<prompt> Which of these is a new oral drug used in treatment of chronic Hepatitis C?Interferon alphaLedipasvirOseltamivirLamivudine  <response>: Ans. b. Ledipasvir Ref: Harrison 19ep2049, I8fe p2556.tLedipasvir is an inhibitor of the hepatitis C virus NS5A protein. Ledipasvir is most commonly used in combination with sofosbuvir for treatment in chronic hepatitis C genotype l patients. Ledipasvir is an inhibitor of the hepatitis C virus NS5A protein. Sofosbuvir, on the other hand, is metabolized to the active uridine analog triphosphate, which acts as a RNA chain terminator when incorporated into the RNA via the NS5B polymerase. LedipasvirLedipasvir is an inhibitor of the hepatitis C virus NS5A proteinQ.The ledipasvirsofosbuvir combination is a direct-acting antiviral agent that interferes with HCV replication and can be used to treat patients with genotypes 1a or 1b without PEG-interferon or ribavirin.On October 10, 2014 the FDA approved the combination product Icdipasvirsofosbuvir called Harvoni.Mechanism of Action:Ledipasvir inhibits an important viral phosphoprotein, NS5A, which is involved in viral replication, assembly secretionClinical Uses:Ledipasvir is most commonly used in combination with sofosbuvir for treatment in chronic hepatitis C genotype1 patientsQ.Side-effects:MC side effects: Fatigue headacheAntiviral Therapy in Hepatitis CIndications for Antiviral Therapy in Hepatitis CDetectable HCV RNA with or without elevated ALTPortalbridging fibrosis or moderate to severe hepatitis on liver biopsyInitial Recommended Treatment depends on the Type of Hepatitis C virusGenotypeRecommended TreatmentHCV genotype 1a 12 weeks of ledipasvir sofosbuvir OR 12 -24 weeks of paritaprevir, ombitasvir, dasabuvir ribavirinHCV genotype 1b 12 weeks of ledipasvir sofosbuvir OR 12 weeks of paritaprevir, ombitasvir dasabuvirHCV genotype 2 12 to 16 weeks of sofosbuvir ribavirinHCV genotype 3 12 weeks of sofosbuvir, ribavirin pegylated interferonHCV genotype 4 12 weeks of ledipasvir sofosbuvir OR paritaprevir, ritonavir, ombitasvir ribavirin, OR 24 weeks of sofosbuvir ribavirinHCV genotype 5 or 6 Sofosbuvir ledipasvir 