A Study to Evaluate the Efficacy, Safety, Pharmacokinetics, and Pharmacodynamics of Satralizumab in Participants With Thyroid Eye Disease

Primary Outcome Measures

1. Percentage of Participants in the Active TED Population Who Achieved ≥ 2 Millimeters (mm) Reduction in Proptosis From Baseline at Week 24 in the Study Eye
   Percentage of participants in the active TED population (i.e., participants who have active disease) who achieved a ≥ 2 mm reduction in proptosis from baseline (Day 1) to Week 24 in the study eye, with no corresponding deterioration of proptosis (≥ 2 mm increase) in the fellow eye have been reported. Percentages have been rounded off.

Secondary Outcome Measures

1. Percentage of Participants in the Overall Population Who Achieved ≥ 2 mm Reduction in Proptosis From Baseline at Week 24 in the Study Eye
   Percentage of participants in the overall population (i.e., participants with active and chronic inactive TED) who achieved a ≥ 2 mm reduction in proptosis from baseline (Day 1) to Week 24 in the study eye, with no corresponding deterioration of proptosis (≥ 2 mm increase) in the fellow eye have been reported. Percentages have been rounded off.
2. Change From Baseline in Proptosis at Week 24 in Active TED Population for Study Eye
   This analysis used a Mixed-effects Model for Repeated Measure (MMRM) model. Adjusted mean values have been reported here.
3. Change From Baseline in Proptosis at Week 24 in Overall Population for Study Eye
   This analysis used a MMRM model. Adjusted mean values have been reported here.
4. Percentage of Participants in Active TED Population Achieving ≥ 1 Grade Reduction/Improvement in Diplopia at Week 24
   Diplopia grade was assessed with the use of the Gorman subjective diplopia score (range: 0-3 points), which included: no diplopia (absent, scored as 0), diplopia in the primary position of gaze when the participant is tired or awakening (intermittent, scored as 1), diplopia at extremes of gaze (inconstant, scored as 2), and continuous diplopia in the primary or reading position (constant, scored as 3). Participants with active TED with diplopia present at baseline who had Grade ≥1 reduction or improvement at Week 24 have been reported. Percentages have been rounded off.
5. Percentage of Participants in the Overall Population Achieving ≥ 1 Grade Reduction/Improvement in Diplopia at Week 24
   Diplopia grade was assessed with the use of the Gorman subjective diplopia score (range: 0-3 points), which included: no diplopia (absent, scored as 0), diplopia in the primary position of gaze when the participant is tired or awakening (intermittent, scored as 1), diplopia at extremes of gaze (inconstant, scored as 2), and continuous diplopia in the primary or reading position (constant, scored as 3). Participants with active and chronic inactive TED with diplopia present at baseline who had Grade ≥1 reduction or improvement at Week 24 have been reported. Percentages have been rounded off.
6. Percentage of Participants in Active TED Population Achieving Absence of Motility-induced Pain at Week 24
   Percentages have been rounded off.
7. Percentage of Participants in Active TED Population Achieving Absence of Spontaneous Pain at Week 24
   Percentages have been rounded off.
8. Percentage of Participants in Active TED Population With a ≥ 6-point Improvement in the Visual Functioning Subscale of the Graves' Ophthalmopathy Quality-of-life (GO-QoL) From Baseline at Week 24
   The GO-QoL is a 16-item self-administered questionnaire divided into two sub-scales, and is used to assess the perceived effects of TED by the participants on their: 1) Visual Functioning (questions 1-8); and 2) Appearance (questions 9-16). Both subscales and overall score (sum of scores from all 16 questions) are transformed to a scale of 0 to 100. Higher total scores indicate better QoL. Percentages have been rounded off.
9. Percentage of Participants in Active TED Population With a ≥ 6-point Improvement in the Appearance Subscale of the GO-QoL From Baseline at Week 24
   The GO-QoL is a 16-item self-administered questionnaire divided into two sub-scales and used to assess the perceived effects of TED by the participants on their: 1) Visual Functioning (questions 1-8); and 2) Appearance (questions 9-16). Both subscales and overall score (sum of scores from all 16 questions) are transformed to a scale of 0 to 100. Higher total scores indicate better QoL. Percentages have been rounded off.
10. Percentage of Participants in Active TED Population Who Achieved Overall Response in the Study Eye at Week 24
    Overall Response was defined as a ≥ 2-point reduction in clinical activity score (CAS), and a ≥ 2 mm reduction in proptosis from baseline in the study eye, provided there is no corresponding deterioration in CAS or proptosis (≥ 2-point/mm increase) in the fellow eye. The CAS is a 7-item description of clinical activity, including: 1. Spontaneous orbital pain; 2. Gaze evoked orbital pain; 3. Eyelid swelling that is considered to be due to TED; 4. Eyelid erythema; 5. Conjunctival redness that is considered to be due to active TED (ignore "equivocal" redness); 6. Chemosis; 7. Swelling of caruncle or plica. Each item is scored as 1 (present) or 0 (absent) and scores for each item are summed for total score of 0 (no inflammatory symptoms) to 7 (most inflammatory symptoms). Higher scores indicate worse symptoms. Percentages have been rounded off.
11. Percentage of Participants in Active TED Population Who Achieved a ≥ 2-point Reduction in CAS in the Study Eye From Baseline to Week 24
    CAS is a 7-item description of clinical activity, including: 1. Spontaneous orbital pain; 2. Gaze evoked orbital pain; 3. Eyelid swelling that is considered to be due to TED; 4. Eyelid erythema; 5. Conjunctival redness that is considered to be due to active TED (ignore "equivocal" redness); 6. Chemosis; 7. Swelling of caruncle or plica. Each item is scored as 1 (present) or 0 (absent) and scores for each item are summed for total score of 0 (no inflammatory symptoms) to 7 (most inflammatory symptoms). Higher scores indicate worse symptoms. Percentages have been rounded off.
12. Percentage of Participants in Active TED Population Who Achieved a CAS Value of 0 or 1 in the Study Eye at Week 24
    CAS is a 7-item description of clinical activity, including: 1. Spontaneous orbital pain; 2. Gaze evoked orbital pain; 3. Eyelid swelling that is considered to be due to TED; 4. Eyelid erythema; 5. Conjunctival redness that is considered to be due to active TED (ignore "equivocal" redness); 6. Chemosis; 7. Swelling of caruncle or plica. Each item is scored as 1 (present) or 0 (absent) and scores for each item are summed for total score of 0 (no inflammatory symptoms) to 7 (most inflammatory symptoms). Higher scores indicate worse symptoms. Percentages have been rounded off.
13. Percentage of Participants With a ≥ 10-point Improvement in the Ocular Surface Disease Index (OSDI) Overall Scores Across All Levels of Baseline Severity at Week 24 in Overall Population
    The OSDI instrument is a validated dry eye questionnaire and consists of three main sections concerning ocular symptoms, visual function, and environmental factors. It comprises of 12 questions and for every question, participants select a number between 0 and 4, where 0 equals "none of the time" and 4 equals "all of the time" with totals of score ranging from 0 to 100. Higher scores represent a worse disease index. Percentages have been rounded off.
14. Change From Baseline in the OSDI Ocular Symptoms, and Vision-related Function Subscale Scores at Week 24 in the Overall Population
    The OSDI instrument is a validated dry eye questionnaire and consists of three main sections concerning ocular symptoms, visual function, and environmental factors. It comprises of 12 questions and for every question, participants select a number between 0 and 4, where 0 equals "none of the time" and 4 equals "all of the time" with totals of score ranging from 0 to 100. Higher scores represent a worse disease index. This analysis used a MMRM model. Adjusted mean values have been reported here.
15. Change From Baseline in Oxford Corneal Staining Scores at Week 24 in the Overall Population
    Corneal staining was graded using Oxford Corneal Staining Chart which consists of a 6-point scale. Staining assessment will be based on the intensity of fluorescein staining, ranging from Grade 0 to V for each panel (0=absent; I=minimal; II=mild; III=moderate; IV= marked; and V=severe). Higher grade indicates worse disease index. The observer compares the overall appearance of the participant's corneal staining with the reference figure in the protocol. The observer selects the appropriate grade that best represents the state of corneal staining. The staining score were recorded for the exposed interpalpebral cornea and conjunctiva. This analysis used a MMRM model. Adjusted mean values have been reported here.
16. Percentage of Participants Who Achieved Complete Binocular Diplopia Response at Week 24 in Overall Population
    The percentage of participants achieving a complete binocular diplopia response (diplopia score=0) at Week 24 have been reported. Diplopia grade was assessed with the use of the Gorman subjective diplopia score (range: 0-3 points), which included: no diplopia (absent, scored as 0), diplopia in the primary position of gaze when the participant is tired or awakening (intermittent, scored as 1), diplopia at extremes of gaze (inconstant, scored as 2), and continuous diplopia in the primary or reading position (constant, scored as 3). Percentages have been rounded off.
17. Percentage of Participants (Proptosis Non-responders at Week 24) Achieving ≥ 2 mm Reduction in Proptosis at Week 48 in the Study Eye
    Percentage of participants (proptosis non-responders) who will achieve a ≥ 2 mm reduction in proptosis from baseline (Day 1) to Week 48 in the study eye, with no corresponding deterioration of proptosis (≥ 2 mm increase) in the fellow eye will be reported.
18. Percentage of Participants (Proptosis Non-responders at Week 24) Achieving Overall Response at Week 48
    Overall Response is defined as a ≥ 2-point reduction in CAS, and a ≥ 2 mm reduction in proptosis from baseline in the study eye, provided there is no corresponding deterioration in CAS or proptosis ( ≥ 2-point/mm increase) in the fellow eye. The CAS is a 7-item description of clinical activity, including: 1. Spontaneous orbital pain; 2. Gaze evoked orbital pain; 3. Eyelid swelling that is considered to be due to TED; 4. Eyelid erythema; 5. Conjunctival redness that is considered to be due to active TED (ignore "equivocal" redness); 6. Chemosis; 7. Swelling of caruncle or plica. Each item is scored as 1 (present) or 0 (absent) and scores for each item are summed for total score of 0 (no inflammatory symptoms) to 7 (most inflammatory symptoms). Higher scores indicate worse symptoms.
19. Percentage of Participants (Proptosis Non-responders at Week 24) Achieving a ≥ 2-point Reduction in CAS in the Study Eye From Baseline to Week 48
    The CAS is a 7-item description of clinical activity, including: 1. Spontaneous orbital pain; 2. Gaze evoked orbital pain; 3. Eyelid swelling that is considered to be due to TED; 4. Eyelid erythema; 5. Conjunctival redness that is considered to be due to active TED (ignore "equivocal" redness); 6. Chemosis; 7. Swelling of caruncle or plica. Each item is scored as 1 (present) or 0 (absent) and scores for each item are summed for total score of 0 (no inflammatory symptoms) to 7 (most inflammatory symptoms). Higher scores indicate worse symptoms.
20. Percentage of Participants (Proptosis Non-responders at Week 24) Achieving Grade ≥ 1 Reduction/Improvement in Diplopia at Week 48 in Participants With Baseline Diplopia > 0
    Diplopia grade was assessed with the use of the Gorman subjective diplopia score (range: 0-3 points), which included: no diplopia (absent, scored as 0), diplopia in the primary position of gaze when the participant is tired or awakening (intermittent, scored as 1), diplopia at extremes of gaze (inconstant, scored as 2), and continuous diplopia in the primary or reading position (constant, scored as 3).
21. Percentage of Participants (Proptosis Non-responders at Week 24) With a ≥ 6-point Improvement in the Visual Functioning and Appearance Subscale Scores of the GO-QoL From Week 24 to Week 48
    The GO-QoL is a 16-item self-administered questionnaire divided into two sub-scales and used to assess the perceived effects of TED by the participants on their: 1) Visual Functioning (questions 1-8); and 2) Appearance (questions 9-16). Both subscales and overall score (sum of scores from all 16 questions) are transformed to a scale of 0 to 100. Higher total scores indicate better QoL.
22. Percentage of Participants (Proptosis Non-responders at Week 24) With a ≥ 6-point Improvement in the Visual Functioning and Appearance Subscale Scores of the GO-QoL From Baseline to Week 48
    The GO-QoL is a 16-item self-administered questionnaire divided into two sub-scales and used to assess the perceived effects of TED by the participants on their: 1) Visual Functioning (questions 1-8); and 2) Appearance (questions 9-16). Both subscales and overall score (sum of scores from all 16 questions) are transformed to a scale of 0 to 100. Higher total scores indicate better QoL.
23. Change From Baseline in Proptosis at Week 48 (in Proptosis Non-responders at Week 24)
    Proptosis response is defined as achieving a ≥ 2 mm reduction in proptosis from baseline (Day 1) to Week 24 in the study eye, with no corresponding deterioration of proptosis (≥ 2 mm increase) in the fellow eye.
24. Percentage of Participants (Proptosis Non-responders at Week 24) Requiring Surgical Intervention for TED up to Week 48
25. Percentage of Participants (Proptosis Responders at Week 24) With Worsening of Proptosis by ≥ 2 mm From Week 24 to Week 48
26. Percentage of Participants (Proptosis Responders at Week 24) With Worsening of Proptosis by ≥ 2 mm From Baseline to Week 48
27. Percentage of Participants (Proptosis Responders at Week 24) With Maintenance of Proptosis Response From Week 24 at Week 48
    Proptosis response is defined as achieving a ≥ 2 mm reduction in proptosis from baseline (Day 1) to Week 24 in the study eye, with no corresponding deterioration of proptosis (≥ 2 mm increase) in the fellow eye.
28. Percentage of Participants (Proptosis Responders at Week 24) With Maintenance of CAS Response From Week 24 at Week 48
    The CAS is a 7-item description of clinical activity, including: 1. Spontaneous orbital pain; 2. Gaze evoked orbital pain; 3. Eyelid swelling that is considered to be due to TED; 4. Eyelid erythema; 5. Conjunctival redness that is considered to be due to active TED (ignore "equivocal" redness); 6. Chemosis; 7. Swelling of caruncle or plica. Each item is scored as 1 (present) or 0 (absent) and scores for each item are summed for total score of 0 (no inflammatory symptoms) to 7 (most inflammatory symptoms). Higher scores indicate worse symptoms.
29. Percentage of Participants (Proptosis Responders at Week 24) With Maintenance of Proptosis Response From Baseline at Week 48
    Proptosis response is defined as achieving a ≥ 2 mm reduction in proptosis from baseline (Day 1) to Week 24 in the study eye, with no corresponding deterioration of proptosis (≥ 2 mm increase) in the fellow eye.
30. Percentage of Participants (Proptosis Responders at Week 24) With Maintenance of CAS Response From Baseline at Week 48
    The CAS is a 7-item description of clinical activity, including: 1. Spontaneous orbital pain; 2. Gaze evoked orbital pain; 3. Eyelid swelling that is considered to be due to TED; 4. Eyelid erythema; 5. Conjunctival redness that is considered to be due to active TED (ignore "equivocal" redness); 6. Chemosis; 7. Swelling of caruncle or plica. Each item is scored as 1 (present) or 0 (absent) and scores for each item are summed for total score of 0 (no inflammatory symptoms) to 7 (most inflammatory symptoms). Higher scores indicate worse symptoms.
31. Change in Proptosis From Week 24 to 48 (in Proptosis Responders at Week 24)
    Proptosis response is defined as achieving a ≥ 2 mm reduction in proptosis from baseline (Day 1) to Week 24 in the study eye, with no corresponding deterioration of proptosis (≥ 2 mm increase) in the fellow eye.
32. Change in CAS From Week 24 to 48 (in Proptosis Responders at Week 24)
    The CAS is a 7-item description of clinical activity, including: 1. Spontaneous orbital pain; 2. Gaze evoked orbital pain; 3. Eyelid swelling that is considered to be due to TED; 4. Eyelid erythema; 5. Conjunctival redness that is considered to be due to active TED (ignore "equivocal" redness); 6. Chemosis; 7. Swelling of caruncle or plica. Each item is scored as 1 (present) or 0 (absent) and scores for each item are summed for total score of 0 (no inflammatory symptoms) to 7 (most inflammatory symptoms). Higher scores indicate worse symptoms.
33. Percentage of Participants (Proptosis Responders at Week 24) With a ≥ 6-point Improvement in the Visual Functioning and Appearance Subscale Scores of the GO-QoL From Week 24 to Week 48
    The GO-QoL is a 16-item self-administered questionnaire divided into two sub-scales and used to assess the perceived effects of TED by the participants on their: 1) Visual Functioning (questions 1-8); and 2) Appearance (questions 9-16). Both subscales and overall score (sum of scores from all 16 questions) are transformed to a scale of 0 to 100. Higher total scores indicate better QoL.
34. Percentage of Participants (Proptosis Responders at Week 24) With a ≥ 6-point Improvement in the Visual Functioning and Appearance Subscale Scores of the GO-QoL From Baseline to Week 48
    The GO-QoL is a 16-item self-administered questionnaire divided into two sub-scales and used to assess the perceived effects of TED by the participants on their: 1) Visual Functioning (questions 1-8); and 2) Appearance (questions 9-16). Both subscales and overall score (sum of scores from all 16 questions) are transformed to a scale of 0 to 100. Higher total scores indicate better QoL.
35. Change From Baseline in Proptosis to Week 48 (in Proptosis Responders at Week 24)
    Proptosis response is defined as achieving a ≥ 2 mm reduction in proptosis from baseline (Day 1) to Week 24 in the study eye, with no corresponding deterioration of proptosis (≥ 2 mm increase) in the fellow eye.
36. Change From Baseline in CAS to Week 48 (in Proptosis Responders at Week 24)
    The CAS is a 7-item description of clinical activity, including: 1. Spontaneous orbital pain; 2. Gaze evoked orbital pain; 3. Eyelid swelling that is considered to be due to TED; 4. Eyelid erythema; 5. Conjunctival redness that is considered to be due to active TED (ignore "equivocal" redness); 6. Chemosis; 7. Swelling of caruncle or plica. Each item is scored as 1 (present) or 0 (absent) and scores for each item are summed for total score of 0 (no inflammatory symptoms) to 7 (most inflammatory symptoms). Higher scores indicate worse symptoms.
37. Percentage of Participants (Proptosis Responders at Week 24) Requiring Surgical Intervention for TED up to Week 48
38. Number of Participants With Adverse Events (AEs)
    An AE is any untoward medical occurrence in a clinical study participant temporally associated with the use of a study treatment, whether or not considered related to the study treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of study intervention.
39. Serum Trough Concentration (Ctrough) of Satralizumab at Specified Timepoints
40. Number of Participants With Anti-drug Antibodies (ADAs) to Satralizumab at Baseline and During the Study
    Participants will be considered to be ADA positive if they were ADA negative at baseline but developed an ADA response following study drug exposure (treatment-induced ADA response), or if they were ADA positive at baseline and the titer of one or more post-baseline samples is at least 4-fold greater than the titer of the baseline sample (treatment-enhanced ADA response).