To Assess the Patients' Ability to Self-Administer Fasinumab

The primary objective is to demonstrate that the auto-injector(AI) is suitable to be used to administer fasinumab at home by patients or their caregivers, as measured by collecting 12 weeks of actual-use data on the technical performance of the device. The secondary objectives of the study are: * To evaluate the successful injection of fasinumab by patients or their caregivers using the AI in an unsupervised setting * To evaluate patient/caregiver satisfaction with the AI for fasinumab injection in an unsupervised setting * To evaluate exposure in serum for fasinumab administered by patients or their caregivers using an AI in an unsupervised setting, or fasinumab administered by study staff using a PFS that has been used in the phase 3 program * To characterize the safety, tolerability, and immunogenicity of fasinumab administered by patients or their caregivers using an AI in an unsupervised setting, or fasinumab administered by study staff using a PFS that has been used in the phase 3 program