A Study of the Efficacy and Safety of Secukinumab 300 mg in Patients With Thyroid Eye Disease (TED)

This study consisted of the following 3 periods:

1. Screening period (Week -6 to Baseline):

Participants' eligibility was assessed during the Screening period, which occurred for a maximum of 6 weeks. 2. Treatment period (Baseline to Week 16):

Eligible participants were randomized in a 1:1 ratio to one of the following double-blinded treatment arms: * Arm 1: Secukinumab 300 mg s.c. at Baseline, Week 1, 2, 3, 4, 8, 12 * Arm 2: Placebo s.c. at Baseline, Week 1, 2, 3, 4, 8, 12

Participants were stratified according to current smoking status (up to 20% smokers per arm) since smoking has a well-known impact on treatment efficacy in TED. 3. Follow-up/open-label retreatment period (Week 16 up to Week 108):

* Proptosis responders (see definition below) at Week 16 were followed for relapse up to Week 68. If these participants relapsed, they were offered a course of open-label secukinumab at the time of relapse (see "proptosis relapsers" definition below). * Proptosis non-responders (see definition below) at Week 16 were offered the option of open-label secukinumab treatment (with maintenance of blind to initial randomized treatment) for a duration of 16 weeks, i.e., up to Week 32 with last dose at Week 28, as follows:

* Open-label secukinumab 300 mg s.c. at Week 16, 17, 18, 19, 20, 24 and 28. Thereafter (i.e., from Week 32), participants were followed up for a further 24 weeks to assess the relapse rate. * For participants who were proptosis non-responders and who did not receive open-label secukinumab treatment, a follow-up visit 8 weeks after the Week 16 visit needed to be scheduled per protocol. At this follow-up visit, the assessments associated with the Week 24 visit (for responders) were to be performed. * Proptosis relapsers (see definition below) during the follow-up period (from Week 16 onward to Week 68) were offered the option of retreatment with open-label secukinumab for a duration of 16 weeks (with maintenance of blind to initial randomized treatment) at the time of relapse as follows:

* Open-label secukinumab 300 mg s.c. at time of relapse, then at 1, 2, 3, 4, 8 and 12 weeks since time of relapse. Thereafter, participants were followed up for a further 24 weeks (i.e., 40 weeks after start of retreatment) to assess rate of relapse and safety. * For participants not receiving open-label secukinumab treatment a follow-up visit 8 weeks after the Week 16 visit were to be scheduled per protocol, if not yet completed. At this follow-up visit, the assessments associated with the Week 24 visit (for responders) were to be performed.