Model-Informed Precision Dosing Guidance of Ethosuximide Developed from a Randomized Controlled Clinical Trial of Childhood Absence Epilepsy.

Ethosuximide was identified as the optimal option for new-onset childhood absence epilepsy (CAE) in a randomized, two-phase dose escalation comparative effectiveness trial of ethosuximide, lamotrigine, and valproic acid. However, 47% of ethosuximide initial monotherapy participants experienced short-term treatment failure. This study aimed to characterize the initial monotherapy ethosuximide exposure-response relationship and to propose model-informed precision dosing guidance. Dose titration occurred over a 16-20-week period until patients experienced seizure freedom or intolerable side effects. Subjects with initial monotherapy failure were randomized to one of the other two medications and dose escalation was repeated. A population pharmacokinetic model was created using plasma concentration data (n = 1,320), collected at 4-week intervals from 211 unique participants during both the initial and second monotherapy phases. A logistic regression analysis was performed on the initial monotherapy cohort (n = 103) with complete exposure-response data. Eighty-four participants achieved seizure freedom with a wide range of ethosuximide area under the curves (AUC) ranging from 420 to 2,420 µg·h/mL. AUC exposure estimates for achieving a 50% and 75% probability of seizure freedom were 1,027 and 1,489 µg·h/mL, respectively, whereas the corresponding cumulative frequency of intolerable adverse events was 11% and 16%. Monte Carlo Simulation indicated a daily dose of 40 and 55 mg/kg to achieve 50% and 75% probability of seizure freedom in the overall population, respectively. We identified the need for adjusted mg/kg dosing in different body weight cohorts. This ethosuximide proposed model-informed precision dosing guidance to achieve seizure freedom carries promise to optimize initial monotherapy success for patients with CAE.

The CINRG Becker Natural History Study: Baseline characteristics.

We performed an observational, natural history study of males with in-frame dystrophin gene deletions causing Becker muscular dystrophy (BMD). A prospective natural history study collected longitudinal medical, strength, and timed function assessments. Eighty-three participants with genetically confirmed BMD were enrolled (age range 5.6-75.4 years). Lower extremity function and the percentage of participants who retained ambulation declined across the age span. The largest single group of participants had in-frame deletions that corresponded to an out-of-frame deletion treated with an exon 45 skip to restore the reading frame. This group of 54 participants showed similarities in baseline motor functional assessments when compared to the group of all others in the study. A prospective natural history cohort with in-frame dystrophin gene deletions offers the potential to contribute to clinical trial readiness for BMD and to analyze therapeutic benefit of exon skipping for Duchenne muscular dystrophy.

Differential antiseizure medication sensitivity of the Affective Reactivity Index: A randomized controlled trial in new-onset pediatric focal epilepsy.

BACKGROUND: Irritability is a adverse effect of many antiseizure medications (ASMs), but there are no validated measures currently available to characterize this behavioral risk. We examined both child and parent/guardian versions of the Affective Reactivity Index (ARI), a validated measure developed for application in adolescent psychiatry, to determine its sensitivity to ASM-related irritability. We hypothesized irritability increases associated with levetiracetam (LEV) but not lamotrigine (LTG) or oxcarbazepine (OXC). METHOD: The ARI was administered to 71 child and parent/guardian pairs randomized to one of three common ASMs (LEV, LTG, OXC) used to treat new-onset focal (localization-related) epilepsy. Subjects were recruited as part of a prospective multicenter, randomized, open-label, parallel group design. The ARI was administered at baseline prior to treatment initiation and again at 3 months after ASM initiation. RESULTS: There was a significant increase in ARI ratings for both child and parent/guardian ratings for LEV but not LTG or OXC when assessed 3 months after treatment initiation. When examined on the individual subject level using a criterion of at least a 3-point ARI increase, there was an increase associated with LEV for child ratings but not parent/guardian scores. CONCLUSION: Both child and parent/guardian versions of the ARI appear sensitive to medication-induced irritability associated with LEV on both the group and individual levels. The findings extend the applicability of ARI from characterizing the presence of clinical irritability as a psychiatric diagnostic feature to a more modifiable aspect of behavior change related to medication management and support its use in clinical trial applications.

Vamorolone trial in Duchenne muscular dystrophy shows dose-related improvement of muscle function.

OBJECTIVE: To study vamorolone, a first-in-class steroidal anti-inflammatory drug, in Duchenne muscular dystrophy (DMD). METHODS: An open-label, multiple-ascending-dose study of vamorolone was conducted in 48 boys with DMD (age 4-<7 years, steroid-naive). Dose levels were 0.25, 0.75, 2.0, and 6.0 mg/kg/d in an oral suspension formulation (12 boys per dose level; one-third to 10 times the glucocorticoid dose in DMD). The primary goal was to define optimal doses of vamorolone. The primary outcome for clinical efficacy was time to stand from supine velocity. RESULTS: Oral administration of vamorolone at all doses tested was safe and well tolerated over the 24-week treatment period. The 2.0-mg/kg/d dose group met the primary efficacy outcome of improved muscle function (time to stand; 24 weeks of vamorolone treatment vs natural history controls), without evidence of most adverse effects of glucocorticoids. A biomarker of bone formation, osteocalcin, increased in vamorolone-treated boys, suggesting possible loss of bone morbidities seen with glucocorticoids. Biomarker outcomes for adrenal suppression and insulin resistance were also lower in vamorolone-treated patients with DMD relative to published studies of glucocorticoid therapy. CONCLUSIONS: Daily vamorolone treatment suggested efficacy at doses of 2.0 and 6.0 mg/kg/d in an exploratory 24-week open-label study. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for boys with DMD, vamorolone demonstrated possible efficacy compared to a natural history cohort of glucocorticoid-naive patients and appeared to be tolerated.

Assessment of disease progression in dysferlinopathy: A 1-year cohort study.

OBJECTIVE: To assess the ability of functional measures to detect disease progression in dysferlinopathy over 6 months and 1 year. METHODS: One hundred ninety-three patients with dysferlinopathy were recruited to the Jain Foundation's International Clinical Outcome Study for Dysferlinopathy. Baseline, 6-month, and 1-year assessments included adapted North Star Ambulatory Assessment (a-NSAA), Motor Function Measure (MFM-20), timed function tests, 6-minute walk test (6MWT), Brooke scale, Jebsen test, manual muscle testing, and hand-held dynamometry. Patients also completed the ACTIVLIM questionnaire. Change in each measure over 6 months and 1 year was calculated and compared between disease severity (ambulant [mild, moderate, or severe based on a-NSAA score] or nonambulant [unable to complete a 10-meter walk]) and clinical diagnosis. RESULTS: The functional a-NSAA test was the most sensitive to deterioration for ambulant patients overall. The a-NSAA score was the most sensitive test in the mild and moderate groups, while the 6MWT was most sensitive in the severe group. The 10-meter walk test was the only test showing significant change across all ambulant severity groups. In nonambulant patients, the MFM domain 3, wrist flexion strength, and pinch grip were most sensitive. Progression rates did not differ by clinical diagnosis. Power calculations determined that 46 moderately affected patients are required to determine clinical effectiveness for a hypothetical 1-year clinical trial based on the a-NSAA as a clinical endpoint. CONCLUSION: Certain functional outcome measures can detect changes over 6 months and 1 year in dysferlinopathy and potentially be useful in monitoring progression in clinical trials. CLINICALTRIALSGOV IDENTIFIER: NCT01676077.

Longitudinal pulmonary function testing outcome measures in Duchenne muscular dystrophy: Long-term natural history with and without glucocorticoids.

We describe changes in pulmonary function measures across time in Duchenne muscular dystrophy patients treated with glucocorticoids (GCs) > 1 year compared to GC naïve patients in the Cooperative International Research Group Duchenne Natural History Study, a multicenter prospective cohort study. 397 participants underwent 2799 pulmonary function assessments over a period up to 10 years. Fifty-three GC naïve participants (< 1 month exposure) were compared to 322 subjects with > 1 year cumulative GC treatment. Forced vital capacity (FVC), peak expiratory flow rate (PEFr), maximal inspiratory and expiratory pressures were performed and calculated as a percent predicted (%p). GC treatment slowed the rate of pulmonary decline as measured by FVC%p, in patients aged 7-9.9 years. GC treatment slowed 12 and 24-month progression of percent predicted spirometry to a greater degree in those with baseline FVC%p from < 80-34%. GC treatment resulted in higher peak absolute FVC and PEFr values with later onset of decline. Progression to an absolute FVC < 1 liter was delayed by GC treatment. Patients who reached a FVC below 1 L were 4.1 times more likely to die (p = 0.017). Long-term glucocorticoid treatment slows pulmonary disease progression in Duchenne dystrophy throughout the lifespan.

Maternal and child patterns of Medicaid retention: a prospective cohort study.

BACKGROUND: We sought to determine whether maternal Medicaid retention influences child Medicaid retention because caregivers play a critical role in assuring children's health access. METHODS: We conducted a longitudinal prospective cohort study of a convenience sample of 604 Medicaid-eligible mother-child dyads followed from the infant's birth through 24 months of age with parent surveys. Individual enrollment status was abstracted from administrative Medicaid eligibility files. Generalized estimating equations quantified the effect of maternal Medicaid enrollment status on child Medicaid retention, adjusting for relevant covariates. Because varying lengths of gaps may have different effects on child health outcomes, Medicaid enrollment status was further categorized by length of gap: any gap, > 14-days, and > 60-days. RESULTS: This cohort consists primarily of African-American (94%), unmarried mothers (88%), with a mean age of 23.2 years. In multivariable analysis, children whose mothers experienced any gaps in coverage had 12.6 times greater odds of experiencing gaps when compared to children whose mothers were continuously enrolled. Use of varying thresholds to define coverage gaps resulted in similar odds ratios (> 14-day gap = 11.8, > 60-day gap = 16.8). Cash assistance receipt and maternal knowledge of differences between Temporary Assistance to Needy Families and Medicaid eligibility criteria demonstrated strong protective effects against child Medicaid disenrollment. CONCLUSIONS: Medicaid disenrollment remains a significant policy problem and maternal Medicaid retention patterns show strong effects on child Medicaid retention. Policymakers need to invest in effective outreach strategies, including family-friendly application processes, to reduce enrollment barriers so that all eligible families can take advantage of these coverage opportunities.

A multinational study on motor function in early-onset FSHD.

OBJECTIVES: To investigate motor function associations with age, sex, and D4Z4 repeats among participants with early-onset facioscapulohumeral muscular dystrophy (FSHD) type 1 as defined by weakness onset before 10 years of age. METHODS: We collected standardized motor assessments, including manual muscle testing (MMT), quantitative muscle testing, functional motor evaluations, and clinical severity scores (CSSs), at 12 Cooperative International Neuromuscular Research Group centers. To measure associations, we used linear regression models adjusted for sex, evaluation age, age at onset of weakness, and D4Z4 repeats. RESULTS: Among 52 participants (60% female, mean age 22.9 ± 14.7 years), weakness was most pronounced in the shoulder and abdominal musculature. Older enrollment age was associated with greater CSSs (p = 0.003). When adjusted for enrollment age, sex, and D4Z4 repeats, younger age at onset of facial weakness was associated with greater CSSs, slower velocities in timed function tests, and lower MMT scores (p < 0.05). CONCLUSION: Significant clinical variability was observed in early-onset FSHD. Earlier age at onset of facial weakness was associated with greater disease severity. Longitudinal assessments are needed to determine the rate of disease progression in this population.

Conducting an investigator-initiated randomized double-blinded intervention trial in acute decompensation of inborn errors of metabolism: Lessons from the N-Carbamylglutamate Consortium.

Organic acidemias and urea cycle disorders are ultra-rare inborn errors of metabolism characterized by episodic acute decompensation, often associated with hyperammonemia, resulting in brain edema and encephalopathy. Retrospective reports and translational studies suggest that N-carbamylglutamate (NCG) may be effective in reducing ammonia levels during acute decompensation in two organic acidemias, propionic and methylmalonic acidemia (PA and MMA), and in two urea cycle disorders, carbamylphosphate synthetase 1 and ornithine transcarbamylase deficiency (CPSD and OTCD). We established the 9-site N-carbamylglutamate Consortium (NCGC) in order to conduct two randomized double-blind, placebo-controlled trials of NCG in acute hyperammonemia of PA, MMA, CPSD and OTCD. Conducting clinical trials is challenging in any disease, but poses unique barriers and risks in the ultra-rare disorders. As the number of clinical trials in orphan diseases increases, evaluating the successes and opportunities for improvement in such trials is essential. We summarize herein the design, methods, experiences, challenges and lessons from the NCGC-conducted trials.

Long-term effects of glucocorticoids on function, quality of life, and survival in patients with Duchenne muscular dystrophy: a prospective cohort study.

BACKGROUND: Glucocorticoid treatment is recommended as a standard of care in Duchenne muscular dystrophy; however, few studies have assessed the long-term benefits of this treatment. We examined the long-term effects of glucocorticoids on milestone-related disease progression across the lifespan and survival in patients with Duchenne muscular dystrophy. METHODS: For this prospective cohort study, we enrolled male patients aged 2-28 years with Duchenne muscular dystrophy at 20 centres in nine countries. Patients were followed up for 10 years. We compared no glucocorticoid treatment or cumulative treatment duration of less than 1 month versus treatment of 1 year or longer with regard to progression of nine disease-related and clinically meaningful mobility and upper limb milestones. We used Kaplan-Meier analyses to compare glucocorticoid treatment groups for time to stand from supine of 5 s or longer and 10 s or longer, and loss of stand from supine, four-stair climb, ambulation, full overhead reach, hand-to-mouth function, and hand function. Risk of death was also assessed. This study is registered with ClinicalTrials.gov, number NCT00468832. FINDINGS: 440 patients were enrolled during two recruitment periods (2006-09 and 2012-16). Time to all disease progression milestone events was significantly longer in patients treated with glucocorticoids for 1 year or longer than in patients treated for less than 1 month or never treated (log-rank p<0·0001). Glucocorticoid treatment for 1 year or longer was associated with increased median age at loss of mobility milestones by 2·1-4·4 years and upper limb milestones by 2·8-8·0 years compared with treatment for less than 1 month. Deflazacort was associated with increased median age at loss of three milestones by 2·1-2·7 years in comparison with prednisone or prednisolone (log-rank p<0·012). 45 patients died during the 10-year follow-up. 39 (87%) of these deaths were attributable to Duchenne-related causes in patients with known duration of glucocorticoids usage. 28 (9%) deaths occurred in 311 patients treated with glucocorticoids for 1 year or longer compared with 11 (19%) deaths in 58 patients with no history of glucocorticoid use (odds ratio 0·47, 95% CI 0·22-1·00; p=0·0501). INTERPRETATION: In patients with Duchenne muscular dystrophy, glucocorticoid treatment is associated with reduced risk of losing clinically meaningful mobility and upper limb disease progression milestones across the lifespan as well as reduced risk of death. FUNDING: US Department of Education/National Institute on Disability and Rehabilitation Research; US Department of Defense; National Institutes of Health/National Institute of Arthritis and Musculoskeletal and Skin Diseases; and Parent Project Muscular Dystrophy.

Pretreatment behavior and subsequent medication effects in childhood absence epilepsy.

OBJECTIVE: To characterize pretreatment behavioral problems and differential effects of initial therapy in children with childhood absence epilepsy (CAE). METHODS: The Child Behavior Checklist (CBCL) was administered at baseline, week 16-20, and month 12 visits of a randomized double-blind trial of ethosuximide, lamotrigine, and valproate. Total problems score was the primary outcome measure. RESULTS: A total of 382 participants at baseline, 310 participants at the week 16-20 visit, and 168 participants at the month 12 visit had CBCL data. At baseline, 8% (95% confidence interval [CI] 6%-11%) of children with CAE had elevated total problems scores (mean 52.9 ± 10.91). At week 16-20, participants taking valproic acid had significantly higher total problems (51.7 [98.3% CI 48.6-54.7]), externalizing problems (51.4 [98.3% CI 48.5-54.3]), attention problems (57.8 [98.3% CI 55.6-60.0]), and attention-deficit/hyperactivity problems (55.8 [98.3% CI 54.1-57.6]) scores compared to participants taking ethosuximide (46.5 [98.3% CI 43.4-49.6]; 45.8 [98.3% CI 42.9-48.7]; 54.6 [98.3% CI 52.4-56.9]; 53.0 [98.3% CI 51.3-54.8]). Lack of seizure freedom and elevated week 16-20 Conner Continuous Performance Test confidence index were associated with worse total problems scores. At month 12, participants taking valproic acid had significantly higher attention problems scores (57.9 [98.3% CI 55.6-60.3]) compared to participants taking ethosuximide (54.5 [95% CI 52.1-56.9]). CONCLUSIONS: Pretreatment and ongoing behavioral problems exist in CAE. Valproic acid is associated with worse behavioral outcomes than ethosuximide or lamotrigine, further reinforcing ethosuximide as the preferred initial therapy for CAE. CLINICALTRIALSGOV IDENTIFIER: NCT00088452. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for children with CAE, valproic acid is associated with worse behavioral outcomes than ethosuximide or lamotrigine.

Pretreatment seizure semiology in childhood absence epilepsy.

OBJECTIVE: To determine seizure semiology in children with newly diagnosed childhood absence epilepsy and to evaluate associations with short-term treatment outcomes. METHODS: For participants enrolled in a multicenter, randomized, double-blind, comparative-effectiveness trial, semiologic features of pretreatment seizures were analyzed as predictors of treatment outcome at the week 16 to 20 visit. RESULTS: Video of 1,932 electrographic absence seizures from 416 participants was evaluated. Median seizure duration was 10.2 seconds; median time between electrographic seizure onset and clinical manifestation onset was 1.5 seconds. For individual seizures and by participant, the most common semiology features were pause/stare (seizure 95.5%, participant 99.3%), motor automatisms (60.6%, 86.1%), and eye involvement (54.9%, 76.5%). The interrater agreement for motor automatisms and eye involvement was good (72%-84%). Variability of semiology features between seizures even within participants was high. Clustering analyses revealed 4 patterns (involving the presence/absence of eye involvement and motor automatisms superimposed on the nearly ubiquitous pause/stare). Most participants experienced more than one seizure cluster pattern. No individual semiologic feature was individually predictive of short-term outcome. Seizure freedom was half as likely in participants with one or more seizure having the pattern of eye involvement without motor automatisms than in participants without this pattern. CONCLUSIONS: Almost all absence seizures are characterized by a pause in activity or staring, but rarely is this the only feature. Semiologic features tend to cluster, resulting in identifiable absence seizure subtypes with significant intraparticipant seizure phenomenologic heterogeneity. One seizure subtype, pause/stare and eye involvement but no motor automatisms, is specifically associated with a worse treatment outcome.

Do changes in socio-demographic characteristics impact up-to-date immunization status between 3 and 24 months of age? A prospective study among an inner-city birth cohort in the United States.

INTRODUCTION: Low-income child populations remain under-vaccinated. Our objective was to determine differences in the relative importance of maternal health literacy and socio-demographic characteristics that often change during early childhood on up-to-date (UTD) immunization status among a low-income population. METHODS: We performed secondary data analysis of a longitudinal prospective cohort study of 744 Medicaid-eligible mother-infant dyads recruited at the time of the infant's birth from an inner-city hospital in the United States and surveyed every 6 months for 24 months. Our primary outcome was infant UTD status at 24 months abstracted from a citywide registry. We assessed maternal health literacy with the Test of Functional Health Literacy in Adults (short version). We collected socio-demographic information via surveys at birth and every 6 months. We compared predictors of UTD status at 3, 7, and 24 months. RESULTS: The cohort consisted of primarily African-American (81.5%) mothers with adequate health literacy (73.9%). Immunizations were UTD among 56.7% of infants at 24 months of age. Maternal health literacy was not a significant predictor of UTD immunization status. Instead, adjusted results showed that significant predictors of not-UTD status at 24 months were lack of a consistent health care location or "medical home" (OR 0.17, 95%CI 0.18-0.37), inadequate prenatal care (OR 0.48, 95%CI 0.25-0.95), and prior not-UTD status (OR 0.31, 95%CI 0.20-0.47). Notably, all upper confidence limits are less than 1.0 for these variables. Health care location type (e.g., hospital-affiliate, community-based, none) was a significant predictor of vaccine status at age 3 months, 7 months, and 24 months. CONCLUSIONS: Investing in efforts to support early establishment of a medical home to obtain comprehensive coordinated preventive care, including providing recommended vaccines on schedule, is a prudent strategy to improve vaccination status at the population level.

Pharmacogenetics of antiepileptic drug efficacy in childhood absence epilepsy.

OBJECTIVE: To determine whether common polymorphisms in CACNA1G, CACNA1H, CACNA1I, and ABCB1 are associated with differential short-term seizure outcome in childhood absence epilepsy (CAE). METHODS: Four hundred forty-six CAE children in a randomized double-blind trial of ethosuximide, lamotrigine, and valproate had short-term seizure outcome determined. Associations between polymorphisms (minor allele frequency ≥ 15%) in 4 genes and seizure outcomes were assessed. In vitro electrophysiology on transfected CACNA1H channels determined impact of 1 variant on T-type calcium channel responsiveness to ethosuximide. RESULTS: Eighty percent (357 of 446) of subjects had informative short-term seizure status (242 seizure free, 115 not seizure free). In ethosuximide subjects, 2 polymorphisms (CACNA1H rs61734410/P640L, CACNA1I rs3747178) appeared more commonly among not-seizure-free participants (p = 0.011, odds ratio [OR] = 2.63, 95% confidence limits [CL] = 1.25-5.56; p = 0.026, OR = 2.38, 95% CL = 1.11-5.00). In lamotrigine subjects, 1 ABCB1 missense polymorphism (rs2032582/S893A; p = 0.015, OR = 2.22, 95% CL = 1.16-4.17) was more common in not-seizure-free participants, and 2 CACNA1H polymorphisms (rs2753326, rs2753325) were more common in seizure-free participants (p = 0.038, OR = 0.52, 95% CL = 0.28-0.96). In valproate subjects, no common polymorphisms were associated with seizure status. In vitro electrophysiological studies showed no effect of the P640L polymorphism on channel physiology in the absence of ethosuximide. Ethosuximide's effect on rate of decay of CaV 3.2 was significantly less for P640L channel compared to wild-type channel. INTERPRETATION: Four T-type calcium channel variants and 1 ABCB1 transporter variant were associated with differential drug response in CAE. The in vivo P640L variant's ethosuximide effect was confirmed by in vitro electrophysiological studies. This suggests that genetic variation plays a role in differential CAE drug response. Ann Neurol 2017;81:444-453.

Second monotherapy in childhood absence epilepsy.

OBJECTIVE: To determine optimal second monotherapy for children with childhood absence epilepsy (CAE) experiencing initial treatment failure. METHODS: Children with CAE experiencing treatment failure during the double-blind phase of a randomized controlled trial comparing ethosuximide, valproic acid, and lamotrigine were randomized to open-label second monotherapy with one of the 2 other study therapies. Primary study outcome was freedom from failure proportion at week 16-20 and month 12 visits after randomization. Secondary study outcome was percentage of participants experiencing attentional dysfunction at these visits. RESULTS: A total of 208 children were enrolled, randomized, and received second therapy. At both week 16-20 visit and month 12 visit, ethosuximide's (63%, 57%) and valproic acid's (65%, 49%) freedom from failure proportions were similar to each other and higher than lamotrigine's (45%, 36%, p = 0.051 and p = 0.062). At both time points, ethosuximide and valproic acid had superior seizure control compared to lamotrigine (p < 0.0001). At both the week 16-20 and month 12 visits, attentional dysfunction was numerically more common with valproic acid than with ethosuximide or lamotrigine. For each medication, second monotherapy freedom from failure proportions demonstrated noninferiority to initial monotherapy freedom from failure proportions. CONCLUSIONS: As second monotherapy, ethosuximide and valproic acid, demonstrated higher freedom from failure proportions and greater efficacy than lamotrigine; valproic acid was associated with more attentional dysfunction. Ethosuximide is the optimal second monotherapy for children with CAE not responding to initial therapy with other medications. CLINICALTRIALSGOV IDENTIFIER: NCT00088452. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that for children with CAE experiencing initial treatment failure, second monotherapy with ethosuximide or valproic acid is superior to lamotrigine.

The Clinical Outcome Study for dysferlinopathy: An international multicenter study.

OBJECTIVE: To describe the baseline clinical and functional characteristics of an international cohort of 193 patients with dysferlinopathy. METHODS: The Clinical Outcome Study for dysferlinopathy (COS) is an international multicenter study of this disease, evaluating patients with genetically confirmed dysferlinopathy over 3 years. We present a cross-sectional analysis of 193 patients derived from their baseline clinical and functional assessments. RESULTS: There is a high degree of variability in disease onset, pattern of weakness, and rate of progression. No factor, such as mutation class, protein expression, or age at onset, accounted for this variability. Among patients with clinical diagnoses of Miyoshi myopathy or limb-girdle muscular dystrophy, clinical presentation and examination was not strikingly different. Respiratory impairment and cardiac dysfunction were observed in a minority of patients. A substantial delay in diagnosis was previously common but has been steadily reducing, suggesting increasing awareness of dysferlinopathies. CONCLUSIONS: These findings highlight crucial issues to be addressed for both optimizing clinical care and planning therapeutic trials in dysferlinopathy. This ongoing longitudinal study will provide an opportunity to further understand patterns and variability in disease progression and form the basis for trial design.

Obesity and overweight as CAE comorbidities and differential drug response modifiers.

OBJECTIVE: This study examined whether overweight and obesity are pretreatment comorbidities and predictors of short-term drug response in newly diagnosed untreated childhood absence epilepsy (CAE). We also examined whether dietary intake accounts for observed pretreatment body mass index (BMI) distribution. METHODS: Pretreatment height and weight were available for 445 of 446 participants in the NIH-funded CAE comparative effectiveness trial (NCT00088452). Twenty-four-hour dietary recalls were collected. Calculated BMI and dietary intake were standardized for age, sex, and race/ethnicity and compared to age-matched US population from the National Health and Nutrition Examination Survey (NHANES). Logistic regression models tested BMI as a predictor of treatment response. Pharmacokinetic variables were explored as contributors to differential drug response. RESULTS: After standardizing for demographic differences, children with CAE were more likely to be overweight (19.3% vs 13.8%; p < 0.001) or obese (14.5% vs 11.5%; p < 0.001) than NHANES controls. The combined prevalence of overweight and obesity was 33.8% in the CAE cohort and 25.3% among controls (p < 0.001). Mean daily energy intake (difference -79.5 kcal/day, p = 0.04) and daily carbohydrate intake (difference -10.7 g/day, p = 0.04) were lower in the CAE group than in NHANES controls. With increasing baseline BMI z score, the efficacy and effectiveness of ethosuximide and valproic acid over lamotrigine became more pronounced, despite no significant differences in drug exposure and trough levels. CONCLUSIONS: Overweight and obesity are more prevalent in children with newly diagnosed CAE than in age-matched peers, despite lower caloric and carbohydrate intake. Baseline BMI may also predict differential drug response, which cannot be attributed to pharmacokinetic differences.

Prednisone/prednisolone and deflazacort regimens in the CINRG Duchenne Natural History Study.

OBJECTIVE: We aimed to perform an observational study of age at loss of independent ambulation (LoA) and side-effect profiles associated with different glucocorticoid corticosteroid (GC) regimens in Duchenne muscular dystrophy (DMD). METHODS: We studied 340 participants in the Cooperative International Neuromuscular Research Group Duchenne Natural History Study (CINRG-DNHS). LoA was defined as continuous wheelchair use. Effects of prednisone or prednisolone (PRED)/deflazacort (DFZ), administration frequency, and dose were analyzed by time-varying Cox regression. Side-effect frequencies were compared using χ(2) test. RESULTS: Participants treated ≥1 year while ambulatory (n = 252/340) showed a 3-year median delay in LoA (p < 0.001). Fourteen different regimens were observed. Nondaily treatment was common for PRED (37%) and rare for DFZ (3%). DFZ was associated with later LoA than PRED (hazard ratio 0.294 ± 0.053 vs 0.490 ± 0.08, p = 0.003; 2-year difference in median LoA with daily administration, p < 0.001). Average dose was lower for daily PRED (0.56 mg/kg/d, 75% of recommended) than daily DFZ (0.75 mg/kg/d, 83% of recommended, p < 0.001). DFZ showed higher frequencies of growth delay (p < 0.001), cushingoid appearance (p = 0.002), and cataracts (p < 0.001), but not weight gain. CONCLUSIONS: Use of DFZ was associated with later LoA and increased frequency of side effects. Differences in standards of care and dosing complicate interpretation of this finding, but stratification by PRED/DFZ might be considered in clinical trials. This study emphasizes the necessity of a randomized, blinded trial of GC regimens in DMD. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that GCs are effective in delaying LoA in patients with DMD.

Long-term outcomes of generalized tonic-clonic seizures in a childhood absence epilepsy trial.

OBJECTIVE: To determine incidence and early predictors of generalized tonic-clonic seizures (GTCs) in children with childhood absence epilepsy (CAE). METHODS: Occurrence of GTCs was determined in 446 children with CAE who participated in a randomized clinical trial comparing ethosuximide, lamotrigine, and valproate as initial therapy for CAE. RESULTS: As of June 2014, the cohort had been followed for a median of 7.0 years since enrollment and 12% (53) have experienced at least one GTC. The median time to develop GTCs from initial therapy was 4.7 years. The median age at first GTC was 13.1 years. Fifteen (28%) were not on medications at the time of their first GTC. On univariate analysis, older age at enrollment was associated with a higher risk of GTCs (p=-0.0009), as was the duration of the shortest burst on the baseline EEG (p=0.037). Failure to respond to initial treatment (p<0.001) but not treatment assignment was associated with a higher rate of GTCs. Among patients initially assigned to ethosuximide, 94% (15/16) with GTCs experienced initial therapy failure (p<0.0001). A similar but more modest effect was noted in those initially treated with valproate (p=0.017) and not seen in those initially treated with lamotrigine. CONCLUSIONS: The occurrence of GTCs in a well-characterized cohort of children with CAE appears lower than previously reported. GTCs tend to occur late in the course of the disorder. Children initially treated with ethosuximide who are responders have a particularly low risk of developing subsequent GTCs.