A Study to Continue ASP015K Treatment to Rheumatoid Arthritis Patients Who Completed Phase IIb Study or Phase III Study of ASP015K

AE was defined as any untoward medical occurrence in a participant administered a study drug that did not necessarily have a causal relationship to this treatment. An AE could therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom or disease temporally associated with the use of a study drug, whether or not related to the study drug.

ACR20 response: greater than or equal to (≥) 20 percent (%) improvement in tender or swollen joint count; and ≥ 20% improvement in at least 3 of the following 5 criteria: 1) physician's global assessment of disease activity, 2) participant's assessment of disease activity, 3) participant's assessment of pain, 4) participant's assessment of functional disability via a health assessment questionnaire, and 5) C-reactive protein at each visit.

EOT was defined as end of treatment i.e, either early termination (ET) or week 372. EOS was defined as end of study i.e. 28days from EOT.

ACR50 response: ≥50% improvement in tender or swollen joint counts and 50% improvement in 3 of the following 5 criteria: 1) physician's global assessment of disease activity, 2) participant's assessment of disease activity, 3) participant's assessment of pain, 4) participant's assessment of functional ability via a health assessment questionnaire-Disability Index, and 5) C-reactive protein at each visit.

ACR70 response: ≥ 70% improvement in tender or swollen joint counts and 70% improvement in 3 of the following 5 criteria: 1) physician's global assessment of disease activity, 2) participant's assessment of disease activity, 3) participant's assessment of pain, 4) participant's assessment of functional ability via a health assessment questionnaire-Disability Index, and 5) C-reactive protein at each visit.

ACR20 response: ≥20% improvement in tender or swollen joint count; and ≥ 20% improvement in at least 3 of the following 5 criteria: 1) physician's global assessment of disease activity, 2) participant's assessment of disease activity, 3) participant's assessment of pain, 4) participant's assessment of functional disability via a health assessment questionnaire, and 5) ESR at each visit.

ACR50 response: ≥50% improvement in tender or swollen joint counts and 50% improvement in 3 of the following 5 criteria: 1) physician's global assessment of disease activity, 2) participant's assessment of disease activity, 3) participant's assessment of pain, 4) participant's assessment of functional ability via a health assessment questionnaire-Disability Index, and 5) ESR at each visit.

ACR70 response: ≥ 70% improvement in tender or swollen joint counts and 70% improvement in 3 of the following 5 criteria: 1) physician's global assessment of disease activity, 2) participant's assessment of disease activity, 3) participant's assessment of pain, 4) participant's assessment of functional ability via a health assessment questionnaire-Disability Index, and 5) ESR at each visit.

DAS28-CRP response consisted of following parameters: TJC (28 joints), SJC (28 joints), CRP, SGA, and calculated according to description: DAS28 = 0.56√(TJC) + 0.28√(SJC) + 0.36 ln (CRP + 1) + 0.014 × SGA + 0.96. DAS28-CRP scores range from 0.96 to approximately 10. Higher DAS28 score indicated greater disease activity.

DAS28-ESR response consisted of following parameters: TJC (28 joints), SJC (28 joints), ESR, SGA, and calculated according to description: DAS28 = 0.56√(TJC) + 0.28√(SJC) + 0.70 ln ESR + 0.014 × SGA. DAS28-ESR scores range from 0 to approximately 10. Higher DAS28 score indicated greater disease activity.

DAS28-CRP response consisted of following parameters: TJC (28 joints), SJC (28 joints), CRP, SGA, and calculated according to description: DAS28 = 0.56√(TJC) + 0.28√(SJC) + 0.36 ln (CRP + 1) + 0.014 × SGA + 0.96. DAS28-CRP scores range from 0.96 to approximately 10. Higher DAS28 score indicated greater disease activity. DAS28-CRP <2.6 = remission, DAS28-CRP <= 3.2 implied low disease activity and >3.2 to 5.1 implied moderate to high disease activity.

DAS28-ESR response consisted of following parameters: TJC (28 joints), SJC (28 joints), ESR, SGA , and calculated according to description: DAS28 = 0.56√(TJC) + 0.28√(SJC) + 0.70 ln ESR + 0.014 × SGA. DAS28-ESR scores range from 0 to approximately 10. Higher DAS28 score indicated greater disease activity. DAS28-ESR <2.6 = remission, DAS28-ESR <= 3.2 implied low disease activity and >3.2 to 5.1 implied moderate to high disease activity.

DAS28-CRP response consisted of following parameters: TJC (28 joints), SJC (28 joints), CRP, SGA, and calculated according to description: DAS28 = 0.56√(TJC) + 0.28√(SJC) + 0.36 ln (CRP + 1) + 0.014 × SGA + 0.96. DAS28-CRP scores range from 0.96 to approximately 10. Higher DAS28 score indicated greater disease activity. DAS28-CRP <2.6 = remission.

DAS28-ESR response consisted of following parameters: TJC (28 joints), SJC (28 joints), ESR, SGA, and calculated according to description: DAS28 = 0.56√(TJC) + 0.28√(SJC) + 0.70 ln ESR + 0.014 × SGA. DAS28-ESR scores range from 0 to approximately 10. Higher DAS28 score indicated greater disease activity. DAS28-ESR <2.6 = remission.

The participants were examined for the tender joints and the location was confirmed by the investigator who assessed the following 68 joints which included temporomandibular joints (2), sternoclavicular joints (2), acromioclavicular joints (2), shoulder joints (2), elbow joints (2), wrist joints (2), distal interphalangeal joints (8), proximal interphalangeal joints of both hands (10), metacarpophalangeal joints (10), hip joints (2), knee joints (2), ankle joints (2), tarsal bones (2), metatarsophalangeal joints (10), interphalangeal joint joints of toes (2), proximal interphalangeal joints of both feet (8). Higher TJC indicated greater disease activity.

The participants were examined for the swollen joints and the location was confirmed by the investigator who assessed the following 66 joints which included temporomandibular joints (2), sternoclavicular joints (2), acromioclavicular joints (2), shoulder joints (2), elbow joints (2), wrist joints (2), distal interphalangeal joints (8), proximal interphalangeal joints of both hands (10), metacarpophalangeal joints (10), knee joints (2), ankle joints (2), tarsal bones (2), metatarsophalangeal joints (10), interphalangeal joint joints of toes (2), proximal interphalangeal joints of both feet (8). Higher SJC indicated greater disease activity.

Higher CRP indicates greater disease activity.

Higher ESR indicates greater disease activity.

ACR/EULAR Remission was defined as TJC (68 joints) ≤ 1, SJC (66 joints) ≤1, CRP ≤1 mg/dL, and participant's global assessment of arthritis ≤ 1 cm (on a visual analog scale (VAS) of 0 - 100 mm).

The Disease Activity Score Based on 28-joints Count based EULAR response criteria were used to measure individual response as none, good, and moderate, depending on the extent of change from baseline and the level of disease activity reached. Good responders: change from baseline >1.2 with DAS28 =< 3.2; moderate responders: change from baseline >1.2 with DAS28 >3.2 to =<5.1 or change from baseline >0.6 to =<1.2 with DAS28 =<5.1; non-responders: change from baseline =< 0.6 or change from baseline >0.6 and =<1.2 with DAS28 >5.1. Percentage of participants with good response have been reported in this outcome measure.

The Disease Activity Score Based on 28-joints Count based EULAR response criteria were used to measure individual response as none, good, and moderate, depending on the extent of change from baseline and the level of disease activity reached. Good responders: change from baseline >1.2 with DAS28 =< 3.2; moderate responders: change from baseline >1.2 with DAS28 >3.2 to =<5.1 or change from baseline >0.6 to =<1.2 with DAS28 =<5.1; non-responders: change from baseline =< 0.6 or change from baseline >0.6 and =<1.2 with DAS28 >5.1. Percentage of participants with good response have been reported in the outcome measure.

The Disease Activity Score Based on 28-joints Count based EULAR response criteria were used to measure individual response as none, good, and moderate, depending on the extent of change from baseline and the level of disease activity reached. Good responders: change from baseline >1.2 with DAS28 =< 3.2; moderate responders: change from baseline >1.2 with DAS28 >3.2 to =<5.1 or change from baseline >0.6 to =<1.2 with DAS28 =<5.1; non-responders: change from baseline =< 0.6 or change from baseline >0.6 and =<1.2 with DAS28 >5.1. Percentage of participants with good or moderate response have been reported in this outcome measure.

The Disease Activity Score Based on 28-joints Count based EULAR response criteria were used to measure individual response as none, good, and moderate, depending on the extent of change from baseline and the level of disease activity reached. Good responders: change from baseline >1.2 with DAS28 =< 3.2; moderate responders: change from baseline >1.2 with DAS28 >3.2 to =<5.1 or change from baseline >0.6 to =<1.2 with DAS28 =<5.1; non-responders: change from baseline =< 0.6 or change from baseline >0.6 and =<1.2 with DAS28 >5.1. Percentage of participants with good or moderate response have been reported in this outcome measure.

SDAI score consisted of following parameters: TJC (28 joints), SJC (28 joints), SGA, PGA, CRP (mg/dL), and calculated according to description. SDAI = TJC + SJC + SGA + PGA + CRP. The SDAI score ranges from 0 to approximately 86. Higher SDAI indicates greater disease activity. SDAI Remission was defined as SDAI score ≤ 3.3.

SDAI score consisted of following parameters: TJC (28 joints), SJC (28 joints), SGA, PGA, CRP (mg/dL), and calculated according to description: SDAI = TJC + SJC + SGA + PGA + CRP. The SDAI score ranges from 0 to approximately 86. Higher SDAI indicates greater disease activity.

CDAI score consisted of following parameters: TJC (28 joints), SJC (28 joints), SGA (0-10 cm VAS), PGA (0-10 cm VAS), and calculated according to description: CDAI = TJC + SJC + SGA + PGA. The CDAI score ranges from 0 to approximately 76. CDAI. Remission was defined as CDAI score ≤ 2.8.

CDAI score consisted of following parameters: TJC (28 joints), SJC (28 joints), SGA (0-10 cm VAS), PGA (0-10 cm VAS), and calculated according to description: CDAI = TJC + SJC + SGA + PGA. The CDAI score ranges from 0 to approximately 76. Higher CDAI indicates greater disease activity.

FACIT-Fatigue was used to assess the burden of self-reported fatigue caused by a chronic disease and its impact upon daily activities and function. It has 13-items with symptom-specific questions, each of the 13 items of the FACIT-Fatigue scale ranges from 0 (Not at all) - 4 (Very much), the range of possible scores is 0 - 52. Higher scores indicate higher fatigue.

WPAI consisted of 6 questions (Q1=Employment status; Q2=Hours absent from work due to the rheumatoid arthritis; Q3=Hours absent from work due to other reasons; Q4=Hours actually worked; Q5=Impact of the rheumatoid arthritis on productivity while working; Q6=Impact of the rheumatoid arthritis on productivity while doing regular daily activities other than work). Higher WPAI scores indicated greater activity impairment. The scores were multiplied by 100 to express in percentages. Percent work time missed due to problem was calculated as Q2/(Q2+Q4). Negative values indicate improvement from baseline.

WPAI consisted of 6 questions (Q1=Employment status; Q2=Hours absent from work due to the rheumatoid arthritis; Q3=Hours absent from work due to other reasons; Q4=Hours actually worked; Q5=Impact of the rheumatoid arthritis on productivity while working; Q6=Impact of the rheumatoid arthritis on productivity while doing regular daily activities other than work). Higher WPAI scores indicated greater activity impairment. The scores were multiplied by 100 to express in percentages. Percent impairment while working due to problem was calculated as Q5/10. Negative values indicate improvement from baseline.

WPAI consisted of 6 questions (Q1=Employment status; Q2=Hours absent from work due to the rheumatoid arthritis; Q3=Hours absent from work due to other reasons; Q4=Hours actually worked; Q5=Impact of the rheumatoid arthritis on productivity while working; Q6=Impact of the rheumatoid arthritis on productivity while doing regular daily activities other than work). Higher WPAI scores indicated greater activity impairment. The scores were multiplied by 100 to express in percentages. Percent overall work impairment due to problem was calculated as Q2/(Q2+Q4)+[(1-(Q2/(Q2+Q4))x(Q5/10)]. Negative values indicate improvement from baseline.

WPAI consisted of 6 questions (Q1=Employment status; Q2=Hours absent from work due to the rheumatoid arthritis; Q3=Hours absent from work due to other reasons; Q4=Hours actually worked; Q5=Impact of the rheumatoid arthritis on productivity while working; Q6=Impact of the rheumatoid arthritis on productivity while doing regular daily activities other than work) and a 1-week recall period. Higher WPAI scores indicated greater activity impairment. The scores were multiplied by 100 to express in percentages. Percent activity impairment due to problem was calculated as Q6/10. Negative values indicate improvement from baseline.

Participant-reported assessment of ability to perform tasks in 8 categories of daily living activities: dress/groom; arise; eat; walk; reach; grip; hygiene; and common activities over past week. Each item was scored on 4-point scale from 0 to 3: 0=no difficulty; 1=some difficulty; 2=much difficulty; 3=unable to do. Overall score was computed as the sum of domain scores and divided by the number of domains answered. Total possible score range 0-3 where 0 = least difficulty and 3 = extreme difficulty.

Participant-reported assessment of ability to perform tasks in 8 categories of daily living activities: dress/groom; arise; eat; walk; reach; grip; hygiene; and common activities over past week. Each item was scored on 4-point scale from 0 to 3: 0=no difficulty; 1=some difficulty; 2=much difficulty; 3=unable to do. Overall score was computed as the sum of domain scores and divided by the number of domains answered. Total possible score range 0-3 where 0 = least difficulty and 3 = extreme difficulty.

Participant-reported assessment of ability to perform tasks in 8 categories of daily living activities: dress/groom; arise; eat; walk; reach; grip; hygiene; and common activities over past week. Each item was scored on 4-point scale from 0 to 3: 0=no difficulty; 1=some difficulty; 2=much difficulty; 3=unable to do. Overall score was computed as the sum of domain scores and divided by the number of domains answered. Total possible score range 0-3 where 0 = least difficulty and 3 = extreme difficulty.

Participants answered: "Considering all the ways your arthritis affects you, how are you feeling today?" Participants responded by using a 0 - 100 mm visual analog scale where 0 = very well and 100 = very poorly.

The participant assessed his/her own disease activity on a VAS of 0-100 mm on the questionnaire form. Higher SGA (100 mm VAS) scores indicate greater activity impairment.

The participant assessed his/her own pain severity on a visual analog scale (VAS) of 0-100 mm on the questionnaire form. Higher SGA of pain (100 mm VAS) scores indicated greater activity pain.

The SF-36v2 was scored for the 8 subscales (each range: 0-100 scale): 1. physical functioning, 2. role physical, 3. bodily pain, 4. general health, 5. vitality, 6. social functioning, 7. role-emotional, and 8. mental health. Physical Component Summary Score, Mental Component Summary Score and Role/Social Component Summary Score were calculated based on the 2007 General Japanese Population Means and Standard Deviations and coefficient. Component summary measures had means of 50 in 2007 General Japanese Population and deviation was expressed by the scale of 10. Higher score indicated better health state.

The SF-36v2 was scored for the 8 subscales (each range: 0-100 scale): 1. physical functioning, 2. role physical, 3. bodily pain, 4. general health, 5. vitality, 6. social functioning, 7. role-emotional, and 8. mental health. Physical Component Summary Score, Mental Component Summary Score and Role/Social Component Summary Score were calculated based on the 2007 General Japanese Population Means and Standard Deviations and coefficient. Component summary measures had means of 50 in 2007 General Japanese Population and deviation was expressed by the scale of 10. Higher score indicated better health state.

The SF-36v2 was scored for the 8 subscales (each range: 0-100 scale): 1. physical functioning, 2. role physical, 3. bodily pain, 4. general health, 5. vitality, 6. social functioning, 7. role-emotional, and 8. mental health. Physical Component Summary Score, Mental Component Summary Score and Role/Social Component Summary Score were calculated based on the 2007 General Japanese Population Means and Standard Deviations and coefficient. Component summary measures had means of 50 in 2007 General Japanese Population and deviation was expressed by the scale of 10. Higher score indicated better health state.

The SF-36v2 was scored for the 8 subscales (each range: 0-100 scale): 1. physical functioning, 2. role physical, 3. bodily pain, 4. general health, 5. vitality, 6. social functioning, 7. role-emotional, and 8. mental health. Physical Component Summary Score, Mental Component Summary Score and Role/Social Component Summary Score were calculated based on the 2007 General Japanese Population Means and Standard Deviations and coefficient. Component summary measures had means of 50 in 2007 General Japanese Population and deviation was expressed by the scale of 10. Higher score indicated better health state.

The SF-36v2 was scored for the 8 subscales (each range: 0-100 scale): 1. physical functioning, 2. role physical, 3. bodily pain, 4. general health, 5. vitality, 6. social functioning, 7. role-emotional, and 8. mental health. Physical Component Summary Score, Mental Component Summary Score and Role/Social Component Summary Score were calculated based on the 2007 General Japanese Population Means and Standard Deviations and coefficient. Component summary measures had means of 50 in 2007 General Japanese Population and deviation was expressed by the scale of 10. Higher score indicated better health state.

The SF-36v2 was scored for the 8 subscales (each range: 0-100 scale): 1. physical functioning, 2. role physical, 3. bodily pain, 4. general health, 5. vitality, 6. social functioning, 7. role-emotional, and 8. mental health. Physical Component Summary Score, Mental Component Summary Score and Role/Social Component Summary Score were calculated based on the 2007 General Japanese Population Means and Standard Deviations and coefficient. Component summary measures had means of 50 in 2007 General Japanese Population and deviation was expressed by the scale of 10. Higher score indicated better health state.

Participants who discontinued due to lack of efficacy have been reported.