transcytosis pathways

Tony,
We discussed earlier the adverse side effects reported by Genentech in relation to the bispecific transferrin receptor antibody.

Back in May 2011, "[Ryan] Watts pointed out that other transcytosis pathways might work better than the transferrin receptor."

Given Ryan Watts comment and the subsequent discovery of adverse side effects using the bispecific antibody, I wondered whether Genentech might be keen to look for alternative pathways to deliver drugs across the BBB? The question arises whether the BEN series utilise the transferrin pathway or have alternative mechanisms of action.

I now understand that the BEN series use a variety of mechanisms of action to cross the BBB none of which include the transferrin receptor. The Genentech interest in evaluating the BEN series may be related, at least in part, to the mechanism of action of the CPPs. Does this mean we avoid the safety pitfalls of the bispecific antibody? I have no idea! In golfing terms we may avoid one bunker only to drive into a different bunker.

Nonetheless, it is interesting and may even be pivotal in explaining Genentech's continued interest in pursuing alternatives to their own engineered antibody which was universally hailed as a breakthrough.

Wayne.