.it's not clear how well they'll stack up against current migraine therapies, because head-to-head studies haven't been done.....in a news release, the drug's manufacturer, amgen, said the list price will be 5 a month or ,900 annually. costs to patients may vary depending on insurance..u.s..the youngest adult claimant was aged 21, and the eldest aged 79. the age of the youngest children's claim was 8.2 months.