There is a difference between PK/PD, especially aggregate PK/PD, and measuring a biomarker of activity (which was what investorsgold asked about when he compared to anti-IIA activity for Lovenox).
Obviously this might be excusable since plenty of aspects of Lovenox are not fully understood/characterized and yet m-enox was approved. But I think it undebatable that less end-effect characterization will have to suffice for Copaxone.