scholarly journals Fosamprenavir with Ritonavir Pharmacokinetics during Pregnancy

2020 ◽  
Vol 64 (4) ◽  
Author(s):  
Ahizechukwu C. Eke ◽  
Jiajia Wang ◽  
Khadija Amin ◽  
David E. Shapiro ◽  
Alice Stek ◽  
...  

ABSTRACT The purpose of this study was to evaluate the pharmacokinetics of ritonavir-boosted fosamprenavir during pregnancy and postpartum. Amprenavir (the active moiety of fosamprenavir) and ritonavir intensive pharmacokinetic evaluations were performed at steady state during the second and third trimesters of pregnancy and postpartum. Plasma concentrations of amprenavir and ritonavir were measured using high-performance liquid chromatography. The target amprenavir area under the concentration-versus-time curve (AUC) was higher than the 10th percentile (27.7 μg · h/ml) of the median area under the curve for ritonavir-boosted fosamprenavir in adults receiving twice-daily fosamprenavir-ritonavir at 700 mg/100 mg. Twenty-nine women were included in the analysis. The amprenavir AUC from time zero to 12 h (AUC0–12) was lower (geometric mean ratio [GMR], 0.60 [confidence interval {CI}, 0.49 to 0.72] [P < 0.001]) while its apparent oral clearance was higher (GMR, 1.68 [CI, 1.38 to 2.03] [P < 0.001]) in the third trimester than postpartum. Similarly, the ritonavir AUC0–12 was lower in the second (GMR, 0.51 [CI, 0.28 to 0.91] [P = 0.09]) and third (GMR, 0.72 [CI, 0.55 to 0.95] [P = 0.005]) trimesters than postpartum, while its apparent oral clearance was higher in the second (GMR, 1.98 [CI, 1.10 to 3.56] [P = 0.06]) and third (GMR, 1.38 [CI, 1.05 to 1.82] [P = 0.009]) trimesters than postpartum. The amprenavir area under the curve exceeded the target for 6/8 (75%) women in the 2nd trimester, 18/28 (64%) in the 3rd trimester, and 19/22 (86.4%) postpartum, and the trough concentrations (Cmin) of amprenavir were 4- to 16-fold above the mean amprenavir-protein-adjusted 50% inhibitory concentration (IC50) of 0.146 μg/ml. Although amprenavir plasma concentrations in women receiving ritonavir-boosted fosamprenavir were lower during pregnancy than postpartum, the reduced amprenavir concentrations were still above the exposures needed for viral suppression.

2012 ◽  
Vol 116 (2) ◽  
pp. 432-447 ◽  
Author(s):  
Evan D. Kharasch ◽  
Pamela Sheffels Bedynek ◽  
Christine Hoffer ◽  
Alysa Walker ◽  
Dale Whittington

Background Methadone disposition and pharmacodynamics are highly susceptible to interactions with antiretroviral drugs. Methadone clearance and drug interactions have been attributed to cytochrome P4503A4 (CYP3A4), but actual mechanisms are unknown. Drug interactions can be clinically and mechanistically informative. This investigation assessed effects of the protease inhibitor indinavir on methadone pharmacokinetics and pharmacodynamics, hepatic and intestinal CYP3A4/5 activity (using alfentanil), and intestinal transporter activity (using fexofenadine). Methods Twelve healthy volunteers underwent a sequential crossover. On three consecutive days they received oral alfentanil plus fexofenadine, intravenous alfentanil, and intravenous plus oral (deuterium-labeled) methadone. This was repeated after 2 weeks of indinavir. Plasma and urine analytes were measured by mass spectrometry. Opioid effects were measured by miosis. Results Indinavir significantly inhibited hepatic and first-pass CYP3A activity. Intravenous alfentanil systemic clearance and hepatic extraction were reduced to 40-50% of control, apparent oral clearance to 30% of control, and intestinal extraction decreased by half, indicating 50% and 70% inhibition of hepatic and first-pass CYP3A activity. Indinavir increased fexofenadine area under the plasma concentration-time curve 3-fold, suggesting significant P-glycoprotein inhibition. Indinavir had no significant effects on methadone plasma concentrations, methadone N-demethylation, systemic or apparent oral clearance, renal clearance, hepatic extraction or clearance, or bioavailability. Methadone plasma concentration-effect relationships were unaffected by indinavir. Conclusions Despite significant inhibition of hepatic and intestinal CYP3A activity, indinavir had no effect on methadone N-demethylation and clearance, suggesting little or no role for CYP3A in clinical disposition of single-dose methadone. Inhibition of gastrointestinal transporter activity had no influence of methadone bioavailability.


2017 ◽  
Vol 62 (2) ◽  
Author(s):  
Michael N. Neely ◽  
Lauren Kato ◽  
Gilmer Youn ◽  
Lironn Kraler ◽  
David Bayard ◽  
...  

ABSTRACT We hypothesized that dosing vancomycin to achieve trough concentrations of >15 mg/liter overdoses many adults compared to area under the concentration-time curve (AUC)-guided dosing. We conducted a 3-year, prospective study of vancomycin dosing, plasma concentrations, and outcomes. In year 1, nonstudy clinicians targeted trough concentrations of 10 to 20 mg/liter (infection dependent) and controlled dosing. In years 2 and 3, the study team controlled vancomycin dosing with BestDose Bayesian software to achieve a daily, steady-state AUC/MIC ratio of ≥400, with a maximum AUC value of 800 mg · h/liter, regardless of trough concentration. For Bayesian estimation of AUCs, we used trough samples in years 1 and 2 and optimally timed samples in year 3. We enrolled 252 adults who were ≥18 years old with ≥1 available vancomycin concentration. Only 19% of all trough concentrations were therapeutic versus 70% of AUCs (P < 0.0001). After enrollment, median trough concentrations by year were 14.4, 9.7, and 10.9 mg/liter (P = 0.005), with 36%, 7%, and 6% over 15 mg/liter (P < 0.0001). Bayesian AUC-guided dosing in years 2 and 3 was associated with fewer additional blood samples per subject (3.6, 2.0, and 2.4; P = 0.003), shorter therapy durations (8.2, 5.4, and 4.7 days; P = 0.03), and reduced nephrotoxicity (8%, 0%, and 2%; P = 0.01). The median inpatient stay was 20 days among nephrotoxic patients versus 6 days (P = 0.002). There was no difference in efficacy by year, with 42% of patients having microbiologically proven infections. Compared to trough concentration targets, AUC-guided, Bayesian estimation-assisted vancomycin dosing was associated with decreased nephrotoxicity, reduced per-patient blood sampling, and shorter length of therapy, without compromising efficacy. These benefits have the potential for substantial cost savings. (This study has been registered at ClinicalTrials.gov under registration no. NCT01932034.)


2010 ◽  
Vol 55 (1) ◽  
pp. 326-330 ◽  
Author(s):  
José Moltó ◽  
Marta Valle ◽  
Cristina Miranda ◽  
Samandhy Cedeño ◽  
Eugenia Negredo ◽  
...  

ABSTRACTThe aim of this open-label, fixed-sequence study was to investigate the potential ofEchinacea purpurea, a commonly used botanical supplement, to interact with the boosted protease inhibitor darunavir-ritonavir. Fifteen HIV-infected patients receiving antiretroviral therapy including darunavir-ritonavir (600/100 mg twice daily) for at least 4 weeks were included.E. purpurearoot extract capsules were added to the antiretroviral treatment (500 mg every 6 h) from days 1 to 14. Darunavir concentrations in plasma were determined by high-performance liquid chromatography immediately before and 1, 2, 4, 6, 8, 10, and 12 h after a morning dose of darunavir-ritonavir on days 0 (darunavir-ritonavir) and 14 (darunavir-ritonavir plus echinacea). Individual darunavir pharmacokinetic parameters were calculated by noncompartmental analysis and compared between days 0 and 14 with the geometric mean ratio (GMR) and its 90% confidence interval (CI). The median age was 49 (range, 43 to 67) years, and the body mass index was 24.2 (range, 18.7 to 27.5) kg/m2. Echinacea was well tolerated, and all participants completed the study. The GMR for darunavir coadministered with echinacea relative to that for darunavir alone was 0.84 (90% CI, 0.63-1.12) for the concentration at the end of the dosing interval, 0.90 (90% CI, 0.74-1.10) for the area under the concentration-time curve from 0 to 12 h, and 0.98 (90% CI, 0.82-1.16) for the maximum concentration. In summary, coadministration ofE. purpureawith darunavir-ritonavir was safe and well tolerated. Individual patients did show a decrease in darunavir concentrations, although this did not affect the overall darunavir or ritonavir pharmacokinetics. Although no dose adjustment is required, monitoring darunavir concentrations on an individual basis may give reassurance in this setting.


2010 ◽  
Vol 54 (7) ◽  
pp. 2965-2973 ◽  
Author(s):  
C. Kityo ◽  
A. S. Walker ◽  
L. Dickinson ◽  
F. Lutwama ◽  
J. Kayiwa ◽  
...  

ABSTRACT We evaluated the pharmacokinetics of lopinavir-ritonavir with and without nonnucleoside reverse transcriptase inhibitors (NNRTIs) in Ugandan adults. The study design was a three-period crossover study (3 tablets [600 mg of lopinavir/150 mg of ritonavir {600/150 mg}], 4 capsules [533/133 mg], and 2 tablets [400/100 mg] twice a day [BD]; n = 40) of lopinavir-ritonavir with NNRTIs and a parallel one-period study (2 tablets BD; n = 20) without NNRTIs. Six-point pharmacokinetic sampling (0, 2, 4, 6, 8, and 12 h) was undertaken after observed intake with a standardized breakfast. Ugandan DART trial participants receiving efavirenz (n = 20), nevirapine (n = 18), and no NNRTI (n = 20) had median ages of 41, 35, and 37 years, respectively, and median weights of 60, 64, and 63 kg, respectively. For the no-NNRTI group, the geometric mean (percent coefficient of variation [%CV]) lopinavir area under the concentration-time curve from 0 to 12 h (AUC0-12) was 110.1 (34%) μg·h/liter. For efavirenz, the geometric mean lopinavir AUC0-12 (%CV) values were 91.8 μg·h/liter (58%), 65.7 μg·h/liter (39%), and 54.0 μg·h/liter (65%) with 3 tablets, 4 capsules, and 2 tablets BD, respectively, with corresponding (within-individual) geometric mean ratios (GMR) for 3 and 2 tablets versus 4 capsules of 1.40 (90% confidence interval [CI], 1.18 to 1.65; P = 0.002) and 0.82 (90% CI, 0.68 to 0.99; P = 0.09), respectively, and the apparent oral clearance (CL/F) values were reduced by 58% and 1%, respectively. For nevirapine, the geometric mean lopinavir AUC0-12 (%CV) values were 112.9 μg·h/liter (30%), 68.1 μg·h/liter (53%), and 61.5 μg·h/liter (52%), respectively, with corresponding GMR values of 1.66 (90% CI, 1.46 to 1.88; P < 0.001) and 0.90 (90% CI, 0.77 to 1.06; P = 0.27), respectively, and the CL/F was reduced by 57% and 7%, respectively. Higher values for the lopinavir concentration at 12 h (C 12) were observed with 3 tablets and efavirenz-nevirapine (P = 0.04 and P = 0.0005, respectively), and marginally lower C 12 values were observed with 2 tablets and efavirenz-nevirapine (P = 0.08 and P = 0.26, respectively). These data suggest that 2 tablets of lopinavir-ritonavir BD may be inadequate when dosed with NNRTIs in Ugandan adults, and the dosage should be increased by the addition of an additional adult tablet or a half-dose tablet (100/25 mg), where available.


2012 ◽  
Vol 56 (10) ◽  
pp. 5076-5081 ◽  
Author(s):  
Keith A. Rodvold ◽  
Mark H. Gotfried ◽  
J. Gordon Still ◽  
Kay Clark ◽  
Prabhavathi Fernandes

ABSTRACTThe steady-state concentrations of solithromycin in plasma were compared with concomitant concentrations in epithelial lining fluid (ELF) and alveolar macrophages (AM) obtained from intrapulmonary samples during bronchoscopy and bronchoalveolar lavage (BAL) in 30 healthy adult subjects. Subjects received oral solithromycin at 400 mg once daily for five consecutive days. Bronchoscopy and BAL were carried out once in each subject at either 3, 6, 9, 12, or 24 h after the last administered dose of solithromycin. Drug concentrations in plasma, ELF, and AM were assayed by a high-performance liquid chromatography-tandem mass spectrometry method. Solithromycin was concentrated extensively in ELF (range of mean [± standard deviation] concentrations, 1.02 ± 0.83 to 7.58 ± 6.69 mg/liter) and AM (25.9 ± 20.3 to 101.7 ± 52.6 mg/liter) in comparison with simultaneous plasma concentrations (0.086 ± 0.070 to 0.730 ± 0.692 mg/liter). The values for the area under the concentration-time curve from 0 to 24 h (AUC0–24values) based on mean and median ELF concentrations were 80.3 and 63.2 mg · h/liter, respectively. The ratio of ELF to plasma concentrations based on the mean and median AUC0–24values were 10.3 and 10.0, respectively. The AUC0–24values based on mean and median concentrations in AM were 1,498 and 1,282 mg · h/L, respectively. The ratio of AM to plasma concentrations based on the mean and median AUC0–24values were 193 and 202, respectively. Once-daily oral dosing of solithromycin at 400 mg produced steady-state concentrations that were significantly (P< 0.05) higher in ELF (2.4 to 28.6 times) and AM (44 to 515 times) than simultaneous plasma concentrations throughout the 24-h period after 5 days of solithromycin administration.


2018 ◽  
Author(s):  
Stephen I Walimbwa ◽  
Mohammed Lamorde ◽  
Catriona Waitt ◽  
Julian Kaboggoza ◽  
Laura Else ◽  
...  

ABSTRACTAcross sub-Saharan Africa, patients with HIV on antiretrovirals often get malaria and need cotreatment with artemisinin-containing therapies. We undertook two pharmacokinetic studies in healthy volunteers, using standard adult doses of artmether-lumefantrine (AL) or artesunate-amodiaquine (AS-AQ) given with 50mg once daily dolutegravir (DTG) to investigate the drug-drug interaction between artmether-lumefantrine or artesunate-amodiaquine and DTG. The DTG/artmether-lumefantrine interaction was evaluated in a two-way cross-over study and measured artemether (ARM), dihydroartemisinin (DHA), lumefantrine (LF), desbutyl-lumefantrine (DBL) over 264h. The DTG/artesunate-amodiaquine interaction was investigated using a parallel study design due to long half-life of the amodiaquine metabolite, desethylamodiaquine (DEAQ) and measured artesunate (ARS), amodiaquine (AQ), DEAQ over 624h. Non-compartmental analysis was performed, and geometric mean ratios and 90% confidence intervals generated for evaluation of both interactions. Dolutegravir did not significantly change the maximum concentration in plasma, time to maximum concentration and area under the concentration-time curve (AUC) for ARM, DHA, LF and DBL nor significantly alter AUC for ARS, DHA, AQ and DEAQ. Co-administration of dolutegravir with AL resulted in a 37% decrease in DTG trough concentrations. Co-administration of dolutegravir with AS-AQ resulted in a decrease of approximately 42% and 24% in DTG trough concentrations and AUC respectively. Study drugs were well-tolerated with no serious adverse events. Standard doses of artmether-lumefantrine and artesunate-amodiaquine should be used in patients receiving DTG. The significant decreases in DTG trough concentrations with artemether-lumefantrine and artesunate-amodiaquine and DTG exposure with artesunate-amodiaquine are unlikely to be of clinical significance as DTG trough concentrations were above DTG target concentrations of 64ng/mL.


2004 ◽  
Vol 48 (11) ◽  
pp. 4328-4331 ◽  
Author(s):  
Robert DiCenzo ◽  
Derick Peterson ◽  
Kim Cruttenden ◽  
Gene Morse ◽  
Garret Riggs ◽  
...  

ABSTRACT Valproic acid (VPA) has the potential to benefit patients suffering from human immunodeficiency virus (HIV)-associated cognitive impairment. The purpose of this study was to determine if VPA affects the plasma concentration of efavirenz (EFV) or lopinavir. HIV type 1 (HIV-1)-infected patients receiving EFV or lopinavir-ritonavir (LPV/r) had 9 or 10 blood samples drawn over 8 to 24 h of a dosing interval at steady state before and after receiving 250 mg of VPA twice daily for 7 days. VPA blood samples drawn before (C 0) and 8 h after the morning dose (8 h) were compared to blood samples from a group of HIV-1-infected subjects who were taking either combined nucleoside reverse transcriptase inhibitors alone or had discontinued antiretroviral therapy. Pharmacokinetic parameters were calculated by noncompartmental analysis, and tests of bioequivalence were based on 90% confidence intervals (CIs) for ratios or differences. The geometric mean ratio (GMR) (90% CI) of the areas under the concentration-time curve from 0 to 24 h (AUC0-24s) of EFV (n = 11) with and without VPA was 1.00 (0.85, 1.17). The GMR (90% CI) of the AUC0-8s of LPV (n = 8) with and without VPA was 1.38 (0.98, 1.94). The differences (90% CI) in mean C 0 and 8-h VPA concentrations versus the control (n = 11) were −1.0 (−9.4, 7.4) μg/ml and −2.1 (−11.1, 6.9) μg/ml for EFV (n = 10) and −5.0 (−13.2, 3.3) μg/ml and −6.7 (−17.6, 4.2) μg/ml for LPV/r (n = 11), respectively. EFV administration alone is bioequivalent to EFV and VPA coadministration. LPV concentrations tended to be higher when the drug was combined with VPA. Results of VPA comparisons fail to raise concern that coadministration with EFV or LPV/r will significantly influence trough concentrations of VPA.


Author(s):  
Michelle Valeria Dias Ferreira Vieira ◽  
José Luiz Fernandes Vieira

Abstract Background Chloroquine is effective against the asexual blood stage of Plasmodium vivax. A high proportion of children are underdosed with the drug, but there are no studies comparing chloroquine exposure in adults and children aged 8–11 years old. The present study intends to compare these populations using the area under the curve (AUC) derived from the plasma concentration-time profile in patients with P. vivax. Methods A prospective study of cases was performed on male children (aged 9–11 years) and adults with vivax malaria. Blood samples were collected after several days of treatment. Chloroquine was measured by high-performance liquid chromatography. A non-compartmental pharmacokinetic model was used to calculate the pharmacokinetic parameters of the drug. Results A total of 20 children and 25 adults were included in the study. Plasma concentrations of chloroquine in older children ranged from 67 to 1112 ng/ml, and in adults the value ranged from 74 to 1147 ng/ml. The AUC to the last measurable concentration and to infinite was significantly lower in children than in adults, indicating a lower exposure to the drug. Conclusion These data demonstrate lower exposure to chloroquine in children, which corroborates the importance of optimising the doses of chloroquine in the study age band to ensure adequate exposure to the drug.


2010 ◽  
Vol 54 (3) ◽  
pp. 1186-1192 ◽  
Author(s):  
Harin A. Karunajeewa ◽  
Sam Salman ◽  
Ivo Mueller ◽  
Francisca Baiwog ◽  
Servina Gomorrai ◽  
...  

ABSTRACT In order to determine the pharmacokinetic disposition of chloroquine (CQ) and its active metabolite, desethylchloroquine (DECQ), when administered as intermittent presumptive treatment in pregnancy (IPTp) for malaria, 30 Papua New Guinean women in the second or third trimester of pregnancy and 30 age-matched nonpregnant women were administered three daily doses of 450 mg CQ (8.5 mg/kg of body weight/day) in addition to a single dose of sulfadoxine-pyrimethamine. For all women, blood was taken at baseline; at 1, 2, 4, 6, 12, 18, 24, 30, 48, and 72 h posttreatment; and at 7, 10, 14, 28, and 42 days posttreatment. Plasma was subsequently assayed for CQ and DECQ by high-performance liquid chromatography, and population pharmacokinetic modeling was performed. Pregnant subjects had significantly lower area under the plasma concentration-time curve for both CQ (35,750 versus 47,892 μg·h/liter, P < 0.001) and DECQ (23,073 versus 41,584 μg·h/liter, P < 0.001), reflecting significant differences in elimination half-lives and in volumes of distribution and clearances relative to bioavailability. Reduced plasma concentrations of both CQ and DECQ could compromise both curative efficacy and posttreatment prophylactic properties in pregnant patients. Higher IPTp CQ doses may be desirable but could increase the risk of adverse hemodynamic effects.


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