The Experts below are selected from a list of 48 Experts worldwide ranked by ideXlab platform
Barry J. Gertz - One of the best experts on this subject based on the ideXlab platform.
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Effects of oral administration of Ibutamoren mesylate, a nonpeptide growth hormone secretagogue, on the growth hormone-insulin-like growth factor I axis in growth hormone-deficient children.
Clinical pharmacology and therapeutics, 2001Co-Authors: Ethel Codner, Fernando Cassorla, Anatoly N. Tiulpakov, M. Verónica Mericq, Alejandra Avila, Ora H. Pescovitz, Johan Svensson, Kristine Cerchio, D Krupa, Barry J. GertzAbstract:Ibutamoren mesylate (MK-0677), an orally active nonpeptide growth hormone (GH) secretagogue, stimulates GH release through a pituitary and hypothalamic receptor that is different from the GH-releasing hormone receptor. We evaluated the safety and tolerability and the GH-insulin-like growth factor (IGF) responses to two dosages of oral Ibutamoren mesylate given to children with GH deficiency for 7 to 8 days. The patients, 18 prepubertal children (15 male, 3 female) with idiopathic GH deficiency, had a chronologic age of 10.6 +/- 0.8 years (mean +/- SD), bone age of 7.4 +/- 0.7 years, growth velocity < 10th percentile for age, height < 10th percentile for age, and a maximum GH response of < or = 10 microg/L to two different GH stimulation tests. The children were assigned as follows to one of three treatment groups with Ibutamoren mesylate: 0.2 mg/kg per day for 7 days (days 1-7 or 8-14) and matching placebo for the alternate 7 days (groups I and II, respectively) or 0.8 mg/kg per day for 7 days (days 8-14, group III). On day 15 all patients received an 0.8-mg/kg dose of Ibutamoren mesylate. Patients in groups I and II were studied first to assess safety at the low dose before advancement to the high dose. Hormonal profiles were evaluated on day -1 (baseline) and day 15, and the results were expressed as the change from baseline within each group. After administration of Ibutamoren mesylate 0.8 mg/kg for 8 days (group III), the median increases (on day 15) from baseline were as follows: 3.8 microg/L (range, 0 to 34.3) for serum GH peak concentration (P = .001), 4.3 microg x h/L (range, 1.3 to 35.6) for the GH area under the concentration-time curve from time zero to 8 hours (AUC(0-8)) (P < .001), 12 microg/L (range, -4 to 116) for serum IGF-I (P = .01), and 0.4 microg/L (range, -0.9 to 1.5) for serum IGF-binding protein 3 (IGFBP-3) (P = .01). There was no change in serum prolactin, glucose, triiodothyronine, thyroxine, thyrotropin, peak serum cortisol, and insulin concentrations or 24-hour urinary free cortisol after administration of 0.8 mg/kg per day of Ibutamoren mesylate for 8 days. We conclude that short-term administration of Ibutamoren mesylate can increase GH, IGF-I, and IGFBP-3 levels in some children with GH deficiency. Thus this compound is applicable for testing its effect on growth velocity.
M L Nessly - One of the best experts on this subject based on the ideXlab platform.
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Growth hormone secretagogue MK-677: No clinical effect on AD progression in a randomized trial
Neurology, 2008Co-Authors: J J Sevigny, J M Ryan, C H Van Dyck, Y Peng, Christopher Lines, M L NesslyAbstract:Background: In animals, insulin-like growth factor-1 (IGF-1) increases clearance of β-amyloid, a pathologic hallmark of Alzheimer disease (AD), from the CNS. Serum IGF-1 level decreases with age, and shows a further decrease in AD. We examined whether the growth hormone secretagogue MK-677 (Ibutamoren mesylate), a potent inducer of IGF-1 secretion, slows the rate of progression of symptoms in patients with AD. Methods: A double-blind, multicenter study was conducted in which 563 patients with mild to moderate AD were randomized to receive MK-677 25 mg or placebo daily for 12 months. Efficacy measures were mean change from baseline at month 12 on the Clinician9s Interview Based Impression of Change with caregiver input (CIBIC-plus), the cognitive subscale of the Alzheimer9s Disease Assessment Scale (ADAS-Cog), Alzheimer9s Disease Cooperative Study-Activities of Daily Living (ADCS-ADL), and the Clinical Dementia Rating-sum of boxes (CDR-sob). Results: A total of 416 patients completed treatment and assessments at 12 months. Administration of MK-677 25 mg resulted in a 60.1% increase in serum IGF-1 levels at 6 weeks and a 72.9% increase at 12 months. In mixed-effects models that included treatment, time (month), randomization strata (baseline MMSE score ≤20 vs >20), and interaction of treatment-by-time, there were no significant differences between the treatment groups on the CIBIC-plus or the mean change from baseline scores on the ADAS-Cog, ADCS-ADL, or CDR-sob scores over 12 months. Conclusion: Despite evidence of target engagement as indicated by an increase in serum insulin-like growth factor-1, the human growth hormone secretagogue MK-677 25 mg was ineffective at slowing the rate of progression of Alzheimer disease.
Ethel Codner - One of the best experts on this subject based on the ideXlab platform.
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Effects of oral administration of Ibutamoren mesylate, a nonpeptide growth hormone secretagogue, on the growth hormone-insulin-like growth factor I axis in growth hormone-deficient children.
Clinical pharmacology and therapeutics, 2001Co-Authors: Ethel Codner, Fernando Cassorla, Anatoly N. Tiulpakov, M. Verónica Mericq, Alejandra Avila, Ora H. Pescovitz, Johan Svensson, Kristine Cerchio, D Krupa, Barry J. GertzAbstract:Ibutamoren mesylate (MK-0677), an orally active nonpeptide growth hormone (GH) secretagogue, stimulates GH release through a pituitary and hypothalamic receptor that is different from the GH-releasing hormone receptor. We evaluated the safety and tolerability and the GH-insulin-like growth factor (IGF) responses to two dosages of oral Ibutamoren mesylate given to children with GH deficiency for 7 to 8 days. The patients, 18 prepubertal children (15 male, 3 female) with idiopathic GH deficiency, had a chronologic age of 10.6 +/- 0.8 years (mean +/- SD), bone age of 7.4 +/- 0.7 years, growth velocity < 10th percentile for age, height < 10th percentile for age, and a maximum GH response of < or = 10 microg/L to two different GH stimulation tests. The children were assigned as follows to one of three treatment groups with Ibutamoren mesylate: 0.2 mg/kg per day for 7 days (days 1-7 or 8-14) and matching placebo for the alternate 7 days (groups I and II, respectively) or 0.8 mg/kg per day for 7 days (days 8-14, group III). On day 15 all patients received an 0.8-mg/kg dose of Ibutamoren mesylate. Patients in groups I and II were studied first to assess safety at the low dose before advancement to the high dose. Hormonal profiles were evaluated on day -1 (baseline) and day 15, and the results were expressed as the change from baseline within each group. After administration of Ibutamoren mesylate 0.8 mg/kg for 8 days (group III), the median increases (on day 15) from baseline were as follows: 3.8 microg/L (range, 0 to 34.3) for serum GH peak concentration (P = .001), 4.3 microg x h/L (range, 1.3 to 35.6) for the GH area under the concentration-time curve from time zero to 8 hours (AUC(0-8)) (P < .001), 12 microg/L (range, -4 to 116) for serum IGF-I (P = .01), and 0.4 microg/L (range, -0.9 to 1.5) for serum IGF-binding protein 3 (IGFBP-3) (P = .01). There was no change in serum prolactin, glucose, triiodothyronine, thyroxine, thyrotropin, peak serum cortisol, and insulin concentrations or 24-hour urinary free cortisol after administration of 0.8 mg/kg per day of Ibutamoren mesylate for 8 days. We conclude that short-term administration of Ibutamoren mesylate can increase GH, IGF-I, and IGFBP-3 levels in some children with GH deficiency. Thus this compound is applicable for testing its effect on growth velocity.
Mario Thevis - One of the best experts on this subject based on the ideXlab platform.
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An in vitro assay approach to investigate the potential impact of different doping agents on the steroid profile.
Drug testing and analysis, 2020Co-Authors: Thomas Piper, Sonja Heimbach, Martin Adamczewski, Mario ThevisAbstract:The steroid profile, that is, the urinary concentrations and concentration ratios of selected steroids, is used in sports drug testing to detect the misuse of endogenous steroids such as testosterone. Since several years, not only population-based thresholds are applied but also the steroid profile is monitored via the Athlete Biological Passport whereby the individual reference ranges derived from multiple test results of the same athlete are compared to population-based thresholds. In order to maintain a high probative force of the passport, samples collected or analyzed under suboptimal conditions should not be included in the longitudinal review. This applies to biologically affected or degraded samples and to samples excluded owing to the presence of other substances potentially (or evidently) altering the steroid profile. Nineteen different doping agents comprising anabolic steroids, selective androgen receptor modulators, selective estrogen receptor modulators, Ibutamoren, and tibolone were investigated for their effect on the steroid profile using an androgen receptor activation test, an androgen receptor binding assay, an aromatase assay, and a steroidogenesis assay. The in vitro tests were coupled with well-established liquid chromatography/mass spectrometry-based analytical approaches and for a subset of steroidal analytes by gas chromatography/mass spectrometry. The variety of tests employed should produce a comprehensive data set to better understand how a compound under investigation may impact the steroid profile. Although our data set may allow an estimate of whether or not a substance will have an impact on the overall steroid metabolism, predicting which parameter in particular may be influenced remains difficult.
J J Sevigny - One of the best experts on this subject based on the ideXlab platform.
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Growth hormone secretagogue MK-677: No clinical effect on AD progression in a randomized trial
Neurology, 2008Co-Authors: J J Sevigny, J M Ryan, C H Van Dyck, Y Peng, Christopher Lines, M L NesslyAbstract:Background: In animals, insulin-like growth factor-1 (IGF-1) increases clearance of β-amyloid, a pathologic hallmark of Alzheimer disease (AD), from the CNS. Serum IGF-1 level decreases with age, and shows a further decrease in AD. We examined whether the growth hormone secretagogue MK-677 (Ibutamoren mesylate), a potent inducer of IGF-1 secretion, slows the rate of progression of symptoms in patients with AD. Methods: A double-blind, multicenter study was conducted in which 563 patients with mild to moderate AD were randomized to receive MK-677 25 mg or placebo daily for 12 months. Efficacy measures were mean change from baseline at month 12 on the Clinician9s Interview Based Impression of Change with caregiver input (CIBIC-plus), the cognitive subscale of the Alzheimer9s Disease Assessment Scale (ADAS-Cog), Alzheimer9s Disease Cooperative Study-Activities of Daily Living (ADCS-ADL), and the Clinical Dementia Rating-sum of boxes (CDR-sob). Results: A total of 416 patients completed treatment and assessments at 12 months. Administration of MK-677 25 mg resulted in a 60.1% increase in serum IGF-1 levels at 6 weeks and a 72.9% increase at 12 months. In mixed-effects models that included treatment, time (month), randomization strata (baseline MMSE score ≤20 vs >20), and interaction of treatment-by-time, there were no significant differences between the treatment groups on the CIBIC-plus or the mean change from baseline scores on the ADAS-Cog, ADCS-ADL, or CDR-sob scores over 12 months. Conclusion: Despite evidence of target engagement as indicated by an increase in serum insulin-like growth factor-1, the human growth hormone secretagogue MK-677 25 mg was ineffective at slowing the rate of progression of Alzheimer disease.
