Efficacy, Safety and Pharmacokinetics of Teriflunomide in Pediatric Patients With Relapsing Forms of Multiple Sclerosis

Participant was considered free of clinical relapse if the participant had no confirmed clinical relapse before treatment discontinuation/completion in 192 weeks treatment period. Clinical relapses: new/recurrent neurological symptoms not associated with fever/infection, lasted at least 24 hours, and accompanied by new objective neurological findings upon neurological examination and documented by standardized, quantified FSSs which included 8 items: rated on different scales: brain stem, cerebellar and cerebral functions rated on scale of 0 to 5; visual, pyramidal, sensory and bowel/bladder rated on scale of 0 to 6 \& ambulation on scale of 0 to 12, where higher score in each scale indicated worsened neurological function. New/recurrent symptoms occurred less than 30 days following onset of relapse were considered part of same relapse. Probability of participants who were clinical relapse free at specified weeks were estimated by Kaplan-Meier method and reported.

Number of new or enlarged T2 lesions per scan was defined as the total number of new or enlarged T2 lesion that occurred during the 192 weeks treatment period divided by the total number of scans performed during 192 weeks. To account for the different numbers of scans performed among the participants, a negative binomial regression model with robust variance estimation was used. The model included the total number of new or enlarged T2-lesions as the response variable, with treatment group, region, pubertal status and age as covariates and log-transformed number of scans as an offset variable.

The number of T1 Gd-Enhancing lesions per scan was defined as the total number of Gd-enhancing lesions that occurred during the 192 weeks treatment period divided by the total number of scans performed during 192 weeks. To account for the different number of scans performed among the participants, a negative binomial regression model with robust variance estimation was used. The model included the total number of T1-lesions as the response variable, with treatment group, region, pubertal status and age as covariates and log-transformed number of scans as an offset variable.

Volume of T2 lesions was measured by MRI scan.

Volume of T1 hypointense lesions was measured by MRI scan.

The number of new T1 hypointense lesions were obtained from MRI scans.

Percentage of participants who were free of new or enlarged T2 lesions at Weeks 24, 48, 72, 96, 144 and 192 were reported.

Percent change from baseline in brain volume (assessed using MRI scans of the Brain) at Weeks 24, 36, 48,72, 96, 144 and 192 was reported.

SDMT measures the time to pair abstract symbols with specific numbers. It is a simple substitution task that gives the examinee 90 seconds to pair specific numbers with given geometric figures as a measure for screening cognitive impairment. The SDMT score is the number of correct substitution and ranged from 0 (worst outcome) to 110 (best outcome), where higher score indicated better cognitive function.

SDMT measures the time to pair abstract symbols with specific numbers. It is a simple substitution task that gives the examinee 90 seconds to pair specific numbers with given geometric figures as a measure for screening cognitive impairment. The SDMT score is the number of completed items and ranged from 0 (worst outcome) to 110 (best outcome), where higher score indicated better cognitive function.

The BVMT consists of three trials in which participants must recall shapes by drawing figures on a blank page (response booklet) after being given the opportunity to memorize the figures (given in BMVT-R form) for 10 seconds. BMVT-R form consists of six figures. Points are awarded based on the accuracy of the drawn figure and by correct placement on the blank page. A minimum of 0 to 12 points/scores are awarded per trial, so a participant can score between 0 and 36 points for all three trials (by adding the points/score from each trial), where higher score indicates better outcome.

'Trail Making Test Part A' is a neuropsychological test of visual attention and task switching. The task requires a participant to 'connect-the-dots' of 25 consecutive numbers (1,2, 3, etc.) in sequential order on a sheet of paper or computer screen. The goal of the participant is to finish the test as quickly as possible, and the time taken to complete the test used as the primary performance metric (in seconds). This is a timed test and the number of seconds to complete the task is recorded. Maximum time allowed is 300 seconds. A lower score indicated better cognitive function.

TMT-B is a cognitive test that gives a measure of various aspects of cognitive performance. It is used to measure cognitive fatigue. The test consisted of 25 circles containing 13 sequential numbers (1 to 13) and 12 sequential letters (A to L) positioned. The test evaluates the time (in seconds) to correctly order letters and numbers in alternate order (1, A, 2, B etc.). Maximum time allowed is 300 seconds, where less time/lower score indicated better cognitive function/performance.

The Beery VMI is a non-verbal assessment that assessed the extent to which individuals can integrate their visual and motor abilities. The participants were provided with geometric designs ranging from simple line drawings to more complex figures and were asked to copy the designs. The test consisted of 24 figures. One point was scored for each successful copy of drawings and no scoring was given when the participant failed to copy the drawings properly. Each successful copying of drawings was summed up and the total was scored on a scale ranged from 0 to 24, where higher score indicated better visual construction skills/better visual and motor abilities and lower score indicated poor visual construction skills/poor visual and motor abilities.

The WASI-II: Vocabulary test is a quick estimate of an individual's level of intellectual functioning which comprised of 31 total items that required the participant to orally define 3 images and 28 words presented both orally and visually. Items 1 to 3 rated on a score of 0 or 1, items 4 and 5 rated on a score of 0 or 2, items 6 to 31 rated on a scale of 0 to 2. Each item score was summed up to derive the total score which ranged from 0 (minimum score) to 59 (maximum score), where higher score indicated better level of intellectual functioning/higher level of intelligence.

Letter Fluency is a condition measured in the D-KEFS. Participants were asked to name as many words as they can, starting with a specified letter for 60 seconds. The words cannot be names, places, numbers or grammatical variants of previous answers. Repeated answers were not scored as a correct response. There were 3 trials, with 3 different letters. The total number of correct responses was totaled for all 3 trials and a letter fluency score was given. A higher score was considered better. There was no set range as the score depends on how many correct words the participant relays in the given time period.

Category Fluency is a condition measured in the D-KEFS. It measured participant's ability to generate words from three different categories (e.g., fruits, vegetables and animals), within a minute for each category. Total score was number of correct words for each category with no points for repetitions or non-words. Score ranged from 0 to unlimited, where 0 = low score, higher score indicated better performance.

SRT is a test to assess verbal learning and memory. During the administration of the SRT only the examiner and the participant should be in the testing room. A list of twelve words was read aloud by the examiner at a rate of one word per two seconds. The participant is asked to recall all twelve words after a 30 minute delay. Only the words that were missed on the preceding trial were given in the consecutive trial. The total score represented a sum score of total 6 trials, therefore the score range was from 0 to 72. The lower the score the worse the outcome, higher score indicated better recall.

Ctrough was defined as the concentration reached by the drug before the next dose administered. Data for this outcome measure was planned to be collected and analyzed separately for each dose of Teriflunomide. PK samples for teriflunomide 3.5 mg were collected during the first 8 weeks but all participants were switched to teriflunomide 7 mg after Week 8. Hence, plasma concentration of teriflunomide 7 mg and 14 mg were reported.

Time to first clinical relapse was defined as duration (in weeks) after enrollment in OL period and first confirmed clinical relapse. Clinical relapses were defined as new or recurrent neurological symptoms not associated with fever or infection, lasted at least 24 hours and accompanied by new objective neurological findings upon neurological examination and documented by standardized, quantified FSSs which included 8 items and items were rated on different scales: brain stem, cerebellar \& cerebral functions rated on scale of 0 to 5; visual, pyramidal, sensory and bowel/bladder rated on scale of 0 to 6 and ambulation on scale of 0 to 12 where higher score in each scale indicated worsened neurological function. Confirmed clinical relapse were reviewed and confirmed by independent RAP. Participant without confirmed clinical relapse, was considered as clinical relapse free until end of Week 192.

Ctrough was defined as the concentration reached by the drug before the next dose is administered. Data for this outcome measure was planned to be collected and analyzed separately for each dose of teriflunomide. PK samples for teriflunomide 3.5 mg were collected during the first 8 weeks but all participants were switched to teriflunomide 7 mg after Week 8. Hence, plasma concentration of teriflunomide 7 mg and 14 mg were reported.