This study used a single-cohort, 3-treatment arm, randomized, double-blind study design in adult patients with episodic migraine. The subjects were randomized to receive either erenumab or placebo in a 2:3:3 ratio (erenumab 140 mg: erenumab 70 mg: placebo). A screening period of 2 weeks was used to assess initial eligibility, followed by a 4-week baseline period. After randomization/Day 1, visits occurred at four week intervals until Week 12, which was the End of Treatment. The final visit, Last Patient Last Visit was a Safety Follow-Up visit, which occurred 12 weeks later, at Week 24.
