Participants will receive ustekinumab 45 mg subcutaneously at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants will receive placebo subcutaneously to maintain the blind. At Week 52, participants who achieved inactive disease by ASDAS (ESR) <1.3 at both Week 40 and Week 52 will be re-randomized to receive either placebo or ustekinumab 45 mg every 12 weeks in a blinded fashion. At Week 52, participants who did not achieve inactive disease by ASDAS (ESR) <1.3 at Week 40 or Week 52 will continue receiving ustekinumab 45 mg every 12 weeks through Week 88.

Participants will receive ustekinumab 90 mg subcutaneously at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants will receive placebo subcutaneously to maintain the blind. At Week 52, participants who achieved inactive disease by ASDAS (ESR) <1.3 at both Week 40 and Week 52 will receive either placebo or ustekinumab 90 mg every 12 weeks in a blinded fashion. At Week 52, participants who did not achieve inactive disease by ASDAS (ESR) <1.3 at Week 40 or Week 52 will continue receiving ustekinumab 90 mg every 12 weeks through Week 88.

The BASDAI is used to measure the ankylosing spondylitis (AS) disease severity. It consists of 6 questions: fatigue, spinal pain, arthralgia (joint pain) or swelling, enthesitis (inflammation of tendons and ligaments), and morning stiffness (2 questions: duration and severity). Each question is an easy to answer 10 centimeter (cm) visual analog scale (VAS), with 0 being none, and 10 being very severe. In order to give each of the 5 symptoms equal weight, the mean of the 2 questions about morning stiffness were added to the total of the remaining 4 scores, and the final BASDAI score (ranging 0-10) is the average of the overall total score. Higher BASDAI score indicates more severe AS symptom. 50% improvement in response based on imputed data using treatment failure(consider non-responders at and after treatment failure),early escape rules(consider non-responder at Week 20 and 24), non-responder[NRI] (missing responses at post baseline visit imputed as non-responder).

The BASFI is composed with 10 questions (each question is answered with a visual analogue scale 0-10 cm) to assess the disease severity, including the first 8 questions regarding to functional anatomy related activities and the remaining 2 questions related to daily activities of ankylosing spondylitis participants. Each question is a 10cm VAS with a value between 0 (easy) and 10 (impossible). The final BASFI score is the mean of the 10 scores. The BASFI score is the average of the 10 responses and has a possible minimum value of 0 and a possible maximum value of 10. Higher BASFI score indicates more severe functional limitations of the participant due to AS. Early escape rule was applied (measurement value at Week 20 and Week 24 was set as missing).

ASDAS includes CRP milligram per liter (mg/L); four additional self-reported items (rated on 0-10cm VAS or 0-10 numerical rating scale [NRS]) included total back pain(TBP), duration of morning stiffness (DMS), peripheral pain/swelling and patient global assessment(PGA). ASDAS scores calculated as: ASDAS(CRP) = (0.121*total back pain)+ (0.110*PGA)+ (0.073*peripheral pain/swelling)+ (0.058* DMS)+ (0.579*Ln(CRP+1)). The disease activity, TBP, and peripheral pain/swelling on a numeric rating scale (from 0 (normal) to 10 (very severe)) and DMS on a numeric rating scale (0 to 10, with 0 being none and 10 representing a duration of =>2 hours). Inactive disease is defined as an ASDAS score <1.3. ASDAS (CRP) Inactive Disease is based on imputed data using treatment failure(consider non-responders at and after treatment failure),early escape rules(consider non-responder at Week 20 and 24), NRI (missing responses at post baseline visit imputed as non-responder).

Change from baseline in hsCRP levels was reported. hsCRP is a sensitive laboratory assay for serum levels of C-Reactive Protein, which is a biomarker of inflammation. Early escape rule was applied (measurement value at Week 20 and Week 24 was set as missing). Here 'n' signifies the number of participants who were analyzed at each specified timepoints, for each arm, respectively.

ASAS 20 defined as >= 20% improvement from baseline in 4 individual components of ASAS20: Patient's global assessment (PGA) of disease activity (0 to 10cm; 0=very well,10=very poor), total back pain(0 to 10cm; 0=no pain,10=most severe pain), BASFI (self-assessment represented as mean(0 to10 cm; 0=easy to 10=impossible) of 10 questions, 8 of which relate to functional anatomy and 2 relate to participant's ability to cope with life) and Inflammation (0 to 10cm;0=none,10=very severe).

ASAS 40 defined as improvement of >= 40% from baseline and absolute improvement from baseline of at least 2 on 0 to10cm scale in at least 3 of following 4 domains: Patient's global assessment of disease activity (0 to 10cm; 0=very well,10=very poor),total back pain (0 to 10cm; 0=no pain,10=most severe pain), BASFI (self-assessment represented as mean (0 to 10 cm; 0=easy to 10=impossible) of 10 questions, 8 of which relate to participant's functional anatomy and 2 relate to participant's ability to cope with everyday life), Inflammation (0 to 10cm;0=none,10=very severe); no worsening at all from baseline in remaining domain. ASAS40 response based on imputed data using treatment failure (consider non-responders at and after treatment failure), early escape rules(consider non-responder at Week 20 and 24),non-responder[NRI] (missing responses at post baseline visit imputed as non-responder).

ASAS 20 defined as improvement of >= 20 % from baseline and absolute improvement from baseline of 1 on a 0 to 10 cm scale in at least 3 of following 4 domains: Patient's global assessment of disease activity (0 to 10 cm; 0=very well,10=very poor), total back pain (0 to 10 cm; 0=no pain,10=most severe pain), BASFI (self-assessment represented as mean (0 to 10 cm; 0=easy to 10=impossible) of 10 questions, 8 of which relate to participant's functional anatomy and 2 to participant's ability to cope with everyday life), Inflammation (0 to 10 cm;0=none,10=very severe); absence of deterioration (>= 20% and worsening of at least 1 on a 0 to 10 cm scale) from baseline in remaining domain. ASAS20 response based on imputed data using treatment failure (consider non-responders at and after treatment failure),early escape rules (consider non-responder at Week 20 and 24),non-responder[NRI] (missing responses at post baseline visit imputed as non-responder).

The BASDAI is used to measure the ankylosing spondylitis (AS) disease severity. It consists of 6 questions: fatigue, spinal pain, arthralgia (joint pain) or swelling, enthesitis (inflammation of tendons and ligaments), and morning stiffness (2 questions: duration and severity). Each question is an easy to answer 10 centimeter (cm) visual analog scale (VAS), with 0 being none, and 10 being very severe. In order to give each of the 5 symptoms equal weight, the mean of the 2 questions about morning stiffness will be added to the total of the remaining 4 scores, and the final BASDAI score (ranging 0-10) is the average of the overall total score. Higher BASDAI score indicates more severe AS symptom. 50% improvement in BASDAI based on imputed data using treatment failure(consider non-responders at and after treatment failure),early escape rules(consider non-responder at Week 20 and 24), NRI(missing responses at post baseline visit imputed as non-responders).

The BASFI is composed with 10 questions (each question is answered with a visual analogue scale 0-10 cm) to assess the disease severity, including the first 8 questions regarding to functional anatomy related activities and the remaining 2 questions related to daily activities of AS participants. Each question is a 10cm VAS with a value between 0 (easy) and 10 (impossible). The final BASFI score is the mean of the 10 scores. The BASFI score is the average of the 10 responses and has a possible minimum value of 0 and a possible maximum value of 10. Higher BASFI score indicates more severe functional limitations of the participant due to AS. Missing data were imputed using early escape rule (measurement value at Week 20 and 24 was set as missing). Here 'n' defined as number of participants who were analyzed at each specified timepoint, for each arm, respectively.

ASDAS includes CRP mg/L; four additional self-reported items (rated on 0-10cm VAS or 0-10 numerical rating scale [NRS]) included total back pain(TBP), duration of morning stiffness (DMS), peripheral pain/swelling and patient global assessment(PGA). ASDAS scores calculated as: ASDAS(CRP) = (0.121*total back pain)+ (0.110*PGA)+ (0.073*peripheral pain/swelling)+ (0.058* DMS)+ (0.579*Ln(CRP+1)). The disease activity, TBP, and peripheral pain/swelling on a numeric rating scale (from 0 (normal) to 10 (very severe)) and DMS on a numeric rating scale (0 to 10, with 0 being none and 10 representing a duration of =>2 hours). Inactive disease is defined as an ASDAS score <1.3. ASDAS (CRP) Inactive Disease is based on imputed data using treatment failure(consider non-responders at and after treatment failure),early escape rules(consider non-responder at Week 20 and 24), NRI (missing responses at post baseline visit imputed as non-responder).

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind. At Week 52, all participants who achieved inactive disease (Ankylosing Spondylitis Disease Activity Score [ASDAS] erythrocyte sedimentation rate [ESR] less than [<] 1.3) at both Week 40 and 52 underwent re-randomization to either Ustekinumab or placebo. Participants who did not achieve inactive disease at either Week 40 or 52 received previously assigned ustekinumab dose at their scheduled visits. Last dose was scheduled for Week 88 and last study visit for Week 100.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind. At Week 52, all participants who achieved inactive disease (ASDAS ESR<1.3) at both Week 40 and 52 underwent re-randomization to either Ustekinumab or placebo. Participants who did not achieve inactive disease at either Week 40 or 52 received previously assigned ustekinumab dose at their scheduled visits. Last dose was scheduled for Week 88 and last study visit for Week 100.

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 45 mg SC at Weeks 0 and 4, followed by every 12 weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.

Participants received ustekinumab 90 mg SC at Weeks 0 and 4, followed by every four weeks through Week 52. At Weeks 20 and 24, participants received placebo subcutaneously to maintain the blind.