• History of migraine (with or without aura) for ≥ 6 months before Screening.

• History of 1 to 8 moderate or severe attacks per month during the 2 months prior to screening.

• 1 or more migraine days requiring treatment during the Observation Phase.

• Prophylactic migraine medication is permitted if the dose has been stable for at least 12 weeks prior to the Screening Visit.

• Ability to distinguish between migraine and other types of headaches.

• Weight \> 15 kg. For EU countries only: Participants 12 to \< 18 years of age must have a body weight of \>25kg.

• Adequate venous access for blood sampling.

• Male and female participants 6 to \< 18 years of age (participants must not reach their 18th birthday on or before the Baseline visit).