Respiratory Effects of the Atypical Tricyclic Antidepressant Tianeptine in Human Models of Opioid-induced Respiratory Depression.

BACKGROUND: Animal data suggest that the antidepressant and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor modulator tianeptine is able to prevent opioid-induced respiratory depression. The hypothesis was that oral or intravenous tianeptine can effectively prevent or counteract opioid-induced respiratory depression in humans. METHODS: Healthy male and female volunteers participated in two studies that had a randomized, double blind, placebo-controlled, crossover design. First, oral tianeptine (37.5-, 50-, and 100-mg doses with 8 subjects) pretreatment followed by induction of alfentanil-induced respiratory depression (alfentanil target concentration, 100 ng/ml) was tested. Primary endpoint was ventilation at an extrapolated end-tidal carbon dioxide concentration of 55 mmHg (V̇E55). Next, the ability of four subsequent and increasing infusions of intravenous tianeptine (target tianeptine plasma concentrations 400, 1,000, 1,500, and 2,000 ng/ml, each given over 15 min) to counteract remifentanil-induced respiratory depression was determined in 15 volunteers. Ventilation was measured at isohypercpania (baseline ventilation 20 ± 2 l/min). The primary endpoint was minute ventilation during the 60 min of tianeptine versus placebo infusion. RESULTS: Alfentanil reduced V̇E55 to 13.7 (95% CI, 8.6 to 18.8) l/min after placebo pretreatment and to 17.9 (10.2 to 25.7) l/min after 50-mg tianeptine pretreatment (mean difference between treatments 4.2 (-11.5 to 3.0) l/min, P = 0.070). Intravenous tianeptine in the measured concentration range of 500 to 2,000 ng/ml did not stimulate ventilation but instead worsened remifentanil-induced respiratory depression: tianeptine, 9.6 ± 0.8 l/min versus placebo 15.0 ± 0.9 l/min; mean difference, 5.3 l/min; 95% CI, 2.5 to 8.2 l/min; P = 0.001, after 1 h of treatment. CONCLUSIONS: Neither oral nor intravenous tianeptine were respiratory stimulants. Intravenous tianeptine over the concentration range of 500 to 2000 ng/ml worsened respiratory depression induced by remifentanil.

Ensuring Stakeholder Feedback in the Design and Conduct of Clinical Trials for Rare Diseases: ISCTM Position Paper of the Orphan Disease Working Group.

The 1983 Orphan Drug Act in the United States (US) changed the landscape for development of therapeutics for rare or orphan diseases, which collectively affect approximately 300 million people worldwide, half of whom are children. The act has undoubtedly accelerated drug development for orphan diseases, with over 6,400 orphan drug applications submitted to the US Food and Drug Administration (FDA) from 1983 to 2023, including 350 drugs approved for over 420 indications. Drug development in this population is a global and collaborative endeavor. This position paper of the International Society for Central Nervous System Clinical Trials and Methodology (ISCTM) describes some potential best practices for the involvement of key stakeholder feedback in the drug development process. Stakeholders include advocacy groups, patients and caregivers with lived experience, public and private research institutions (including academia and pharmaceutical companies), treating clinicians, and funders (including the government and independent foundations). The authors articulate the challenges of drug development in orphan diseases and propose methods to address them. Challenges range from the poor understanding of disease history to development of endpoints, targets, and clinical trials designs, to finding solutions to competing research priorities by involved parties.

Implications of Pediatric Initiatives on CNS Drug Development for All Ages-2020 and Beyond: Second of Three Sets of Expanded Proceedings from the 2020 ISCTM Autumn Conference on Pediatric Drug Development.

This article expands upon a session, titled "Implications of Pediatric Initiatives on CNS Drug Development for All Ages-2020 and Beyond," that was presented as part of a two-day meeting on pediatric drug development at the International Society for Central Nervous System (CNS) Clinical Trials and Methodology (ISCTM) Autumn Conference in Boston, Massachusetts, in October 2020. Speakers from various areas of pediatric drug development addressed a variety of implications of including children in drug development programs. The speakers wrote summaries of their talks, which are included here. The session's lead chair was Dr. Gahan Pandina, who wrote introductory and closing comments. Dr. Joseph Horrigan addressed the current landscape of pediatric development programs. Dr. Gahan Pandina addressed how the approach to research in pediatric populations affects the drug development process and vice versa. Dr. Alison Bateman-House discussed the ethical implications of research in the pediatric population. Dr. Luca Pani discussed some of the global regulatory issues and challenges concerning research in pediatric patients. Dr. Judith Kando served as a discussant and posed new questions about means of facilitating pediatric research. Finally, Dr. Gahan Pandina provided closing comments and tied together the presented issues. This paper should serve as an expert-informed reference to those interested and involved in CNS drug development programs that are aimed at children and/or required, through regulations, to include children as part of the approval process.

Development of trofinetide for the treatment of Rett syndrome: from bench to bedside.

Rett syndrome (RTT) is rare neurodevelopmental disorder caused by mutations in the MECP2 gene that encodes methyl-CpG-binding protein 2 (MeCP2), a DNA-binding protein with roles in epigenetic regulation of gene expression. Functional loss of MeCP2 results in abnormal neuronal maturation and plasticity, characterized by loss of verbal communication and loss of fine and gross motor function, among others. Trofinetide, a synthetic analog of glycine-proline-glutamate, was approved by the US Food and Drug Administration for the treatment of RTT in adult and pediatric patients aged 2 years and older. Here, we present the development of trofinetide from bench research to clinical studies and emphasize how the collaboration between academia, the pharmaceutical industry, and patient advocacy led to the recent approval. The bench-to-bedside development of trofinetide underscores the value of collaboration between these groups in the development and approval of treatments for rare diseases.

A Double-Blind, Randomized, Placebo-Controlled Clinical Study of Trofinetide in the Treatment of Fragile X Syndrome.

BACKGROUND: We analyze the safety and tolerability of trofinetide and provide a preliminary evaluation of its efficacy in adolescent and adult males with fragile X syndrome. METHODS: This study was an exploratory, phase 2, multicenter, double-blind, placebo-controlled, parallel group study of the safety and tolerability of orally administered trofinetide in 72 adolescent and adult males with fragile X syndrome. Subjects were randomly assigned in a 1:1:1 ratio to 35 or 70 mg/kg twice daily trofinetide or placebo for 28 days. Safety assessments included adverse events, clinical laboratory tests, vital signs, electrocardiograms, physical examinations, and concomitant medications. Efficacy measurements were categorized into four efficacy domains, which related to clinically relevant phenotypic dimensions of impairment associated with fragile X syndrome. RESULTS: Both 35 and 70 mg/kg dose levels of trofinetide were well tolerated and appeared to be generally safe. Trofinetide at the 70 mg/kg dose level demonstrated efficacy compared with placebo based on prespecified criteria. On the basis of a permutation test, the probability of a false-positive outcome for the achieved prespecified success was 0.045. In the group analysis, improvement from treatment baseline was demonstrated on three fragile X syndrome-specific outcome measures. CONCLUSIONS: Trofinetide was well tolerated in adolescent and adult males with fragile X syndrome. Despite the relatively short duration of the study, a consistent signal of efficacy at the higher dose was observed in both caregiver and clinician assessments, based on a novel analytical model incorporating evaluation of multiple key symptom areas of fragile X syndrome. This finding suggests a potential for trofinetide treatment to provide clinically meaningful improvement in core fragile X syndrome symptoms.

Bupropion extended release compared with escitalopram: effects on sexual functioning and antidepressant efficacy in 2 randomized, double-blind, placebo-controlled studies.

OBJECTIVE: To compare the effects on sexual functioning and the antidepressant efficacy of once-daily bupropion extended release (XL) and escitalopram in adults with major depressive disorder (MDD). METHOD: Adult outpatients with moderate to severe DSM-IV-defined MDD and normal sexual functioning were randomly assigned to receive bupropion XL (300-450 mg/day; N = 276), escitalopram (10-20 mg/day; N = 281), or placebo (N = 273) for up to 8 weeks in 2 identically designed, randomized, double-blind, parallel-group studies (study 1 conducted from February 6, 2003, to June 10, 2004; study 2 conducted from January 21, 2003, to June 15, 2004). Data were analyzed prospectively for each study individually, and pooled data were analyzed retrospectively. RESULTS: In both the individual studies and the pooled dataset, the incidence of orgasm dysfunction at week 8 (primary endpoint) and the incidence of worsened sexual functioning at the end of the treatment period were statistically significantly lower with bupropion XL than with escitalopram (p < .05), not statistically different between bupropion XL and placebo (p > or = .067), and statistically significantly higher with escitalopram than with placebo (p < or = .001). The percentages of patients with orgasm dysfunction at week 8 in study 1, study 2, and the pooled dataset, respectively, were 13%, 16%, and 15% with bupropion XL; 32%, 29%, and 30% with escitalopram; and 11%, 8%, and 9% with placebo. The respective percentages of patients with worsened sexual functioning at the end of the treatment period were 18%, 22%, and 20% with bupropion XL; 37%, 34%, and 36% with escitalopram; and 14%, 16%, and 15% with placebo. Mean changes in Changes in Sexual Functioning Questionnaire scores for all domains at week 8 were statistically significantly worse for escitalopram compared with bupropion XL (p < or = .05). Separation from placebo could not be established at a statistical .05 level for bupropion on 17-item Hamilton Rating Scale for Depression (HAM-D-17) total score. However, escitalopram showed statistical superiority to placebo on HAM-D-17 total score in one of the 2 studies and in the pooled data. Bupropion XL did not statistically differ from escitalopram with respect to mean change in HAM-D-17 total score, HAM-D-17 response or remission rates, percentage of patients much or very much improved on Clinical Global Impressions-Improvement scale scores, or mean changes in the Hospital Anxiety and Depression (HAD) scale total score or Clinical Global Impressions-Severity of Illness scale score at week 8. CONCLUSIONS: Bupropion XL had a sexual tolerability profile significantly better than that of escitalopram with similar HAM-D-17 remission rates and HAD total scores in patients with MDD.

Analysis of electrocardiographic data following use of paroxetine in pediatric depression and obsessive-compulsive disorder.

OBJECTIVE: This retrospective analysis of electrocardiographic (ECG) data investigated the cardiovascular effects of paroxetine 10-50 mg/day in pediatric patients (7-18 years of age). Data were collected from three 8- to 10-week, randomized, placebo-controlled, double-blind trials of paroxetine in pediatric patients with major depressive disorder or obsessive-compulsive disorder. METHOD: Electrocardiograms (ECGs) were retrospectively retrieved from 63 study sites in the United States and Canada. Only patients with at least one screening and one on-treatment ECG were included. ECGs were analyzed for heart rate, QT interval corrected using Bazett's formula (QTcB) and Fridericia's formula (QTcF), at screening and while being treated. PR, R-R, and QRS intervals and the maximum change in QTcB and QTcF from screening to endpoint were determined. Clinically significant thresholds were defined a priori. RESULTS: A total of 1,451 ECGs from 449 patients receiving placebo (n = 207), paroxetine (n = 200), or imipramine (n = 42) were analyzed. Treatment with paroxetine did not significantly increase QTcB or QTcF or any ECG parameters compared with placebo. Treatment with imipramine significantly increased heart rate and QTcB, R-R, and QRS intervals compared with either paroxetine or placebo. CONCLUSIONS: Data from this retrospective study indicate that paroxetine (10-50 mg/day) is unlikely to be associated with significant ECG changes in medically healthy pediatric patients.

Bupropion XL in adults with attention-deficit/hyperactivity disorder: a randomized, placebo-controlled study.

BACKGROUND: Data remain limited on treatment strategies for adults with attention-deficit/hyperactivity disorder (ADHD). This study evaluated the efficacy and safety of an extended-release, once-daily formulation of bupropion (XL) in the treatment of adults with ADHD. METHODS: This multisite, placebo-controlled, 8-week prospective trial evaluated 162 adult patients diagnosed with ADHD (combined and inattentive types). Subjects were treated with up to 450 mg/day of bupropion XL. The primary efficacy endpoint was the proportion of ADHD responders (defined as at least a 30% reduction in the investigator-rated ADHD Rating Scale score) at week 8 (last observation carried forward [LOCF]). RESULTS: Bupropion XL responders (53%) exceeded placebo responders (31%) (p =.004 at week 8) with a significantly greater proportion of bupropion XL responders as early as week 2 (p = .01). Treatment effect size calculated for the ADHD Rating Scale total score was .6. Bupropion XL appeared to provide sustained benefit throughout the day compared with placebo (morning p =.033, afternoon p =.004, evening p = .024). Bupropion XL was safe and well tolerated, with no serious or unexpected adverse events and a low rate of drug-related study discontinuation (5%). CONCLUSIONS: The results from this multisite study indicate that bupropion XL is an effective and well-tolerated nonstimulant treatment for adult ADHD.

Measuring social communication behaviors as a treatment endpoint in individuals with autism spectrum disorder.

Social communication impairments are a core deficit in autism spectrum disorder. Social communication deficit is also an early indicator of autism spectrum disorder and a factor in long-term outcomes. Thus, this symptom domain represents a critical treatment target. Identifying reliable and valid outcome measures for social communication across a range of treatment approaches is essential. Autism Speaks engaged a panel of experts to evaluate the readiness of available measures of social communication for use as outcome measures in clinical trials. The panel held monthly conference calls and two face-to-face meetings over 14 months. Key criteria used to evaluate measures included the relevance to the clinical target, coverage of the symptom domain, and psychometric properties (validity and reliability, as well as evidence of sensitivity to change). In all, 38 measures were evaluated and 6 measures were considered appropriate for use, with some limitations. This report discusses the relative strengths and weaknesses of existing social communication measures for use in clinical trials and identifies specific areas in need of further development.

Measuring repetitive behaviors as a treatment endpoint in youth with autism spectrum disorder.

Restricted interests and repetitive behaviors vary widely in type, frequency, and intensity among children and adolescents with autism spectrum disorder. They can be stigmatizing and interfere with more constructive activities. Accordingly, restricted interests and repetitive behaviors may be a target of intervention. Several standardized instruments have been developed to assess restricted interests and repetitive behaviors in the autism spectrum disorder population, but the rigor of psychometric assessment is variable. This article evaluated the readiness of available measures for use as outcome measures in clinical trials. The Autism Speaks Foundation assembled a panel of experts to examine available instruments used to measure restricted interests and repetitive behaviors in youth with autism spectrum disorder. The panel held monthly conference calls and two face-to-face meetings over 14 months to develop and apply evaluative criteria for available instruments. Twenty-four instruments were evaluated and five were considered "appropriate with conditions" for use as outcome measures in clinical trials. Ideally, primary outcome measures should be relevant to the clinical target, be reliable and valid, and cover the symptom domain without being burdensome to subjects. The goal of the report was to promote consensus across funding agencies, pharmaceutical companies, and clinical investigators about advantages and disadvantages of existing outcome measures.

A Phase II study of a histamine H3 receptor antagonist GSK239512 for cognitive impairment in stable schizophrenia subjects on antipsychotic therapy.

This Phase II exploratory study assessed GSK239512, a brain penetrant histamine H3 receptor antagonist, versus placebo on cognitive impairment in 50 stable outpatients with schizophrenia. Subjects were randomized to placebo or GSK239512 for 7 weeks (4 weeks titration). GSK239512 was associated with a small positive effect size (ES) on the CogState Schizophrenia Battery (CSSB) Composite Score (ES=0.29, CI=-0.40, 0.99) relative to placebo (primary endpoint). GSK239512's ES on CSSB domains were generally positive or neutral except Processing Speed, which favored placebo (ES=-0.46). Effects on the MATRICS Consensus Cognitive Battery were mostly neutral or favored placebo. GSK239512 was generally well tolerated with an adverse event profile consistent with the known class pharmacology. There was no evidence of overall beneficial effects of GSK239512 for CIAS in this population.

A randomized, double-blind, placebo-controlled, 16-week study of the H3 receptor antagonist, GSK239512 as a monotherapy in subjects with mild-to-moderate Alzheimer's disease.

INTRODUCTION: Histaminergic H3 receptors may play a role in modulating cholinergic and monoaminergic neurotransmission. This Phase II study evaluated the efficacy and safety of GSK239512, a highly potent, brain penetrant H3 receptor antagonist as monotherapy treatment for subjects with mild-to-moderate probable Alzheimer's disease (AD). METHODS: In this 16-week, double-blind, randomized, parallel group study, 196 currently untreated subjects with mild-tomoderate AD (Mini Mental State Examination [MMSE] 16-24) received GSK239512 (n=97); or placebo (n=99) administered orally each morning. After a two-week placebo run-in period GSK239512 was up-titrated over 4 weeks in a flexible manner (10-20-40-80 microgram [µg]) followed by a 12-week Maintenance Phase. Co-primary efficacy endpoints were change from baseline in Episodic Memory and Executive Function/Working Memory composite scores from the CogState neuropsychological test battery (NTB) at Week 16. RESULTS: Compared to placebo, GSK239512 improved Episodic Memory at Week 16 (Effect Size [ES] =0.35; p=0.0495). No statistically significant differences were observed on other cognitive domains or on clinical measures including the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADASCog). GSK239512 treatment was associated with mild to moderate adverse events with headache, dizziness and events related to sleep disturbances being the most common and more pronounced in the early titration period when subjects were first being exposed to GSK239512 at the lower 10µg and 20µg doses. There were no clinically relevant changes in other safety parameters. CONCLUSION: GSK239512, at doses up to 80µg/day, improved Episodic Memory in patients with mildto- moderate AD. However, no improvements were observed on Executive Function/Working Memory or other domains of cognition. No changes were observed on any of the clinical measures included as secondary endpoints (including ADAS-Cog) indicating that GSK239512 failed to show benefit in this population. GSK239512 had an acceptable safety and tolerability profile. These findings suggest that H3 antagonists may, at most, have modest and selective effects on cognitive function in patients with mild-to-moderate AD.

Measuring anxiety as a treatment endpoint in youth with autism spectrum disorder.

Despite the high rate of anxiety in individuals with autism spectrum disorder (ASD), measuring anxiety in ASD is fraught with uncertainty. This is due, in part, to incomplete consensus on the manifestations of anxiety in this population. Autism Speaks assembled a panel of experts to conduct a systematic review of available measures for anxiety in youth with ASD. To complete the review, the panel held monthly conference calls and two face-to-face meetings over a fourteen-month period. Thirty eight published studies were reviewed and ten assessment measures were examined: four were deemed appropriate for use in clinical trials, although with conditions; three were judged to be potentially appropriate, while three were considered not useful for clinical trials assessing anxiety. Despite recent advances, additional relevant, reliable and valid outcome measures are needed to evaluate treatments for anxiety in ASD.

Clinical features of patients with treatment-emergent suicidal behavior following initiation of paroxetine therapy.

BACKGROUND: Understanding suicidal behavior is an important component of assessing suicidality in psychiatric patients. GlaxoSmithKline (GSK) conducted a meta-analysis of randomized, placebo-controlled trials to compare suicidality in adult patients treated with paroxetine vs. placebo. The goal was to identify emergent clinical characteristics of patients with definitive suicidal behavior (DSB: preparatory act, suicide attempt, completed suicide). METHODS: The dataset comprised 14,911 patients from 57 placebo-controlled paroxetine trials. Possible cases of suicidality were identified and were blindly reviewed by an expert panel, which categorized cases as suicidal or non-suicidal. DSB incidences were compared between paroxetine and placebo. Clinical narratives and case report forms for major depressive disorder (MDD) and anxiety disorder patients with DSB were reviewed. For MDD, rating scale items relating to suicidality, insomnia, agitation, and anxiety were examined. RESULTS: Overall (all indications) there were no differences between paroxetine and placebo for DSB (50/8958 [0.56%] vs. 40/5953 [0.67%], respectively; OR=1.2 [CI 0.8, 1.9]; p=0.483). However, in patients with major depressive disorder (MDD), the incidence of DSB was greater for paroxetine (11/3455 [0.32%] vs. 1/1978 [0.05%], OR=6.7 [CI 1.1, 149.4]; p=0.058). Review of the 11 paroxetine MDD cases revealed common clinical features: symptomatic improvement; younger age (18-30 years); psychosocial stressors; overdose as method; and absent/mild suicidal ideation at the visit prior to the event. There was no evidence for a consistent adverse event profile or onset of akathisia/agitation or a manic/mixed state. Anxiety disorder patients with DSB had a heterogeneous clinical picture. LIMITATIONS: Limitations to the study include the relatively small number of cases and the retrospective nature of the study. CONCLUSIONS: DSB incidence was similar between paroxetine and placebo overall, but a higher frequency of DSB was found for paroxetine in MDD patients, driven by young adults aged < or =30 years. Most MDD patients with DSB improved prior to the attempt and experienced a psychosocial stressor. Patients should receive careful monitoring for suicidality during paroxetine therapy.

Gepirone extended-release in the treatment of adult outpatients with major depressive disorder: a double-blind, randomized, placebo-controlled, parallel-group study.

OBJECTIVE: To evaluate the efficacy and tolerability of extended-release gepirone (gepirone-ER), a 5-HT(1A) agonist, versus placebo in the treatment of adult outpatients with major depressive disorder (MDD). METHOD: A double-blind, randomized, placebo-controlled, parallel-group, 8-week study was conducted from October 2003 to August 2004 in outpatients 18 to 64 years old with moderate-to-severe MDD, as defined by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR), and a baseline Hamilton Rating Scale for Depression (HAM-D(17)) total score > or = 20. Patients were titrated from 20 to 80 mg/day of gepirone-ER or placebo (most patients received gepirone-ER 60 or 80 mg/day by week 3). The primary outcome measure was baseline-to-endpoint mean change in HAM-D(17) total score. Secondary outcome measures included the 28-item version of the HAM-D, HAM-D depressed mood (item 1), Bech Six-Item Scale, Montgomery-Asberg Depression Rating Scale, and Clinical Global Impressions scale. RESULTS: Significantly greater reductions in HAM-D(17) total scores occurred in gepirone-ER-treated patients compared with placebo-treated patients by week 4 (p = .004) and continued through weeks 6 (p = .006) and 8 (p = .032). Secondary outcomes also improved significantly at multiple timepoints, including at endpoint. The most frequently reported adverse events in the gepirone-ER versus placebo groups were dizziness (45% vs. 10%), nausea (36% vs. 13%), and headache (24% vs. 16%). Dizziness occurred most frequently during initial dosing and up-titration. CONCLUSIONS: Gepirone-ER significantly reduced depression symptoms and illness severity in MDD outpatients through the end of the study and was generally well tolerated, confirming previous findings.

A pilot study of an electronic, adolescent version of the quick inventory of depressive symptomatology.

BACKGROUND: Adolescent depression assessments are time-intensive, often requiring separate interviews with an adolescent and a parent/ informant. In adults, a self-rated, interactive voice response (IVR) version of the Quick Inventory of Depressive Symptomatology (QIDS-IVR) has been shown to be reliable, valid, and sensitive to change. An adolescent version of the QIDS (QIDS-A-IVR) was created using speaker-independent voice recognition technology. An informant version, QIDS-P-IVR, collects ratings from parents or other knowledgeable adults. METHOD: The study included 27 adolescents ranging from 12 to 17 years of age, 48% of whom were female. During a single office visit, adolescents completed the QIDS-A-IVR and parents completed the QIDS-P-IVR. A clinician completed the clinician-rated adult version of the QIDS separately for adolescents (QIDS-C-A) and parents (QIDS-C-P) and the Children's Depression Rating Scale-Revised (CDRS-R). The study was conducted from October 2005 to April 2006. RESULTS: Cronbach alpha of the QIDS-A-IVR was .85. The QIDS-A-IVR correlated significantly with the QIDS-C-A (r = 0.95) and the CDRS-R (r = 0.76), both p < .01. Conversely, the correlations of the QIDS-A-IVR with the QIDS-P-IVR and the QIDS-C-P were small and nonsignificant. The QIDS-A-IVR required adolescents a mean of 6 minutes and 31 seconds to complete (SD = 41 seconds). The voice recognition technology correctly identified the adolescents' spoken words in 92% of the 483 spoken responses. The system recognized a response from all adolescents on all items. CONCLUSIONS: This study supports the reliability and validity of the QIDS-A-IVR as an adolescent depression measure. The QIDS-A-IVR may provide clinicians and researchers with a sound, technology-based method of assessing adolescent depression. Future research is needed on the informational value of parent ratings of adolescent depression.