This is a 128-week open-label study to assess the long-term safety and tolerabilty of the monoclonal antibody erenumab in migraine patients.

This was an open-label, multi-center, single arm study with flexible dosing allowing both dose adjustment and one drug holiday per patient.

The study design consisted of 3 parts:

• Screening Epoch (0 - 2 weeks): required for all patients to assess initial eligibility. Eligible patients came from study CAMG334ADE01 (NCT03828539).
• Open-label Treatment Epoch (128 weeks): Individual patients were treated for 128 weeks. In this open-label treatment phase, the erenumab dose could be adjusted from 70 mg to 140 mg or vice versa at the discretion of the physician at any scheduled study visit. Additionally, a voluntary single treatment interruption ('drug holiday') of up to 24 weeks (approximately six months) could be introduced after at least 12 weeks of treatment in the open-label Treatment Epoch.
• Follow-up Epoch (4 weeks): A Follow-Up Visit 4 weeks after the last regular study visit (8 weeks after last investigational medicinal product [IMP] application) was required as part of routine safety monitoring.

The study population consisted of patients with a documented history of episodic (4 - 14 baseline migraine days) or chronic migraine (≥15 baseline headache days), who had been successfully randomized to clinical trial CAMG334ADE01.

Key inclusion Criteria:

• Signed informed consent must be obtained prior to participation in the study
• Patient is capable of understanding the nature, significance and implications of the clinical trial.
• Adults ≥18 years of age upon entry into screening

Key exclusion Criteria:

• Use of a prophylactic migraine medication within five plasma clearance half-lives, or a device or procedure within one month prior to the start of the Open-label Treatment Epoch. This exclusion criteria does not apply to erenumab or topiramate administered within clinical trial CAMG334ADE01
• Any prior exposure to (investigational) prophylactic migraine products targeting the CGRP pathway, other than erenumab.

Novartis is committed to sharing with qualified external researchers, access to patient-level data and supporting clinical documents from eligible studies. These requests are reviewed and approved by an independent review panel on the basis of scientific merit. All data provided is anonymized to respect the privacy of patients who have participated in the trial in line with applicable laws and regulations.

This trial data availability is according to the criteria and process described on www.clinicalstudydatarequest.com