| E.1 Medical condition or disease under investigation | 
| E.1.1 | Medical condition(s) being investigated |  | 
| E.1.1.1 | Medical condition in easily understood language |  | 
| E.1.1.2 | Therapeutic area | Diseases [C] - Immune System Diseases [C20] | 
| MedDRA Classification | 
| E.1.2 Medical condition or disease under investigation | 
| 
| E.1.2 | Version | 19.0 |  
| E.1.2 | Level | PT |  
| E.1.2 | Classification code | 10071400 |  
| E.1.2 | Term | Axial spondyloarthritis |  
| E.1.2 | System Organ Class | 10028395 - Musculoskeletal and connective tissue disorders |  | 
| E.1.3 | Condition being studied is a rare disease | No | 
| E.2 Objective of the trial | 
| E.2.1 | Main objective of the trial | 
| Percentage of Participants Achieving an Assessment of SpondyloArthritis International Society (ASAS) 40 Response at Week 24 |  | 
| E.2.2 | Secondary objectives of the trial | 
| -Percentage of Participants Achieving an ASAS 20 Response at Week 24 -Percentage of Participants who Achieve at Least 50% Improvement From Baseline in Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) at Week 24
 -Change From Baseline in Bath Ankylosing Spondylitis Functional Index (BASFI) at
 Week 24
 -Percentage of Participants who Achieve Ankylosing Spondylitis Disease Activity Score (ASDAS) (CRP) Inactive Disease at Week 24
 |  | 
| E.2.3 | Trial contains a sub-study | Yes | 
| E.2.3.1 | Full title, date and version of each sub-study and their related objectives |  | 
| E.3 | Principal inclusion criteria | 
| Participants must have a diagnosis of definite ankylosing spondylitis (AS), as defined by the modified 1984 New York criteria. The radiographic criterion must be confirmed by a central xray reader and at least 1 clinical criterion must be met - Participants must have symptoms of active disease at screening and at
 baseline, as evidenced by both a Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score of greaterthan or equal to (>=4) and a visual analog scale (VAS) score for total back pain of >=4, each on a scale of 0 to 10
 - Participants with elevated high sensitivity C-reactive protein (hsCRP) level of >=0.300 milligram per deciliter (mg/dL) at screening - Refractory by either lack of benefit or documented intolerance to 1 and no more than 1 anti-TNF(alpha) agent - Inadequate response to at least 2 nonsteroidal anti-inflammatory drugs (NSAIDs) over a 4-week period in total with maximal doses of NSAID(s), or is unable to receive a full 4 weeks of maximal NSAID therapy because of intolerance, toxicity, or contraindications to NSAIDs.
 - Participants with complete ankylosis of the spine are permitted to be included in the study, but will be limited to approximately 10 percent (%) of the study population
 |  | 
| E.4 | Principal exclusion criteria | 
| - Participants who have other inflammatory diseases that might confound the evaluations of benefit from the ustekinumab therapy, including but not limited to, rheumatoid arthritis, systemic lupus erythematosus, or Lyme disease
 - Participants who have received infliximab or infliximab biosimilar, within 12 weeks of the first study agent administration; have received adalimumab, adalimumab biosimilar, or certolizumab pegol within 6 weeks of the first study agent administration; have received etanercept or etanercept biosimilar within 6 weeks of the first study agent administration
 - Participants who have ever received golimumab
 - Participants who are pregnant, nursing, or planning a pregnancy or fathering a child while enrolled in the study or within 5 months after receiving the last administration of study agent
 - Participants who have received any systemic immunosuppressives or disease-modifying antirheumatic drugs (DMARDs) other than methotrexate (MTX), sulfasalazine (SSZ), or hydroxychloroquine (HCQ) within 4 weeks prior to first
 administration of study agent. Medications in these categories include, but are not limited to leflunomide, chloroquine, azathioprine, cyclosporine, mycophenolate mofetil, gold, and penicillamine
 |  | 
| E.5 End points | 
| E.5.1 | Primary end point(s) | 
| The primary endpoint is the proportion of subjects who achieve an ASAS 40 response at Week 24. |  | 
| E.5.1.1 | Timepoint(s) of evaluation of this end point |  | 
| E.5.2 | Secondary end point(s) | 
| To control for multiplicity for the primary endpoint analysis and the major secondary endpoint analyses, the 4 major secondary analyses listed below will be performed sequentially contingent upon the success of the primary statistical analysis in that treatment group comparison. Otherwise, the p-values for the subsequent endpoints will be considered as supportive analyses. The following prespecified order will be used to analyze the major secondary endpoints.
 -The proportion of subjects who achieve an ASAS 20 at Week 24.
 -The proportion of subjects who achieve at least a 50% improvement from baseline in BASDAI at Week 24.
 -The change from baseline in BASFI at Week 24.
 -The proportion of subjects who achieve ASDAS (CRP) inactive disease (<1.3) at Week 24.
 |  | 
| E.5.2.1 | Timepoint(s) of evaluation of this end point |  | 
| E.6 and E.7 Scope of the trial | 
| E.6 | Scope of the trial | 
| E.6.1 | Diagnosis | Yes | 
| E.6.2 | Prophylaxis | Yes | 
| E.6.3 | Therapy | Yes | 
| E.6.4 | Safety | No | 
| E.6.5 | Efficacy | Yes | 
| E.6.6 | Pharmacokinetic | No | 
| E.6.7 | Pharmacodynamic | No | 
| E.6.8 | Bioequivalence | No | 
| E.6.9 | Dose response | Yes | 
| E.6.10 | Pharmacogenetic | Yes | 
| E.6.11 | Pharmacogenomic | Yes | 
| E.6.12 | Pharmacoeconomic | Yes | 
| E.6.13 | Others | No | 
| E.7 | Trial type and phase | 
| E.7.1 | Human pharmacology (Phase I) | No | 
| E.7.1.1 | First administration to humans | No | 
| E.7.1.2 | Bioequivalence study | No | 
| E.7.1.3 | Other | No | 
| E.7.1.3.1 | Other trial type description |  | 
| E.7.2 | Therapeutic exploratory (Phase II) | No | 
| E.7.3 | Therapeutic confirmatory (Phase III) | Yes | 
| E.7.4 | Therapeutic use (Phase IV) | No | 
| E.8 Design of the trial | 
| E.8.1 | Controlled | Yes | 
| E.8.1.1 | Randomised | Yes | 
| E.8.1.2 | Open | No | 
| E.8.1.3 | Single blind | No | 
| E.8.1.4 | Double blind | Yes | 
| E.8.1.5 | Parallel group | No | 
| E.8.1.6 | Cross over | No | 
| E.8.1.7 | Other | No | 
| E.8.2 | Comparator of controlled trial | 
| E.8.2.1 | Other medicinal product(s) | No | 
| E.8.2.2 | Placebo | Yes | 
| E.8.2.3 | Other | No | 
| E.8.2.4 | Number of treatment arms in the trial | 3 | 
| E.8.3 | The trial involves single site in the Member State concerned | No | 
| E.8.4 | The trial involves multiple sites in the Member State concerned | Yes | 
| E.8.4.1 | Number of sites anticipated in Member State concerned | 5 | 
| E.8.5 | The trial involves multiple Member States | Yes | 
| E.8.5.1 | Number of sites anticipated in the EEA | 78 | 
| E.8.6 Trial involving sites outside the EEA | 
| E.8.6.1 | Trial being conducted both within and outside the EEA | Yes | 
| E.8.6.2 | Trial being conducted completely outside of the EEA | No | 
| E.8.6.3 | If E.8.6.1 or E.8.6.2 are Yes, specify the regions in which trial sites are planned | 
| Argentina |  
| Belgium |  
| Brazil |  
| Bulgaria |  
| Canada |  
| Czech Republic |  
| France |  
| Germany |  
| Hungary |  
| Korea, Republic of |  
| Mexico |  
| Poland |  
| Russian Federation |  
| Spain |  
| Taiwan |  
| Ukraine |  
| United States |  | 
| E.8.7 | Trial has a data monitoring committee | Yes | 
| E.8.8 | Definition of the end of the trial and justification where it is not the last
                        visit of the last subject undergoing the trial |  | 
| E.8.9 Initial estimate of the duration of the trial | 
| E.8.9.1 | In the Member State concerned years | 2 | 
| E.8.9.1 | In the Member State concerned months | 8 | 
| E.8.9.1 | In the Member State concerned days |  | 
| E.8.9.2 | In all countries concerned by the trial years | 3 | 
| E.8.9.2 | In all countries concerned by the trial months | 1 |