- Individuals who are taking the following medications and require continuation of the medications during the proposed study period will be excluded, given known interactions with ledipasvir-sofosbuvir: Carbamazepine, phenytoin, phenobarbital, oxcarbazepine, rifabutin, rifampin, isoniazid, rifapentine, rosuvastatin, proton pump inhibitors, digoxin, modafinil, and St. John's wort, milk thistle, Echinacea.