Phase 2B Study of PTC124 (Ataluren) in Duchenne/Becker Muscular Dystrophy (DMD/BMD)

Change From Baseline in Time to Stand From Supine Position at Week 48

If the time taken to perform this test exceeded 30 seconds or if a participant could not perform this test due to disease progression, a value of 30 seconds was used. Change from baseline data has been reported.

Time frame: Baseline, Week 48

Change From Baseline in Time to Walk/Run 10 Meters at Week 48

If the time taken to perform this test exceeded 30 seconds or if a participant could not perform this test due to disease progression, a value of 30 seconds was used. Change from baseline data has been reported.

Time frame: Baseline, Week 48

Change From Baseline in Time to Climb 4 Stairs at Week 48

If the time taken to perform this test exceeded 30 seconds or if a participant could not perform this test due to disease progression, a value of 30 seconds was used. Change from baseline data has been reported.

Time frame: Baseline, Week 48

Change From Baseline in Time to Descend 4 Stairs at Week 48

If the time taken to perform this test exceeded 30 seconds or if a participant could not perform this test due to disease progression, a value of 30 seconds was used. Change from baseline data has been reported.

Time frame: Baseline, Week 48

Change From Baseline in Force Exerted During Knee Flexion and Extension, Elbow Flexion and Extension, and Shoulder Abduction at Week 48, as Assessed by Myometry

Upper and lower extremity myometry was performed using a myometer following standardized procedures. Muscle groups evaluated included knee flexors, knee extensors, elbow flexors, elbow extensors, and shoulder abductors. Bilateral assessments were done and 3 measurements were recorded from each muscle group on each side if possible. Mean values for the left and right sides were calculated.

Time frame: Baseline, Week 48

Change From Baseline in Mean Activity Period/Day/Visit at Week 48, as Assessed by Step Activity Monitoring (SAM)

The SAM is a pedometer (worn on the ankle) that continuously records the number of steps per time interval. Participants were instructed to continue to wear the SAM for at least 9 consecutive days. SAM was used to record the number of strides/minute following each visit. A stride is the leg motion that begins when the foot with SAM leaves the floor and ends when the same foot touches the floor again (that is, a stride generally equals 2 steps). Mean activity period/day/visit was computed for each participant. Mean obtained during Screening (Week -6 to -1) and following Week 1 visit were used as baseline data for analysis. For each day, an active period was defined as the first time after 3:00 AM that greater than (\>) 2 strides/minute were recorded to the last time prior to midnight that \>2 strides/minute were recorded. Days were deleted on which such an active period was less than (\<) 50 percent (%) of the mean active period across all days for that participant's visit.

Time frame: Baseline, Week 48

Change From Baseline in Mean Total Step Count/Day/Visit During the Active Periods at Week 48, as Assessed by SAM

The SAM is a pedometer (worn on the ankle) that continuously records the number of steps per time interval. Participants were instructed to continue to wear the SAM for at least 9 consecutive days. SAM was used to record the number of strides/minute following each visit. A stride is the leg motion that begins when the foot with SAM leaves the floor and ends when the same foot touches the floor again (that is, a stride generally equals 2 steps). Mean total step count/day/visit during the active periods was computed for each participant. Mean obtained during Screening (Week -6 to -1) and following Week 1 visit were used as baseline data for analysis. For each day, an active period was defined as the first time after 3:00 AM that \>2 strides/minute were recorded to the last time prior to midnight that \>2 strides/minute were recorded. Days were deleted on which such an active period was \<50% of the mean active period across all days for that participant's visit.

Time frame: Baseline, Week 48

Change From Baseline in Mean Total Step Count/Hour During the Active Period at Week 48, as Assessed by SAM

The SAM is a pedometer (worn on the ankle) that continuously records the number of steps per time interval. Participants were instructed to continue to wear the SAM for at least 9 consecutive days. SAM was used to record the number of strides/minute following each visit. A stride is the leg motion that begins when the foot with SAM leaves the floor and ends when the same foot touches the floor again (that is, a stride generally equals 2 steps). Mean total step count/hour during the active periods for the days in a visit was computed for each participant. Mean obtained during Screening (Week -6 to -1) and following Week 1 visit were used as baseline data for analysis. For each day, an active period was defined as the first time after 3:00 AM that \>2 strides/minute were recorded to the last time prior to midnight that \>2 strides/minute were recorded. Days were deleted on which such an active period was \<50% of the mean active period across all days for that participant's visit.

Time frame: Baseline, Week 48

Change From Baseline in Maximum Continuous 10-minute, 20-minute, 30-minute, and 60-minute Total Step Count at Week 48, as Assessed by SAM

SAM is a pedometer (worn on the ankle) that continuously records the number of steps per time interval. Participants were instructed to continue to wear the SAM for at least 9 consecutive days. SAM was used to record the number of strides/minute following each visit. A stride is the leg motion that begins when the foot with SAM leaves the floor and ends when the same foot touches the floor again (that is, a stride generally equals 2 steps). The maximum continuous 10-minute, 20-minute, 30-minute, and 60-minute total step counts were computed for each participant. Mean obtained during Screening (Week -6 to -1) and following Week 1 visit were used as baseline data for analysis. For each day, an active period was defined as the first time after 3:00 AM that \>2 strides/minute were recorded to the last time prior to midnight that \>2 strides/minute were recorded. Days were deleted on which such an active period was \<50% of the mean active period across all days for that participant's visit.

Time frame: Baseline, Week 48

Change From Baseline in Percentage of Time During the Active Period Spent at Low Activity (Less Than or Equal to [≤] 15 Steps/Minute), Medium Activity (16-30 Steps/Minute), and High Activity (Greater Than [>]30 Steps/Minute) at Week 48

SAM is a pedometer(worn on the ankle) that continuously records the number of steps per time interval. Participants were instructed to continue to wear the SAM for at least 9 consecutive days. SAM was used to record the number of strides/minute following each visit. A stride is the leg motion that begins when the foot with SAM leaves the floor and ends when the same foot touches the floor again. Proportion of time during active periods spent at low activity(≤15 steps/minute), medium activity(16-30 steps/minute), and high activity(\>30 steps/minute) were computed for each participant. Mean obtained during Screening and following Week 1 visit were used as baseline data for analysis. For each day, an active period was defined as first time after 3:00 AM that \>2 strides/minute were recorded to the last time prior to midnight that \>2 strides/minute were recorded. Days were deleted on which such an active period was \<50% of the mean active period across all days for that participant's visit.

Time frame: Baseline, Week 48

Change From Baseline in Participant- Reported Health-Related Quality of Life (HRQL) as Measured by the Pediatric Quality of Life Inventory (PedsQL) Physical, Emotional, Social, and School Functioning Domain Scores at Week 48

HRQL was measured via the PedsQL. The generic core module (including physical, emotional, social and school functioning scales) comprises 23 questions and the fatigue-specific module (including general fatigue, sleep/rest fatigue, and cognitive fatigue scales) comprises an additional 18 questions. The PedsQL was completed by both the participant and/or a parent/caregiver. Examples of items in each of the generic core module scales include: "It is hard for me to run"; "I feel sad or blue"; "I cannot do things that other kids my age can do;" and "It is hard to pay attention in class." Each of the generic core module items was scored on a 5-point likert response scale from 0 (never a problem) to 4 (almost always a problem). Scores were transformed on a scale from 0 to 100 (0=100, 1=75, 2=50, 3=25, 4=0), with higher scores indicating better health-related quality of life. Change from Baseline was calculated by subtracting the Baseline value from the value at Week 48.

Time frame: Baseline, Week 48

Change From Baseline in Parent/Caregiver- Reported HRQL as Measured by the PedsQL Physical, Emotional, Social, and School Functioning Domain Scores at Week 48

HRQL was measured via the PedsQL. The generic core module (including physical, emotional, social and school functioning scales) comprises 23 questions and the fatigue-specific module (including general fatigue, sleep/rest fatigue, and cognitive fatigue scales) comprises an additional 18 questions. The PedsQL was completed by both the participant and/or a parent/caregiver. Examples of items in each of the generic core module scales include: "It is hard for me to run"; "I feel sad or blue"; "I cannot do things that other kids my age can do;" and "It is hard to pay attention in class." Each of the generic core module items was scored on a 5-point likert response scale from 0 (never a problem) to 4 (almost always a problem). Scores were transformed on a scale from 0 to 100 (0=100, 1=75, 2=50, 3=25, 4=0), with higher scores indicating better health-related quality of life. Change from Baseline was calculated by subtracting the Baseline value from the value at Week 48.

Time frame: Baseline, Week 48

Change From Baseline in Participant-Reported HRQL as Measured by the Total Fatigue Scale Score at Week 48

HRQL was measured via the PedsQL. The fatigue-specific module (including general fatigue, sleep/rest fatigue, and cognitive fatigue scales) comprises an additional 18 questions. PedsQL was completed by both the participant and/or a parent/caregiver. Fatigue-specific module obtains information relating to items such as: "I feel too tired to do things that I like to do"; "I spend a lot of time in bed"; and "I have trouble remembering more than one thing at a time;" Each of the fatigue-specific module items was scored on a 5-point likert response scale from 0 (never a problem) to 4 (almost always a problem). Scores were transformed on a scale from 0 to 100 (0=100, 1=75, 2=50, 3=25, 4=0), with higher scores indicating less fatigue. Total score was the sum of all items over the number of items answered on all scales. Change from Baseline was calculated by subtracting the Baseline value from the value at Week 48.

Time frame: Baseline, Week 48

Change From Baseline in Parent/Caregiver-Reported HRQL as Measured by the Total Fatigue Scale Score at Week 48

HRQL was measured via the PedsQL. The fatigue-specific module (including general fatigue, sleep/rest fatigue, and cognitive fatigue scales) comprises an additional 18 questions. The PedsQL was completed by both the participant and/or a parent/caregiver. Fatigue-specific module obtains information relating to items such as: "I feel too tired to do things that I like to do"; "I spend a lot of time in bed"; and "I have trouble remembering more than one thing at a time;" Each of the fatigue-specific module items was scored on a 5-point likert response scale from 0 (never a problem) to 4 (almost always a problem). Scores were transformed on a scale from 0 to 100 (0=100, 1=75, 2=50, 3=25, 4=0), with higher scores indicating less fatigue. Total score was the sum of all items over the number of items answered on all scales. Change from Baseline was calculated by subtracting the Baseline value from the value at Week 48.

Time frame: Baseline, Week 48

Parent/Caregiver-Reported Treatment Satisfaction Questionnaire for Medication (TSQM) Score

TSQM consisted of 14 questions about treatment satisfaction with drug in 4 domains: Effectiveness (Questions 1-3 scored as 1 \[extremely dissatisfied\] to 7 \[extremely satisfied\]), Side Effects (question 4 scored as 0 \[no\] or 1 \[yes\]; question 5 scored as 1 \[extremely bothersome\] to 5 \[not at all bothersome\]; questions 6 - 8 scored as 1 \[a great deal\] to 5 \[not at all\]), Convenience (questions 9 and 10 scored as 1 \[extremely difficult\] to 7 \[extremely easy\]; question 11 scored as 1 \[extremely inconvenient\] to 5 \[extremely convenient\]) and Global Satisfaction (question 12 scored as 1 \[not at all confident\] to 7 \[extremely confident\]; question 13 scored as 1 \[not at all certain\] to 5 \[extremely certain\]; question 14 scored as 1 \[extremely dissatisfied\] to 5 \[extremely satisfied\]). The scores of each of the domains were added together and an algorithm was used to create a score of 0 to 100, with higher scores indicating better treatment satisfaction.

Time frame: Week 48

Change From Baseline in Participant/Caregiver-Reported Number of Daily Accidental Falls at Week 48

Number of falls was determined by daily diary records maintained by participants and/or parent/caregivers.

Time frame: Baseline, Week 48

Change From Baseline in Number of Digits Recalled Forwards and Backwards on Digit Span Task at Week 48

Basic attention and working memory was measured using the digit span task. A series of digits (0-9) were presented to the child in an auditory format only. The task had 2 parts; in the forward condition, the child was requested to repeat back the digits in the order they were presented and in the backward condition, he was requested to reverse the order of presentation. A raw score of the total number of correct responses was converted to an age-scaled-score (z-score) by subtracting the corresponding mean and dividing by the corresponding standard deviation of a reference population for that age.

Time frame: Baseline, Week 48

Change From Baseline in Heart Rate Before, During, and After Each 6MWT at Week 48, as Assessed by Heart Rate Monitoring With the Polar® RS400

The heart rate was measured with a Polar RS400 heart rate monitor, which consists of a transmitter strap worn around the chest and a wristwatch receiver. The monitor produces a digital text file with 1 value per minute that represents the mean heart rate for that minute. Mean heart rates values were collected prior to, during, and after the 6MWT. The participant rested for 5 minutes in a sitting position prior to the 6MWT, and the mean heart rate for the last minute of this rest period was collected and documented as the resting heart rate. During the 6MWT, the mean heart rate was collected and documented as the active heart rate. After completing the 6MWT and resting for 3 minutes, the mean heart rate for 1 minute was collected and documented as the recovery heart rate.

Time frame: Baseline, Week 48

Change From Baseline in Serum Concentration of Creatine Kinase (CK) at Week 48

Blood samples collected for chemistry assays were used to quantify serum CK concentrations. Serum CK was assessed as a potential biomarker for muscle fragility, with a reduction in serum CK considered to be a positive outcome.

Time frame: Baseline, Week 48

Percent Change From Pre-Treatment Visit (1 Week Prior to Baseline Visit) in Biceps Muscle Dystrophin Expression at Post-Treatment Visit (Week 36), as Determined by Immunofluorescence

Immunofluorescence evidence of a change in dystrophin expression on biceps muscle biopsy was defined as an increase in the staining of the sarcolemmal membrane with an antibody to the C-terminal portion of the dystrophin protein (excluding revertant fibers) between the pre-treatment (1 week prior to Baseline visit) and post-treatment (Week 36) biopsies. The biceps muscle was biopsied from one arm for confirmation of the absence or reduced levels of dystrophin prior to treatment initiation and from the other arm to assess for production of dystrophin post-treatment.

Time frame: Pre-Treatment (1 week prior to baseline), post-treatment (Week 36)