A Study of LY2951742 in Participants With Chronic Cluster Headache

Inclusion Criteria:

- Participants with a history of chronic cluster headache occurring without a remission
period, or with remissions lasting <1 month, for at least 1 year.

- Participants are able to distinguish cluster headache attacks from other headaches.

Exclusion Criteria:

- Current enrollment in or discontinuation within the last 30 days from, a clinical
trial involving any investigational drug or device.

- Current use or any prior exposure to any calcitonin-gene-related peptide (CGRP)
antibody, any antibody to the CGRP receptor, or antibody to nerve growth factor (NGF).

- Are taking indomethacin and/or are suspected of having another distinct trigeminal
autonomic cephalalgia.

- A history of migraine variants that could implicate or could be confused with
ischemia.

- Known hypersensitivity to multiple drugs, monoclonal antibodies or other therapeutic
proteins.

- A history or presence of other medical illness that indicates a medical problem that
would preclude study participation.

- Evidence of significant active or unstable psychiatric disease, in the opinion of the
investigator.

- Women who are pregnant or nursing.