scholarly journals Evaluation of a Potential Metabolism-Mediated Drug-Drug Interaction Between Atomoxetine and Bupropion in Healthy Volunteers

2016 ◽  
Vol 19 (2) ◽  
pp. 198 ◽  
Author(s):  
Ioana Todor ◽  
Adina Popa ◽  
Maria Neag ◽  
Dana Muntean ◽  
Corina Bocsan ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Plasma Concentrations ◽  
Systemic Exposure ◽  
Pharmacokinetic Profile ◽  
Pharmacokinetic Parameters ◽  
Open Label ◽  
Cyp2d6 Activity ◽  
The Mean ◽  
The Impact ◽  
Pharmacokinetic Drug

Purpose: To evaluate the impact of bupropion on the pharmacokinetic profile of atomoxetine and its main active metabolite (glucuronidated form), 4-hydroxyatomoxetine-O-glucuronide, in healthy volunteers. Methods: An open-label, non-randomized, two-period, sequential clinical trial was conducted as follows: during Period I (Reference), each volunteer received a single oral dose of 25 mg atomoxetine, whilst during Period II (Test), a combination of 25 mg atomoxetine and 300 mg bupropion was administered to all volunteers, after a pretreatment regimen with bupropion for 7 days. Next, after determining atomoxetine and 4-hydroxyatomoxetine-O-glucuronide plasma concentrations, their pharmacokinetic parameters were calculated using a noncompartmental method and subsequently compared to determine any statistically significant differences between the two periods. Results: Bupropion intake influenced all the pharmacokinetic parameters of both atomoxetine and its metabolite. For atomoxetine, Cmax increased from 226±96.1 to 386±137 ng/mL and more importantly, AUC0-∞ was significantly increasedfrom 1580±1040 to 8060±4160 ng*h/mL, while the mean t1/2 was prolonged after bupropion pretreatment. For 4-hydroxyatomoxetine-O-glucuronide, Cmax and AUC0-∞  were decreased from 707±269 to 212±145 ng/mL and from 5750±1240 to 3860±1220 ng*h/mL, respectively. Conclusions: These results demonstrated that the effect of bupropion on CYP2D6 activity was responsible for an increased systemic exposure to atomoxetine (5.1-fold) and also for a decreased exposure to its main metabolite (1.5-fold). Additional studies are required in order to evaluate the clinical relevance of this pharmacokinetic drug interaction.This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.

scholarly journals Opposite Effects of Single-Dose and Multidose Administration of the Ethanol Extract of Danshen on CYP3A in Healthy Volunteers

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Furong Qiu ◽  
Jian Jiang ◽  
Yueming Ma ◽  
Guangji Wang ◽  
Chenglu Gao ◽  
...  
Keyword(s):  
Single Dose ◽  
Healthy Volunteers ◽  
Plasma Concentrations ◽  
In Vitro Study ◽  
Ethanol Extract ◽  
Tanshinone Iia ◽  
Open Label ◽  
The Mean

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.

scholarly journals Open-Label, Dose Escalation Study of the Safety and Pharmacokinetic Profile of Tefibazumab in Healthy Volunteers

2005 ◽  
Vol 49 (3) ◽  
pp. 959-962 ◽  
Author(s):  
Sandra Reilley ◽  
Eric Wenzel ◽  
Laurie Reynolds ◽  
Beth Bennett ◽  
Joseph M. Patti ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Dose Escalation ◽  
Maximum Concentration ◽  
Dose Range ◽  
Plasma Concentrations ◽  
Open Label ◽  
Serious Adverse Events ◽  
Dose Escalation Study ◽  
Label Dose ◽  
The Mean

ABSTRACT Tefibazumab (Aurexis) is a humanized monoclonal antibody being evaluated as adjunctive therapy for the treatment of Staphylococcus aureus infections. This open-label, dose escalation study evaluated the safety and pharmacokinetics of tefibazumab in 19 healthy volunteers aged 18 to 69 years. Each subject received a single administration of tefibazumab at a dose of 2, 5, 10, or 20 mg/kg of body weight infused over 15 min. Plasma samples for pharmacokinetic assessments were obtained before infusion as well as 1, 6, 12, and 24 h and 3, 4, 7, 21, 28, 42, and 56 days after dosing. Plasma concentrations of tefibazumab were detected 1 h after the end of the infusion, with a mean maximum concentration of drug in serum (C max) of 59, 127, 252, and 492 μg/ml following doses of 2, 5, 10, and 20 mg/kg, respectively. The median time to maximum concentration of drug in serum (T max) was 1.0 h for each dose. The mean elimination half-life (t 1/2) was approximately 22 days. The volume of distribution (V) was 4.7, 6.7, 7.2, and 7.2 liters after doses of 2, 5, 10, and 20 mg/kg, respectively. Clearance (CL) was 6.0, 9.2, 10.2, and 9.9 ml/hr, respectively. At the highest dose, plasma levels of tefibazumab were >100 μg/ml for 21 days. On day 56, the mean plasma concentrations were 6.3, 10.0, 16.4, and 30.5 μg/ml for the 2, 5, 10, and 20 mg/kg doses, respectively. Tefibazumab exhibited linear kinetics across doses of 5, 10, and 20 mg/kg. No anti-tefibazumab antibodies were detected after dosing in any subject. There were no serious adverse events, and tefibazumab was well tolerated over the entire dose range.

scholarly journals Bioequivalence of levamlodipine besylate tablets in healthy Chinese subjects: A single-dose and two-period crossover randomized study

2020 ◽  
Author(s):  
Li Xin ◽  
Chenjing Wang ◽  
Ting Li ◽  
Yanping Liu ◽  
Shuqin Liu ◽  
...  
Keyword(s):  
Single Dose ◽  
Randomized Study ◽  
Plasma Concentrations ◽  
Bioequivalence Study ◽  
Pharmacokinetic Parameters ◽  
Open Label ◽  
Liquid Chromatography Tandem Mass ◽  
The Mean ◽  
Healthy Chinese ◽  
Chinese Subjects

Abstract Background: Levamlodipine, a calcium channel blocker, has been show act as a cardiovascular drug. To compare the pharmacokinetic parameters between levamlodipine (test formulation) at a single dose of 5 mg and amlodipine (reference formulation) at a single dose of 10 mg, the bioequivalence study was carried out.Methods: A single-dose randomized, open-label, two-period crossover study was designed in healthy Chinese subjects. 48 subjects were divided into fasted and fed groups equally. The subjects randomly received the test or reference formulations at the rate of 1:1. Following a 21-day washout period, the alternative formulations were received. The blood samples were collected at 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 24, 36, 48, 72, 96, 120, 144, 168 hours later. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was applied to determine the plasma concentrations of levamlodipine. Adverse events were recorded.Results: The 90% confidence intervals (CIs) of the ratio of geometric means (GMRs) of Cmax, AUC0-t, and AUC0-∞ under both fasted and fed conditions were within the prespecified bioequivalence limits between 80~125%. Under fasted conditions, 24 subjects were enrolled and completed the study. The mean Cmax was (2.70±0.49) ng/mL, AUC0-t was (141.32±36.24) ng×h/mL and AUC0-∞ was (157.14±45.65) ng×h/mL after a single dose of 5 mg levamlodipine. The mean Cmax was (2.83±0.52) ng/mL, AUC0-t was (153.62±33.96) ng×h/mL and AUC0-∞ was (173.05±41.78) ng×h/mL after a single dose of 10 mg amlodipine. Under fed conditions, 24 subjects were enrolled and completed the study. The mean Cmax was (2.73±0.55) ng/mL, AUC0-t was (166.93±49.96) ng×h/mL and AUC0-∞ was (190.99±70.89) ng×h/mL after a single dose of 5 mg levamlodipine. The mean Cmax was (2.87±0.81) ng/mL AUC0-t was (165.46±43.58) ng×h/mL and AUC0-∞ was (189.51±64.70) ng×h/mL after a single dose of 10 mg amlodipine. Serious adverse event was not observed.Conclusion: The trial confirmed that levamlodipine at a single dose of 5 mg and amlodipine at a single dose of 10 mg were bioequivalent under both fasted condition and fed condition.Trial registration: Cinicaltrials, NCT04411875. Registered 3 June 2020 - Retrospectively registered, https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S0009W1Q&selectaction=Edit&uid=U00050YQ&ts=3&cx=-6iqkm8

Clinical pharmacodynamics of continuous infusion teniposide: systemic exposure as a determinant of response in a phase I trial.

1987 ◽  
Vol 5 (7) ◽  
pp. 1007-1014 ◽  
Author(s):  
J H Rodman ◽  
M Abromowitch ◽  
J A Sinkule ◽  
F A Hayes ◽  
G K Rivera ◽  
...  
Keyword(s):  
Continuous Infusion ◽  
Plasma Concentrations ◽  
Systemic Exposure ◽  
Pharmacokinetic Parameters ◽  
Pharmacokinetic Variability ◽  
Significant Relationships ◽  
Clinical Responses ◽  
The Mean ◽  
Dose Levels ◽  
Severe Mucositis

Teniposide (VM-26) is an effective anticancer drug usually administered as a short infusion in doses of 150 to 165 mg/m2. The objectives of the trial reported here were to evaluate clinical responses and assess pharmacokinetic parameters as a determinant of outcome when VM-26 was administered as a 72-hour continuous infusion (CI) with doses escalated from 300 to 750 mg/m2 per course. Twenty-eight patients with recurrent leukemia, lymphoma, or neuroblastoma received 53 courses of CI VM-26 and 16 had measurable responses. There were two partial remissions and one stable disease among seven neuroblastoma patients and 13 of 21 leukemia/lymphoma patients had oncolytic responses (greater than or equal to 75% decrease in circulating blasts). Toxicity included moderate to severe mucositis and myelosuppression. Pharmacokinetic parameters determined during 35 courses administered to 23 patients were highly variable. Clearance (CI) ranged between 3.7 and 43.8 ml/min/m2, resulting in VM-26 plasma concentrations from 2.8 to 30.6 mg/L across all dose levels. The interpatient pharmacokinetic variability reflected in CI and VM-26 steady state concentrations (Css), obscured any dose-response relationship. However, when pharmacokinetic parameters for responding and nonresponding patients were compared, statistically significant relationships were observed. For responders, the mean Css was 15.2 mg/L and mean CI was 12.1 mL/min/m2; for nonresponders, mean Css was 6.2 mg/L (P less than .01) and mean CI was 21.3 mL/min/m2 (P less than .05). Thus, patients with higher CI and lower Css were less likely to respond. Clinical responses occurred in ten of ten patients with Css greater than 12 mg/L, and only five of 13 patients with Css less than 12 mg/L (P less than .01). In this study, interpatient pharmacokinetic variability yielded a four- to sixfold difference in intensity of systemic exposure (Css) within the same dose level, which was an important determinant of clinical response. These data indicate that achieving a VM-26 target concentration for individual patients could ensure an increased intensity of systemic exposure in patients with a high CI and improve the likelihood of effective therapy.

scholarly journals The Bioavailability and Pharmacokinetics of Silymarin SMEDDS Formulation Study in Healthy Thai Volunteers

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Chuleegone Sornsuvit ◽  
Darunee Hongwiset ◽  
Songwut Yotsawimonwat ◽  
Manatchaya Toonkum ◽  
Satawat Thongsawat ◽  
...  
Keyword(s):  
Single Dose ◽  
Healthy Volunteers ◽  
Pharmacokinetic Study ◽  
Oral Bioavailability ◽  
Pharmacokinetic Parameters ◽  
Open Label ◽  
Blood Samples ◽  
Rapid Absorption ◽  
The Mean

The present study aimed to determine the pharmacokinetic parameters and bioavailability of silymarin 140 mg SMEDDS formulation. An open-label, single-dose pharmacokinetic study was conducted. Twelve healthy volunteers were included in the study. After the volunteers had fasted overnight for 10 h, a single-dose generic silymarin 140 mg SMEDDS soft capsule was administered. Then 10 ml blood samples were taken at 0.0, 0.25, 0.50, 0.75, 1.0, 1.33, 1.67, 2.0, 2.5, 3.0, 4.0, 6.0, 8.0, 10.0, and 12.0 h. The plasma silybin concentrations were analyzed using validated LC-MS/MS. The pharmacokinetic parameters were analyzed and calculated. The pharmacokinetic parameters were calculated after silymarin had been administered as a single capsule. The mean (range) Cmax was 812.43 (259.47–1505.47) ng/ml at 0.80 (0.25–1.67) h (tmax). The mean (range) AUC0-t and AUC0-inf were 658.80 (268.29–1045.01) ng.h/ml and 676.98 (274.10–1050.96) ng.h/ml, respectively. The mean ke and t1/2 were 0.5386 h-1 and 1.91 h, respectively. The silymarin SMEDDS formulation soft capsule showed rapid absorption and high oral bioavailability.

scholarly journals Pharmacokinetic Characterisation and Comparison of Bioavailability of Intranasal Fentanyl, Transmucosal, and Intravenous Administration through a Three-Way Crossover Study in 24 Healthy Volunteers

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
S. Nardi-Hiebl ◽  
J. W. Ndieyira ◽  
Y. Al Enzi ◽  
W. Al Akkad ◽  
T. Koch ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Intravenous Administration ◽  
Intranasal Administration ◽  
Geometric Mean ◽  
Plasma Concentrations ◽  
Pharmacokinetic Parameters ◽  
Published Data ◽  
Open Label ◽  
Single Dose Study ◽  
Transmucosal Administration

Background. For more than 60 years, the synthetic opioid fentanyl has been widely used in anaesthesia and analgesia. While the intravenous formulation is primarily used for general anaesthesia and intensive care settings, the drug’s high lipophilic properties also allow various noninvasive routes of administration. Published data suggest that intranasal administration is also attractive for use as intranasal patient-controlled analgesia (PCA). A newly developed intranasal fentanyl formulation containing 47 μg fentanyl, intravenous fentanyl, and oral transmucosal fentanyl citrate were characterised, and bioavailability was compared to assess the suitability of the intranasal formulation for an intranasal PCA product. Methods. 27 healthy volunteers were enrolled in a single-centre, open-label, randomised (order of treatments), single-dose study in a three-period crossover design. The pharmacokinetics of one intranasal puff of fentanyl formulation (47 μg, 140 mL per puff), one short intravenous infusion of 50 μg fentanyl, and one lozenge with an integrated applicator (200 μg fentanyl) were studied, and bioavailability was calculated. Blood samples were collected over 12 hours, and plasma concentrations of fentanyl were determined by HPLC with MS/MS detection. Results. 24 volunteers completed the study. The geometric mean of AUC0-tlast was the highest with oral transmucosal administration (1106 h  ∗  pg/ml, CV% = 32.86), followed by intravenous (672 h  ∗  pg/ml, CV% = 32.18) and intranasal administration (515 h  ∗  pg/ml, CV% = 30.10). Cmax was 886 pg/ml (CV% = 59.38) for intravenous, 338 pg/ml (CV% = 45.61) for intranasal, and 310 pg/ml (CV% = 29.58) for oral transmucosal administration. tmax was shortest for intravenous administration (0.06 h, SD = 0.056), followed by intranasal (0.21 h, SD = 0.078) and oral transmucosal administration (1.20 h, SD = 0.763). Dose-adjusted relative bioavailability was determined to be 74.70% for the intranasal formulation and 41.25% for the oral transmucosal product. In total, 38 adverse events (AEs) occurred. Fourteen AEs were potentially related to the investigational items. No serious AE occurred. Conclusion. Pharmacokinetic parameters and bioavailability of the investigated intranasal fentanyl indicated suitability for its intended use as an intranasal PCA option.

scholarly journals Bioequivalence of levamlodipine besylate tablets in healthy Chinese subjects: A single-dose and two-period crossover randomized study

2020 ◽  
Author(s):  
Li Xin ◽  
Chenjing Wang ◽  
Ting Li ◽  
Yanping Liu ◽  
Shuqin Liu ◽  
...  
Keyword(s):  
Single Dose ◽  
Randomized Study ◽  
Plasma Concentrations ◽  
Bioequivalence Study ◽  
Pharmacokinetic Parameters ◽  
Open Label ◽  
Liquid Chromatography Tandem Mass ◽  
The Mean ◽  
Healthy Chinese ◽  
Chinese Subjects

Abstract Background: Levamlodipine, a calcium channel blocker, has been show act as a cardiovascular drug. To compare the pharmacokinetic parameters between levamlodipine (test formulation) at a single dose of 5 mg and amlodipine (reference formulation) at a single dose of 10 mg, the bioequivalence study was carried out.Methods: A single-dose randomized, open-label, two-period crossover study was designed in healthy Chinese subjects. 48 subjects were divided into fasted and fed groups equally. The subjects randomly received the test or reference formulations at the rate of 1:1. Following a 21-day washout period, the alternative formulations were received. The blood samples were collected at 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 24, 36, 48, 72, 96, 120, 144, 168 hours later. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was applied to determine the plasma concentrations of levamlodipine. Adverse events were recorded.Results: The 90% confidence intervals (CIs) of the ratio of geometric means (GMRs) of Cmax, AUC0-t, and AUC0-∞ under both fasted and fed conditions were within the prespecified bioequivalence limits between 80~125%. Under fasted conditions, 24 subjects were enrolled and completed the study. The mean Cmax was (2.70±0.49) ng/mL, AUC0-t was (141.32±36.24) ng×h/mL and AUC0-∞ was (157.14±45.65) ng×h/mL after a single dose of 5 mg levamlodipine. The mean Cmax was (2.83±0.52) ng/mL, AUC0-t was (153.62±33.96) ng×h/mL and AUC0-∞ was (173.05±41.78) ng×h/mL after a single dose of 10 mg amlodipine. Under fed conditions, 24 subjects were enrolled and completed the study. The mean Cmax was (2.73±0.55) ng/mL, AUC0-t was (166.93±49.96) ng×h/mL and AUC0-∞ was (190.99±70.89) ng×h/mL after a single dose of 5 mg levamlodipine. The mean Cmax was (2.87±0.81) ng/mL AUC0-t was (165.46±43.58) ng×h/mL and AUC0-∞ was (189.51±64.70) ng×h/mL after a single dose of 10 mg amlodipine. Serious adverse event was not observed.Conclusion: The trial confirmed that levamlodipine at a single dose of 5 mg and amlodipine at a single dose of 10 mg were bioequivalent under both fasted condition and fed condition.Trial registration: Cinicaltrials, NCT04411875. Registered 3 June 2020 - Retrospectively registered, https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S0009W1Q&selectaction=Edit&uid=U00050YQ&ts=3&cx=-6iqkm8

scholarly journals Bioequivalence of levamlodipine besylate tablets in healthy Chinese subjects: a single-dose and two-period crossover randomized study

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Xin Li ◽  
Chenjing Wang ◽  
Ting Li ◽  
Yanping Liu ◽  
Shuqin Liu ◽  
...  
Keyword(s):  
Single Dose ◽  
Randomized Study ◽  
Plasma Concentrations ◽  
Bioequivalence Study ◽  
Pharmacokinetic Parameters ◽  
Open Label ◽  
Liquid Chromatography Tandem Mass ◽  
The Mean ◽  
Healthy Chinese ◽  
Chinese Subjects

Abstract Background Levamlodipine, a calcium channel blocker, has been show act as a cardiovascular drug. To compare the pharmacokinetic parameters between levamlodipine (test formulation) at a single dose of 5 mg and amlodipine (reference formulation) at a single dose of 10 mg, the bioequivalence study was carried out. Methods A single-dose randomized, open-label, two-period crossover study was designed in healthy Chinese subjects. 48 subjects were divided into fasted and fed groups equally. The subjects randomly received the test or reference formulations at the rate of 1:1. Following a 21-day washout period, the alternative formulations were received. The blood samples were collected at 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 24, 36, 48, 72, 96, 120, 144, 168 h later. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was applied to determine the plasma concentrations of levamlodipine. Adverse events were recorded. Results The 90% confidence intervals (CIs) of the ratio of geometric means (GMRs) of Cmax, AUC0-t, and AUC0-∞ under both fasted and fed conditions were within the prespecified bioequivalence limits between 80 ~ 125%. Under fasted conditions, 24 subjects were enrolled and completed the study. The mean Cmax was (2.70 ± 0.49) ng/mL, AUC0-t was (141.32 ± 36.24) ng × h/mL and AUC0-∞ was (157.14 ± 45.65) ng × h/mL after a single dose of 5 mg levamlodipine. The mean Cmax was (2.83 ± 0.52) ng/mL, AUC0-t was (153.62 ± 33.96) ng × h/mL and AUC0-∞ was (173.05 ± 41.78) ng × h/mL after a single dose of 10 mg amlodipine. Under fed conditions, 24 subjects were enrolled and completed the study. The mean Cmax was (2.73 ± 0.55) ng/mL, AUC0-t was (166.93 ± 49.96) ng × h/mL and AUC0-∞ was (190.99 ± 70.89) ng × h/mL after a single dose of 5 mg levamlodipine. The mean Cmax was (2.87 ± 0.81) ng/mL AUC0-t was (165.46 ± 43.58) ng × h/mL and AUC0-∞ was (189.51 ± 64.70) ng × h/mL after a single dose of 10 mg amlodipine. Serious adverse event was not observed. Conclusion The trial confirmed that levamlodipine at a single dose of 5 mg and amlodipine at a single dose of 10 mg were bioequivalent under both fasted condition and fed condition. Trial registration Cinicaltrials, NCT04411875. Registered 3 June 2020 - Retrospectively registered

scholarly journals Effects of Danshen Ethanol Extract on the Pharmacokinetics of Fexofenadine in Healthy Volunteers

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Furong Qiu ◽  
Jin Zeng ◽  
Songcan Liu ◽  
Min He ◽  
Leilei Zhu ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Interaction Design ◽  
Plasma Concentrations ◽  
Ethanol Extract ◽  
Pharmacokinetic Interaction ◽  
Tanshinone Iia ◽  
Oral Clearance ◽  
Open Label ◽  
The Mean

This study investigated the effect of multidose administration of danshen ethanol extract on fexofenadine pharmacokinetics in healthy volunteers. A sequential, open-label, two-period pharmacokinetic interaction design was used. 12 healthy male volunteers received a single oral dose of fexofenadine (60 mg) followed by danshen ethanol extract (1 g orally, three times a day) for 10 days, after which they received 1 g of the danshen extract with fexofenadine (60 mg) on the last day. The plasma concentrations of fexofenadine was measured by LC-MS/MS. After 10 days of the danshen extract administration, the mean AUC andCmax⁡of the fexofenadine was decreased by 37.2% and 27.4% compared with the control, respectively. The mean clearance of fexofenadine was increased by 104.9%. Thein vitrostudy showed that tanshinone IIA and cryptotanshinone could induce MDR1 mRNA. This study showed that multidose administration of danshen ethanol extract could increase oral clearance of fexofenadine. The increased oral clearance of fexofenadine is attributable to induction of intestinal P-glycoprotein.

Effect of Colesevelam on Lovastatin Pharmacokinetics

2002 ◽  
Vol 36 (3) ◽  
pp. 392-397 ◽  
Author(s):  
Joanne M Donovan ◽  
James C Kisicki ◽  
Mark R Stiles ◽  
William G Tracewell ◽  
Steven K Burke
Keyword(s):  
Healthy Volunteers ◽  
Mass Spectroscopy ◽  
Plasma Concentrations ◽  
Pharmacokinetic Parameters ◽  
Dosing Regimen ◽  
Open Label ◽  
Before And After ◽  
Split Dosing ◽  
Potential Interactions ◽  
Time Point

OBJECTIVE: To assess potential interactions of colesevelam hydrochloride and lovastatin in healthy volunteers when lovastatin alone was administered with dinner, both lovastatin and colesevelam were administered with dinner, and colesevelam was administered with dinner and lovastatin was administered 4 hours later with a snack. METHODS: A single-center, open-label, 3-period, crossover drug interaction study was performed with 22 healthy volunteers. Blood samples were collected at specified intervals before and after dosing, and plasma concentrations of lovastatin and lovastatin hydroxyacid were measured using a liquid chromatography/mass spectroscopy/mass spectroscopy method. RESULTS: Maximal concentration (Cmax), AUC from time 0 to the last time point measured (AUC0-t), and AUC0-∞ values for lovastatin were 102%, 94%, and 104%, and for lovastatin hydroxyacid were 102%, 91%, and 92%, respectively, of control values when colesevelam and lovastatin were coadministered with dinner. Administration of colesevelam with dinner and lovastatin 4 hours later with a snack resulted in a decreased Cmax and AUC0-t for lovastatin (63% and 37%, respectively; p < 0.05) and an increased Cmax and AUC0-t for lovastatin hydroxyacid (61% and 50%, respectively; p < 0.05), both compared with lovastatin alone administered with dinner. CONCLUSIONS: Colesevelam had no significant effect on lovastatin pharmacokinetics when coadministered with lovastatin at dinner. A split-dosing regimen resulted in alterations in pharmacokinetic parameters for lovastatin and lovastatin hydroxyacid that are likely due to known differences in the pharmacokinetics of lovastatin when administered to patients with meals or in a fasting state.

Sign in / Sign up

Export Citation Format

Share Document