Efficacy and Safety of Secukinumab in Patients With New Onset of Giant Cell Arteritis Who Are in Clinical Remission

Inclusion Criteria:

Participants eligible for inclusion in this study must meet all of the following criteria:

1. Signed informed consent must be obtained prior to participation in the study.

2. Participant must be able to understand and communicate with the investigator andcomply with the requirements of the study.

3. Male or female participants at least 50 years of age.

4. Diagnosis of new-onset GCA, defined as GCA diagnosed within 6 weeks of baseline (BSL) visit, based on meeting all of the following criteria:

• Age at onset of disease ≥50 years.

• History of Erythrocyte Sedimentation Rate (ESR) ≥30 mm/hr or C-reactive protein (CRP) ≥10 mg/L attributable to active GCA.

• Unequivocal cranial symptoms of GCA (new-onset localized headache, scalp ortemporal artery tenderness, ischemia-related vision loss, or otherwiseunexplained mouth or jaw pain upon mastication) AND/OR symptoms of polymyalgiarheumatica (PMR, defined as shoulder and/or hip girdle pain associated withinflammatory morning stiffness) AND/OR symptoms of limb ischemia (claudication).

• Temporal artery biopsy revealing features of GCA AND/OR evidence of vasculitisin cranial or extracranial arteries by angiography or cross-sectional imagingstudy such as ultrasound, magnetic resonance angiography (MRA), computedtomography angiography (CTA), positron emission tomography - computedtomography (PET-CT)

5. Participants must be in clinical remission at BSL:

• Definition of clinical remission: absence of signs and symptoms attributable toactive GCA as determined by the investigator.

6. Participants with no relapsing GCA at BSL:

• Definition of relapsing GCA: occurrence of clinical relapse after clinicalremission.

7. Prednisolone or equivalent dose (oral) of 20-60 mg/day or equivalent dose of otherglucocorticoids (GCs) at BSL.

Exclusion Criteria:

Participants meeting any of the following criteria are not eligible for inclusion in this study.

3. Participants not eligible for glucocorticoid monotherapy due to known increased riskfor or presence of GC-related adverse-effects or complications and/or intolerance toGCs, such as osteoporosis, diabetes mellitus, cardiovascular disease and glaucoma asassessed at the investigator's discretion (see Appendix 15.2).

4. Previous exposure to secukinumab or another biologic drug directly targeting IL-17or IL-17 receptor.

5. Participants treated with any cell-depleting therapies including but not limited toanti- CD20 or investigational agents (e.g., anti-CD3, anti-CD4, anti-CD5 oranti-CD19).

6. Previous participation in clinical trials for GCA 7. Participants who have beentreated with inhibitors directly targeting IL-12 and/or IL-23 (such as ustekinumab,guselkumab, tildrakizumab, risankizumab), IL-1 or IL-1 receptor (such as anakinra orcanakinumab), or abatacept within 4 weeks or within 5 half-lives of the drug (whichever is longer) prior to BSL.

7. Treatment with tocilizumab, other IL-6/IL6-R inhibitor or JAK inhibitor within 12weeks or within 5 half-lives of the drug (whichever is longer) prior to BSL, or ifparticipant did not respond to or experienced a clinical relapse during treatmentany time before BSL.

8. Any treatment received for GCA other than GCs and participant did not respond totreatment or experienced a clinical relapse during treatment any time before BSL.

9. Any other biologics within 4 weeks or within 5 half-lives of the drug (whichever islonger) prior to BSL.

10. Participants treated with i.v. immunoglobulins or plasmapheresis within 8 weeksprior to BSL.

11. Participants treated with cyclophosphamide, tacrolimus, everolimushydroxychloroquine, cyclosporine A, azathioprine, sulfasalazine, mycophenolatemofetil within 6 months prior to BSL.

12. Participants treated with methotrexate (MTX), within 4 weeks prior to BSL. 14.Participants treated with leflunomide within 8 weeks prior to BSL unless acholestyramine washout has been performed in which case the participant must betreated within 4 weeks of BSL.

13. Participants treated with an alkylating agent within 5 years prior to Baseline,unless specified in other exclusion criteria.

14. Participants requiring systemic chronic glucocorticoid therapy for any other reasonthan GCA at Screening.

15. Receipt of > 100 mg daily intravenous methylprednisolone pulse therapy within 6weeks prior to BSL.

16. Participants requiring chronic (i.e., not occasional "prn") high potency opioidanalgesics for pain management.

17. Participants treated with any investigational agent within 4 weeks or within 5half-lives of the drug (whichever is longer) prior to BSL.

18. Contraindication or hypersensitivity to secukinumab. 21. Active ongoing inflammatorydiseases other than GCA that might confound the evaluation of the benefit ofsecukinumab therapy, including inflammatory bowel disease or uveitis.

19. Active ongoing diseases which in the opinion of the investigator immunocompromisesthe participant and/or places the participant at unacceptable risk for treatmentwith immunomodulatory therapy.

20. Active ongoing inflammatory diseases or underlying metabolic, hematologic, renal,hepatic, pulmonary, neurologic, endocrine, cardiac, infectious or gastrointestinalconditions, which in the opinion of the investigator immunocomprises the participantand/or places the participant at unacceptable risk for participation in animmunomodulatory therapy.

21. Major ischemic event (e.g., myocardial infarction, stroke, etc.) or transientischemic attack (TIA) (except ischemia-related vision loss), related or unrelated toGCA, within 12 weeks of screening.

22. Confirmed diagnosis of any primary form of systemic vasculitis, other than GCA.

23. Active systemic infections during the last 2 weeks (exception: common cold) prior toBSL.

24. History of ongoing, chronic or recurrent infectious disease or evidence oftuberculosis infection as defined by a positive QuantiFERON TB-Plus test.Participants with a positive test may participate in the study if further work up (according to local practice/guidelines) establishes conclusively that theparticipant has no evidence of active tuberculosis. If presence of latenttuberculosis is established, then treatment according to local country guidelinesmust be initiated prior to BSL.

25. Live vaccinations within 6 weeks prior to BSL or planned live vaccination duringstudy participation until 12 weeks after last study treatment administration.