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PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261451
Author(s):  
Daisuke Ishii ◽  
Michiharu Kageyama ◽  
Shin Umeda

Autism spectrum disorder (ASD) is a neurodevelopmental disorder associated with deficits in social interactions/communication. Despite the large number of ASD patients, there is no drug approved to treat its core symptoms. Recently, Syntocinon (oxytocin nasal spray) has been reported to have a therapeutic effect on ASD. However, the disadvantage of Syntocinon for ASD treatment is that 6 puffs/administration are required to achieve the effective pharmacological dose. Furthermore, there are no published reports evaluating the cerebral distribution profile of oxytocin after intranasal administration. TTA-121 is a newly developed intranasal oxytocin formulation with high bioavailability produced by optimizing the physicochemical properties. In this study, we prepared the same formula as Syntocinon as the control formulation (CF), and the cerebral and extracerebral distribution of oxytocin in rabbits after single intranasal administration of 3H-labeled oxytocin formulations—[3H]TTA-121 and [3H]CF were examined and compared. The area under the concentration-time curve to the time of the last quantifiable concentration (AUCt) in the whole brain was 3.6-fold higher in the [3H]TTA-121 group than in the [3H]CF group, indicating increased delivery of radioactivity to the brain by TTA-121 than by CF. Since the distribution profiles showed no notable differences in radioactivity between the olfactory bulb and trigeminal nerve, intranasally-administered oxytocin was probably transferred to the brain via both pathways. The results also showed an increase in radioactivity in the prefrontal area and the precuneus, which are probable sites of pharmacological action as shown in clinical studies using functional magnetic resonance imaging (fMRI), confirming that intranasally-administered oxytocin could reach these tissues.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Masanari Shiramoto ◽  
Tatsuya Yoshihara ◽  
Wolfgang Schmider ◽  
Hiroki Takagi ◽  
Irene Nowotny ◽  
...  

AbstractThis study compared the pharmacokinetic and glucodynamic profiles of biosimilar SAR341402 insulin aspart to Japan-approved insulin aspart (NovoRapid) in healthy Japanese males. In this single-center, randomized, double-blind, single-dose, two-period, crossover study, subjects received 0.3 U/kg of SAR341402 or NovoRapid before undergoing a 10 h euglycemic clamp procedure. Plasma insulin aspart concentrations and blood glucose levels were measured, and glucose infusion rates (GIRs) were assessed. Primary endpoints were maximum plasma insulin aspart concentration (INS-Cmax), area under the plasma insulin concentration–time curve to the last quantifiable concentration (INS-AUClast), area under the GIR–time curve during the clamp (GIR-AUC0–10 h), and maximum GIR (GIRmax). Forty subjects were randomized with 39 completing both treatment periods. Pharmacokinetic exposure showed a mean ratio between products of 1.00 (90% confidence interval [CI] 0.94–1.05) for INS-Cmax and 1.02 (90% CI 1.00–1.04) for INS-AUClast. Glucodynamic activity showed a mean ratio between products of 1.00 (95% CI 0.93–1.06) for GIR-AUC0–10 h and 1.01 (95% CI 0.95–1.08) for GIRmax. The 90% CIs for pairwise treatment ratios were within the predefined equivalence range of 0.80–1.25. Both treatments were well tolerated. We concluded that similar pharmacokinetic exposure and glucodynamic potency were shown for SAR341402 and NovoRapid in healthy Japanese males.


2021 ◽  
Vol 12 ◽  
Author(s):  
Lei Gao ◽  
Qingmei Li ◽  
Hong Zhang ◽  
Min Wu ◽  
Min Fang ◽  
...  

Objective: To evaluate the tolerance, variability, and pharmacokinetics (PK) of QX001S, a biosimilar for ustekinumab, in healthy Chinese men.Methods: One hundred and seventy-eight healthy men were recruited in this randomized, double-blind, single-dose, two-arm, parallel study, and received 45 mg of QX001S or ustekinumab in a single subcutaneous injection. PK, immunogenicity, and tolerance were evaluated in all participants for a period of 113°days.Results: The similarity between the two drugs was determined by comparing the baseline characteristics for each drug. The PK parameters were similar in the two groups: QX001S (n = 89) and ustekinumab (n = 88). The 90% confidence intervals (CIs) for the geometric mean ratio (GMR) of QX001S to the reference (ustekinumab) for the maximum observable serum concentration (Cmax), area under the curve (AUC) from zero to the final quantifiable concentration (AUC0–t), and AUC from zero to infinity (AUC0–∞) were 100.90–118.68%, 98.71–115.26%, and 98.49–115.81%, respectively, which were within the predefined bioequivalence limit of 80.00–125.00%. High inter-subject variability (ranging from 32.0 to 33.5%) was observed. A total of 17 participants (19.1%) in the QX001S group and 36 (40.9%) in the ustekinumab group developed anti-drug antibodies (ADA) after administration. Nevertheless, the ADA did not affect the outcomes of the bioequivalence tests. Adverse reactions were recorded in 38 individuals injected with QX001S and 37 injected with ustekinumab. The most common adverse reactions were upper respiratory infection and elevated alanine aminotransferase.Conclusions: Our study ratified pharmacokinetic biosimilarity between QX001 S and ustekinumab, with high variability between subjects.


CNS Spectrums ◽  
2019 ◽  
Vol 24 (1) ◽  
pp. 216-216
Author(s):  
Steve Caras ◽  
Terrilyn Sharpe

AbstractStudy ObjectivesWe compared the bioavailability of racemic amphetamine (d-amphetamine and l-amphetamine) from a manipulation-resistant immediate-release (IR) amphetamine sulfate capsule (AR19) versus amphetamine sulfate IR tablets (reference).MethodIn this open-label, randomized, two-period, two-treatment, two-sequence, crossover study, 36 healthy volunteers aged 18–45 received a single dose (20-mg capsule) of AR19 in one period and a single dose (2 x 10-mg tablets) of reference in another period, after a 10-hour overnight fast. Each drug administration was separated by a washout period of at least 6days. Bioequivalence for d- and l-amphetamine was assessed using time to peak concentration (Tmax), peak concentration in plasma (Cmax), and area under the plasma concentration–time curve from time-zero to the time of the last quantifiable concentration (AUClast) and extrapolated to infinity (AUCinf).ResultsAll 36 volunteers completed both treatment sequences. Mean (standard deviation; SD) Tmax for d- and l-amphetamine was similar for AR19 (2.84[1.05]; 3.05[1.22], respectively) and reference (2.52[0.75]; 2.75[1.00], respectively). The geometric least-squares mean ratios and 90% confidence intervals were within the boundary of 80%–125% for bioequivalence for Cmax (d-amphetamine, 98.35% [96.12–100.64]; l-amphetamine, 98.82% [96.42–101.28]), AUClast (d-amphetamine, 99.45% [96.92–102.05]; l-amphetamine, 99.29% [96.55–102.10]), and AUCinf (d-amphetamine, 99.50%[96.77–102.30]; l-amphetamine, 99.23% [96.06–102.50]). A total of 13 mild adverse events were reported by 7 volunteers (AEs; AR19, n=5; reference, n=8). No serious AEs were reported.ConclusionAR19 was well tolerated and was bioequivalent to reference when administered as a 20-mg dose in healthy volunteers.Funding Acknowledgements: This study was funded by Arbor Pharmaceuticals, LLC.


2019 ◽  
Vol 69 (1) ◽  
pp. 42-49
Author(s):  
Jessie Usaga ◽  
Jacqueline Aiello

La presencia de gluten en alimentos etiquetados como libres de gluten (LG) representa una preocupación para la salud de pacientes celíacos, y personas intolerantes y sensibles a este conjunto de proteínas. Sin embargo, esto no ha sido estudiado aún en países centroamericanos. Por tanto, se investigó la presencia de gluten en alimentos etiquetados LG, manufacturados en Costa Rica y disponibles en el mercado entre los años 2016 y 2017 para determinar así el cumplimiento de las regulaciones nacionales e internacionales. Se ha estipulado que dichos alimentos deben contener <20 ppm de gluten. Un total de 173 productos fueron analizados por inmunoensayo (tres muestras por producto; cada una de un lote diferente) utilizando el kit ELISA RIDASCREEN®. 60 marcas de productos, de 32 compañías diferentes, fueron evaluadas identificando 15 categorías de alimentos LG: productos horneados, premezclas y harinas, snacks, granos y cereales, salsas, productos cárnicos, productos de origen marino, bebidas, productos lácteos, pastas, chocolates, aceites, tortillas y arepas, jaleas y mermeladas y otros. Una muestra de uno de los productos analizados presentó >20 ppm de gluten. No obstante, al menos una muestra de 49 productos diferentes (28% de los productos analizados) presentó una concentración cuantificable de gluten (>5 ppm) evidenciando una alta variabilidad en los resultados. Esta investigación evidencia el fuerte compromiso de la industria alimentaria costarricense para cumplir la norma que regula la producción de alimentos LG durante el período de estudio, aunque se alerta acerca de la necesidad de implementar mejoras en los sistemas de producción y vigilancia de estos alimentos. The presence of gluten in gluten free (GF) labelled foods represents a serious health concern to celiac patients and persons intolerant or sensitive to this set of proteins. However, this has not yet been studied in Central American countries. Therefore, the presence of gluten in foods labeled LG, manufactured in Costa Rica and available in the market, between 2016 and 2017, was investigated to determine compliance with national and international regulations. It has been stipulated that such foods must contain <20 ppm of gluten. A total of 173 products were analyzed by immunoassay (three samples per product; each from an independent batch), using the ELISA RIDASCREEN® kit. 60 product brands, from 32 different companies, were evaluated and 15 GF food categories were identified: baked products, baking mixes and flours, snacks, grains and cereals, sauces, meat products, seafood, beverages, dairy products, pasta, chocolates, oils, tortillas and arepas, jams and jellies, and others. Only one sample from one of the tested products presented >20 ppm of gluten. However, at least one sample of 49 different products (28% of products tested) presented a quantifiable concentration of gluten (>5 ppm), showing a high variability of results. This research evidences the strong commitment of the Costa Rican food industry to comply with the norm that regulates the production of LG foods during the study period, even though it warns about the need to implement improvements in the production and surveillance systems of these foods.


2014 ◽  
Vol 58 (10) ◽  
pp. 5900-5908 ◽  
Author(s):  
Carrie A. Morris ◽  
Rolf Pokorny ◽  
Luis Lopez-Lazaro ◽  
Robert M. Miller ◽  
Sarah Arbe-Barnes ◽  
...  

ABSTRACTThe objectives of this study were to characterize any drug-drug interaction between the antimalarial Pyramax (pyronaridine-artesunate [PA]) and the CYP2D6 probe substrate metoprolol and to assess the safety of 60-day or 90-day PA redosing, particularly with regard to liver biochemistry parameters. Healthy adult subjects were randomized to arm A (n= 26) or arm B (n= 30), with the arm A subjects administered 100 mg metoprolol tartrate in the first period, 100 mg metoprolol tartrate with the third of three daily doses of PA in the second period, and three daily doses of PA alone in the 90-day redosing period. The arm B subjects received the three-day PA regimen in the first period, with redosing of the regimen after 60 days in the second period. The noncompartmental pharmacokinetic parameters were computed for metoprolol, its metabolite alpha-hydroxymetoprolol, and pyronaridine. The coadministration of metoprolol and PA was associated with an average 47.93% (90% confidence interval [CI], 30.52, 67.66) increase in the maximum concentration of metoprolol and a 25.60% (90% CI, 15.78, 36.25) increase in the metoprolol area under the concentration-time curve from time zero to the last quantifiable concentration obtained (AUC0-t); these increases most likely resulted from pyronaridine-mediated CYP2D6 inhibition. No interaction effect of metoprolol with pyronaridine was apparent. Following dosing with PA, some subjects experienced rises in liver function tests above the upper limit of normal during the first few days following PA administration. All such elevations resolved typically within 10 days, and up to 30 days at most. In subjects who were redosed, the incidences of alanine aminotransferase (ALT) or aspartate transaminase (AST) level elevations were similar on the first and second administrations, with no marked difference between the 60-day and 90-day redosing.


1998 ◽  
Vol 32 (3) ◽  
pp. 304-308 ◽  
Author(s):  
David M Tenero ◽  
David E Martin ◽  
Bernard E Ilson ◽  
Duane A Boyle ◽  
Steven C Boike ◽  
...  

OBJECTIVE: To assess the effect of ranitidine on the pharmacokinetics of eprosartan in healthy male volunteers. DESIGN: Single-center, randomized, open-label, two-period, period-balanced, crossover study. PATIENTS: Seventeen healthy men aged 19 to 43 years. INTERVENTION: In each period (separated by a ≥7 d washout), subjects received a single 400-mg oral dose of eprosartan alone, or a single oral dose of eprosartan 400 mg and ranitidine 150 mg on day 4 after 3 days of ranitidine 150 mg twice daily. Serial pharmacokinetic samples were obtained for up to 24 hours following eprosartan dosing. MAIN OUTCOME MEASURES: Plasma and urine eprosartan concentrations during each treatment session. RESULTS: Eprosartan maximum concentration (Cmax), the AUC from time zero to the last quantifiable concentration (AUC0-t), and renal clearance (Clr) values were approximately 7%, 11%, and 4% lower, respectively, when administered with ranitidine compared with eprosartan alone. The 95% CIs for the ratio of eprosartan plus ranitidine compared with eprosartan alone were 0.81 to 1.07, 0.77 to 1.03, and 0.64 to 1.43, for Cmax, AUC0-t, and Clr, respectively, indicating no statistically significant difference between regimens. CONCLUSIONS: Repeated doses of ranitidine did not have a marked effect on the single-dose pharmacokinetics of eprosartan. OBJETIVO: Evaluar el efecto de ranitidina en la farmacocinética de eprosartan en pacientes voluntarios saludables. DISEÑO: Centro sencillo, estudio randomizado, rotulación abierta, dos períodos, período cruzado balanceado. PACIENTES: Díecisiete hombres saludables entre 19 a 43 años. INTERVENCIÓN: En cada período (separado por 7 d o más sín medicamento), los pacientes recibieron una dosis oral de eprosartan 400 mg solamente, o una dosis oral eprosartan 400 mg y ranitidina 150 mg 2 veces al día. Muestras en serie sobre la farmacocinética fueron obtenidas hasta 24 horas después de la dosis de eprosartan. MEDICIÓN DE RESULTADOS: Concentraciones en plasma y orina de eprosartan durante cada período de tratamiento. RESULTADOS: Los valores promedio de concentración máxima (Cmax), ABC0-t, y depuración renal (Clr) de eprosartan fueron aproximadamente 7%, 11%, y 4% más bajo, respectivamente, comparado con eprosartan sólo. En intervalos de un 95% de confianza, la razón de eprosartan y ranitidina comparado con eprosartan sólo fueron 0.81 a 1.07, 0.77 a 1.03, y 0.64 a 1.43 para Cmax, ABC0-t, y Clr, respectivamente, indicando que no hay diferencia estadística entre ambos régimenes. CONCLUSIONES: Dosis repetidas de ranitidina no producen un efecto marcado en la farmacocinética de eprosartan en dosis sencillas. OBJECTIF: Évaluer l'effet de la ranitidine sur la pharmacocinétique de l'éprosartan chez des volontaires sains. DEVIS EXPÉRIMENTAL: Étude à échantillonagealéatoire, ouverte, en chassécroisé comprenant deux périodes, et réalisée dans un seul établissement. PATIENTS: Dix-sept hommes sains, âgés entre 19 et 43 ans. INTERVENTION: Dans chaque période (séparée par 7 j de sevrage thérapeutique), les volontaires reçurent soit une dose unique de 400 mg d'éprosartan, ou une dose unique de 400 mg d'éprosartan et 150 mg de ranitidine au jour 4, suivant l'administration de 150 mg de ranitidine aux 12 heures les 3 premiers jours. Plusieurs échantillons pharmacocinétiques furent obtenus durant les 24 heures suivant l'administration d'éprosartan. MESURES DE L'ÉFFET: Concentrations urinaires et plasmatiques d'éprosartan durant chacune des deux périodes de traitement. RÉSULTATS: Quand l'éprosartan fut administré avec la ranitidine, la concentration maximale, la surface sous la courbe, et la clairance rénale d'éprosartan étaient en moyenne approximativement 7%, 11%, et 4% inférieures, respectivement, aux valeurs obtenues avec l'éprosartan administré seul. Aucune différence statistiquement significative n'a été observée entre l'éprosartan administré avec la ranitidine et l'éprosartan seul. Les intervalles de confiance à 95% pour les rapports des valeurs entre les deux groupes sont pour la concentration maximale 0.81 à 1.07, la surface sous la courbe 0.77 à 1.03, et la clairance rénale 0.64 à 1.43. CONCLUSIONS: L'administration de doses répétées de ranitidine n'a pas démontré d'effet marqué sur la pharmacocinétique d'une dose unique d'éprosartan.


Author(s):  
Kevan Brown ◽  
John J Gardner ◽  
William J S Lockley ◽  
John R Preston ◽  
David J Wilkinson

A sensitive radioimmunoassay method for sodium cromoglycate in human plasma is described. The lowest quantifiable concentration of sodium cromoglycate is 0·93 nmol/l when 0·1 ml plasma samples are analysed. Direct analysis of sodium cromoglycate concentrations in plasma samples collected up to several hours after the administration of single therapeutic doses of the compound is possible. An antiserum raised in a sheep, radioligand heterogeneously labelled with iodine-125, and a second antibody technique for the separation of bound and free radioligand are employed. The inter-assay coefficient of variation is less than 14% (n=23). The range of the method is limited; both 0·01 and 0·1 ml volumes of plasma must be analysed to encompass the concentration range 0·93–139 nmol/l which may be encountered in plasma samples from patients and human volunteers. The method is specific for sodium cromoglycate as indicated by a low cross-reactivity of the anti-cromoglycate antiserum with a number of drugs.


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