Study to Evaluate the Efficacy and Safety of AMG 301 in Migraine Prevention

A Phase 2a, randomized, double-blind, placebo-controlled, 3-arm parallel group study to
evaluate the efficacy and safety of AMG 301 in subjects with chronic migraine or episodic
migraine.

Inclusion Criteria:

- Adults ≥ 18 to ≤ 60 years of age at the time of signing the informed consent form.

- History of migraine (with or without aura) for ≥ 12 months before screening according
to the International Headache Society (IHS) Classification ICHD-III (Headache
Classification Committee of the International Headache Society, 2013)

- Migraine frequency: ≥ 4 migraine days per month on average across the 3 months before
screening.

- Failed at least 1 medication for prophylactic treatment of migraine due to
tolerability or lack of efficacy

Exclusion Criteria:

- Older than 50 years of age at migraine onset.

- History of cluster headache, hemiplegic migraine headache

- Unable to differentiate migraine from other headaches

- Migraine with continuous pain, in which the subject does not experience any pain-free
periods (of any duration) during the 1 month before the screening period

- History or evidence of any other clinically significant disorder, condition or disease
that, in the opinion of the investigator or Amgen physician, if consulted, would pose
a risk to subject safety or interfere with the study evaluation, procedures or
completion.