Overview Estetrol (E4)/Drospirenone (DRSP) Drug-drug Interaction (DDI) Study Status: Completed Trial end date: 2018-10-08 Target enrollment: Participant gender: Summary The present study is designed to determine the effect of valproic acid (VAL), a UGT2B7 inhibiting drug, on the pharmacokinetics (PK) of estetrol (E4) Phase: Phase 1 Details Lead Sponsor: EstetraCollaborator: Quotient SciencesTreatments: DrospirenoneValproic Acid