What do in vitro studies show about protein-binding interactions between glatiramer acetate (Copaxone) and phenytoin or carbamazepine?

In vitro studies suggest that Copaxone (glatiramer acetate) is highly bound to plasma proteins in blood and neither displaces nor is displaced by phenytoin or carbamazepine, but concomitant use should be monitored carefully because Copaxone could theoretically affect the distribution of protein-bound substances.