- Therapies that must be discontinued or substituted prior to study visit Day 1, or must be temporarily interrupted during the course of the study, include the following: a) Medications known to lower the seizure threshold within 4 weeks before Study Day 15 (Cycle 1 Day 1) and b) Medications known to induce or inhibit drug metabolizing enzymes (CYP3A4, CYP2C9, CYP2C19 and CYP2C8) or transporter proteins (P-gp, BRCP, OATP1B1, and OATPB3)