RESUMEN
BACKGROUND: Adrenal insufficiency in patients with classic 21-hydroxylase deficiency congenital adrenal hyperplasia (CAH) is treated with glucocorticoid replacement therapy. Control of adrenal-derived androgen excess usually requires supraphysiologic glucocorticoid dosing, which predisposes patients to glucocorticoid-related complications. Crinecerfont, an oral corticotropin-releasing factor type 1 receptor antagonist, lowered androstenedione levels in phase 2 trials involving patients with CAH. METHODS: In this phase 3 trial, we randomly assigned adults with CAH in a 2:1 ratio to receive crinecerfont or placebo for 24 weeks. Glucocorticoid treatment was maintained at a stable level for 4 weeks to evaluate androstenedione values, followed by glucocorticoid dose reduction and optimization over 20 weeks to achieve the lowest glucocorticoid dose that maintained androstenedione control (≤120% of the baseline value or within the reference range). The primary efficacy end point was the percent change in the daily glucocorticoid dose from baseline to week 24 with maintenance of androstenedione control. RESULTS: All 182 patients who underwent randomization (122 to the crinecerfont group and 60 to the placebo group) were included in the 24-week analysis, with imputation of missing values; 176 patients (97%) remained in the trial at week 24. The mean glucocorticoid dose at baseline was 17.6 mg per square meter of body-surface area per day of hydrocortisone equivalents; the mean androstenedione level was elevated at 620 ng per deciliter. At week 24, the change in the glucocorticoid dose (with androstenedione control) was -27.3% in the crinecerfont group and -10.3% in the placebo group (least-squares mean difference, -17.0 percentage points; P<0.001). A physiologic glucocorticoid dose (with androstenedione control) was reported in 63% of the patients in the crinecerfont group and in 18% in the placebo group (P<0.001). At week 4, androstenedione levels decreased with crinecerfont (-299 ng per deciliter) but increased with placebo (45.5 ng per deciliter) (least-squares mean difference, -345 ng per deciliter; P<0.001). Fatigue and headache were the most common adverse events in the two trial groups. CONCLUSIONS: Among patients with CAH, the use of crinecerfont resulted in a greater decrease from baseline in the mean daily glucocorticoid dose, including a reduction to the physiologic range, than placebo following evaluation of adrenal androgen levels. (Funded by Neurocrine Biosciences; CAHtalyst ClinicalTrials.gov number, NCT04490915.).
Asunto(s)
Hiperplasia Suprarrenal Congénita , Aminas , Androstenodiona , Tiazoles , Adulto , Femenino , Humanos , Masculino , Adulto Joven , Hiperplasia Suprarrenal Congénita/sangre , Hiperplasia Suprarrenal Congénita/complicaciones , Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Androstenodiona/sangre , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Glucocorticoides/administración & dosificación , Glucocorticoides/efectos adversos , Hidrocortisona/sangre , Aminas/administración & dosificación , Aminas/efectos adversos , Tiazoles/administración & dosificación , Tiazoles/efectos adversos , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Quimioterapia Combinada/efectos adversos , Quimioterapia Combinada/métodos , Fatiga/inducido químicamente , Fatiga/epidemiología , Cefalea/inducido químicamente , Cefalea/epidemiologíaRESUMEN
BACKGROUND: Children with classic congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency require treatment with glucocorticoids, usually at supraphysiologic doses, to address cortisol insufficiency and reduce excess adrenal androgens. However, such treatment confers a predisposition to glucocorticoid-related complications. In 2-week phase 2 trials, patients with CAH who received crinecerfont, a new oral corticotropin-releasing factor type 1 receptor antagonist, had decreases in androstenedione levels. METHODS: In this phase 3, multinational, randomized trial, we assigned pediatric participants with CAH, in a 2:1 ratio, to receive crinecerfont or placebo for 28 weeks. A stable glucocorticoid dose was maintained for 4 weeks, and the dose was then adjusted to a target of 8.0 to 10.0 mg per square meter of body-surface area per day (hydrocortisone dose equivalents), provided that the androstenedione level was controlled (≤120% of the baseline level or within the reference range). The primary efficacy end point was the change in the androstenedione level from baseline to week 4. A key secondary end point was the percent change in the glucocorticoid dose from baseline to week 28 while androstenedione control was maintained. RESULTS: A total of 103 participants underwent randomization, of whom 69 were assigned to crinecerfont and 34 to placebo; 100 (97%) remained in the trial at 28 weeks. At baseline, the mean glucocorticoid dose was 16.4 mg per square meter per day, and the mean androstenedione level was 431 ng per deciliter (15.0 nmol/liter). At week 4, androstenedione was substantially reduced in the crinecerfont group (-197 ng per deciliter [-6.9 nmol/liter]) but increased in the placebo group (71 ng per deciliter [2.5 nmol/liter]) (least-squares mean difference [LSMD], -268 ng per deciliter [-9.3 nmol/liter]; P<0.001); the observed mean androstenedione value, obtained before the morning glucocorticoid dose, was 208 ng per deciliter (7.3 nmol/liter) in the crinecerfont group, as compared with 545 ng per deciliter (19.0 nmol/liter) in the placebo group. At week 28, the mean glucocorticoid dose had decreased (while androstenedione control was maintained) by 18.0% with crinecerfont but increased by 5.6% with placebo (LSMD, -23.5 percentage points; P<0.001). Headache, pyrexia, and vomiting were the most common adverse events. CONCLUSIONS: In this phase 3 trial, crinecerfont was superior to placebo in reducing elevated androstenedione levels in pediatric participants with CAH and was also associated with a decrease in the glucocorticoid dose from supraphysiologic to physiologic levels while androstenedione control was maintained. (Funded by Neurocrine Biosciences; CAHtalyst Pediatric ClinicalTrials.gov number, NCT04806451.).
Asunto(s)
Hiperplasia Suprarrenal Congénita , Aminas , Androstenodiona , Glucocorticoides , Tiazoles , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Hiperplasia Suprarrenal Congénita/sangre , Hiperplasia Suprarrenal Congénita/complicaciones , Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Androstenodiona/sangre , Método Doble Ciego , Glucocorticoides/administración & dosificación , Glucocorticoides/efectos adversos , Hidrocortisona , Aminas/administración & dosificación , Aminas/efectos adversos , Tiazoles/administración & dosificación , Tiazoles/efectos adversos , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Cefalea/inducido químicamente , Cefalea/epidemiología , Fiebre/inducido químicamente , Fiebre/epidemiología , Vómitos/inducido químicamente , Vómitos/epidemiologíaRESUMEN
BACKGROUND: Tardive dyskinesia (TD), a movement disorder in which patients experience abnormal involuntary movements, can have profound negative impacts on physical, cognitive, and psychosocial functioning. The Abnormal Involuntary Movement Scale (AIMS), a clinician-rated outcome, is considered the gold standard for evaluating treatment efficacy in TD clinical trials. However, it provides little information about the impacts of uncontrolled movements from a patient perspective and can be cumbersome to administer in clinical settings. The Tardive Dyskinesia Impact Scale (TDIS) was developed as a patient-reported outcome measure to fulfill the need for a disease-specific impact assessment in TD. The objective of the present study was to develop and evaluate the psychometric properties of the TDIS to determine whether it is fit-for-purpose to measure TD impact. METHODS: Data from qualitative studies and phase 3 trials of a VMAT2 inhibitor for the treatment of TD (KINECT3 and KINECT4) were used to determine the psychometric properties of the TDIS. Qualitative research included concept elicitation and cognitive debriefing interviews with TD patients and their caregivers in order to assess how well the TDIS captured key domains of TD impact. Quantitative analyses to examine the psychometric properties of the TDIS included assessing construct validity (factor structure, known groups, and predictive validity) and responsiveness to change. RESULTS: Qualitative results showed that the TDIS captures the key TD impacts reported by patients and caregivers and that the TDIS was interpreted as intended and relevant to patients' experiences. Quantitative results found evidence of 2 underlying domains of the TDIS: physical and socioemotional (Comparative Fit Index > 0.9). Known groups and predictive validity indicated that, compared with the AIMS, the TDIS captures unique content (correlation between AIMS and TDIS = 0.2-0.28). The TDIS showed responsiveness to change in treatment, with TDIS scores improving over 48 weeks in the 2 phase 3 trials. CONCLUSIONS: The TDIS captures relevant information about the impact of TD and is easily administered in a clinician's office or patient's home. It may be used longitudinally to show changes in TD burden over time. The TDIS complements the AIMS; using these assessments together provides a more holistic assessment of TD.
Tardive dyskinesia is a condition where people have uncontrollable movements because of taking certain medications for a long time. It is still poorly understood how these uncontrollable movements affect a person's everyday activities. We created a questionnaire called the Tardive Dyskinesia Impact Scale (TDIS). The TDIS is a questionnaire where people with tardive dyskinesia rate how their symptoms affect daily activities such as speaking and walking. People can also rate how the uncontrollable movements make them feel. We used specific tests called psychometric tests to see if the TDIS measures the correct information and if the information is reliable. Findings from this study show that the TDIS is a good way to measure how a person's uncontrollable movements affect everyday activities. The results also show that when people take medicine to help with their symptoms, their TDIS scores are better. When patients stopped taking the medicine, their symptoms were worse, and their TDIS score was worse. The TDIS can help people explain how their uncontrollable movements affect their daily life. This can then help their doctors understand the person's condition better.
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Discinesias , Trastornos del Movimiento , Discinesia Tardía , Humanos , Discinesia Tardía/diagnóstico , Psicometría , Medición de Resultados Informados por el PacienteRESUMEN
CONTEXT: Crinecerfont, a corticotropin-releasing factor type 1 receptor antagonist, has been shown to reduce elevated adrenal androgens and precursors in adults with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21OHD), a rare autosomal recessive disorder characterized by cortisol deficiency and androgen excess due to elevated adrenocorticotropin. OBJECTIVE: To evaluate the safety, tolerability, and efficacy of crinecerfont in adolescents with 21OHD CAH. METHODS: This was an open-label, phase 2 study (NCT04045145) at 4 centers in the United States. Participants were males and females, 14 to 17 years of age, with classic 21OHD CAH. Crinecerfont was administered orally (50 mg twice daily) for 14 consecutive days with morning and evening meals. The main outcomes were change from baseline to day 14 in circulating concentrations of ACTH, 17-hydroxyprogesterone (17OHP), androstenedione, and testosterone. RESULTS: 8 participants (3 males, 5 females) were enrolled; median age was 15 years and 88% were Caucasian/White. After 14 days of crinecerfont, median percent reductions from baseline to day 14 were as follows: ACTH, -57%; 17OHP, -69%; and androstenedione, -58%. In female participants, 60% (3/5) had ≥50% reduction from baseline in testosterone. CONCLUSION: Adolescents with classic 21OHD CAH had substantial reductions in adrenal androgens and androgen precursors after 14 days of oral crinecerfont administration. These results are consistent with a study of crinecerfont in adults with classic 21OHD CAH.
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Hiperplasia Suprarrenal Congénita , Andrógenos , Masculino , Adulto , Humanos , Femenino , Adolescente , Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Androstenodiona , 17-alfa-Hidroxiprogesterona , Testosterona , Hormona AdrenocorticotrópicaRESUMEN
The pharmacokinetic (PK) profile of budesonide oral suspension (BOS) was evaluated during a phase 2, randomized, double-blind, placebo-controlled, dose-ranging study in pediatric patients with eosinophilic esophagitis (EoE) (MPI 101-01/NCT00762073). Non-compartmental methods were used to calculate PK parameters in 37 patients after receiving morning doses of BOS, with volume and dose adjusted for age (low dose: 0.35 or 0.5 mg; high dose: 1.4 or 2.0 mg [2-9 or 10-18 years old, respectively]). Relationships between apparent oral clearance and volume of distribution, and bodyweight and body mass index were also evaluated. Budesonide systemic exposure increased with BOS dose. After oral administration, time to maximum plasma budesonide concentration occurred ~1 hour post dose and the half-life of budesonide was 3.3-3.5 hours. PK parameters were similar between age groups for low- and high-dose BOS, indicating that volume and dose adjustments for age were appropriate for pediatric patients with EoE. BOS was well tolerated.
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Budesonida , Esofagitis Eosinofílica , Administración Oral , Adolescente , Budesonida/uso terapéutico , Niño , Método Doble Ciego , Esofagitis Eosinofílica/tratamiento farmacológico , Glucocorticoides , Humanos , Suspensiones , Resultado del TratamientoRESUMEN
CONTEXT: Classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency (21OHD) is characterized by impaired cortisol synthesis and excess androgen production. Corticotropin-releasing factor type 1 receptor (CRF1R) antagonism may decrease adrenal androgen production. OBJECTIVE: This work aimed to evaluate the safety, tolerability, and efficacy of crinecerfont (NBI-74788), a selective CRF1R antagonist, in 21OHD. METHODS: This open-label, phase 2 study, with sequential cohort design (NCT03525886), took place in 6 centers in the United States. Participants included men and women, aged 18 to 50 years, with 21OHD. Interventions included 4 crinecerfont regimens, each administered orally for 14 consecutive days: 50 or 100 mg once daily at bedtime (cohorts 1 and 2, respectively); 100 mg once daily in the evening (cohort 3); and 100 mg twice daily (cohort 4). Participants could enroll in more than 1 cohort. Main outcomes included changes from baseline to day 14 in adrenocorticotropin (ACTH), 17-hydroxyprogesterone (17OHP), androstenedione, and testosterone. RESULTS: Eighteen participants (11 women, 7 men) were enrolled: cohort 1 (nâ =â 8), cohort 2 (nâ =â 7), cohort 3 (nâ =â 8), cohort 4 (nâ =â 8). Mean age was 31 years; 94% were White. Median percent reductions were more than 60% for ACTH (-66%), 17OHP (-64%), and androstenedione (-64%) with crinecerfont 100 mg twice a day. In female participants, 73% (8/11) had a 50% or greater reduction in testosterone levels; male participants had median 26% to 65% decreases in androstenedione/testosterone ratios. CONCLUSION: Crinecerfont treatment for 14 days lowered ACTH and afforded clinically meaningful reductions of elevated 17OHP, androstenedione, testosterone (women), or androstenedione/testosterone ratio (men) in adults with 21OHD. Longer-term studies are required to evaluate the effects of crinecerfont on clinical end points of disordered steroidogenesis and glucocorticoid exposure in patients with 21OHD.
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Hiperplasia Suprarrenal Congénita , Compuestos de Azabiciclo , Oxadiazoles , Receptores de Hormona Liberadora de Corticotropina , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , 17-alfa-Hidroxiprogesterona/sangre , Administración Oral , Hiperplasia Suprarrenal Congénita/sangre , Hiperplasia Suprarrenal Congénita/diagnóstico , Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Hormona Adrenocorticotrópica/sangre , Androstenodiona/sangre , Compuestos de Azabiciclo/administración & dosificación , Biomarcadores/sangre , Relación Dosis-Respuesta a Droga , Oxadiazoles/administración & dosificación , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , Testosterona/sangre , Resultado del TratamientoRESUMEN
Introduction: Significant need exists for effective, well-tolerated pharmacologic treatments for Tourette syndrome (TS). Medications that inhibit vesicular monoamine transporters (i.e. VMAT2 inhibitors) downregulate presynaptic packaging and release of dopamine into the neuronal synapse and are effective in treating hyperkinetic movement disorders such as Huntington's chorea and tardive dyskinesia (TD); thus, they may be useful in treating TS.Areas covered: This review describes the clinical program evaluating the safety and efficacy of valbenazine in the treatment of involuntary tics associated with TS in adult and pediatric subjects. While there was a trend in the 6 completed trials toward greater improvement in valbenazine-treated versus placebo subjects on the primary efficacy endpoint (Yale Global Tic Severity Scale Total Tic Score), this difference did not reach statistical significance. Valbenazine was generally well-tolerated in the studies, and treatment-emergent adverse events were consistent with valbenazine studies in TD.Expert opinion: Due to the failure to meet the primary endpoint in these trials, further investigation of valbenazine for TS is unlikely. Given the need for safe and effective TS therapies and the key role of VMAT2 in modulating dopaminergic activity, it is reasonable for future studies to investigate other VMAT2 inhibitors as potential treatments for TS.
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Antipsicóticos , Tics , Síndrome de Tourette , Adulto , Antipsicóticos/uso terapéutico , Niño , Humanos , Tetrabenazina/análogos & derivados , Tetrabenazina/uso terapéutico , Tics/tratamiento farmacológico , Síndrome de Tourette/tratamiento farmacológico , Valina/análogos & derivados , Proteínas de Transporte Vesicular de MonoaminasRESUMEN
CONTEXT: Treatment of 21-hydroxylase deficiency (21OHD) is difficult to optimize. Normalization of excessive ACTH and adrenal steroid production commonly requires supraphysiologic doses of glucocorticoids. OBJECTIVES: We evaluated the safety and tolerability of the selective corticotropin releasing factor type 1 (CRF1) receptor antagonist NBI-77860 in women with classic 21OHD and tested the hypothesis that CRF1 receptor blockade decreases early-morning ACTH and 17α-hydroxyprogesterone (17OHP) in these patients. PARTICIPANTS: The study enrolled eight classic 21OHD females, ages 18-58 years, seen at a single tertiary referral university setting. DESIGN: This was a phase Ib, single-blind, placebo-controlled, fixed-sequence, single-dose trial. During three treatment periods separated by 3-week washout intervals, patients sequentially received placebo, NBI-77860 300 mg, and NBI-77860 600 mg at 10 pm; glucocorticoid therapy was withheld for 20 hours. We evaluated ACTH, 17OHP, androstenedione, and testosterone as well as NBI-77860 pharmacokinetics over 24 hours. RESULTS: Dose-dependent reductions of ACTH and/or 17OHP were observed in six of eight subjects. Relative to placebo, NBI-77860 led to an ACTH and 17OHP reduction by a mean of 43% and 0.7% for the 300 mg dose, respectively, and by 41% and 27% for the 600 mg dose, respectively. Both NBI-77860 doses were well tolerated. CONCLUSION: The meaningful reductions in ACTH and 17OHP following NBI-77860 dosing in 21OHD patients demonstrate target engagement and proof of principle in this disorder. These promising data provide a rationale for additional investigations of CRF1 receptor antagonists added to physiologic doses of hydrocortisone and fludrocortisone acetate for the treatment of classic 21OHD.
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Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Compuestos de Azabiciclo/administración & dosificación , Oxadiazoles/administración & dosificación , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidores , 17-alfa-Hidroxiprogesterona/sangre , Hiperplasia Suprarrenal Congénita/metabolismo , Hormona Adrenocorticotrópica/sangre , Adulto , Compuestos de Azabiciclo/efectos adversos , Compuestos de Azabiciclo/farmacocinética , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Persona de Mediana Edad , Oxadiazoles/efectos adversos , Oxadiazoles/farmacocinética , Factores de Tiempo , Adulto JovenRESUMEN
AIMS: To evaluate the pharmacokinetics (PK) of five H(1) receptor antagonists in human volunteers after a single oral and intravenous (i.v.) microdose (0.1 mg). METHODS: Five H(1) receptor antagonists, namely NBI-1, NBI-2, NBI-3, NBI-4 and diphenhydramine, were administered to human volunteers as a single 0.1-mg oral and i.v. dose. Blood samples were collected up to 48 h, and the parent compound in the plasma extract was quantified by high-performance liquid chromatography and accelerator mass spectroscopy. RESULTS: The median clearance (CL), apparent volume of distribution (V(d)) and apparent terminal elimination half-life (t(1/2)) of diphenhydramine after an i.v. microdose were 24.7 l h(-1), 302 l and 9.3 h, and the oral C(max) and AUC(0-infinity) were 0.195 ng ml(-1) and 1.52 ng h ml(-1), respectively. These data were consistent with previously published diphenhydramine data at 500 times the microdose. The rank order of oral bioavailability of the five compounds was as follows: NBI-2 > NBI-1 > NBI-3 > diphenhydramine > NBI-4, whereas the rank order for CL was NBI-4 > diphenhydramine > NBI-1 > NBI-3 > NBI-2. CONCLUSIONS: Human microdosing provided estimates of clinical PK of four structurally related compounds, which were deemed useful for compound selection.
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Antagonistas de los Receptores Histamínicos H1/farmacocinética , Administración Oral , Adulto , Cromatografía Líquida de Alta Presión , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Antagonistas de los Receptores Histamínicos H1/administración & dosificación , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
OBJECTIVE: To assess the effects of post-bedtime dosing with indiplon on next-day function in adults and the elderly. RESEARCH DESIGN AND METHODS: Two randomized, double-blind, placebo-controlled crossover studies were conducted in two groups of healthy volunteers: an adult study (18-45 years) and an elderly study (65-80 years). In adults, a single post-bedtime dose of indiplon 10 mg and 20 mg was compared to placebo, with zolpidem 10 mg and zopiclone 7.5 mg included as controls. In the elderly, a single post-bedtime dose of indiplon 5 mg and 10 mg was compared to placebo, with zopiclone 3.75 mg included as a control. Next-day residual effects were evaluated in the morning at 4 and 6 h post-dose in adults, and 4, 6, and 8 h in the elderly, by a Visual Analog Scale of sleepiness (VAS-sleepiness), Digit Symbol Substitution Test (DSST), and the Symbol Copying Test (SCT). RESULTS: In adults, there were no statistically significant differences between indiplon and placebo on the VAS-sleepiness, DSST, or SCT at any time-point for either dose. In contrast, a significant increase versus placebo in VAS-sleepiness was observed for both zopiclone (at 4 and 6 h post-dose; p < 0.0001 and p = 0.002, respectively) and zolpidem (at 4 h post-dose; p = 0.042). In the elderly, there were no statistically significant differences between indiplon 5 mg and placebo on the VAS-sleepiness, DSST, or SCT at any time-point. DSST was significantly reduced for indiplon 10 mg versus placebo at 4 h only (p = 0.022), compared with a significant reduction in DSST for zopiclone at both 4 and 8 h post-dose (p = 0.002 and p = 0.003, respectively). In adults, the overall incidence of adverse events was higher on zopiclone compared to indiplon, zolpidem, and placebo. In the elderly, the incidence of adverse events was similar for indiplon, zopiclone, and placebo. Potential limitations of the current study include recruitment of healthy volunteers and the use of a limited pharmacodynamic battery. CONCLUSIONS: Indiplon, at doses of 10 mg in adults and 5 mg in the elderly, was not associated with next day residual sedation or impairment in simple cognitive and psychomotor tasks when administered during the night 4 h prior to awakening.
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Benzodiazepinas/administración & dosificación , Benzodiazepinas/efectos adversos , Hipnóticos y Sedantes/administración & dosificación , Hipnóticos y Sedantes/efectos adversos , Trastornos del Inicio y del Mantenimiento del Sueño/tratamiento farmacológico , Tiofenos/administración & dosificación , Tiofenos/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Compuestos de Azabiciclo/administración & dosificación , Compuestos de Azabiciclo/efectos adversos , Estudios Cruzados , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Piperazinas/administración & dosificación , Piperazinas/efectos adversos , Pruebas Psicológicas , Psicometría , Piridinas/administración & dosificación , Piridinas/efectos adversos , Valores de Referencia , Factores de Tiempo , ZolpidemRESUMEN
BACKGROUND: Many of the symptoms of attention-deficit/hyperactivity disorder (ADHD) have been attributed to deficits in behavioral inhibition mediated by the frontostriatal system. The ability to suppress unwanted saccadic eye movements is mediated by prefrontal cortex-basal ganglia circuitry and thus constitutes a useful measure of inhibitory ability. METHODS: To evaluate the functional integrity of this circuitry in ADHD, adult ADHD subjects unmedicated for at least 48 hours and normal comparison adults were studied by means of a comprehensive battery of ocular motor paradigms. RESULTS: On a prosaccade task, in which subjects were required to generate saccades toward a peripheral visual target after a short stimulus-free interval, ADHD subjects generated significantly more of anticipatory (premature) saccades (reaction time <90 msec) and of saccades toward the target on catch trials, in which they were supposed to inhibit eye movements. On the antisaccade task, in which they were required to inhibit gazing toward the target while moving their eyes in the opposite direction, ADHD subjects made significantly more directional errors than normal adults. The performance of ADHD adults was consistent with deficits in saccadic inhibition. CONCLUSIONS: Given the recent evidence for the interdependence between the brain systems mediating visual attention and ocular motor behavior, these findings support the notion that deficits in inhibitory mechanisms might underlie the inattention characteristic of ADHD. These results also implicate abnormalities in prefrontal cortex-basal ganglia circuitry in ADHD.