, which is a peptide, and take an adjuvant—which happens to be different between the two vaccines, and I’ll come back to that. They also take three fats, which are the same. You make a liposome, or a fat globule, that presents the antigen, and the adjuvant, to the immune system. That basic construction between Stimuvax and BGLP40 is the same.
So the antigens are different, as we talked about. But the other difference is in the adjuvant. Stimuvax uses MPL, which is a lipid-A adjuvant from GlaxoSmithKline, and really the old [Seattle-based] Corixa. It’s a biologic adjuvant derived from a bacterial source.
BGLP40 uses a totally synthetic form of the same adjuvant. They are both lipid-A adjuvants. In the case of BGLP40, chemists at what was then Biomira learned how to synthesize it. So it’s made from scratch, as opposed to derived from a biologic source.
X: What’s the advantage of going with a synthetic adjuvant?
BK: Manufacturing control. And we own it.
X: So that means you won’t have to pay royalties to anyone?
