Replies to post #4258 on GTC Biotherapeutics (fka GTCB)

[stockdak]

I don't think there is any good information in this regard.

The glycosylation pattern is different in the goats. For Atryn this does not appear to impinge on its function as the EMEA trial demonstrated for the surgery patients.

As to whether or not this will effect the function of ALL the products of goat production system is an unknown. This will have to be evaluated on a case by case basis as it is for every recombinant protein. If one cares to speculate I would say that its an advantage to have some mammalian like glycosylation over cell systems which do not yield any glycosylated protein.

Certainly it has been shown that many entirely non-glycosylated versions of proteins which normally are glycosylated work just find in therapeutic applications. This is not to say that they all have as we only hear about those that do work.

While we are on this line of thought:
Has it been shown by GlycoFi that their glycosylated proteins produced in the modified yeast are identical to their human counterparts?

Do they act identically?
DAK

[DewDiligence]

>Im not barking up wrong the tree, I never once said the Atryn was immunogenic.<

You suggested that GTC’s drug candidates have a greater likelihood of immunogenicity than recombinant drugs produced by other means. There is no evidence I’m aware of to support such a notion.

Further, you ignored the point that GTC can engineer post-translational modifications into its production process should the need arise in a specific instance. This makes the variability of glycosylation close to being a non-issue, IMO, except to the extent that it could have a slight impact on production cost.

If you want a full-fledged match with the glycosylation pattern of an endogenous protein without the need to do post-translational modification, the only way to get it is from plasma. However, plasma-derived drugs have safety concerns that are far more consequential than the issues we’ve been debating, IMO.