The most common adverse events were nasopharyngitis ( 50 [ 292 % ] of 171 ) , headache ( 12 [ 70 % ] of 171 ) , and malaise ( nine [ 53 % ] of 171 ) in patients receiving ledipasvir-sofosbuvir ; and nasopharyngitis ( 40 [ 235 % ] of 170 ) , anaemia ( 23 [ 135 % ] of 170 ) , and headache in those receiving ledipasvir-sofosbuvir and ribavirin ( 15 [ 88 % ] of 170 ) .