Baricitinib for systemic lupus erythematosus: a double-blind, randomised, placebo-controlled, phase 3 trial (SLE-BRAVE-I).

BACKGROUND: Baricitinib is an oral selective inhibitor of Janus kinase 1 and 2 approved for the treatment of rheumatoid arthritis, atopic dermatitis, and alopecia areata. In a 24-week phase 2 study in patients with systemic lupus erythematosus (SLE), baricitinib 4 mg significantly improved SLE disease activity compared with placebo. The objective of this trial was to evaluate the efficacy and safety of baricitinib in patients with active SLE in a 52-week phase 3 study. METHODS: In a multicentre, double-blind, randomised, placebo-controlled, parallel-group, phase 3 study, SLE-BRAVE-I, patients (aged ≥18 years) with active SLE receiving stable background therapy were randomly assigned 1:1:1 to baricitinib 4 mg, 2 mg, or placebo once daily for 52 weeks with standard of care. Glucocorticoid tapering was encouraged but not required per protocol. The primary endpoint was the proportion of patients reaching an SLE Responder Index (SRI)-4 response at week 52 in the baricitinib 4 mg treatment group compared with placebo. The primary endpoint was assessed by logistic regression analysis with baseline disease activity, baseline corticosteroid dose, region, and treatment group in the model. Efficacy analyses were done on a modified intention-to-treat population, comprising all participants who were randomly assigned and received at least one dose of investigational product. Safety analyses were done on all randomly assigned participants who received at least one dose of investigational product and who did not discontinue from the study for the reason of lost to follow-up at the first post-baseline visit. This study is registered with ClinicalTrials.gov, NCT03616912. FINDINGS: 760 participants were randomly assigned and received at least one dose of baricitinib 4 mg (n=252), baricitinib 2 mg (n=255), or placebo (n=253). A significantly greater proportion of participants who received baricitinib 4 mg (142 [57%]; odds ratio 1·57 [95% CI 1·09 to 2·27]; difference with placebo 10·8 [2·0 to 19·6]; p=0·016), but not baricitinib 2 mg (126 [50%]; 1·14 [0·79 to 1·65]; 3·9 [-4·9 to 12·6]; p=0·47), reached SRI-4 response compared with placebo (116 [46%]). There were no significant differences between the proportions of participants in either baricitinib group reaching any of the major secondary endpoints compared with placebo, including glucocorticoid tapering and time to first severe flare. 26 (10%) participants receiving baricitinib 4 mg had serious adverse events, 24 (9%) participants receiving baricitinib 2 mg, and 18 (7%) participants receiving placebo. The safety profile of baricitinib in participants with SLE was consistent with the known baricitinib safety profile. INTERPRETATION: The primary endpoint in this study was met for the 4 mg baricitinib group. However, key secondary endpoints were not. No new safety signals were observed. FUNDING: Eli Lilly and Company.

Efficacy and safety of baricitinib for the treatment of hospitalised adults with COVID-19 (COV-BARRIER): a randomised, double-blind, parallel-group, placebo-controlled phase 3 trial.

BACKGROUND: Baricitinib is an oral selective Janus kinase 1/2 inhibitor with known anti-inflammatory properties. This study evaluates the efficacy and safety of baricitinib in combination with standard of care for the treatment of hospitalised adults with COVID-19. METHODS: In this phase 3, double-blind, randomised, placebo-controlled trial, participants were enrolled from 101 centres across 12 countries in Asia, Europe, North America, and South America. Hospitalised adults with COVID-19 receiving standard of care were randomly assigned (1:1) to receive once-daily baricitinib (4 mg) or matched placebo for up to 14 days. Standard of care included systemic corticosteroids, such as dexamethasone, and antivirals, including remdesivir. The composite primary endpoint was the proportion who progressed to high-flow oxygen, non-invasive ventilation, invasive mechanical ventilation, or death by day 28, assessed in the intention-to-treat population. All-cause mortality by day 28 was a key secondary endpoint, and all-cause mortality by day 60 was an exploratory endpoint; both were assessed in the intention-to-treat population. Safety analyses were done in the safety population defined as all randomly allocated participants who received at least one dose of study drug and who were not lost to follow-up before the first post-baseline visit. This study is registered with ClinicalTrials.gov, NCT04421027. FINDINGS: Between June 11, 2020, and Jan 15, 2021, 1525 participants were randomly assigned to the baricitinib group (n=764) or the placebo group (n=761). 1204 (79·3%) of 1518 participants with available data were receiving systemic corticosteroids at baseline, of whom 1099 (91·3%) were on dexamethasone; 287 (18·9%) participants were receiving remdesivir. Overall, 27·8% of participants receiving baricitinib and 30·5% receiving placebo progressed to meet the primary endpoint (odds ratio 0·85 [95% CI 0·67 to 1·08], p=0·18), with an absolute risk difference of -2·7 percentage points (95% CI -7·3 to 1·9). The 28-day all-cause mortality was 8% (n=62) for baricitinib and 13% (n=100) for placebo (hazard ratio [HR] 0·57 [95% CI 0·41-0·78]; nominal p=0·0018), a 38·2% relative reduction in mortality; one additional death was prevented per 20 baricitinib-treated participants. The 60-day all-cause mortality was 10% (n=79) for baricitinib and 15% (n=116) for placebo (HR 0·62 [95% CI 0·47-0·83]; p=0·0050). The frequencies of serious adverse events (110 [15%] of 750 in the baricitinib group vs 135 [18%] of 752 in the placebo group), serious infections (64 [9%] vs 74 [10%]), and venous thromboembolic events (20 [3%] vs 19 [3%]) were similar between the two groups. INTERPRETATION: Although there was no significant reduction in the frequency of disease progression overall, treatment with baricitinib in addition to standard of care (including dexamethasone) had a similar safety profile to that of standard of care alone, and was associated with reduced mortality in hospitalised adults with COVID-19. FUNDING: Eli Lilly and Company. TRANSLATIONS: For the French, Japanese, Portuguese, Russian and Spanish translations of the abstract see Supplementary Materials section.

Interdisciplinary Safety Evaluation for Learning and Decision-Making.

The FDA IND safety reporting Final Rule (21CFR 312.32) applies to all human drugs and biological products being studied under an Investigational New Drug (IND). A sponsor must file an IND safety report for any serious unexpected suspected adverse reaction (SUSAR) of a medicinal product being investigated. Some events may be obviously drug-related (e.g., agranulocytosis, anaphylactic reaction, drug-induced hepatic injury, Stevens-Johnson Syndrome). For serious adverse events that are not interpretable as individual occurrences, additional processes and procedures need to be employed for identifying and assessing risks in the accumulating safety data. The approaches shared in this manuscript apply principally to safety reporting of events that are anticipated to occur in the patient population-regardless of study participation. For these events, the study sponsor should periodically review the data in the aggregate and make a judgment as to whether there is a reasonable possibility of an event having been caused by the study drug rather than the underlying condition of the patient or a concomitant therapy. Factors cited for consideration are the size and consistency of the difference in event frequency between the test and control groups, supportive preclinical findings, evidence of a dose response relationship, plausible mechanism of action, known class effect and occurrence of other related adverse events. Examples are provided that demonstrate the flexibility sponsors have in meeting the spirit of the Final Rule; some combination and variation of methods from the examples could be employed. The important thing, as expressed by Jacqueline Corrigan-Curay (Director of the Office of Medical Policy, Center for Drug Evaluation and Research, FDA), is to have a thoughtful process; a system in place to look for clinically important imbalances, applying the best clinical and quantitative judgment, while maintaining trial integrity (Ball et al. in Interdisciplinary aggregate assessments for IND safety reporting: a dialogue among colleagues from industry, Academia and the FDA. ASA biopharmaceutical section regulatory-industry statistics workshop, 2018).

Baricitinib-associated changes in global gene expression during a 24-week phase II clinical systemic lupus erythematosus trial implicates a mechanism of action through multiple immune-related pathways.

OBJECTIVE: To characterise the molecular pathways impacted by the pharmacologic effects of the Janus kinase (JAK) 1 and JAK2 inhibitor baricitinib in SLE. METHODS: In a phase II, 24-week, randomised, placebo-controlled, double-blind study (JAHH), RNA was isolated from whole blood in 274 patients and analysed using Affymetrix HTA2.0 array. Serum cytokines were measured using ultrasensitive quantitative assays. RESULTS: Gene expression profiling demonstrated an elevation of STAT1, STAT2 and multiple interferon (IFN) responsive genes at baseline in patients with SLE. Statistical and gene network analyses demonstrated that baricitinib treatment reduced the mRNA expression of functionally interconnected genes involved in SLE including STAT1-target, STAT2-target and STAT4-target genes and multiple IFN responsive genes. At baseline, serum cytokines IFN-α, IFN-γ, interleukin (IL)-12p40 and IL-6 were measurable and elevated above healthy controls. Treatment with baricitinib significantly decreased serum IL-12p40 and IL-6 cytokine levels at week 12, which persisted through week 24. CONCLUSION: Baricitinib treatment induced significant reduction in the RNA expression of a network of genes associated with the JAK/STAT pathway, cytokine signalling and SLE pathogenesis. Baricitinib consistently reduced serum levels of two key cytokines implicated in SLE pathogenesis, IL-12p40 and IL-6.

Clinical Trial Drug Safety Assessment for Studies and Submissions Impacted by COVID-19.

Abstract-In this article, we provide guidance on how safety analyses and reporting of clinical trial safety data may need to be modified, given potential impact from the COVID-19 pandemic. Impact could include missed visits, alternative methods for assessments (such as virtual visits), alternative locations for assessments (such as local labs), and study drug interruptions. Starting from the safety analyses typically included in Clinical Study Reports for Phase 2-4 clinical trials and integrated submission documents, we assess what modifications might be needed. If the impact from COVID-19 affects treatment arms equally, analyses of adverse events from controlled data can, to a large extent, remain unchanged. However, interpretation of summaries from uncontrolled data (summaries that include open-label extension data) will require even more caution than usual. Special consideration will be needed for safety topics of interest, especially events expected to have a higher incidence due to a COVID-19 infection or due to quarantine or travel restrictions (e.g., depression). Analyses of laboratory measurements may need to be modified to account for the combination of measurements from local and central laboratories.

Adaptation of the robust method to large distributions of reference values: program modifications and comparison of alternative computational methods.

The objective of this research was to compute reference limits using reference values from patients entering pharmaceutical development clinical trials by the nonparametric method and the robust method of Horn and Pesce, with and without outlier exclusion, and compare the methods with respect to influence on the limits. Reference limits were computed for 38 analytes with over 130,000 subjects contributing reference values. Subjects were partitioned into 10 demographic strata for limit computation. Limits were computed for both 95- and 98-percentile reference intervals by both methods. For each reference interval and method, the limits were calculated with and without outliers. Outliers were excluded by the Horn algorithm. Irrespective of method, reference limits were expanded with the 98-percentile interval, but some expansions were small. Outlier exclusion contracted limits with more influence on the upper limit. The robust method contracted the upper limit to a meaningful degree and slightly expanded the lower limit for many analytes. Outlier exclusion and computation by the robust method have an increasing influence on analytes with right-skewed distributions of reference values from large populations not screened to exclude common, stable diseases and environmental factors that might affect analyte variability. The method has advantages for computation of reference limits used in clinical trial analyses.

Reference Limits for Outlier Analyses in Randomized Clinical Trials.

BACKGROUND: Reference limits used in clinical medicine to screen and manage patients are typically developed nonparametrically using reference values from a limited number of healthy subjects using a 95th percentile reference interval. We have evaluated alternative methods of computation and the resulting limits for use in the analyses of treatment-emergent outliers in clinical trials. METHODS: We developed a set of alternative reference limits for 38 laboratory analytes based on alternative statistical methods and assessed their relative performance in clinical trial analysis. Performance assessment was based on the clinical credibility of the limits, inferential statistical performance, consideration of incidences for the test drug and control (placebo) in cases where the drug was reasonably believed to be associated with a change in an analyte (positive cases), and in cases where prior analyses failed to demonstrate a change associated with the drug (negative cases). RESULTS: Based on consideration of these cases, no single method resulted in optimal limits for all cases considered. However, with the limits developed using clinical trial subjects' values at baseline as reference values, excluding outliers, the robust method and the 98th percentile interval appeared to produce optimal limits across the greatest number of cases considered. CONCLUSION: Although no single method of limit computation will result in optimal limits for all outlier analyses for all analytes across all clinical trials, the 98th percentile reference interval robust limits based on clinical trial reference values appeared superior to multiple alternatives considered for such analyses.

Reporting Adverse Drug Reactions in Product Labels.

Product labels are intended to provide health care professionals with clear and concise prescribing information that will enhance the safe and effective use of drug products. In this manuscript, we offer suggestions to improve product labels. First, we recommend that product labels that include comparator data be changed to include adjusted incidence proportions (or adjusted incidence rates when needed and appropriate) for adverse drug reactions that are somewhat common. Second, we believe that including comparator incidence in product labels is a good practice, as it gives health care providers and patients appropriate information to put the absolute risks in perspective. Finally, we recommend changing the practice of reporting extremely rare events based on the "Rule of 3" in the Summary of Product Characteristics in Europe. We recommend that these adverse drug reactions be put in a separate table from other adverse drug reactions with a note that it is difficult to reliably estimate their incidences. In exceptional circumstances, it may be possible to present an estimate of their incidence based on postmarketing data. We believe the proposed changes could help product labels to better reflect the risk of a drug relative to a comparator.

The FDA's Final Rule on Expedited Safety Reporting: Statistical Considerations.

In March 2011, a Final Rule for expedited reporting of serious adverse events took effect in the United States for studies conducted under an Investigational New Drug (IND) application. In December 2012, the U.S. Food and Drug Administration (FDA) promulgated a final Guidance describing the operationalization of this Final Rule. The Rule and Guidance clarified that a clinical trial sponsor should have evidence suggesting causality before defining an unexpected serious adverse event as a suspected adverse reaction that would require expedited reporting to the FDA. The Rule's emphasis on the need for evidence suggestive of a causal relation should lead to fewer events being reported but, among those reported, a higher percentage actually being caused by the product being tested. This article reviews the practices that were common before the Final Rule was issued and the approach the New Rule specifies. It then discusses methods for operationalizing the Final Rule with particular focus on relevant statistical considerations. It concludes with a set of recommendations addressed to Sponsors and to the FDA in implementing the Final Rule.

Seeing is believing: good graphic design principles for medical research.

Have you noticed when you browse a book, journal, study report, or product label how your eye is drawn to figures more than to words and tables? Statistical graphs are powerful ways to transparently and succinctly communicate the key points of medical research. Furthermore, the graphic design itself adds to the clarity of the messages in the data. The goal of this paper is to provide a mechanism for selecting the appropriate graph to thoughtfully construct quality deliverables using good graphic design principles. Examples are motivated by the efforts of a Safety Graphics Working Group that consisted of scientists from the pharmaceutical industry, Food and Drug Administration, and academic institutions.

Protocol for a mixed-methods study of supplemental oxygen in pulmonary fibrosis.

BACKGROUND: Little is known about whether or how supplemental oxygen affects patients with pulmonary fibrosis. METHODS/DESIGN: A mixed-methods study is described. Patients with pulmonary fibrosis, informal caregivers of pulmonary fibrosis patients and practitioners who prescribe supplemental oxygen will be interviewed to gather data on perceptions of how supplemental oxygen impacts patients. In addition, three hundred pulmonary fibrosis patients who do not use daytime supplemental oxygen will be recruited to participate in a longitudinal, pre-/post- study in which patient-reported outcome (PRO) and activity data will be collected at baseline, immediately before daytime supplemental oxygen is initiated, and then once and again 9-12 months later. Activity data will be collected using accelerometers and portable GPS data recorders. The primary outcome is change in dyspnea from before to one month after supplemental oxygen is initiated. Secondary outcomes include scores from PROs to assess cough, fatigue and quality of life as well as the activity data. In exploratory analyses, we will use longitudinal data analytic techniques to assess the trajectories of outcomes over time while controlling for potentially influential variables. DISCUSSION: Throughout the study and at its completion, results will be posted on the website for our research program (the Participation Program for Pulmonary Fibrosis or P3F) at http://www.pulmonaryfibrosisresearch.org.

Prospective safety surveillance of GH-deficient adults: comparison of GH-treated vs untreated patients.

CONTEXT: In clinical practice, the safety profile of GH replacement therapy for GH-deficient adults compared with no replacement therapy is unknown. OBJECTIVE: The objective of this study was to compare adverse events (AEs) in GH-deficient adults who were GH-treated with those in GH-deficient adults who did not receive GH replacement. DESIGN AND SETTING: This was a prospective observational study in the setting of US clinical practices. PATIENTS AND OUTCOME MEASURES: AEs were compared between GH-treated (n = 1988) and untreated (n = 442) GH-deficient adults after adjusting for baseline group differences and controlling the false discovery rate. The standardized mortality ratio was calculated using US mortality rates. RESULTS: After a mean follow-up of 2.3 years, there was no significant difference in rates of death, cancer, intracranial tumor growth or recurrence, diabetes, or cardiovascular events in GH-treated compared with untreated patients. The standardized mortality ratio was not increased in either group. Unexpected AEs (GH-treated vs untreated, P ≤ .05) included insomnia (6.4% vs 2.7%), dyspnea (4.2% vs 2.0%), anxiety (3.4% vs 0.9%), sleep apnea (3.3% vs 0.9%), and decreased libido (2.1% vs 0.2%). Some of these AEs were related to baseline risk factors (including obesity and cardiopulmonary disease), higher GH dose, or concomitant GH side effects. CONCLUSIONS: In GH-deficient adults, there was no evidence for a GH treatment effect on death, cancer, intracranial tumor recurrence, diabetes, or cardiovascular events, although the follow-up period was of insufficient duration to be conclusive for these long-term events. The identification of unexpected GH-related AEs reinforces the fact that patient selection and GH dose titration are important to ensure safety of adult GH replacement.

Comparison of Bayesian and frequentist meta-analytical approaches for analyzing time to event data.

Using meta-analysis in health care research is a common practice. Here we are interested in methods used for analysis of time-to-event data. Particularly, we are interested in their performance when there is a low event rate. We consider three methods based on the Cox proportional hazards model, including a Bayesian approach. A formal comparison of the methods is conducted using a simulation study. In our simulation we model two treatments and consider several scenarios.

Meta-analysis of clinical trial safety data in a drug development program: answers to frequently asked questions.

BACKGROUND: Meta-analyses of clinical trial safety data have risen in importance beyond regulatory submissions. During drug development, sponsors need to recognize safety signals early and adjust the development program accordingly, so as to facilitate the assessment of causality. Once a product is marketed, sponsors add postapproval clinical trial data to the body of information to help understand existing safety concerns or those that arise from other postapproval data sources, such as spontaneous reports. PURPOSE: This article focuses on common questions encountered when designing and performing a meta-analysis of clinical trial safety data. Although far from an exhaustive set of questions, they touch on some basic and often misunderstood features of conducting such meta-analyses. METHODS: The authors reviewed the current literature and used their combined experience with regulatory and other uses of meta-analysis to answer common questions that arise when performing meta-analyses of safety data. RESULTS: We addressed the following topics: choice of studies to pool, effects of the method of ascertainment, use of patient-level data compared to trial-level data, the need (or not) for multiplicity adjustments, heterogeneity of effects and sources of it, and choice of fixed effects versus random effects. LIMITATIONS: The list of topics is not exhaustive and the opinions offered represent only our perspective; we recognize that there may be other valid perspectives. CONCLUSIONS: Meta-analysis can be a valuable tool for evaluating safety questions, but a number of methodological choices need to be made in designing and conducting any meta-analysis. This article provides advice on some of the more commonly encountered choices.

Planning and core analyses for periodic aggregate safety data reviews.

BACKGROUND: In 2009, the Safety Planning, Evaluation and Reporting Team gave detailed recommendations for a well-planned and systematic approach for safety data collection and analysis. Important aspects of this approach included regular reviews of aggregate data by a multidisciplinary team focusing on safety. PURPOSE: This article provides information to facilitate the planning and implementation of aggregate data reviews. METHODS: Our recommendations are based on experience of the authors and review of relevant literature. RESULTS: We present information regarding the planning of aggregate data reviews as well as examples of data displays that are useful for many different compounds. A subset of these data displays could form a set of 'core' analyses to be generated for aggregate data reviews.

Comparison of several imputation methods for missing baseline data in propensity scores analysis of binary outcome.

We performed a simulation study comparing the statistical properties of the estimated log odds ratio from propensity scores analyses of a binary response variable, in which missing baseline data had been imputed using a simple imputation scheme (Treatment Mean Imputation), compared with three ways of performing multiple imputation (MI) and with a Complete Case analysis. MI that included treatment (treated/untreated) and outcome (for our analyses, outcome was adverse event [yes/no]) in the imputer's model had the best statistical properties of the imputation schemes we studied. MI is feasible to use in situations where one has just a few outcomes to analyze. We also found that Treatment Mean Imputation performed quite well and is a reasonable alternative to MI in situations where it is not feasible to use MI. Treatment Mean Imputation performed better than MI methods that did not include both the treatment and outcome in the imputer's model.

Recommendations for safety planning, data collection, evaluation and reporting during drug, biologic and vaccine development: a report of the safety planning, evaluation, and reporting team.

BACKGROUND: The Safety Planning, Evaluation and Reporting Team (SPERT) was formed in 2006 by the Pharmaceutical Research and Manufacturers of America. PURPOSE: SPERT's goal was to propose a pharmaceutical industry standard for safety planning, data collection, evaluation, and reporting, beginning with planning first-in-human studies and continuing through the planning of the post-product-approval period. METHODS: SPERT's recommendations are based on our review of relevant literature and on consensus reached in our discussions. RESULTS: An important recommendation is that sponsors create a Program Safety Analysis Plan early in development. We also give recommendations for the planning of repeated, cumulative meta-analyses of the safety data obtained from the studies conducted within the development program. These include clear definitions of adverse events of special interest and standardization of many aspects of data collection and study design. We describe a 3-tier system for signal detection and analysis of adverse events and highlight proposals for reducing "false positive" safety findings. We recommend that sponsors review the aggregated safety data on a regular and ongoing basis throughout the development program, rather than waiting until the time of submission. LIMITATIONS: We recognize that there may be other valid approaches. CONCLUSIONS: The proactive approach we advocate has the potential to benefit patients and health care providers by providing more comprehensive safety information at the time of new product marketing and beyond.

Growth hormone treatment of early growth failure in toddlers with Turner syndrome: a randomized, controlled, multicenter trial.

CONTEXT: Typically, growth failure in Turner syndrome (TS) begins prenatally, and height sd score (SDS) declines progressively from birth. OBJECTIVE: This study aimed to determine whether GH treatment initiated before 4 yr of age in girls with TS could prevent subsequent growth failure. Secondary objectives were to identify factors associated with treatment response, to determine whether outcome could be predicted by a regression model using these factors, and to assess the safety of GH treatment in this young cohort. DESIGN: This study was a prospective, randomized, controlled, open-label, multicenter clinical trial (Toddler Turner Study, August 1999 to August 2003). SETTING: The study was conducted at 11 U.S. pediatric endocrine centers. SUBJECTS: Eighty-eight girls with TS, aged 9 months to 4 yr, were enrolled. INTERVENTIONS: Interventions comprised recombinant GH (50 mug/kg.d; n = 45) or no treatment (n = 43) for 2 yr. MAIN OUTCOME MEASURE: The main outcome measure was baseline-to-2-yr change in height SDS. RESULTS: Short stature was evident at baseline (mean length/height SDS = -1.6 +/- 1.0 at mean age 24.0 +/- 12.1 months). Mean height SDS increased in the GH group from -1.4 +/- 1.0 to -0.3 +/- 1.1 (1.1 SDS gain), whereas it decreased in the control group from -1.8 +/- 1.1 to -2.2 +/- 1.2 (0.5 SDS decline), resulting in a 2-yr between-group difference of 1.6 +/- 0.6 SDS (P < 0.0001). The baseline variable that correlated most strongly with 2-yr height gain was the difference between mid-parental height SDS and subjects' height SDS (r = 0.32; P = 0.04). Although attained height SDS at 2 yr could be predicted with good accuracy using baseline variables alone (R(2) = 0.81; P < 0.0001), prediction of 2-yr change in height SDS required inclusion of initial treatment response data (4-month or 1-yr height velocity) in the model (R(2) = 0.54; P < 0.0001). No new or unexpected safety signals associated with GH treatment were detected. CONCLUSION: Early GH treatment can correct growth failure and normalize height in infants and toddlers with TS.

Growth hormone is effective in treatment of short stature associated with short stature homeobox-containing gene deficiency: Two-year results of a randomized, controlled, multicenter trial.

BACKGROUND: The short stature homeobox-containing gene, SHOX, located on the distal ends of the X and Y chromosomes, encodes a homeodomain transcription factor responsible for a significant proportion of long-bone growth. Patients with mutations or deletions of SHOX, including those with Turner syndrome (TS) who are haplo-insufficient for SHOX, have variable degrees of growth impairment, with or without a spectrum of skeletal anomalies consistent with dyschondrosteosis. OBJECTIVE: Our objective was to determine the efficacy of GH in treating short stature associated with short stature homeobox-containing gene deficiency (SHOX-D). DESIGN AND METHODS: Fifty-two prepubertal subjects (24 male, 28 female; age, 3.0-12.3 yr) with a molecularly proven SHOX gene defect and height below the third percentile for age and gender (or height below the 10th percentile and height velocity below the 25th percentile) were randomized to either a GH-treatment group (n = 27) or an untreated control group (n = 25) for 2 yr. To compare the GH treatment effect between subjects with SHOX-D and those with TS, a third study group, 26 patients with TS aged 4.5-11.8 yr, also received GH. Between-group comparisons of first-year and second-year height velocity, height sd score, and height gain (cm) were performed using analysis of covariance accounting for diagnosis, sex, and baseline age. RESULTS: The GH-treated SHOX-D group had a significantly greater first-year height velocity than the untreated control group (mean +/- se, 8.7 +/- 0.3 vs. 5.2 +/- 0.2 cm/yr; P < 0.001) and similar first-year height velocity to GH-treated subjects with TS (8.9 +/- 0.4 cm/yr; P = 0.592). GH-treated subjects also had significantly greater second-year height velocity (7.3 +/- 0.2 vs. 5.4 +/- 0.2 cm/yr; P < 0.001), second-year height sd score (-2.1 +/- 0.2 vs.-3.0 +/- 0.2; P < 0.001) and second-year height gain (16.4 +/- 0.4 vs. 10.5 +/- 0.4 cm; P < 0.001) than untreated subjects. CONCLUSIONS: This large-scale, randomized, multicenter clinical trial in subjects with SHOX-D demonstrates marked, highly significant, GH-stimulated increases in height velocity and height SDS during the 2-yr study period. The efficacy of GH treatment in subjects with SHOX-D was equivalent to that seen in subjects with TS. We conclude that GH is effective in improving the linear growth of patients with various forms of SHOX-D.

Genotypes and phenotypes in children with short stature: clinical indicators of SHOX haploinsufficiency.

BACKGROUND: Short stature affects approximately 2% of children, representing one of the more frequent disorders for which clinical attention is sought during childhood. Despite assumed genetic heterogeneity, mutations or deletions of the short stature homeobox-containing gene (SHOX) are found quite frequently in subjects with short stature. Haploinsufficiency of the SHOX gene causes short stature with highly variable clinical severity, ranging from isolated short stature without dysmorphic features to Léri-Weill syndrome, and with no functional copy of the SHOX gene, Langer syndrome. METHODS: To characterise the clinical and molecular spectrum of SHOX deficiency in childhood we assessed the association between genotype and phenotype in a large cohort of children of short stature from 14 countries. RESULTS: Screening of 1608 unrelated individuals with sporadic or familial short stature revealed SHOX mutations or deletions in 68 individuals (4.2%): complete deletions in 48 (70.6%), partial deletions in 4 (5.9%) and point mutations in 16 individuals (23.5%). Although mean height standard deviation score (SDS) was not different between participants of short stature with or without identified SHOX gene defects (-2.6 vs -2.6), detailed examination revealed that certain bone deformities and dysmorphic signs, such as short forearm and lower leg, cubitus valgus, Madelung deformity, high-arched palate and muscular hypertrophy, differed markedly between participants with or without SHOX gene defects (p<0.001). Phenotypic data were also compared for 33 children with Turner syndrome in whom haploinsufficiency of SHOX is thought to be responsible for the height deficit. CONCLUSION: A phenotype scoring system was developed that could assist in identifying the most appropriate subjects for SHOX testing. This study offers a detailed genotype-phenotype analysis in a large cohort of children of short stature, and provides quantitative clinical guidelines for testing of the SHOX gene.