An Investigational Study to Evaluate Experimental Medication BMS-986165 Compared to Placebo and a Currently Available Treatment in Participants With Moderate-to-Severe Plaque Psoriasis

The Number of Participants Who Achieve a 90% Improvement From Baseline in the Psoriasis Area and Severity Index Score at Week 16 (PASI 90)

The Psoriasis Area and Severity Index (PASI) is a quantitative rating scale for measuring the severity of psoriatic lesions based on area coverage and plaque appearance. The PASI is a measure of the average erythema (redness), infiltration (thickness), and desquamation (scaling) of psoriatic skin lesions (each graded on a 0-4 scale), weighted by the area of involvement (head, arms, trunk to groin, and legs to top of buttocks). PASI produces a numeric score that can range from 0 to 72, with higher PASI scores denoting more severe disease activity. PASI 90 is the response as a number of participants who experience at least a 90% improvement in PASI score as compared with the baseline value using the non-responder imputation (NRI) method. Baseline is defined as the measurement at the randomization visit (Week 0). Non-responder imputation (NRI) will be used for participants who: Discontinue treatment or study prior to Week 16 or who have missing Week 16 endpoint data for any reason.

Time frame: Baseline and Week 16

The Number of Participants Who Achieve a 100% Improvement From Baseline in the Psoriasis Area and Severity Index Score at Week 16 (PASI 100)

The Psoriasis Area and Severity Index (PASI) is a quantitative rating scale for measuring the severity of psoriatic lesions based on area coverage and plaque appearance. The PASI is a measure of the average erythema (redness), infiltration (thickness), and desquamation (scaling) of psoriatic skin lesions (each graded on a 0-4 scale), weighted by the area of involvement (head, arms, trunk to groin, and legs to top of buttocks). PASI produces a numeric score that can range from 0 to 72, with higher PASI scores denoting more severe disease activity. PASI 100 is the response as a number of participants who experience at least a 100% improvement in PASI score as compared with the baseline value using the non-responder imputation (NRI) method. Baseline is defined as the measurement at the randomization visit (Week 0). Non-responder imputation (NRI) will be used for participants who: Discontinue treatment or study prior to Week 16 or who have missing Week 16 endpoint data for any reason.

Time frame: Baseline and Week 16

The Number of Participants With a Static Physician Global Assessment Score of 0 at Week 16 (sPGA 0)

The sPGA is a 5-point scale average assessment of all psoriatic lesions graded for erythema, scale, and induration. The sPGA measure determines psoriasis severity at a single point in time (without taking into account the baseline disease condition) as: clear (0), almost clear (1), mild (2), moderate (3), or severe (4). The average of the 3 scales, which is rounded to the nearest whole number, is the final sPGA score. sPGA 0 is the response as a number of participants who experience a sPGA score that determines psoriasis severity as 0 using the non-responder imputation (NRI) method. Non-responder imputation (NRI) will be used for participants who: Discontinue treatment or study prior to Week 16 or who have missing Week 16 endpoint data for any reason.

Time frame: Week 16

Change From Baseline in Psoriasis Symptoms and Signs Diary (PSSD) Symptom Score at Week 16

PSSD assesses the severity of 5 symptoms (itch, pain, stinging, burning, skin tightness) and 6 participant-observed signs (skin dryness, cracking, scaling, shedding or flaking, redness, bleeding). The severity of each item is rated on an 11-point numeric rating scale ranging from 0 (absent) to 10 (worst imaginable). Both symptom and sign scores are derived by averaging the questions and multiplying by 10. A total PSSD score ranging 0-100 will be derived from taking the average of the symptom and sign scores. 0 represents the least severe symptom/sign and 100 represents the most severe. Baseline is defined as the measurement at the randomization visit (Week 0). A modified observation carried forward (mBOCF) approach will be used for missing data. The baseline observation will be carried forward for participants who discontinue study treatment for all analysis weeks after the assessment time point of discontinuation due to lack of efficacy and AEs.

Time frame: Baseline and Week 16

Psoriasis Symptoms and Signs Diary (PSSD) Symptom Score of 0 at Week 16

Psoriasis Symptoms and Signs Diary (PSSD) is an 11-item participant-reported instrument that assesses severity of symptoms and participant-observed signs commonly associated in plaque psoriasis. The PSSD assesses severity of 5 symptoms (itch, pain, stinging, burning, skin tightness) and 6 participant-observed signs (skin dryness, cracking, scaling, shedding or flaking, redness, bleeding) using 0 to 10 numerical ratings. The severity of each item is rated on an 11-point numeric rating scale ranging from 0 (absent) to 10 (worst imaginable) where the symptoms summary score is derived from the average of the scores. A higher score indicates more severe disease. PSSD 0 is the response as a number of participants who experience a PSSD symptom score that determines psoriasis severity as 0 among participants with a baseline PSSD symptom score \>= 1 using the non-responder imputation (NRI) method.

Time frame: Week 16

The Number of Participants With a Scalp Specific Physician's Global Assessment (Ss-PGA) Score 0 or 1 at Week 16 (Ss-PGA 0/1)

The scalp specific Physician's Global Assessment (ss-PGA) evaluates scalp lesions in terms of clinical signs of redness, thickness, and scaliness and scored on the following 5-point ss-PGA scale: 0 = absence of disease, 1 = very mild disease, 2 = mild disease, 3 = moderate disease, 4 = severe disease. ss-PGA 0/1 is the response as a number of participants who experience a ss-PGA score of 0 or 1 with at least a 2-point improvement from baseline among participants with a baseline ss-PGA score ≥3 . Non-responder imputation (NRI) will be used for participants who: Discontinue treatment or study prior to Week 16 or who have missing Week 16 endpoint data for any reason.

Time frame: Week 16

The Number of Participants With a Dermatology Life Quality Index (DLQI) Score of 0 or 1 in Participants Receiving BMS-986165 Compared to Placebo at Week 16 (DLQI 0/1)

The DLQI is a participant-reported quality of life index which consists of 10 questions concerning how much skin problems affect symptoms and feelings, daily activities, leisure, work, school, personal relationships, and treatment during the last week. Each question is scored on a scale of 0 to 3 where 0 = not at all, 1 =a little, 2 = a lot, or 3 = very much. The scores are summed, giving a range from 0 (no impairment of life quality) to 30 (maximum impairment). DLQI 0/1 is the number of participants with a score of 0 or 1 among participants with a baseline DLQI score ≥2. Non-responder imputation (NRI) will be used for participants who: Discontinue treatment or study prior to Week 16 or who have missing Week 16 endpoint data for any reason.

Time frame: Week 16

The Number of Participants With a Physician Global Assessment- Fingernails (PGA-F) Score of 0 or 1 in Participants Receiving BMS-986165 Compared to Placebo at Week 16 (PGA-F 0/1)

The Physician Global Assessment- Fingernails (PGA-F) evaluates the overall condition of the fingernails and is rated on a 5-point scale:0 = clear, 1 = minimal, 2 = mild, 3 = moderate, and 4 = severe. PGA-F 0/1 is the response as a number of participants with a PGA-F score of 0 or 1 with at least a 2-point improvement from baseline among participants with a baseline PGA-F score \>=3. Non-responder imputation (NRI) will be used for participants who: Discontinue treatment or study prior to Week 16 or who have missing Week 16 endpoint data for any reason.

Time frame: Week 16

The Number of Participants With a Palmoplantar Physician's Global Assessment (Pp-PGA) Score of 0 or 1 at Week 16 (Pp-PGA 0/1)

The palmoplantar Physician's Global Assessment (pp-PGA) score evaluates palmoplantar (including finger and toe surfaces) psoriasis lesions based on overall severity by investigator, then scored on the following 5-point scale: 0 = clear; 1 = almost clear; 2 = mild; 3 = moderate; and 4 = severe. pp-PGA 0/1 is the number of participants with a score of 0 or 1 among participants with a baseline pp-PGA score ≥ 3.

Time frame: Week 16

The Number of Participants Who Achieve a 75% Improvement From Baseline in the Psoriasis Area and Severity Index (PASI) Score in Participants Receiving BMS-986165 Compared to Apremilast at Week 16 (PASI 75)

The Psoriasis Area and Severity Index (PASI) is a quantitative rating scale for measuring the severity of psoriatic lesions based on area coverage and plaque appearance. The PASI is a measure of the average erythema (redness), infiltration (thickness), and desquamation (scaling) of psoriatic skin lesions (each graded on a 0-4 scale), weighted by the area of involvement (head, arms, trunk to groin, and legs to top of buttocks). PASI produces a numeric score that can range from 0 to 72, with higher PASI scores denoting more severe disease activity. PASI 75 is the response as a number of participants who experience at least a 75% improvement in PASI score as compared with the baseline value using the non-responder imputation (NRI) method. Baseline is defined as the measurement at the randomization visit (Week 0). Non-responder imputation (NRI) will be used for participants who: Discontinue treatment or study prior to Week 16 or who have missing Week 16 endpoint data for any reason.

Time frame: Baseline and Week 16

The Number of Participants With a Static Physician Global Assessment (sPGA) Score of 0 or 1 in Participants Receiving BMS-986165 Compared to Apremilast at Week 16 (sPGA 0/1)

The sPGA is a 5-point scale average assessment of all psoriatic lesions graded for erythema, scale, and induration. The sPGA measure determines psoriasis severity at a single point in time (without taking into account the baseline disease condition) as: clear (0), almost clear (1), mild (2), moderate (3), or severe (4). The average of the 3 scales, which is rounded to the nearest whole number, is the final sPGA score. sPGA 0/1 is the number of participants with a sPGA score of 0 or 1 with at least a 2-point improvement from baseline. Non-responder imputation (NRI) will be used for participants who: Discontinue treatment or study prior to Week 16 or who have missing Week 16 endpoint data for any reason.

Time frame: Week 16

Time to Relapse Until Week 52 Among Week 24 PASI 75 Responders

Relapse is defined as 50% loss or greater of Week 24 PASI percent improvement from baseline. The PASI is a measure of the average redness, thickness, and scaliness of psoriatic skin lesions (each graded on a 0-4 scale), weighted by the area of involvement (head, arms, trunk to groin, and legs to top of buttocks). PASI produces a numeric score that can range from 0 to 72, with higher PASI scores denoting more severe disease activity.

Time frame: From Week 24 to Week 52 (up to approximately 28 weeks)

The Number of Participants With a Static Physician Global Assessment (sPGA) Score of 0 or 1 in Participants Receiving BMS-986165 Compared to Apremalist at Week 24 (sPGA 0/1)

The sPGA is a 5-point scale average assessment of all psoriatic lesions graded for erythema, scale, and induration. The sPGA measure determines psoriasis severity at a single point in time (without taking into account the baseline disease condition) as: clear (0), almost clear (1), mild (2), moderate (3), or severe (4). The average of the 3 scales, which is rounded to the nearest whole number, is the final sPGA score. sPGA 0/1 is the number of participants with a sPGA score of 0 or 1. Non-responder imputation (NRI) will be used for participants who: Discontinue treatment or study prior to Week 24 or who have missing Week 24 endpoint data for any reason.

Time frame: Week 24

The Number of Participants Who Achieve a 75% Improvement From Baseline in the Psoriasis Area and Severity Index (PASI) Score in Participants Receiving BMS-986165 Compared to Apremalist at Week 24 (PASI 75)

The Psoriasis Area and Severity Index (PASI) is a quantitative rating scale for measuring the severity of psoriatic lesions based on area coverage and plaque appearance. PASI is a measure of the average erythema (redness), infiltration (thickness), and desquamation (scaling) of psoriatic skin lesions (each graded on a 0-4 scale), weighted by the area of involvement (head, arms, trunk to groin, and legs to top of buttocks). PASI produces a numeric score that can range from 0 to 72, with higher PASI scores denoting more severe disease activity. PASI 75 is the response as a number of participants who experience at least a 75% improvement in PASI score as compared with the baseline value using the non-responder imputation (NRI) method. Baseline is defined as the measurement at the randomization visit (Week 0). Non-responder imputation (NRI) will be used for participants who: Discontinue treatment or study prior to Week 24 or who have missing Week 24 endpoint data for any reason.

Time frame: Baseline and Week 24

The Number of Participants Who Achieve a 90% Improvement From Baseline in the Psoriasis Area and Severity Index Score in Participants Receiving BMS-986165 Compared to Apremilast at Week 24 (PASI 90)

The Psoriasis Area and Severity Index (PASI) is a quantitative rating scale for measuring the severity of psoriatic lesions based on area coverage and plaque appearance. PASI is a measure of the average erythema (redness), infiltration (thickness), and desquamation (scaling) of psoriatic skin lesions (each graded on a 0-4 scale), weighted by the area of involvement (head, arms, trunk to groin, and legs to top of buttocks). PASI produces a numeric score that can range from 0 to 72, with higher PASI scores denoting more severe disease activity. PASI 90 is the response as a number of participants who experience at least a 90% improvement in PASI score as compared with the baseline value using the non-responder imputation (NRI) method. Baseline is defined as the measurement at the randomization visit (Week 0). Non-responder imputation (NRI) will be used for participants who: Discontinue treatment or study prior to Week 24 or who have missing Week 24 endpoint data for any reason.

Time frame: Baseline and week 24