• Diagnosis of Giant cell arteritis (GCA) according to the revised American College of Rheumatology criteria

• GCA diagnosis confirmed by either temporal artery biopsy revealing features of GCA either at time of diagnosis or at other timepoint during disease history; or evidence of cranial GCA either at time of diagnosis or at other timepoint during disease history by cranial doppler-ultrasound; or cranial Magnetic Resonance Imaging (MRI) or Magnetic Resonance Angiography; or other imaging modality upon agreement with the sponsor or evidence of GCA by angiography or cross-sectional imaging (ultrasound, MRI, computed tomography \[CT\], positron emission tomography \[PET\])

• Have new onset or relapsing GCA

• Have active GCA within 6 weeks of first study intervention: Active GCA: presence of signs and symptoms of GCA and elevated erythrocyte sedimentation rate (ESR) greater than or equal to (\>=) 30 millimeter per hour (mm/hour), or C-reactive protein (CRP) \>= 10 milligrams per liter (mg/L) (or 1 milligrams per deciliter \[mg/dL\]), attributed to active GCA. ESR \>= 30 mm/hour or CRP \>= 10 mg/L (or 1 mg/dL) is not required if active GCA has been confirmed by a positive temporal artery biopsy or ultrasound or other imaging modality within 6 weeks of first study intervention

• Clinically stable GCA disease on a glucocorticoid (GC) dose between 20 and 60 milligrams per day (mg/day) (prednisone or equivalent) at randomization such that the participant is able to safely participate in the protocol defined prednisone taper regimen, in the opinion of the investigator