Trial to Evaluate the Efficacy and Safety of Abatacept in Combination With Standard Therapy Compared to Standard Therapy Alone in Improving Disease Activity in Adults With Active Idiopathic Inflammatory Myopathy

• Sponsor: Bristol-Myers Squibb (Industry)
• Overall Status: Terminated
• CT.gov ID: NCT02971683
• Collaborator: (none)
• Enrollment: 149
• Locations: 76
• Arms: 2
• Actual Duration (Months): 62
• Patients Per Site: 2
• Patients Per Site Per Month: 0

Study Details

Study Description

Brief Summary

Trial to Evaluate the Efficacy and Safety of Abatacept subcutaneous (SC) in Combination With Standard Therapy Compared to Standard Therapy Alone in Improving Disease Activity in Adults With Active Idiopathic Inflammatory Myopathy

Condition or Disease	Intervention/Treatment	Phase
Polymyositis; Dermatomyositis; Autoimmune Necrotizing Myopathy; Overlap Myositis; Juvenile Myositis Above the Age of 18	Drug: Abatacept subcutaneous; Drug: Placebo	Phase 3

Study Design

• Study Type: Interventional
• Actual Enrollment: 149 participants
• Allocation: Randomized
• Intervention Model: Parallel Assignment
• Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
• Primary Purpose: Treatment
• Official Title: A Phase 3, Randomized, Double-Blind Clinical Trial to Evaluate the Efficacy and Safety of Abatacept SC With Standard Treatment Compared to Standard Treatment Alone in Improving Disease Activity in Adults With Active Idiopathic Inflammatory Myopathy (IIM)
• Actual Study Start Date: May 4, 2017
• Actual Primary Completion Date: Jul 27, 2020
• Actual Study Completion Date: Jul 5, 2022

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: Abatacept subcutaneous + Standard Treatment Abatacept subcutaneous weekly in addition to the subject's current standard treatment for 24 weeks followed by a 28 week open-label period of abatacept treatment plus the subject's current standard treatment.	Drug: Abatacept subcutaneous; Specified dose of Abatacept subcutaneous on specified days
Placebo Comparator: Placebo of Abatacept subcutaneous + Standard Treatment Placebo of Abatacept subcutaneous weekly in addition to the subject's current standard treatment for 24 weeks followed by a 28 week open-label period of abatacept treatment plus the subject's current standard treatment.	Drug: Placebo; Placebo of Abatacept subcutaneous

Outcome Measures

Primary Outcome Measures

1. Number of Participants Achieving International Myositis Assessment and Clinical Studies Definition of Improvement (IMACS DOI) at Week 24 Without Rescue [From first dose to 24 weeks after first dose. (Approximately 169 days)]

   The number of participants who achieve IMACS DOI (International Myositis Assessment and Clinical Studies definition of improvement) without rescue medication at week 24. The IMACS DOI is: An improvement of >/= 20% from baseline in 3 IMACS core measures, no more than 2 IMACS core measure scores worsen by >/= 25% from baseline, and no more than 2 IMACS core measure scores worsen by >/= 25% from baseline. IMACS core measures are: Physician Global Assessment of Disease Activity (PGA), Patient (Subject) Global Assessment of Disease Activity (SGA), Manual Muscle Test (MMT-8), Health Assessment Questionnaire-Disability Index (HAQ-DI), Muscle Enzyme levels, Myositis Disease Activity Assessment Tool (MDAAT) Extramuscular Global Activity.

Secondary Outcome Measures

1. Mean Change in Health Assessment Questionnaire-Disability Index (HAQ-DI) From Baseline to Week 24. [From first dose to 24 weeks after first dose. (Approximately 169 days)]

   The adjusted mean change from baseline in the Health Assessment Questionnaire-Disability Index (HAQ-DI). HAQ-DI is a patient-reported outcome measuring disability by asking a total of 20 questions in eight categories of function: dressing, arising, eating, walking, hygiene, reach, grip, and activities. If an aid or device is used or if help is required from another individual, then the minimum score for that section is 2. The highest component score in each category determines the score for the category and scores are averaged to give the disability index. The HAQ scale ranges from 0 (no difficulties) to 3 (unable to do).

2. Mean Change in Muscle Endurance Using the Myositis Function Index (FI-2) From Baseline to Week 24 [From first dose to 24 weeks after first dose. (Approximately 169 days)]

   The adjusted mean change from baseline in Myositis FI-2 scores is assessing muscle endurance impairment by testing specific muscle groups. The 3 Score average includes shoulder flexion, hip flexion, and head lift. Each muscle group is scored as the number of correctly performed repetitions with 60 maximal number of repetitions. The total score is based on hip flexion, shoulder flexion (R/L) and neck divided by 3 (range 0-60 repetitions).

3. Mean Change in Myositis Disease Activity Assessment Tool (MDAAT) Assessment of Extra-muscular From Baseline to Week 24. [From first dose to 24 weeks after first dose. (Approximately 169 days)]

   The adjusted mean change from baseline in the Myositis Disease Activity Assessment Tool (MDAAT) assessment of extra-muscular uses a 100 mm Visual Analog Scale (VAS) scale. This VAS assesses the overall extra-muscular clinical features based upon: 1) The presence of clinical features or symptoms within the previous 4 weeks that are due to active disease. 2) The judgment that the feature is due to the myositis disease process. 3) The concept that disease activity is defined as a potentially reversible finding. 4) A clinical, functional, and laboratory assessments. The scoring is performed by the investigator and ranges from 0 (absent extra-muscular disease activity) to 100 (maximum extra-muscular disease activity).

4. Myositis Response Criteria (MRC) Total Improvement Score From Baseline to Week 24. [From first dose to 24 weeks after first dose. (Approximately 169 days)]

   The Myositis Response Criteria (MRC) is a continuous total improvement score from baseline (range 0-100) based on the sum of the absolute percent change in the 6 core domains (weighted) used in the IMACS DOI (International Myositis Assessment and Clinical Studies definition of improvement) IMACS core measures are: Physician Global Assessment of Disease Activity (PGA), Patient (Subject) Global Assessment of Disease Activity (SGA), Manual Muscle Test (MMT-8), Health Assessment Questionnaire-Disability Index (HAQ-DI), Muscle Enzyme levels, Myositis Disease Activity Assessment Tool (MDAAT) Extramuscular Global Activity. The total improvement score ranges between 0 and 100 percent corresponds to the degree of improvement, with higher scores corresponding to a greater degree of improvement ( >/= 20 represents minimal improvement, a score of >/= 40 represents moderate improvement, and a score of >/= 60 represents major improvement).

5. Number of Participants Experiencing Adverse Events (AE) in the Double-Blind Period [From first dose up to approximately 56 days post last dose date in double-blind period or first dose in open-label period.]

   The number of treated participants experiencing an adverse event. An Adverse Event (AE) is defined as any new untoward medical occurrence or worsening of a preexisting medical condition in participants administered a study drug and that does not necessarily have a causal relationship with the treatment.

6. Number of Participants Experiencing Serious Adverse Events (SAE) in the Double-Blind Period [From first dose up to approximately 56 days post last dose date in double-blind period or first dose in open-label period.]

   The number of treated participants experiencing a Serious Adverse Event (SAE). A Serious Adverse Event (SAE) is any untoward medical occurrence that at any dose: results in death, is life-threatening, requires inpatient hospitalization or causes prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, or is an important medical event.

7. Number of Participants Experiencing Adverse Events (AE) of Special Interest in the Double-Blind Period [From first dose up to approximately 56 days post last dose date in double-blind period or first dose in open-label period.]

   The number of treated participants experiencing adverse events of special interest: infections, malignancies, autoimmune events, local injection site reactions, and systemic injection reactions.

8. Number of Participants Experiencing Laboratory Test Abnormalities in the Double-Blind Period [From first dose up to approximately 56 days post last dose date in double-blind period or first dose in open-label period.]

   The number of participants experiencing laboratory test abnormalities. Laboratory analysis was performed on the following: hematology, liver and kidney function, electrolytes, other chemistry testing (glucose, protein, cardiac), and urine chemistry. Only tests with participants experiencing abnormalities were reported.

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years and Older
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Inclusion Criteria:

-Diagnosis of IIM based on the Bohan and Peter classification criteria: i) Subjects with dermatomyositis (DM) must also have a confirmed myositis-associated rash (Gottron's papules or a heliotrope rash preferably confirmed by skin biopsy) and 2 or more of the remaining 4 criteria.

1. Subjects with a diagnosis of IIM other than DM include PM, autoimmune necrotizing myopathy, myositis in association with another connective tissue disease (overlap myositis) and juvenile myositis subjects above the age of 18. These subjects must have a prior muscle biopsy diagnostic for IIM or a positive test for at least one myositis-specific autoantibody (anti-aminoacyl-tRNA synthetases (Jo-1, PL-7, PL-12, EJ, OJ, KS, Zo, YRS), anti-Mi-2, anti-SRP, anti-TIF1-g, anti-NXP-2, anti-MDA5, anti-SAE, anti-HMGCR). For subjects with overlap myositis, the myositis must be the principal clinically active manifestation of their disease. Where applicable, documentation of prior skin biopsy, muscle biopsy, and autoantibody results must be obtained and retained by the site.

• Demonstrable muscle weakness measured by the MMT-8 of ≤ 135 units and any 3 of the following: i) MMT-8 ≤ 125 units; ii) Physician's global assessment (PGA) visual analog scale (VAS) ≥2 cm; iii) Subject's global assessment (SGA) VAS ≥2 cm; iv) HAQ-DI ≥ 0.5;

1. One or more muscle enzyme (CK, aldolase, LDH, AST, ALT) ³ 1.3 times upper limit of normal (ULN); vi) MDAAT Extramuscular Global Activity VAS ≥2 cm

• Demonstration of currently active IIM will be determined by an adjudication committee unless the subject has any one of the following: i) an active myositis-associated rash (Gottron's papules or heliotrope rash), or ii) a recent (within 3 months prior to signing informed consent) biopsy, magnetic resonance imaging (MRI), or electromyogram (EMG) demonstrating active disease, or iii) an elevated CK > 5 times the upper limit of normal

• Active disease despite prior treatment with corticosteroids, immunosuppressants, or biologics as determined by the investigator

• The subject must be on background standard treatment for IIM. The standard treatments that are allowed as background treatment for IIM includes: i) Corticosteroids alone, or ii) One of the following immunosuppressants: methotrexate, azathioprine, mycophenolate mofetil, tacrolimus, or cyclosporine (combinations of these treatments are not allowed), or iii) A combination of corticosteroids and one of the above immunosuppressants. The subject must have been on the same medication(s) for IIM for 12 weeks prior to randomization and the dose must have been stable for 4 weeks prior to randomization. If using azathioprine, the subject must have been on azathioprine for at least 24 weeks with a stable dose for at least 12 weeks prior to randomization.

Exclusion Criteria:

• Subjects with Inclusion Body Myositis (IBM), or myositis other than IIM, eg, drug-induced myositis and PM associated with HIV

• Subjects treated with penicillamine or zidovudine in the past 3 months

• Subjects treated with rituximab in the 6 months prior to randomization (there must be laboratory results indicating the presence of circulating B cells [CD19+]). Any other biologic treatment in the past 3 months or immune globulin (intravenous [IVIG] or subcutaneous [SCIG]) in the past 3 months prior to randomization

• Subjects with uncontrolled or rapidly progressive interstitial lung disease

• Subjects with severe muscle damage (Myositis Damage Index > 7/10), permanent weakness due to a non-IIM cause, or myositis with cardiac involvement

• Cancer-associated myositis (myositis diagnosed within 2 years of a diagnosis of cancer

• Subjects who are known to be positive for the anti-TIF-1 (p155/140) autoantibody prior to randomization who were diagnosed with IIM < 1 year prior to randomization.

• Subjects at risk for tuberculosis

• Subjects with recent acute infection requiring antibiotics

• Subjects with history of chronic or recurrent bacterial, viral or systemic fungal infections

• Subjects who have a present malignancy or have had a previous malignancy within the last 5 years prior to screening (except for a documented history of cured non-metastatic squamous or basal cell skin carcinoma or cervical carcinoma in situ).

Other protocol-defined inclusion/exclusion criteria apply

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Local Institution - 0015	Phoenix	Arizona	United States	85028
2	Local Institution - 0075	Beverly Hills	California	United States	90211
3	Local Institution - 0012	Orange	California	United States	92868
4	George Washington Medical Faculty Associates	Washington	District of Columbia	United States	20037
5	Local Institution - 0018	Fort Lauderdale	Florida	United States	33309
6	Local Institution - 0013	Miami	Florida	United States	33136
7	Local Institution - 0006	Kansas City	Kansas	United States	66160
8	Harvard Medical School - Brigham and Women's Hospital (BWH) - The Schuster Family Transplantation Re	Boston	Massachusetts	United States	02115
9	Local Institution - 0089	Ann Arbor	Michigan	United States	48109
10	Local Institution - 0002	Eagan	Minnesota	United States	55121
11	Local Institution - 0011	Omaha	Nebraska	United States	68198-3025
12	Dartmouth-Hitchcock Medical Center-Norris Cotton Cancer Center	Lebanon	New Hampshire	United States	03756
13	Local Institution - 0097	New York	New York	United States	10021
14	Local Institution - 0010	Wilmington	North Carolina	United States	28401
15	The Ohio State University Wexner Medical Center (OSUWMC) - CarePoint East	Columbus	Ohio	United States	43210
16	Local Institution - 0094	Middleburg Heights	Ohio	United States	44130
17	Local Institution - 0059	Norman	Oklahoma	United States	73072
18	East Penn Rheumatology Associates, PC	Bethlehem	Pennsylvania	United States	18015
19	Local Institution - 0014	Pittsburgh	Pennsylvania	United States	15213
20	Local Institution - 0005	Orangeburg	South Carolina	United States	29118
21	Local Institution - 0017	Jackson	Tennessee	United States	38305
22	Local Institution - 0096	Austin	Texas	United States	78756
23	Local Institution - 0016	Houston	Texas	United States	77030
24	University of Washington	Seattle	Washington	United States	98195
25	Local Institution	Camperdown	New South Wales	Australia	2050
26	Local Institution - 0053	St Leonards	New South Wales	Australia	2065
27	Local Institution	Auchenflower	Queensland	Australia	4066
28	Local Institution	Murdoch	Western Australia	Australia	6150
29	Local Institution - 0073	Salvador	Bahia	Brazil	40150150
30	Local Institution	Vitoria	Espirito Santo	Brazil	29055-450
31	Local Institution - 0069	Juiz de Fora	Minas Gerais	Brazil	36010570
32	Local Institution - 0072	Porto Alegre	RIO Grande DO SUL	Brazil	90480-000
33	Local Institution - 0074	Bairro Jardim	SAO Paulo	Brazil	09090-790
34	Local Institution - 0067	Rio Grande Do Sul		Brazil	90035-000
35	Local Institution - 0071	Sao Paulo		Brazil	04032-060
36	Local Institution - 0029	Praha 2		Czechia	128 50
37	Local Institution	Brest Cedex		France	29609
38	Local Institution	Lille		France	59037
39	Local Institution - 0044	Strasbourg		France	67098
40	Local Institution	Berlin		Germany	10117
41	Local Institution	Halle (saale)		Germany	06120
42	Local Institution - 0028	Hamburg		Germany	22763
43	Local Institution	Munchen		Germany	80336
44	Local Institution - 0023	Pavia	Lombardia	Italy	27100
45	Local Institution	Ferrara		Italy	44124
46	Local Institution	Firenze		Italy	50139
47	Local Institution	Padova		Italy	35128
48	Local Institution	Pisa		Italy	56126
49	Local Institution - 0091	Kitakyushu	Fukuoka	Japan	807-8555
50	Local Institution - 0090	Sapporo-City	Hokkaido	Japan	060-0011
51	Local Institution - 0078	Sapporo	Hokkaido	Japan	060-8648
52	Local Institution - 0082	Tsukuba	Ibaraki	Japan	3058576
53	Local Institution	Kawasaki-shi	Kanagawa	Japan	2168511
54	Local Institution - 0084	Kumamoto-city	Kumamoto	Japan	8608556
55	Local Institution - 0088	Nagasaki-shi	Nagasaki	Japan	8528501
56	Local Institution	Sasebo city	Nagasaki	Japan	857-1195
57	Local Institution	Iruma-gun	Saitama	Japan	3500495
58	Local Institution - 0079	Bunkyo-ku	Tokyo	Japan	1138603
59	Local Institution	Chuo-ku	Tokyo	Japan	104-8560
60	Local Institution - 0092	Shinjuku-ku	Tokyo	Japan	1608582
61	Local Institution - 0093	Shinjuku-Ku	Tokyo	Japan	1628666
62	Local Institution - 0087	Ube-shi	Yamaguchi	Japan	755-8505
63	Local Institution - 0076	Miyagi		Japan	980-8574
64	Local Institution - 0086	Tokyo		Japan	1138519
65	Local Institution - 0066	Seoul		Korea, Republic of	02447
66	Local Institution - 0065	Seoul		Korea, Republic of	03080
67	Local Institution - 0064	Seoul		Korea, Republic of	04763
68	Local Institution - 0049	Mexico City	Distrito Federal	Mexico	06700
69	Local Institution - 0046	Mexico	Distrito Federal	Mexico	11850
70	Local Institution - 0048	Guadalajara	Jalisco	Mexico	44160
71	Local Institution - 0047	San Luis Potosi		Mexico	78213
72	Local Institution	San Luis Potosi		Mexico	78290
73	Local Institution	Lund		Sweden	22242
74	Local Institution	Orebro		Sweden	70185
75	Local Institution	Stockholm		Sweden	17176
76	Local Institution - 0038	Vasteras		Sweden	72189

Sponsors and Collaborators

• Bristol-Myers Squibb

Investigators

• Study Director: Bristol-Myers Squibb, Bristol-Myers Squibb

Study Documents (Full-Text)

• Study Protocol - Feb 1, 2019
• Statistical Analysis Plan - Dec 15, 2020

More Information

Additional Information:

• BMS Clinical Trial Information
• BMS Clinical Trial Patient Recruiting

Publications

None provided.

• Responsible Party: Bristol-Myers Squibb
• ClinicalTrials.gov Identifier: NCT02971683
• Other Study ID Numbers: IM101-611; 2016-002269-77
• First Posted: Nov 23, 2016
• Last Update Posted: Aug 8, 2022
• Last Verified: Aug 1, 2022

• Studies a U.S. FDA-regulated Drug Product: Yes
• Studies a U.S. FDA-regulated Device Product: No
• Additional relevant MeSH terms: Muscular Diseases; Dermatomyositis; Myositis; Polymyositis; Abatacept

Study Results

Participant Flow

Pre-assignment Detail	148 were randomized and treated

Arm/Group Title	Double-Blind Abatacept	Double-Blind Placebo
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)	Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)
Period Title: Overall Study
STARTED	75	73
COMPLETED	69	65
NOT COMPLETED	6	8

Baseline Characteristics

Arm/Group Title	Double-Blind Abatacept	Double-Blind Placebo	Total
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)	Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)	Total of all reporting groups
Overall Participants	75	73	148
Age (Years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [Years]	49.3 (14.41)	48.1 (14.09)	48.7 (14.22)
Age, Customized (Number) [Number]
16-29 years old	9 12%	9 12.3%	18 12.2%
30-39 years old	8 10.7%	14 19.2%	22 14.9%
40-49 years old	14 18.7%	14 19.2%	28 18.9%
50-59 years old	31 41.3%	19 26%	50 33.8%
>/= 60 years old	13 17.3%	17 23.3%	30 20.3%
Sex: Female, Male (Count of Participants)
Female	52 69.3%	54 74%	106 71.6%
Male	23 30.7%	19 26%	42 28.4%
Ethnicity (NIH/OMB) (Count of Participants)
Hispanic or Latino	7 9.3%	3 4.1%	10 6.8%
Not Hispanic or Latino	19 25.3%	19 26%	38 25.7%
Unknown or Not Reported	49 65.3%	51 69.9%	100 67.6%
Race/Ethnicity, Customized (Number) [Number]
American Indian or Alaska Native	3 4%	3 4.1%	6 4.1%
Asian	10 13.3%	6 8.2%	16 10.8%
Black or African American	9 12%	8 11%	17 11.5%
White	42 56%	42 57.5%	84 56.8%
Japanese	11 14.7%	10 13.7%	21 14.2%
Other	0 0%	3 4.1%	3 2%
Unknown	0 0%	1 1.4%	1 0.7%

Outcome Measures

1. Primary Outcome

Title	Number of Participants Achieving International Myositis Assessment and Clinical Studies Definition of Improvement (IMACS DOI) at Week 24 Without Rescue
Description	The number of participants who achieve IMACS DOI (International Myositis Assessment and Clinical Studies definition of improvement) without rescue medication at week 24. The IMACS DOI is: An improvement of >/= 20% from baseline in 3 IMACS core measures, no more than 2 IMACS core measure scores worsen by >/= 25% from baseline, and no more than 2 IMACS core measure scores worsen by >/= 25% from baseline. IMACS core measures are: Physician Global Assessment of Disease Activity (PGA), Patient (Subject) Global Assessment of Disease Activity (SGA), Manual Muscle Test (MMT-8), Health Assessment Questionnaire-Disability Index (HAQ-DI), Muscle Enzyme levels, Myositis Disease Activity Assessment Tool (MDAAT) Extramuscular Global Activity.
Time Frame	From first dose to 24 weeks after first dose. (Approximately 169 days)

Outcome Measure Data

Analysis Population Description

All treated participants excluding participants with relevant protocol deviations

Arm/Group Title	Double-Blind Abatacept	Double-Blind Placebo
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)	Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)
Measure Participants	75	73
Count of Participants [Participants]	42 56%	31 42.5%

Statistical Analysis 1

Statistical Analysis Overview	Comparison Group Selection	Double-Blind Abatacept
	Comments
	Type of Statistical Test	Superiority
	Comments
Statistical Test of Hypothesis	p-Value	0.083
	Comments
	Method	Regression, Logistic
	Comments
Method of Estimation	Estimation Parameter	Odds Ratio (OR)
	Estimated Value	1.8
	Confidence Interval	(2-Sided) 95%; 0.9 to 3.5
	Parameter Dispersion	Type: Value:
	Estimation Comments

2. Secondary Outcome

Title	Mean Change in Health Assessment Questionnaire-Disability Index (HAQ-DI) From Baseline to Week 24.
Description	The adjusted mean change from baseline in the Health Assessment Questionnaire-Disability Index (HAQ-DI). HAQ-DI is a patient-reported outcome measuring disability by asking a total of 20 questions in eight categories of function: dressing, arising, eating, walking, hygiene, reach, grip, and activities. If an aid or device is used or if help is required from another individual, then the minimum score for that section is 2. The highest component score in each category determines the score for the category and scores are averaged to give the disability index. The HAQ scale ranges from 0 (no difficulties) to 3 (unable to do).
Time Frame	From first dose to 24 weeks after first dose. (Approximately 169 days)

Outcome Measure Data

Analysis Population Description

All treated participants with both baseline and post-baseline measurements

Arm/Group Title	Double-Blind Abatacept	Double-Blind Placebo
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)	Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)
Measure Participants	66	62
Mean (Standard Error) [Score on a scale]	-0.31 (0.067)	-0.20 (0.069)

3. Secondary Outcome

Title	Mean Change in Muscle Endurance Using the Myositis Function Index (FI-2) From Baseline to Week 24
Description	The adjusted mean change from baseline in Myositis FI-2 scores is assessing muscle endurance impairment by testing specific muscle groups. The 3 Score average includes shoulder flexion, hip flexion, and head lift. Each muscle group is scored as the number of correctly performed repetitions with 60 maximal number of repetitions. The total score is based on hip flexion, shoulder flexion (R/L) and neck divided by 3 (range 0-60 repetitions).
Time Frame	From first dose to 24 weeks after first dose. (Approximately 169 days)

Outcome Measure Data

Analysis Population Description

All treated participants with both baseline and post-baseline measurements

Arm/Group Title	Double-Blind Abatacept	Double-Blind Placebo
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)	Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)
Measure Participants	59	58
Mean (Standard Error) [Number of repetitions]	4.1 (1.33)	1.2 (1.38)

4. Secondary Outcome

Title	Mean Change in Myositis Disease Activity Assessment Tool (MDAAT) Assessment of Extra-muscular From Baseline to Week 24.
Description	The adjusted mean change from baseline in the Myositis Disease Activity Assessment Tool (MDAAT) assessment of extra-muscular uses a 100 mm Visual Analog Scale (VAS) scale. This VAS assesses the overall extra-muscular clinical features based upon: 1) The presence of clinical features or symptoms within the previous 4 weeks that are due to active disease. 2) The judgment that the feature is due to the myositis disease process. 3) The concept that disease activity is defined as a potentially reversible finding. 4) A clinical, functional, and laboratory assessments. The scoring is performed by the investigator and ranges from 0 (absent extra-muscular disease activity) to 100 (maximum extra-muscular disease activity).
Time Frame	From first dose to 24 weeks after first dose. (Approximately 169 days)

Outcome Measure Data

Analysis Population Description

All treated participants with both baseline and post-baseline measurements

Arm/Group Title	Double-Blind Abatacept	Double-Blind Placebo
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)	Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)
Measure Participants	63	60
Mean (Standard Error) [Score on a scale]	-1.56 (0.202)	-1.40 (0.208)

5. Secondary Outcome

Title	Myositis Response Criteria (MRC) Total Improvement Score From Baseline to Week 24.
Description	The Myositis Response Criteria (MRC) is a continuous total improvement score from baseline (range 0-100) based on the sum of the absolute percent change in the 6 core domains (weighted) used in the IMACS DOI (International Myositis Assessment and Clinical Studies definition of improvement) IMACS core measures are: Physician Global Assessment of Disease Activity (PGA), Patient (Subject) Global Assessment of Disease Activity (SGA), Manual Muscle Test (MMT-8), Health Assessment Questionnaire-Disability Index (HAQ-DI), Muscle Enzyme levels, Myositis Disease Activity Assessment Tool (MDAAT) Extramuscular Global Activity. The total improvement score ranges between 0 and 100 percent corresponds to the degree of improvement, with higher scores corresponding to a greater degree of improvement ( >/= 20 represents minimal improvement, a score of >/= 40 represents moderate improvement, and a score of >/= 60 represents major improvement).
Time Frame	From first dose to 24 weeks after first dose. (Approximately 169 days)

Outcome Measure Data

Analysis Population Description

All treated participants with both baseline and post-baseline measurements

Arm/Group Title	Double-Blind Abatacept	Double-Blind Placebo
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)	Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)
Measure Participants	62	58
Mean (Standard Error) [Score on a scale]	40.83 (2.873)	37.22 (2.963)

6. Secondary Outcome

Title	Number of Participants Experiencing Adverse Events (AE) in the Double-Blind Period
Description	The number of treated participants experiencing an adverse event. An Adverse Event (AE) is defined as any new untoward medical occurrence or worsening of a preexisting medical condition in participants administered a study drug and that does not necessarily have a causal relationship with the treatment.
Time Frame	From first dose up to approximately 56 days post last dose date in double-blind period or first dose in open-label period.

Outcome Measure Data

Analysis Population Description

All treated participants

Arm/Group Title	Double-Blind Abatacept	Double-Blind Placebo
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)	Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)
Measure Participants	75	73
Count of Participants [Participants]	52 69.3%	55 75.3%

7. Secondary Outcome

Title	Number of Participants Experiencing Serious Adverse Events (SAE) in the Double-Blind Period
Description	The number of treated participants experiencing a Serious Adverse Event (SAE). A Serious Adverse Event (SAE) is any untoward medical occurrence that at any dose: results in death, is life-threatening, requires inpatient hospitalization or causes prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, or is an important medical event.
Time Frame	From first dose up to approximately 56 days post last dose date in double-blind period or first dose in open-label period.

Outcome Measure Data

Analysis Population Description

All treated participants

Arm/Group Title	Double-Blind Abatacept	Double-Blind Placebo
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)	Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)
Measure Participants	75	73
Count of Participants [Participants]	4 5.3%	4 5.5%

8. Secondary Outcome

Title	Number of Participants Experiencing Adverse Events (AE) of Special Interest in the Double-Blind Period
Description	The number of treated participants experiencing adverse events of special interest: infections, malignancies, autoimmune events, local injection site reactions, and systemic injection reactions.
Time Frame	From first dose up to approximately 56 days post last dose date in double-blind period or first dose in open-label period.

Outcome Measure Data

Analysis Population Description

All treated participants

Arm/Group Title	Double-Blind Abatacept	Double-Blind Placebo
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)	Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)
Measure Participants	75	73
Infections	19 25.3%	31 42.5%
Malignancies	0 0%	0 0%
Autoimmune Disorders	2 2.7%	3 4.1%
Systemic Injection Reactions	4 5.3%	5 6.8%
Local Injection Site Reactions	1 1.3%	0 0%

9. Secondary Outcome

Title	Number of Participants Experiencing Laboratory Test Abnormalities in the Double-Blind Period
Description	The number of participants experiencing laboratory test abnormalities. Laboratory analysis was performed on the following: hematology, liver and kidney function, electrolytes, other chemistry testing (glucose, protein, cardiac), and urine chemistry. Only tests with participants experiencing abnormalities were reported.
Time Frame	From first dose up to approximately 56 days post last dose date in double-blind period or first dose in open-label period.

Outcome Measure Data

Analysis Population Description

All treated participants

Arm/Group Title	Double-Blind Abatacept	Double-Blind Placebo
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)	Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)
Measure Participants	75	73
LOW LEUKOCYTES	1 1.3%	0 0%
HIGH LEUKOCYTES	2 2.7%	4 5.5%
HIGH EOSINOPHILS (ABSOLUTE)	3 4%	2 2.7%
LOW LYMPHOCYTES (ABSOLUTE)	17 22.7%	14 19.2%
LOW NEUTROPHILS + BANDS (ABSOLUTE)	1 1.3%	0 0%
HIGH ALANINE AMINOTRANSFERASE (ALT)	1 1.3%	1 1.4%
HIGH ASPARTATE AMINOTRANSFERASE (AST)	0 0%	1 1.4%
HIGH G-GLUTAMYL TRANSFERASE (GGT)	4 5.3%	1 1.4%
HIGH BLOOD UREA NITROGEN	0 0%	1 1.4%
HIGH CREATININE	3 4%	3 4.1%
HIGH CALCIUM, TOTAL	1 1.3%	0 0%
LOW PHOSPHORUS, INORGANIC	0 0%	1 1.4%
HIGH PHOSPHORUS, INORGANIC	1 1.3%	0 0%
HIGH SODIUM, SERUM	0 0%	1 1.4%
LOW GLUCOSE, SERUM	4 5.3%	3 4.1%
HIGH GLUCOSE, SERUM	8 10.7%	8 11%
HIGH PROTEIN, TOTAL	0 0%	1 1.4%
HIGH CREATINE KINASE (CK)	0 0%	4 5.5%
HIGH LACTATE DEHYDROGENASE (LD)	0 0%	1 1.4%

Adverse Events

Time Frame	From first dose to 100 days post last dose (up to 3 years, 8 months)
Arm/Group Title	DOUBLE-BLIND ABATACEPT		DOUBLE-BLIND PLACEBO
Arm/Group Description	Subcutaneous abatacept (125 mg weekly) in combination with standard treatment for 24 weeks (6 months)		Placebo to match subcutaneous abatacept in combination with standard treatment for 24 weeks (6 months)
All Cause Mortality
	DOUBLE-BLIND ABATACEPT		DOUBLE-BLIND PLACEBO
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/75 (0%)		1/73 (1.4%)
Serious Adverse Events
	DOUBLE-BLIND ABATACEPT		DOUBLE-BLIND PLACEBO
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	4/75 (5.3%)		4/73 (5.5%)
Gastrointestinal disorders
Vomiting	0/75 (0%)		1/73 (1.4%)
Infections and infestations
Cellulitis	1/75 (1.3%)		0/73 (0%)
Gastroenteritis	1/75 (1.3%)		0/73 (0%)
Herpes zoster	0/75 (0%)		1/73 (1.4%)
Urinary tract infection	1/75 (1.3%)		0/73 (0%)
Musculoskeletal and connective tissue disorders
Polymyositis	0/75 (0%)		1/73 (1.4%)
Renal and urinary disorders
Renal failure	1/75 (1.3%)		0/73 (0%)
Respiratory, thoracic and mediastinal disorders
Acute respiratory failure	0/75 (0%)		1/73 (1.4%)
Other (Not Including Serious) Adverse Events
	DOUBLE-BLIND ABATACEPT		DOUBLE-BLIND PLACEBO
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	7/75 (9.3%)		20/73 (27.4%)
Infections and infestations
Influenza	1/75 (1.3%)		6/73 (8.2%)
Nasopharyngitis	2/75 (2.7%)		8/73 (11%)
Injury, poisoning and procedural complications
Fall	2/75 (2.7%)		4/73 (5.5%)
Nervous system disorders
Headache	2/75 (2.7%)		7/73 (9.6%)

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

Principal Investigators are NOT employed by the organization sponsoring the study.

Bristol-Myers Squibb Co. agreements with investigators vary; constant is our right to embargo communications regarding trial results prior to public release for a period ≤60 days from submittal for review. We will not prohibit investigators from publishing, but will prohibit the disclosure of previously undisclosed confidential information other than study results, and request postponement of single-center publications until after disclosure of the clinical trial's primary publication.