scholarly journals Amino Acid Plasma Profiles from a Prolonged-Release Protein Substitute for Phenylketonuria: A Randomized, Single-Dose, Four-Way Crossover Trial in Healthy Volunteers

Nutrients ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1653 ◽  
Author(s):  
Mika Scheinin ◽  
Anna Barassi ◽  
Jouni Junnila ◽  
Zsófia Lovró ◽  
Giorgio Reiner ◽  
...  

Several disorders of amino acid (AA) metabolism are treated with a protein-restricted diet supplemented with specific AA mixtures. Delivery kinetics impacts AA absorption and plasma concentration profiles. We assessed plasma profiles after ingestion of an AA mixture engineered to prolong AA absorption with Physiomimic TechnologyTM (Test) in a randomized, single-dose, four-way crossover trial in healthy volunteers (Trial Registration: ISRCTN11016729). In a two-step hypothesis, the primary endpoints were (i) significant reduction in peak plasma concentrations (Cmax) of essential amino acids (EAAs) while (ii) maintaining EAA bioavailability (AUC0-300 min) compared to a free AA mixture (Reference). Secondary endpoints included effects on plasma profiles of other AA groups and effects on several metabolic markers. Thirty subjects completed the study. Both co-primary endpoints were met: Cmax for EAAs was 27% lower with the Test product compared to the Reference product (ratio, 0.726, p < 0.0001); overall plasma EAA levels from the two AA mixtures was within the pre-specified bioequivalence range (AUC0-300min ratio, 0.890 (95% CI: 0.865, 0.915)). These findings were supported by the results of secondary endpoints. Prolongation of AA absorption was associated with modulation of several metabolic markers. It will be important to understand whether this can improve the long-term management of disorders of AA metabolism.

Nutrients ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 3189
Author(s):  
Mika Scheinin ◽  
Jouni Junnila ◽  
Giorgio Reiner ◽  
Anita MacDonald ◽  
Ania C. Muntau

Nitrogen balance is the difference between nitrogen excreted as urea and nitrogen ingested, mainly in proteins. Increased circulating concentrations of amino acids (AA) in the bloodstream are usually associated with proportional increases in the production and excretion of urea. Previously, we reported results from a randomized, controlled, single-dose, crossover trial in healthy adult volunteers (n = 30) (Trial Registration: ISRCTN11016729), in which a Test product (prolonged-release AA mixture formulated with Physiomimic Technology™ (PT™)) significantly slowed down the release and reduced the peak plasma concentrations of essential AAs compared with a free AA mixture (Reference product) while maintaining essential AA bioavailability. Here, we report an assessment of the nitrogen balance from the same study. The amount of nitrogen contained in plasma AAs, levels of blood urea nitrogen (BUN) (p < 0.0001) and changes in BUN (p < 0.0001) were smaller after the Test product compared with the Reference product. These findings suggest that the production of urea in proportion to systemic AA availability was significantly smaller after the administration of the Test product compared with the Reference product and that the test product conferred the increased utilization of AAs for protein synthesis and reduced their oxidation and conversion to urea. In the clinical setting, it is possible that the effects of PT™ observed on the disposition of free AAs in this study may translate to health benefits in terms of physiological body composition and growth if used for the treatment of subjects with phenylketonuria (PKU). Further investigation in patients with PKU is warranted.


Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Michael J Koren ◽  
Patrick M Moriarty ◽  
Joel Neutel ◽  
Seth J Baum ◽  
Martha Hernandez-Illas ◽  
...  

Introduction: Mendelian and epidemiological randomization studies have identified lipoprotein(a) [Lp(a)] as a risk factor for myocardial infarction and other atherosclerotic events. There are currently no approved medicines that selectively target Lp(a) and have demonstrated reduction in CV events. AMG 890 is a siRNA designed to reduce the production of Lp(a) by targeting mRNA transcribed from the LPA gene. Methods: This phase 1 study evaluated the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of AMG 890. Adults with plasma concentrations of Lp(a) ≥ 70 to ≤ 199 nmol/L (cohorts 1-5), and ≥ 200 nmol/L (cohorts 6-7), were randomized 3:1 to receive a single subcutaneous dose of investigational product (IP; AMG 890 or placebo). The primary endpoints were treatment-emergent adverse events (TEAEs), safety laboratory analytes, vital signs and ECGs. Secondary endpoints included PK parameters and percent reduction from baseline in Lp(a). Results: 64 subjects were administered IP (cohorts 1-5: AMG 890, n=30, doses: 3 mg, 9 mg, 30 mg, 75 mg, 225 mg; placebo, n=10; cohorts 6-7: AMG 890, n=18, doses: 9 mg and 75 mg; placebo, n=6). The most common TEAEs were headache (10% AMG 890; 25% placebo) and upper respiratory tract infection (15% AMG 890; 13% placebo); no safety concerns were identified for AMG 890. In cohorts 1-5, single doses of AMG 890 effectively reduced mean Lp(a) levels from baseline by 71-96% (based on doses) at Day 43, and by 80-94% at Day 113 (cohorts 2-5). In cohorts 6 and 7, single doses of AMG 890 effectively reduced mean Lp(a) levels from baseline by 75% and 89% at Day 43, respectively, and by 61% and 80% at Day 113, respectively. Conclusions: In adults with elevated Lp(a), single-dose treatment of AMG 890 was well-tolerated and significantly reduced Lp(a) with observed maximal percent reductions of > 90% and effects persisting for more than 6 months at doses of 9 mg or higher.


Author(s):  
Michael S. McEntire ◽  
Jennifer M. Reinhart ◽  
Sherry K. Cox ◽  
Krista A. Keller

Abstract OBJECTIVE To identify the antifungal susceptibility of Nanniziopsis guarroi isolates and to evaluate the single-dose pharmacokinetics of orally administered terbinafine in bearded dragons. ANIMALS 8 healthy adult bearded dragons. PROCEDURES 4 isolates of N guarroi were tested for antifungal susceptibility. A compounded oral solution of terbinafine (25 mg/mL [20 mg/kg]) was given before blood (0.2 mL) was drawn from the ventral tail vein at 0, 4, 8, 12, 24, 48, 72, and 96 hours after administration. Plasma terbinafine concentrations were measured with high-performance liquid chromatography. RESULTS The antifungal minimum inhibitory concentrations against N guarroi isolates ranged from 4,000 to > 64,000 ng/mL for fluconazole, 125 to 2,000 ng/mL for itraconazole, 125 to 2,000 ng/mL for ketoconazole, 125 to 1,000 ng/mL for posaconazole, 60 to 250 ng/mL for voriconazole, and 15 to 30 ng/mL for terbinafine. The mean ± SD peak plasma terbinafine concentration in bearded dragons was 435 ± 338 ng/mL at 13 ± 4.66 hours after administration. Plasma concentrations remained > 30 ng/mL for > 24 hours in all bearded dragons and for > 48 hours in 6 of 8 bearded dragons. Mean ± SD terminal half-life following oral administration was 21.2 ± 12.40 hours. CLINICAL RELEVANCE Antifungal susceptibility data are available for use in clinical decision making. Results indicated that administration of terbinafine (20 mg/kg, PO, q 24 to 48 h) in bearded dragons may be appropriate for the treatment of dermatomycoses caused by N guarroi. Clinical studies are needed to determine the efficacy of such treatment.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Furong Qiu ◽  
Jian Jiang ◽  
Yueming Ma ◽  
Guangji Wang ◽  
Chenglu Gao ◽  
...  

The aim of this study was to investigate the effect of single- and multidose administration of the ethanol extract of danshen on in vivo CYP3A activity in healthy volunteers. A sequential, open-label, and three-period pharmacokinetic interaction study design was used based on 12 healthy male individuals. The plasma concentrations of midazolam and its metabolite 1-hydroxymidazolam were measured. Treatment with single dose of the extract caused the meanCmaxof midazolam to increase by 87% compared with control. After 10 days of the danshen extract intake, the mean AUC0–12,Cmax, andt1/2of midazolam were decreased by 79.9%, 66.6%, and 43.8%, respectively. The mean clearance of midazolam was increased by 501.6% compared with control. The in vitro study showed that dihydrotanshinone I in the extract could inhibit CYP3A, while tanshinone IIA and cryptotanshinone could induce CYP3A. In conclusion, a single-dose administration of the danshen extract can inhibit intestinal CYP3A, but multidose administration can induce intestinal and hepatic CYP3A.


1982 ◽  
Vol 63 (s8) ◽  
pp. 451s-453s ◽  
Author(s):  
W. Kirch ◽  
H. Spahn ◽  
H. Köhler ◽  
E. Mutschler

1. Pharmacokinetics of metoprolol, propranolol and atenolol were investigated in six healthy volunteers after 7 days of oral monotherapy with these drugs and after 7 days concurrent administration, with each of these β-adrenoceptor antagonists with cimetidine. 2. Cimetidine did not interact with atenolol, whereas mean peak plasma concentrations of metoprolol were increased by 70%, and those of propranolol by 95% with concurrent administration of cimetidine (P < 0.05). 3. The area under the plasma concentration-time curve for propranolol and metoprolol was similarly increased (P < 0.05).


2019 ◽  
Vol 65 (01) ◽  
pp. 11-17
Author(s):  
Dimce Zafirov ◽  
Jasmina Trojacanec ◽  
Dragica Zendelovska ◽  
Nikola Kolovcevski ◽  
Bojan Labachevski

Zolpidem is a hypnotic agent with a chemical structure unrelated to benzodiazepines, barbiturates, pyrrolopyrazines, pyrazolopyrimidines or other drugs with known hypnotic properties. Zolpidem as conventional tablets is used as a hypnotic agent in the short-term management of insomnia, generally for periods not exceeding 7–10 days in duration. The objective of this study was to evaluate and compare the relative bioavailability, and therefore the bioequivalence of Zolpidem 10 mg test formulation versus a reference Zolpidem 10 mg formulation, following a single dose administration under fasting conditions The study was a single center, open, single dose, randomized, two - way crossover study in healthy male volunteers with a wash - out period of one week between study periods. Twenty-eight male healthy volunteers, aged 20-49 years were included into study. Blood samples for determination of zolpidem plasma concentrations were withdraw at 0 (pre-drug administration), 0.33, 0.66, 1, 1.33, 1.66, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 10, 12, 16 and 24 hours post-drug. The zolpidem concentrations in plasma were determined with HPLC, using fluorescence detection. The test formulation of zolpidem, dosed at 10 mg is bioequivalent for primary zolpidem parameters (Cmax, AUC0-t and AUC0-∞) to the reference formulation after a single oral administration of 10 mg zolpidem. Both medications are well tolerated with no serious adverse events. Thus, in view of the clinical use, both formulations are exchangeable without restrictions. Keywords: Zolpidem, bioavailability, bioequivalence study, single-dose


2020 ◽  
Vol 86 (4) ◽  
pp. 567-575 ◽  
Author(s):  
Donghoon Shin ◽  
Yoon Jung Lee ◽  
Jihye Choi ◽  
Dahyoung Lee ◽  
Minjeong Park ◽  
...  

Abstract Purpose To compare pharmacokinetics, safety, tolerability, and immunogenicity between SB8, a bevacizumab biosimilar, and the European Union (EU) and United States (US) reference products (bevacizumab-EU, bevacizumab-US). Methods In this randomized, double-blind, parallel-group, and single-dose study, healthy volunteers were randomized to receive a 3 mg/kg dose of SB8, bevacizumab-EU, or bevacizumab-US via intravenous infusion. Primary endpoints were area under the concentration–time curve from time zero to infinity (AUCinf) and to the last quantifiable concentration (AUClast), and maximum observed serum concentration (Cmax). Bioequivalence was achieved if 90% confidence intervals (CIs) for the ratios of the geometric least squares means (LSMeans) of primary endpoints were within the predefined bioequivalence margins of 80.00–125.00%. Safety and immunogenicity were also investigated. Results The 90% CIs for the geometric LSMean ratios of AUCinf, AUClast and Cmax were all within the prespecified bioequivalence margins. Geometric LSMean ratios for SB8/bevacizumab-EU, SB8/bevacizumab-US and bevacizumab-EU/bevacizumab-US were 88.01%, 88.48% and 100.54% for AUCinf, 88.65%, 89.08% and 100.49% for AUClast and 99.59%, 101.15% and 101.56% for Cmax, respectively. Incidence of treatment-emergent adverse events (TEAEs) across treatment groups was comparable (SB8: 50.0%, bevacizumab-EU: 37.5%, bevacizumab-US: 53.8%). Most TEAEs were mild and considered as not related to the study drug. No deaths or treatment discontinuations due to adverse events occurred. Incidence of anti-drug antibodies was also comparable between all groups and no neutralizing antibodies were detected. Conclusion This study demonstrated pharmacokinetic bioequivalence and similar safety and immunogenicity profiles of SB8 to both reference products, bevacizumab-EU and bevacizumab-US, and of bevacizumab-EU to bevacizumab-US. Clinicaltrials.gov identifier NCT02453672 (submitted date); EudraCT number: 2015-001,026-41.


1974 ◽  
Vol 12 (12) ◽  
pp. 47-48

Nitrofurantoin is effective in the treatment of acute urinary tract infections, but its usefulness is limited by the high incidence of unwanted effects. When used in the recommended dose of 100 mg four times daily about a quarter of the patients may suffer nausea and vomiting.1 A single dose of 100 mg at night for the prophylaxis of urinary infections2 caused symptoms in 41% of patients.3 These unwanted effects seem to be related to peak plasma concentrations of the drug rather than to its action on the gut.


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