4208 may be better than RDEA594 for patients on concomitant medication. See 5.6.3. http://www.ocresearch.com/wp-content/uploads/2012/05/Ardea-RDEA594-301-Protocol-1-of-2.pdf Patients on 4208 on the other hand don't need to have adjustments made to medication. See slide 19. http://www.biocryst.com/PDFs/BCX4208-20324weekresultsIRfinal9Jan12.pdf