[Goose]

So the effectiveness of CP also depends on the selection of donors (when they recovered and titres of Ab, etc).  Not saying this is the reason why they shouldn't have started the randomized clinical trial earlier, but it's something that can have an impact on a study.

As you probably already know, these characteristics also make it more difficult to build a therapy around CP. You don't know exactly what you have in the bag and the next bag may be real different. This is also a big reason monoclonal antibodies will be preferred when a "good" mix is determined. You get the same antibody concentrations each time so at least the dose delivered is precisely known. Unfortunately that is going to take some time, so CP needs to be evaluated, despite the difficulties. If monoclonals make it obsolete very quickly, so much the better.

[Goose]

So the effectiveness of CP also depends on the selection of donors (when they recovered and titres of Ab, etc).  Not saying this is the reason why they shouldn't have started the randomized clinical trial earlier, but it's something that can have an impact on a study.

As you probably already know, these characteristics also make it more difficult to build a therapy around CP. You don't know exactly what you have in the bag and the next bag may be real different. This is also a big reason monoclonal antibodies will be preferred when a "good" mix is determined. You get the same antibody concentrations each time so at least the dose delivered is precisely known. Unfortunately that is going to take some time, so CP needs to be evaluated, despite the difficulties. If monoclonals make it obsolete very quickly, so much the better.