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Jadhav SB, Amore BM, Bockbrader H, Crass RL, Chapel S, Sasiela WJ, Emery MG. Population pharmacokinetic and pharmacokinetic-pharmacodynamic modeling of bempedoic acid and low-density lipoprotein cholesterol in healthy subjects and patients with dyslipidemia. J Pharmacokinet Pharmacodyn 2023; 50:351-364. [PMID: 37243877 PMCID: PMC10460718 DOI: 10.1007/s10928-023-09864-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 05/01/2023] [Indexed: 05/29/2023]
Abstract
Population pharmacokinetics (popPK) of bempedoic acid and the popPK/pharmacodynamic (popPK/PD) relationship between bempedoic acid concentrations and serum low-density lipoprotein cholesterol (LDL-C) from baseline were characterized. A two-compartment disposition model with a transit absorption compartment and linear elimination best described bempedoic acid oral pharmacokinetics (PK). Multiple covariates, including renal function, sex, and weight, had statistically significant effects on the predicted steady-state area under the curve. Mild (estimated glomerular filtration rate (eGFR) 60 to < 90 mL/min vs. ≥ 90 mL/min) and moderate (eGFR 30 to < 60 mL/min vs. ≥ 90 mL/min) renal impairment, female sex, low (< 70 kg vs. 70-100 kg) and high (> 100 kg vs. 70-100 kg) body weight were predicted to have a 1.36-fold (90% confidence interval (CI) 1.32, 1.41), 1.85-fold (90% CI 1.74, 2.00), 1.39-fold (90% CI 1.34, 1.47), 1.35-fold (90% CI 1.30, 1.41), and 0.75-fold (90% CI 0.72, 0.79) exposure difference relative to their reference populations, respectively. An indirect response model described changes in serum LDL-C with a model-predicted 35% maximal reduction and bempedoic acid IC50 of 3.17 µg/mL. A 28% reduction from LDL-C baseline was predicted for a steady-state average concentration of 12.5 µg/mL after bempedoic acid (180 mg/day) dosing, accounting for approximately 80% of the predicted maximal LDL-C reduction. Concurrent statin therapy, regardless of intensity, reduced the maximal effect of bempedoic acid but resulted in similar steady-state LDL-C levels. While multiple covariates had statistically significant effects on PK and LDL-C lowering, none were predicted to warrant bempedoic acid dose adjustment.
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Affiliation(s)
- Satyawan B Jadhav
- Ann Arbor Pharmacometrics Group, 900 Victors Way #328, Ann Arbor, MI, 48108, USA
| | - Benny M Amore
- Esperion Therapeutics, Inc., 3891 Ranchero Drive, Suite 150, Ann Arbor, MI, 48108, USA.
| | - Howard Bockbrader
- Ann Arbor Pharmacometrics Group, 900 Victors Way #328, Ann Arbor, MI, 48108, USA
| | - Ryan L Crass
- Ann Arbor Pharmacometrics Group, 900 Victors Way #328, Ann Arbor, MI, 48108, USA
| | - Sunny Chapel
- Ann Arbor Pharmacometrics Group, 900 Victors Way #328, Ann Arbor, MI, 48108, USA
| | - William J Sasiela
- Esperion Therapeutics, Inc., 3891 Ranchero Drive, Suite 150, Ann Arbor, MI, 48108, USA
| | - Maurice G Emery
- Esperion Therapeutics, Inc., 3891 Ranchero Drive, Suite 150, Ann Arbor, MI, 48108, USA
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Amore BM, MacDougall DE, Hanselman JC, Emery MG. Phase 1, Single- and Multiple-Ascending-Dose, Food-Effect, and East Asian Subject Studies to Assess the Pharmacokinetics, Safety, and Tolerability of Bempedoic Acid, a Selective Inhibitor of Adenosine Triphosphate Citrate Lyase. Clin Pharmacol Drug Dev 2023; 12:1022-1035. [PMID: 37477389 DOI: 10.1002/cpdd.1297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 05/23/2023] [Indexed: 07/22/2023]
Abstract
Bempedoic acid is an adenosine triphosphate citrate lyase inhibitor that lowers low-density lipoprotein cholesterol by inhibiting cholesterol synthesis and upregulating hepatic low-density lipoprotein receptor expression. After oral dosing, bempedoic acid was readily absorbed, attaining maximum concentrations with a median time of 3.5 hours, and may be taken without regard to food. Steady-state oral pharmacokinetics in healthy adults receiving bempedoic acid at the approved 180 mg/day dose were characterized by mean maximum concentration of 20.6 µg/mL, area under the concentration-time curve over 24 hours of 289 µg·h/mL, and elimination half-life of 21.1 hours. Multiple-dose pharmacokinetics were linear at bempedoic acid doses of 120-220 mg/day. Circulating concentrations of the active metabolite ESP15228 were 18.0% of bempedoic acid concentrations on average. Comparisons of bempedoic acid 180 mg/day pharmacokinetics after single and multiple dosing revealed no clinically meaningful differences between Japanese, Chinese, and Western subjects. Mean estimates of bempedoic acid elimination half-life in Japanese (25.2 hours) and Chinese (20.0 hours) subjects were comparable to Western subjects (23.9 hours) following 14 days of once-daily dosing. Bempedoic acid was generally safe and well tolerated up to a dose of 220 mg/day across the study populations described herein.
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Amore BM, Patel N, Batheja P, Templeton IE, Jones HM, Louie MJ, Emery MG. Physiologically Based Pharmacokinetic Model Development and Verification for Bioequivalence Testing of Bempedoic Acid Oral Suspension and Reference Tablet Formulation. Pharmaceutics 2023; 15:pharmaceutics15051476. [PMID: 37242718 DOI: 10.3390/pharmaceutics15051476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 04/26/2023] [Accepted: 05/08/2023] [Indexed: 05/28/2023] Open
Abstract
The bioequivalence of bempedoic acid oral suspension and commercial immediate release (IR) tablet formulations were assessed using a physiologically based pharmacokinetic (PBPK) model. The mechanistic model, developed from clinical mass balance results and in vitro intrinsic solubility, permeability, and dissolution data, was verified against observed clinical pharmacokinetics (PK) results. Model inputs included a fraction of a dose in solution (0.01%), viscosity (118.8 cps), and median particle diameter (50 µm) for the suspension and particle diameter (36.4 µm) for IR tablets. Dissolution was determined in the relevant media (pH 1.2-6.8) in vitro. Model simulations of bioequivalence predicted oral suspension (test) to IR tablet (reference) geometric mean ratio estimates of 96.9% (90% confidence interval [CI]: 92.6-101) for maximum concentration and 98.2% (90% CI: 87.3-111) for the area under the concentration-time curve. Sensitivity analyses showed gastric transit time had a minor impact on model predictions. Oral suspension biopharmaceutical safe space was defined by extremes of particle size and the percent of bempedoic acid in solution. PBPK model simulations predicted that the rate and extent of bempedoic acid absorption are unlikely to exhibit clinically meaningful differences when dosed as an oral suspension compared with an IR tablet without requiring a clinical bioequivalence study in adults.
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Affiliation(s)
- Benny M Amore
- Esperion Therapeutics, Inc., Ann Arbor, MI 48108, USA
| | | | - Priya Batheja
- Esperion Therapeutics, Inc., Ann Arbor, MI 48108, USA
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Amore BM, Cramer C, MacDougall D, Emery MG. The Disposition and Metabolism of Bempedoic Acid, A Potent Inhibitor of ATP Citrate Lyase, In Healthy Human Subjects. Drug Metab Dispos 2023; 51:599-609. [PMID: 36878717 DOI: 10.1124/dmd.122.001142] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 01/24/2023] [Accepted: 02/16/2023] [Indexed: 03/08/2023] Open
Abstract
The disposition and metabolism of bempedoic acid, a selective inhibitor of ATP citrate lyase, were examined in healthy male subjects. After a single administration of [14C] bempedoic acid (240 mg, 113 μCi) oral solution, mean concentrations of total radioactivity in plasma as a function of time indicated absorption was rapid with peak concentrations achieved at 1 hour after dose administration. Radioactivity was decreased in a multiexponential fashion with an estimated elimination half-life of 26.0 hours. Radiolabeled dose was predominantly recovered in urine (62.1% of dose) and a smaller amount in feces (25.4% of dose). Bempedoic acid was extensively metabolized with 1.6% to 3.7% of dose excreted unchanged in urine and feces combined. Overall, the major clearance route of bempedoic acid is metabolism by uridine 5'‑diphosphate glucuronosyltransferases. Metabolism in hepatocyte cultures of human and nonclinical species were generally in agreement with clinical metabolite profiles. Pooled plasma samples were characterized by the presence of bempedoic acid, which accounted for 59.3% of total plasma radioactivity, ESP15228 (a reversible keto metabolite of bempedoic acid), and their respective glucuronide conjugates. The acyl glucuronide of bempedoic acid represented 23% to 36% of radioactivity in plasma and accounted for approximately 37% of dose excreted in urine. In feces, the majority of radioactivity was associated with a co-eluting mixture of a carboxylic acid metabolite of bempedoic acid, a taurine conjugate of bempedoic acid and hydroxymethyl-ESP15228, which collectively accounted for 3.1% to 22.9% of bempedoic acid dose across subjects. Significance Statement This study characterizes the disposition and metabolism of bempedoic acid, an inhibitor of ATP citrate lyase for hypercholesterolemia. This work provides further understanding of bempedoic acid clinical pharmacokinetics and clearance pathways in adult subjects.
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Affiliation(s)
- Benny M Amore
- Clinical Pharmacology and Pharmacometrics, Esperion Therapeutics, Inc., United States
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Amore BM, Sasiela WJ, Ries DK, Tresh P, Emery MG. Pharmacokinetics of bempedoic acid in patients with renal impairment. Clin Transl Sci 2021; 15:789-798. [PMID: 34800002 PMCID: PMC8932715 DOI: 10.1111/cts.13202] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/19/2021] [Accepted: 11/03/2021] [Indexed: 02/04/2023] Open
Abstract
Bempedoic acid is an ATP citrate lyase inhibitor approved for the treatment of hypercholesterolemia. The objective of this phase I study was to assess the pharmacokinetics (PKs) and safety of bempedoic acid in 24 subjects with normal renal function or mild, moderate, or severe renal impairment. All subjects received a single oral bempedoic acid 180‐mg dose and PK parameters were monitored for up to 23 days. Resulting estimates of area under the concentration‐time curve exposure following bempedoic acid treatment were 1.5‐fold, 2.2‐fold, and 2.2‐fold higher in subjects with mild, moderate, or severe renal impairment, respectively, compared with subjects with normal renal function. With decreases in renal function, plasma free fraction was increased up to 20.1%, whereas total and unbound clearances were decreased by 55.2% and 62.6%, respectively, in subjects with severe renal impairment relative to those with normal renal function. These observed decreases in total and unbound oral clearance in subjects with decreased renal function are not explained by the increases in free fraction and might therefore also be attributable to changes in bioavailability or intrinsic clearance. Bempedoic acid was generally well‐tolerated and the incidence and type of adverse events were not affected by the degree of renal impairment. In conclusion, bempedoic acid exposures in subjects with renal impairment were increased up to approximately two‐fold with no safety signals identified, consistent with findings in phase III patients with mild or moderate renal impairment. No dose adjustments are necessary for patients with mild or moderate renal impairment.
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Affiliation(s)
- Benny M Amore
- Esperion Therapeutics, Inc., Ann Arbor, Michigan, USA
| | | | - Daniel K Ries
- Nucleus Network, Pty., Ltd., Melbourne, Victoria, Australia
| | - Perry Tresh
- Esperion Therapeutics, Inc., Ann Arbor, Michigan, USA
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Amore BM, Cramer CT, MacDougall DE, Sasiela WJ, Emery MG. Absence of effect of steady state bempedoic acid on cardiac repolarization: Results of a thorough QT/QTc study in healthy volunteers. Clin Transl Sci 2021; 14:2487-2496. [PMID: 34463032 PMCID: PMC8604246 DOI: 10.1111/cts.13116] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 07/01/2021] [Accepted: 07/07/2021] [Indexed: 02/04/2023] Open
Abstract
Bempedoic acid is an inhibitor of adenosine triphosphate–citrate lyase approved for use in adults with hypercholesterolemia. Nonclinical studies assessed binding to the human ether‐a‐go‐go–related gene (hERG) potassium channel in vitro and the effect of bempedoic acid on QT/QTc in cynomolgus monkeys. A randomized, double‐blind, parallel‐design clinical study assessed the effects of steady‐state bempedoic acid at a supratherapeutic dose (240 mg/day, 33.3% higher the180 mg/day therapeutic dose), placebo, and moxifloxacin (400 mg) in healthy subjects. In vitro binding potency for bempedoic acid to the hERG potassium channel was weak, with half‐maximal inhibition (IC50) estimated at greater than 1000 μM (>1670‐fold the bempedoic acid 180 mg/day steady‐state unbound maximum concentration). In monkeys, individual rate‐corrected QT intervals showed no time‐ or dose‐dependent changes up to 100 mg/kg of bempedoic acid. In human subjects, the upper 90% confidence interval (CI) for the difference in QTc interval, corrected using Fridericia’s formula (QTcF), between bempedoic acid and placebo was less than 5 msec at all time points. Concentration‐QTcF analysis showed that maximum bempedoic acid concentration at steady‐state was attained at a median 2.1 h postdose, and the predicted mean change (90% CI) in QTcF at the observed mean bempedoic acid concentration 2 h postdose was −0.5 (−5.0, 4.0) msec. The lower bound of the moxifloxacin 90% CI exceeded 5 msec at prespecified time points, establishing study sensitivity. Steady‐state bempedoic acid at a supratherapeutic dose of 240 mg was generally well‐tolerated and not associated with QTc prolongation in healthy subjects.
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Affiliation(s)
- Benny M Amore
- Esperion Therapeutics, Inc., Ann Arbor, Michigan, USA
| | - Clay T Cramer
- Nonclinical Pharma Solutions, LLC, Dexter, Michigan, USA
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Jadhav SB, Crass RL, Chapel S, Kerschnitzki M, Sasiela WJ, Emery MG, Amore BM, Barrett PHR, Watts GF, Catapano AL. Pharmacodynamic effect of bempedoic acid and statin combinations: predictions from a dose-response model. Eur Heart J Cardiovasc Pharmacother 2021; 8:578-586. [PMID: 34448822 PMCID: PMC9440868 DOI: 10.1093/ehjcvp/pvab064] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 08/03/2021] [Indexed: 02/04/2023]
Abstract
Aims Many patients are unable to achieve guideline-recommended LDL cholesterol (LDL-C) targets, despite taking maximally tolerated lipid-lowering therapy. Bempedoic acid, a competitive inhibitor of ATP citrate lyase, significantly lowers LDL-C with or without background statin therapy in diverse populations. Because pharmacodynamic interaction between statins and bempedoic acid is complex, a dose–response model was developed to predict LDL-C pharmacodynamics following administration of statins combined with bempedoic acid. Methods and results Bempedoic acid and statin dosing and LDL-C data were pooled from 14 phase 1–3 clinical studies. Dose–response models were developed for bempedoic acid monotherapy and bempedoic acid–statin combinations using previously published statin parameters. Simulations were performed using these models to predict change in LDL-C levels following treatment with bempedoic acid combined with clinically relevant doses of atorvastatin, rosuvastatin, simvastatin, and pravastatin. Dose–response models predicted that combining bempedoic acid with the lowest statin dose of commonly used statins would achieve a similar degree of LDL-C lowering as quadrupling that statin dose; for example, the predicted LDL-C lowering was 54% with atorvastatin 80 mg compared with 54% with atorvastatin 20 mg + bempedoic acid 180 mg, and 42% with simvastatin 40 mg compared with 46% with simvastatin 10 mg + bempedoic acid 180 mg. Conclusion These findings suggest bempedoic acid combined with lower statin doses offers similar LDL-C lowering compared with statin monotherapy at higher doses, potentially sparing patients requiring additional lipid-lowering therapies from the adverse events associated with higher statin doses.
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Affiliation(s)
- Satyawan B Jadhav
- Ann Arbor Pharmacometrics Group, 900 Victors Way #328, Ann Arbor, MI 48108, USA
| | - Ryan L Crass
- Ann Arbor Pharmacometrics Group, 900 Victors Way #328, Ann Arbor, MI 48108, USA
| | - Sunny Chapel
- Ann Arbor Pharmacometrics Group, 900 Victors Way #328, Ann Arbor, MI 48108, USA
| | | | - William J Sasiela
- Esperion Therapeutics, Inc., 3891 Ranchero Dr, Ann Arbor, MI 48108, USA
| | - Maurice G Emery
- Esperion Therapeutics, Inc., 3891 Ranchero Dr, Ann Arbor, MI 48108, USA
| | - Benny M Amore
- Esperion Therapeutics, Inc., 3891 Ranchero Dr, Ann Arbor, MI 48108, USA
| | - P Hugh R Barrett
- Faculty of Medicine and Health, University of New England, Armidale, NSW 2351, Australia
| | - Gerald F Watts
- School of Medicine, University of Western Australia, Medical Research Foundation Building, Rear 50 Murray Street, Perth, WA 6001, Australia
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Lee E, Gibbs JP, Emery MG, Block G, Wasserman SM, Hamilton L, Kasichayanula S, Hanafin P, Somaratne R, Egbuna O. Influence of Renal Function on Evolocumab Exposure, Pharmacodynamics, and Safety. Clin Pharmacol Drug Dev 2019; 8:281-289. [PMID: 30676701 PMCID: PMC6590207 DOI: 10.1002/cpdd.650] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 12/03/2018] [Indexed: 12/31/2022]
Abstract
We evaluated the pharmacokinetics, pharmacodynamics, and safety of evolocumab, a fully human monoclonal antibody against proprotein convertase subtilisin kexin type 9 (PCSK9), in an open‐label, parallel‐design study in participants with normal renal function (n = 6), severe renal impairment (RI; n = 6), or end‐stage renal disease (ESRD) receiving hemodialysis (n = 6) who received a single 140‐mg dose of evolocumab. The effects of evolocumab treatment on low‐density lipoprotein cholesterol (LDL‐C) lowering and unbound PCSK9 concentrations were similar in the normal renal function group and the renally impaired groups. Geometric mean Cmax and AUClast values in the severe RI and ESRD hemodialysis groups compared with the normal renal function group were lower but within 37% of the normal renal function group (Jonckheere‐Terpstra trend test; Cmax, P = .23; AUClast, P = .22) and within 26% after adjusting for body weight (mean body weight was approximately 9% higher in the renally impaired groups compared with the normal renal function group). No correlations were observed between exposure and baseline creatinine clearance. No adverse event was determined by the investigators to be related to evolocumab, and there were no trends indicative of clinically important effects on laboratory variables or vital signs. Overall, there were no meaningful differences in evolocumab exposure, as assessed by Cmax and AUClast, in patients with severe RI and ESRD hemodialysis compared with patients with normal renal function, and LDL‐C‐lowering effects were similar across groups. These results support the use of evolocumab without dose adjustment in patients who have severe RI or ESRD.
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Wasserman SM, Sabatine MS, Koren MJ, Giugliano RP, Legg JC, Emery MG, Doshi S, Liu T, Somaratne R, Gibbs JP. Comparison of LDL-C Reduction Using Different Evolocumab Doses and Intervals. J Cardiovasc Pharmacol Ther 2018; 23:423-432. [DOI: 10.1177/1074248418774043] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Background: The proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor evolocumab reduces low-density lipoprotein cholesterol (LDL-C) and the risk of cardiovascular events. Objectives: To compare LDL-C reduction using evolocumab 140 mg once every 2 weeks (Q2W) or 420 mg monthly (QM) versus lower doses (70 mg Q2W or 280 mg QM) or placebo. Methods: Patients received evolocumab 70 or 140 mg Q2W, 280 or 420 mg QM, or placebo Q2W or QM in two 12-week phase 2 studies: one with and one without statins. Changes from baseline in LDL-C were compared across Q2W doses and across QM doses. Results: The analysis included 741 patients. Mean (95% confidence interval [CI]) reduction in LDL-C across Q2W visits through week 12 was 63.0% (60.3% to 65.7%) for evolocumab 140 mg Q2W, compared to 41.3% (38.6% to 44.0%) for 70 mg Q2W and 1.9% (4.6% reduction to 0.8% increase) for placebo Q2W (each P < .001 vs 140 mg Q2W), and 62.7% (60.1% to 65.3%) for 420 mg QM, compared to 55.5% (52.9% to 58.0%) for 280 mg QM and 2.5% (5.1% reduction to 0.1% increase) for placebo QM (each P < .001 vs 420 mg QM). Similar results were observed at the mean of weeks 10 and 12. In a subgroup (n = 151) with weekly assessments from weeks 8 to 12, mean (95% CI) peak effect on LDL-C reduction was 72.8% (67.7% to 77.9%) for 140 mg Q2W and 69.0% (63.6% to 74.3%) for 420 mg QM. Trough effect at week 12 underestimated LDL-C reduction. Median peak–trough variability was 20.5%, 21.1%, 31.9%, and 35.1% for evolocumab 140 mg Q2W, 420 mg QM, 70 mg Q2W, and 280 mg QM, respectively. Conclusion: Evolocumab 140 mg Q2W and 420 mg QM yielded similar LDL-C reduction. These doses sustained maximal LDL-C reduction, resulting in greater stability in LDL-C reduction over the dosing interval compared to lower doses. These results support evolocumab doses of either 140 mg Q2W or 420 mg QM.
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Affiliation(s)
| | - Marc S. Sabatine
- Division of Cardiovascular Medicine, Thrombolysis in Myocardial Infarction (TIMI) Study Group, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA
| | - Michael J. Koren
- Jacksonville Center for Clinical Research, Jacksonville, FL, USA
| | - Robert P. Giugliano
- Division of Cardiovascular Medicine, Thrombolysis in Myocardial Infarction (TIMI) Study Group, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA
| | - Jason C. Legg
- Global Biostatistical Science, Amgen Inc, Thousand Oaks, CA, USA
| | | | - Sameer Doshi
- Clinical Pharmacology, Amgen Inc, Thousand Oaks, CA, USA
| | - Thomas Liu
- Global Biostatistical Science, Amgen Inc, Thousand Oaks, CA, USA
| | | | - John P. Gibbs
- Clinical Pharmacology, Amgen Inc, Thousand Oaks, CA, USA
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Kuchimanchi M, Grover A, Emery MG, Somaratne R, Wasserman SM, Gibbs JP, Doshi S. Population pharmacokinetics and exposure-response modeling and simulation for evolocumab in healthy volunteers and patients with hypercholesterolemia. J Pharmacokinet Pharmacodyn 2018; 45:505-522. [PMID: 29736889 PMCID: PMC5953983 DOI: 10.1007/s10928-018-9592-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 04/24/2018] [Indexed: 12/27/2022]
Abstract
Evolocumab, a novel human monoclonal antibody, inhibits proprotein convertase subtilisin/kexin type 9, a protein that targets low-density lipoprotein-cholesterol (LDL-C) receptors for the treatment of hyperlipidemia. The primary objective of this analysis was to characterize the population pharmacokinetics (popPK) and exposure-response relationship of evolocumab to assess if dose adjustment is needed across differing patient populations. Data were pooled for 5474 patients in 11 clinical studies who received evolocumab doses of 7-420 mg at various frequencies, either intravenously or subcutaneously. Evolocumab area under concentration-time curve from 8 to 12 weeks (AUCwk8-12) was simulated for individuals using the popPK model and was used to predict the LDL-C response in relation to AUCwk8-12. Evolocumab was eliminated through nonspecific (linear) and target-mediated (nonlinear) clearance. PopPK parameters and associated variabilities of evolocumab were similar to those of other monoclonal antibodies. The exposure-response model predicted a maximal 66% reduction in LDL-C from baseline to the mean of weeks 10 and 12 for doses of evolocumab 140 mg subcutaneously every 2 weeks or 420 mg subcutaneously once monthly. After inclusion of statistically significant covariates in an uncertainty-based simulation, LDL-C reduction from baseline at the mean of weeks 10 and 12 was predicted to be within 74% to 126% of the reference patient for all simulated patient groups. Evolocumab had nonlinear pharmacokinetics. The range of responses based on intrinsic and extrinsic factors was not predicted to be sufficiently different from the reference patient to warrant evolocumab dose adjustment.
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Affiliation(s)
| | - Anita Grover
- Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, USA
| | | | | | | | - John P Gibbs
- Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, USA
| | - Sameer Doshi
- Amgen Inc., One Amgen Center Dr, Thousand Oaks, CA, USA.
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Hovland DN, Boyd RB, Butt MT, Engelhardt JA, Moxness MS, Ma MH, Emery MG, Ernst NB, Reed RP, Zeller JR, Gash DM, Masterman DM, Potter BM, Cosenza ME, Lightfoot RM. Six-Month Continuous Intraputamenal Infusion Toxicity Study of Recombinant Methionyl Human Glial Cell Line-Derived Neurotrophic Factor (r-metHuGDNF) in Rhesus Monkeys. Toxicol Pathol 2017. [DOI: 10.1177/01926230701481899a] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Recombinant human glial cell line-derived neurotrophic factor (r-metHuGDNF) is a potent neuronal growth and survival factor that has been considered for clinical use in the treatment of Parkinson’s disease (PD). Here we present results of a 6-month toxicology study in rhesus monkeys conducted to support clinical evaluation of chronic intraputamenal infusion of r-metHuGDNF for PD. Monkeys (6–9/sex/group) were treated with 0 (vehicle), 15, 30, or 100 μg/day r-metHuGDNF by continuous unilateral intraputamenal infusion (150 μl/day flow rate) for 6 months; a subset of animals (2–3/sex/group) underwent a subsequent 3-month treatment-free recovery period. Notable observations included reduced food consumption and body weight at 100 μg/day and meningeal thickening underlying the medulla oblongata and/or overlying various spinal cord segments at 30 and 100 μg/day. In addition, multifocal cerebellar Purkinje cell loss (with associated atrophy of the molecular layer and, in some cases, granule cell loss) was observed in 4 monkeys in the 100-μg/day group. This cerebellar finding has not been observed in previous nonclinical studies evaluating r-metHuGDNF. The small number of affected animals precludes definitive conclusions regarding the pathogenesis of the cerebellar lesion, but the data support an association with r-metHuGDNF treatment.
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Affiliation(s)
| | - Robert B. Boyd
- Northern Biomedical Research, Inc., Muskegon, Michigan 49441
| | - Mark T. Butt
- Pathology Associates, Charles River Laboratories, Frederick, Maryland 21701
| | | | | | - Mark H. Ma
- Amgen Inc., Thousand Oaks, California 91320
| | | | | | - Randall P. Reed
- Northern Biomedical Research, Inc., Muskegon, Michigan 49441
| | | | - Don M. Gash
- Anatomy and Neurobiology, University of Kentucky, Lexington, Kentucky 40536
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Gibbs JP, Doshi S, Kuchimanchi M, Grover A, Emery MG, Dodds MG, Gibbs MA, Somaratne R, Wasserman SM, Blom D. Impact of Target-Mediated Elimination on the Dose and Regimen of Evolocumab, a Human Monoclonal Antibody Against Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9). J Clin Pharmacol 2016; 57:616-626. [PMID: 27861991 PMCID: PMC5412926 DOI: 10.1002/jcph.840] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 10/11/2016] [Indexed: 01/14/2023]
Abstract
Understanding the pharmacokinetic (PK) and pharmacodynamic (PD) relationship of a therapeutic monoclonal antibody against proprotein convertase subtilisin/kexin type 9 (PCSK9) exhibiting target-mediated drug disposition (TMDD) is critical for selecting optimal dosing regimens. We describe the PK/PD relationship of evolocumab using a mathematical model that captures evolocumab binding and removal of unbound PCSK9 as well as reduction in circulating low-density lipoprotein cholesterol (LDL-C). Data were pooled from 2 clinical studies: a single-dose escalation study in healthy subjects (7-420 mg SC; n = 44) and a multiple-dose escalation study in statin-treated hypercholesterolemic patients (14 mg weekly to 420 mg monthly [QM] SC; n = 57). A TMDD model described the time course of unbound evolocumab concentrations and removal of unbound PCSK9. The estimated linear clearance and volume of evolocumab were 0.256 L/day and 2.66 L, respectively, consistent with other monoclonal antibodies. The time course of LDL-C reduction was described by an indirect response model with the elimination rate of LDL-C being modulated by unbound PCSK9. The concentration of unbound PCSK9 associated with half-maximal inhibition (IC50 ) of LDL-C elimination was 1.46 nM. Based on simulations, 140 mg every 2 weeks (Q2W) and 420 mg QM were predicted to achieve a similar time-averaged effect of 69% reduction in LDL-C in patients on statin therapy, suggesting that an approximate 3-fold dose increase is required for a 2-fold extension in the dosing interval. Evolocumab dosing regimens of 140 mg Q2W or 420 mg QM were predicted to result in comparable reductions in LDL-C over a monthly period, consistent with results from recently completed phase 3 studies.
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Affiliation(s)
- John P Gibbs
- Amgen Inc, Thousand Oaks, CA, USA.,Current affiliation: AbbVie, North Chicago, IL, USA
| | | | | | - Anita Grover
- Amgen Inc, Thousand Oaks, CA, USA.,Current affiliation: BioMarin Pharmaceuticals, Novato, CA, USA
| | | | - Michael G Dodds
- Amgen Inc, Thousand Oaks, CA, USA.,Current affiliation: Quantitative Solutions, a Certara Company, Seattle, WA, USA
| | - Megan A Gibbs
- Amgen Inc, Thousand Oaks, CA, USA.,Current affiliation: BioMarin Pharmaceuticals, Novato, CA, USA
| | | | | | - Dirk Blom
- Division of Lipidology, Department of Medicine, University of Cape Town, Cape Town, South Africa
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Gibbs JP, Slatter JG, Egbuna O, Geller M, Hamilton L, Dias CS, Xu RY, Johnson J, Wasserman SM, Emery MG. Evaluation of Evolocumab (AMG 145), a Fully Human Anti-PCSK9 IgG2 Monoclonal Antibody, in Subjects With Hepatic Impairment. J Clin Pharmacol 2016; 57:513-523. [PMID: 27667740 PMCID: PMC5363371 DOI: 10.1002/jcph.832] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 09/22/2016] [Indexed: 11/11/2022]
Abstract
Evolocumab binds PCSK9, increasing low-density lipoprotein cholesterol (LDL-C) receptors and lowering LDL-C. Target-mediated evolocumab elimination is attributable to PCSK9 binding. As circulating PCSK9 and LDL-C levels are primarily regulated by the liver, we compared evolocumab pharmacokinetics, pharmacodynamics, and safety in individuals with and without hepatic impairment. An open-label, parallel-group study evaluated the pharmacokinetics of evolocumab in hepatic-impaired (Child-Pugh Class A or B) or healthy adults. Participants were classified as having no, mild, or moderate hepatic impairment (n = 8/group) and received a single 140-mg evolocumab dose. Assessments of unbound evolocumab and PCSK9 were made predose and postdose. Adverse events were monitored throughout the study. No significant association was observed between baseline PCSK9 and increasing level of hepatic impairment. No difference in extent and time course of PCSK9 or LDL-C reduction was observed despite an apparent decrease in mean unbound evolocumab exposure with increasing hepatic impairment (Jonckheere-Terpstra trend test; maximum serum concentration P = .18; area under the curve P = .09). Maximum reductions were observed in moderately impaired subjects vs healthy individuals: mean maximum serum concentration -34%; mean area under the concentration-time curve (AUC) -47%. On average, unbound PCSK9 serum concentrations fell by >80% at 4 hours after a single evolocumab dose. Mean (95% confidence interval) maximum LDL-C reductions in the healthy, mild, and moderate groups were -57% (-64% to -48%), -70% (-75% to -63%), and -53% (-61% to -43%), respectively. No safety risks were identified. These results support evolocumab use without dose adjustment in patients with active liver disease and mild or moderate hepatic impairment.
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Affiliation(s)
- John P Gibbs
- Medical Sciences, Amgen, Inc., Thousand Oaks, CA, USA.,AbbVie, North Chicago, IL, USA
| | - J Greg Slatter
- Medical Sciences, Amgen, Inc., Thousand Oaks, CA, USA.,Acerta Pharma, Bellevue, WA, USA
| | - Ogo Egbuna
- Medical Sciences, Amgen, Inc., Thousand Oaks, CA, USA
| | | | - Lisa Hamilton
- Biostatistics-Internationals, Amgen, Inc., Uxbridge, UK
| | - Clapton S Dias
- Medical Sciences, Amgen, Inc., Thousand Oaks, CA, USA.,BioMarin Pharmaceutical Inc., San Rafael, CA, USA
| | - Ren Y Xu
- Medical Sciences, Amgen, Inc., Thousand Oaks, CA, USA.,Gilead Science Inc., Foster City, CA, USA
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Hovland DN, Boyd RB, Butt MT, Engelhardt JA, Moxness MS, Ma MH, Emery MG, Ernst NB, Reed RP, Zeller JR, Gash DM, Masterman DM, Potter BM, Cosenza ME, Lightfoot RM. Reprint: Six-Month Continuous Intraputamenal Infusion Toxicity Study of Recombinant Methionyl Human Glial Cell Line-Derived Neurotrophic Factor (r-metHuGDNF) in Rhesus Monkeys. Toxicol Pathol 2016; 35:1013-29. [PMID: 18098052 DOI: 10.1177/01926230701481899] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Recombinant human glial cell line-derived neurotrophic factor (r-metHuGDNF) is a potent neuronal growth and survival factor that has been considered for clinical use in the treatment of Parkinson’s disease (PD). Here we present results of a 6-month toxicology study in rhesus monkeys conducted to support clinical evaluation of chronic intraputamenal infusion of r-metHuGDNF for PD. Monkeys (6–9/sex/group) were treated with 0 (vehicle), 15, 30, or 100 μg/day r-metHuGDNF by continuous unilateral intraputamenal infusion (150 μl/day flow rate) for 6 months; a subset of animals (2–3/sex/group) underwent a subsequent 3-month treatment-free recovery period. Notable observations included reduced food consumption and body weight at 100 μg/day and meningeal thickening underlying the medulla oblongata and/or overlying various spinal cord segments at 30 and 100 μg/day. In addition, multifocal cerebellar Purkinje cell loss (with associated atrophy of the molecular layer and, in some cases, granule cell loss) was observed in 4 monkeys in the 100-μg/day group. This cerebellar finding has not been observed in previous nonclinical studies evaluating r-metHuGDNF. The small number of affected animals precludes definitive conclusions regarding the pathogenesis of the cerebellar lesion, but the data support an association with r-metHuGDNF treatment.
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Affiliation(s)
| | - Robert B. Boyd
- Northern Biomedical Research, Inc., Muskegon, Michigan 49441
| | - Mark T. Butt
- Pathology Associates, Charles River Laboratories, Frederick, Maryland 21701
| | | | | | - Mark H. Ma
- Amgen Inc., Thousand Oaks, California 91320
| | | | | | - Randall P. Reed
- Northern Biomedical Research, Inc., Muskegon, Michigan 49441
| | | | - Don M. Gash
- Anatomy and Neurobiology, University of Kentucky, Lexington, Kentucky 40536
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Gao Q, Kimura RE, Zhang X, Nam J, Amore BM, Hickman D, Greg Slatter J, Emery MG. Intestinal and hepatic first-pass extraction of the 11β-HSD1 inhibitor AMG 221 in rats with chronic vascular catheters. Xenobiotica 2013; 44:264-9. [PMID: 23517558 DOI: 10.3109/00498254.2013.769074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
1. A catheterized rat model was used to define the intestinal and hepatic components of oral bioavailability for an 11β-HSD1 inhibitor, AMG 221. These data were integrated with standard in vivo metabolism studies to elucidate the components contributing to the oral disposition of a novel drug candidate. 2. Intestinal and hepatic extraction ratios of AMG 221 obtained using a five-catheter rat model were 0.56 and 0.32, respectively. Therefore, both intestinal and hepatic extraction contributed to the first-pass component of oral bioavailability. There was no evidence for significant gut extraction of systemically administered drug. 3. Mass balance data and in vivo metabolite characterization obtained after administration of [(14)C] AMG 221 to rat showed that AMG 221 was completely absorbed from the gut lumen following an oral dose, primarily excreted in urine and was almost completely metabolized prior to excretion. 4. Hepatic bioavailability (FH), measured in two animals at various time points after oral dose administration was somewhat variable but generally characterized by an initial reduction during the absorption phase followed by an increase during the elimination phase, consistent with hepatic distribution of AMG 221. 5. The five-catheter rat model afforded estimates of hepatic and intestinal contribution to oral bioavailability that were used with other data to define the preclinical ADME characteristics of a drug candidate.
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Affiliation(s)
- Qiuxia Gao
- Department of Pharmacokinetics and Drug Metabolism, Amgen Inc. , Seattle, WA , USA and
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Gibbs JP, Emery MG, McCaffery I, Smith B, Gibbs MA, Akrami A, Rossi J, Paweletz K, Gastonguay MR, Bautista E, Wang M, Perfetti R, Daniels O. Population Pharmacokinetic/Pharmacodynamic Model of Subcutaneous Adipose 11β-Hydroxysteroid Dehydrogenase Type 1 (11β-HSD1) Activity After Oral Administration of AMG 221, a Selective 11β-HSD1 Inhibitor. J Clin Pharmacol 2013; 51:830-41. [DOI: 10.1177/0091270010374470] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Zhu X, Slatter JG, Emery MG, Deane MR, Akrami A, Zhang X, Hickman D, Skiles GL, Subramanian R. Activity-based exposure comparisons among humans and nonclinical safety testing species in an extensively metabolized drug candidate. Xenobiotica 2012; 43:617-27. [DOI: 10.3109/00498254.2012.747711] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Dias CS, Shaywitz AJ, Wasserman SM, Smith BP, Gao B, Stolman DS, Crispino CP, Smirnakis KV, Emery MG, Colbert A, Gibbs JP, Retter MW, Cooke BP, Uy ST, Matson M, Stein EA. Effects of AMG 145 on low-density lipoprotein cholesterol levels: results from 2 randomized, double-blind, placebo-controlled, ascending-dose phase 1 studies in healthy volunteers and hypercholesterolemic subjects on statins. J Am Coll Cardiol 2012; 60:1888-98. [PMID: 23083772 DOI: 10.1016/j.jacc.2012.08.986] [Citation(s) in RCA: 189] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 08/08/2012] [Accepted: 08/30/2012] [Indexed: 12/12/2022]
Abstract
OBJECTIVES The aim of this study was to evaluate the safety, tolerability, and effects of AMG 145 on low-density lipoprotein cholesterol (LDL-C) in healthy and hypercholesterolemic subjects on statin therapy. BACKGROUND Proprotein convertase subtilisin/kexin type 9 (PCSK9) down-regulates surface expression of the low-density lipoprotein receptor (LDL-R), increasing serum LDL-C. AMG 145, a fully human monoclonal antibody to PCSK9, prevents PCSK9/LDL-R interaction, restoring LDL-R recycling. METHODS Healthy adults (phase 1a) were randomized to 1 dose of AMG 145: 7, 21, 70, 210, or 420 mg SC; 21 or 420 mg IV; or matching placebo. Hypercholesterolemic adults (phase 1b) receiving low- to moderate-dose statins were randomized to multiple SC doses of AMG 145: 14 or 35 mg once weekly (QW) ×6, 140 or 280 mg every 2 weeks (Q2W) ×3, 420 mg every 4 weeks ×2, or matching placebo. Eleven subjects receiving high-dose statins and 6 subjects with heterozygous familial hypercholesterolemia were randomized to SC AMG 145 140 mg or placebo Q2W ×3. RESULTS In the trials (AMG 145 n = 85, placebo n = 28), AMG 145 reduced LDL-C up to 64% (p < 0.0001) versus placebo after 1 dose ≥21 mg and up to 81% (p < 0.001) with repeated doses ≥35 mg QW. No serious adverse events (AEs) occurred. Overall incidence of treatment-emergent AEs was similar in AMG 145 versus placebo groups: 69% versus 71% (phase 1a); 65% versus 64% (phase 1b). CONCLUSIONS In phase 1 studies, AMG 145 significantly reduced serum LDL-C in healthy and hypercholesterolemic statin-treated subjects, including those with heterozygous familial hypercholesterolemia or taking the highest doses of atorvastatin or rosuvastatin, with an overall AE profile similar to placebo.
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Affiliation(s)
- Clapton S Dias
- Medical Sciences, Amgen, One Amgen Center Drive, Thousand Oaks, California 91320-1799, USA.
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Foti RS, Pearson JT, Wong SL, Zalikowski JA, Boudreaux MD, Prokop SP, Davis JA, Banfield C, Emery MG, Rock DA, Wahlstrom JL, Wienkers LC, Amore BM. Predicting the Drug Interaction Potential of AMG 853, a Dual Antagonist of the D-Prostanoid and Chemoattractant Receptor-Homologous Molecule Expressed on T Helper 2 Cells Receptors. Drug Metab Dispos 2012; 40:2239-49. [DOI: 10.1124/dmd.112.047928] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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20
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Greene RJ, Davis JA, Subramanian R, Deane MR, Emery MG, Slatter JG. Regiospecific and stereospecific triangulation of the structures of metabolites formed by sequential metabolism at multiple prochiral centers. Drug Metab Dispos 2012; 40:928-42. [PMID: 22328582 DOI: 10.1124/dmd.111.043166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Structures of in vivo secondary metabolites of a norbornane-containing drug candidate with multiple prochiral centers were triangulated, in a regio- and stereospecific fashion, using in vitro metabolism data from synthetic primary metabolites and in vivo metabolism data from the separate administration of a radiolabeled primary metabolite, [(14)C]-(S)-2-((1R,2S,4R,5S)-5-hydroxybicyclo[2.2.1]heptan-2-ylamino)-5-isopropyl-5-methylthiazol-4(5H)-one (M1). A mass balance study on the 11β hydroxysteroid dehydrogenase type 1 enzyme inhibitor [(14)C]-(S)-2-((1S,2S,4R)-bicyclo[2.2.1]heptan-2-ylamino)-5-isopropyl-5-methylthiazol-4(5H)-one (AMG 221) in rats was dosed at 2 mg/kg. Radioactivity was excreted mainly in urine. Metabolites of AMG 221 were quantified by high-performance liquid chromatography with radiometric detection and characterized by liquid chromatography-tandem mass spectrometry (LC-MS/MS). LC-MS/MS revealed at least 38 metabolites. Seven monohydroxylated metabolites mediated formation of the other 31 metabolites. Twenty-eight metabolites were identified regio- and stereo-specifically. Little parent drug was observed in urine or feces. Monohydroxy metabolite M1 was the major metabolite comprising 17 to 24% of excreted dose, and seven monohydroxy metabolites comprised 29 (male) and 37% (female) of dose. Of 11 quantifiable isobaric dihydroxy metabolites that comprised 8.3 (male) and 24% (female) of dose, 10 were identified regio- and stereospecifically by triangulation. A single trihydroxy metabolite comprised approximately 10% of dose. Complex secondary metabolism of drugs with multiple prochiral centers can be elucidated in a regio- and stereospecific fashion without NMR through synthesis and in vitro and in vivo studies on the metabolism of chiral primary oxidation products.
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Affiliation(s)
- Robert J Greene
- Pharmacokinetics and Drug Metabolism, Amgen Inc., 1201 Amgen Court West, Seattle, Washington 98119, USA
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Li A, Yuan CC, Chow D, Chen M, Emery MG, Hale C, Zhang X, Subramanian R, St. Jean DJ, Komorowski R, Véniant M, Wang M, Fotsch C. Synthesis and Evaluation of the Metabolites of AMG 221, a Clinical Candidate for the Treatment of Type 2 Diabetes. ACS Med Chem Lett 2011; 2:824-7. [PMID: 24900270 DOI: 10.1021/ml2001467] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2011] [Accepted: 09/13/2011] [Indexed: 11/30/2022] Open
Abstract
All eight of the major active metabolites of (S)-2-((1S,2S,4R)-bicyclo[2.2.1]heptan-2-ylamino)-5-isopropyl-5-methylthiazol-4(5H)-one (AMG 221, compound 1), an inhibitor of 11β-hydroxysteroid dehydrogenase type 1 that has entered the clinic for the treatment of type 2 diabetes, were synthetically prepared and confirmed by comparison with samples generated in liver microsomes. After further profiling, we determined that metabolite 2 was equipotent to 1 on human 11β-HSD1 and had lower in vivo clearance and higher bioavailability in rat and mouse. Compound 2 was advanced into a pharmacodynamic model in mouse where it inhibited adipose 11β-HSD1 activity.
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Affiliation(s)
- Aiwen Li
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - Chester C. Yuan
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - David Chow
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - Michelle Chen
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - Maurice G. Emery
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - Clarence Hale
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - Xiping Zhang
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - Raju Subramanian
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - David J. St. Jean
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - Renee Komorowski
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - Murielle Véniant
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - Minghan Wang
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
| | - Christopher Fotsch
- Departments of Chemistry Research and Discovery, ‡Metabolic Disorders, and §Pharmacokinetics and Drug Metabolism, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States
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Amore BM, Gibbs JP, Emery MG. Application of in vivo animal models to characterize the pharmacokinetic and pharmacodynamic properties of drug candidates in discovery settings. Comb Chem High Throughput Screen 2010; 13:207-18. [PMID: 20053166 DOI: 10.2174/138620710790596808] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2009] [Accepted: 06/15/2009] [Indexed: 11/22/2022]
Abstract
A goal of preclinical discovery is the identification of drug candidates suitable for clinical testing. Successful integration of in vitro and in vivo experimental data sets can afford projections of human dose regimens anticipated to be safe and therapeutically beneficial. While in vitro experiments guide new chemical syntheses and are essential to understanding drug action and disposition, in vivo characterizations provide unique insight into complex biological systems that control concentrations at the site of action and pharmacologic response. Pharmacokinetic and pharmacodynamic (PK/PD) concepts underlying drug disposition and response provide a quantitative framework with which to identify potential clinical candidates. To improve throughput in earlier stages of drug discovery, in vivo pharmacokinetic study designs such as cassette dosing and sparse sampling schemes have been utilized. In later stages of discovery, pharmacokinetic studies using chemical inhibitors or surgical and genetic animal models are used to characterize the underlying determinants of drug disposition. In a complimentary fashion, modeling of in vivo pharmacodynamic effects may quantitatively link biomarkers to pharmacological response, validate in vitro to in vivo correlations and underwrite predictions of efficacious exposure targets. When applied to in vivo discovery data, PK/PD models have aided in understanding mechanisms of pharmacological response such as receptor theory in the central nervous system and cell turnover concepts in infectious disease and oncology. This review considers the role of in vivo testing toward understanding the pharmacokinetic and pharmacodynamic attributes of lead candidates in drug discovery.
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Affiliation(s)
- Benny M Amore
- Amgen, Inc., Department of Pharmacokinetics and Drug Metabolism, 2101 Amgen Court West, Seattle, WA 98119, USA.
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Véniant MM, Hale C, Hungate RW, Gahm K, Emery MG, Jona J, Joseph S, Adams J, Hague A, Moniz G, Zhang J, Bartberger MD, Li V, Syed R, Jordan S, Komorowski R, Chen MM, Cupples R, Kim KW, St. Jean DJ, Johansson L, Henriksson MA, Williams M, Vallgårda J, Fotsch C, Wang M. Discovery of a Potent, Orally Active 11β-Hydroxysteroid Dehydrogenase Type 1 Inhibitor for Clinical Study: Identification of (S)-2-((1S,2S,4R)-Bicyclo[2.2.1]heptan-2-ylamino)-5-isopropyl-5-methylthiazol-4(5H)-one (AMG 221). J Med Chem 2010; 53:4481-7. [DOI: 10.1021/jm100242d] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Hovland DN, Boyd RB, Butt MT, Engelhardt JA, Moxness MS, Ma MH, Emery MG, Ernst NB, Reed RP, Zeller JR, Gash DM, Masterman DM, Potter BM, Cosenza ME, Lightfoot RM. Six-Month Continuous Intraputamenal Infusion Toxicity Study of Recombinant Methionyl Human Glial Cell Line-Derived Neurotrophic Factor (r-metHuGDNF) in Rhesus Monkeys. Toxicol Pathol 2007; 35:676-92. [PMID: 17763282 DOI: 10.1080/01926230701481899] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Recombinant human glial cell line-derived neurotrophic factor (r-metHuGDNF) is a potent neuronal growth and survival factor that has been considered for clinical use in the treatment of Parkinson's disease (PD). Here we present results of a 6-month toxicology study in rhesus monkeys conducted to support clinical evaluation of chronic intraputamenal infusion of r-metHuGDNF for PD. Monkeys (6-9/sex/group) were treated with 0 (vehicle), 15, 30, or 100 micro g/day r-metHuGDNF by continuous unilateral intraputamenal infusion (150 micro l/day flow rate) for 6 months; a subset of animals (2-3/sex/group) underwent a subsequent 3-month treatment-free recovery period. Notable observations included reduced food consumption and body weight at 100 micro g/day and meningeal thickening underlying the medulla oblongata and/or overlying various spinal cord segments at 30 and 100 micro g/day. In addition, multifocal cerebellar Purkinje cell loss (with associated atrophy of the molecular layer and, in some cases, granule cell loss) was observed in 4 monkeys in the 100-micro g/day group. This cerebellar finding has not been observed in previous nonclinical studies evaluating r-metHuGDNF. The small number of affected animals precludes definitive conclusions regarding the pathogenesis of the cerebellar lesion, but the data support an association with r-metHuGDNF treatment.
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Emery MG, Fisher JM, Chien JY, Kharasch ED, Dellinger EP, Kowdley KV, Thummel KE. CYP2E1 activity before and after weight loss in morbidly obese subjects with nonalcoholic fatty liver disease. Hepatology 2003; 38:428-35. [PMID: 12883487 DOI: 10.1053/jhep.2003.50342] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Previous studies suggest that hepatic cytochrome P450 2E1 (CYP2E1) activity is increased in individuals with chronic alcoholism, nonalcoholic steatohepatitis (NASH), and morbid obesity, and may contribute to liver disease. We studied 16 morbidly obese subjects with varying degrees of hepatic steatosis and 16 normal-weight controls. Obese subjects were evaluated at baseline, 6 weeks, and 1 year after gastroplasty, a procedure that leads to weight loss. Hepatic CYP2E1 activity was assessed by determination of the clearance of chlorzoxazone (CLZ), an in vivo CYP2E1-selective probe. Liver biopsy tissue was obtained during surgery for histopathology. Both the total and unbound oral CLZ clearance (Cl(u)/F) was elevated approximately threefold in morbidly obese subjects compared with controls (P <.001). The Cl(u)/F was significantly higher among subjects with steatosis involving >50% of hepatocytes, compared with those with steatosis in < or =50% of hepatocytes (P =.02). At postoperative week 6 and year 1, the median body mass index (BMI) of subjects who underwent gastroplasty decreased by 11% and 33%, total oral CLZ clearance declined by 16% (P <.01) and 46% (P <.05), and Cl(u)/F decreased by 18% (P <.05) and 35% (P =.16), respectively. Moreover, those subjects with a year 1 BMI <30 kg/m(2) exhibited a median Cl(u)/F that was 63% lower (P =.02) than the respective clearance for all other subjects. In conclusion, hepatic CYP2E1 activity is up-regulated in morbidly obese subjects. A positive association between the degree of steatosis and CYP2E1 activity preoperatively and between the extent of obesity and CYP2E1 activity postoperatively, suggests that CYP2E1 induction is related to or caused by hepatic pathology that results from morbid obesity.
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Affiliation(s)
- Maurice G Emery
- Department of Pharmaceutics, University of Washington, Seattle, WA 98195, USA
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De Lia JE, Kuhlmann RS, Emery MG. Maternal metabolic abnormalities in twin-to-twin transfusion syndrome at mid-pregnancy. Twin Res 2000; 3:113-7. [PMID: 10918625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
We report abnormal maternal laboratory parameters in twin-to-twin transfusion syndrome (TTTS) at mid-pregnancy. A retrospective chart review was undertaken of 109 patients with TTTS evaluated for placental laser surgery. Complete blood count (CBC), blood type and Rh factor, urine analysis and serum chemistry panel were obtained preoperatively, with the CBC and serum albumin repeated on the first postoperative day. The mean gestational age was 21.2+/-1.7 weeks. Initial abnormal values included hematocrit (32.1+/-3.0%), hemoglobin (11.0+/-1.03 g/dl), serum magnesium (1.71+/-0.17 mg/dl), total protein (6.08+/-0.55 g/dl) and albumin (3.06+/-0.34 g/dl). Despite minimal blood loss and conservative fluid replacement mean hematocrit, hemoglobin, and albumin were 27.3+/-2.74%, 9.3+/-0.94 g/dl and 2.56+/-0.23 g/dl, respectively on postoperative day one. Weight gain (8.0+/-5.5 lb.) and low urinary output were characteristic peri-operative events. Maternal hypoproteinemia and anemia occur in TTTS at mid-pregnancy. This may contribute independently to amniotic fluid production rates in the fetuses, and explain in part the maternal sensitivity to intravenous fluids in multiple pregnancy.
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Affiliation(s)
- J E De Lia
- Department of Obstetrics and Gynecology, University of Illinois, Chicago, USA
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Emery MG, Jubert C, Thummel KE, Kharasch ED. Duration of cytochrome P-450 2E1 (CYP2E1) inhibition and estimation of functional CYP2E1 enzyme half-life after single-dose disulfiram administration in humans. J Pharmacol Exp Ther 1999; 291:213-9. [PMID: 10490907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
Disulfiram (DSF) is a mechanism-based inhibitor of cytochrome P-450 2E1 (CYP2E1), resulting in loss of CYP2E1 protein and activity, which may be useful in preventing CYP2E1-mediated xenobiotic toxicity. The duration of inhibition after a single DSF dose is, however, unknown. The purpose of this investigation was to determine this duration, and CYP2E1 formation and degradation rates, in humans. Oral chlorzoxazone (CLZ) was used as the selective in vivo probe for CYP2E1. Healthy subjects received CLZ to determine baseline CYP2E1 activity (CLZ plasma clearance and 6-hydroxychlorzoxazone fractional metabolic clearance). One week later, DSF (500 mg orally) was administered at bedtime, and CLZ administered the following morning and 3, 6, 8, 10, and 13 days after DSF. A terminal DSF metabolite, 2-thiothiazolidine-4 carboxylic acid, was also measured in each 24-h urine sample. The mean CLZ clearance and 6-hydroxychlorzoxazone fractional metabolic clearance on the first day declined to 10.2 and 5.5% of baseline values, indicating rapid and profound CYP2E1 inhibition. CYP2E1 activity returned to half that of control on day 3, and to baseline values on day 8. Assuming zero-order synthesis and first-order degradation, the in vivo CYP2E1 synthesis rate and degradation half-life was estimated to be 11 +/- 5 nmol/h and 50 +/- 19 h, respectively. Significant amounts of 2-thiothiazolidine-4 carboxylic acid were present only on day 1, suggesting that the return of in vivo CYP2E1 activity was not caused by inhibitor washout, but by enzyme resynthesis. Results regarding CYP2E1 disposition may be useful for modeling the effects of CYP2E1 inducers and inhibitors. For prevention of CYP2E1-mediated bioactivation, depending on protoxicant disposition, a second DSF dose might be necessary to completely prevent toxicity.
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Affiliation(s)
- M G Emery
- Department of Pharmaceutics, Anesthesiology Service, Puget Sound Veterans Affairs Medical Center, Seattle, Washington, USA
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Gunderson-Warner S, Martinez LP, Martinez IP, Carey JC, Kochenour NK, Emery MG. Critical review of articles regarding pregnancy exposures in popular magazines. Teratology 1990; 42:469-72. [PMID: 2278023 DOI: 10.1002/tera.1420420503] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
To determine the scope of teratogen information available to the public through the media, a survey of 15 popular magazines was conducted. All 1985 issues of the selected magazines were reviewed for articles addressing pregnancy exposure concerns, yielding 56 articles from 10 magazines. The remaining 5 publications provided no pertinent articles. Two health professionals, both experienced teratology counselors, independently rated each article for accuracy of content and quality of presentation based on standardized evaluation criteria. The findings were compared and agreement for all criteria in each article was reached by the 2 reviewers. Regarding the quality of the information in the 56 articles, 31 (55.4%) were scored as misleading or inaccurate. On examination of overall presentation, 26 (46.4%) were rated as alarming and 8 (14.3%) presented a false sense of security; 22 (39.3%) provided a balanced presentation. A review of the types of articles rated revealed 19 (33.9%) general overviews of pregnancy issues, 18 (32.1%) news stories, 17 (30.4%) question-and-answer columns, and 2 (3.6%) feature stories. Of the reviewed papers, 7 (12.5%) included a citation from which the primary data could be obtained and only 14 of the articles (25%) suggested that the reader contact her/his healthcare provider regarding the issues. We conclude that the information available in popular magazines regarding exposures in pregnancy is frequently misleading, alarming, and unsupported by the scientific literature.
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Golembeski DJ, Emery MG. Lipid composition of milk from mothers with cystic fibrosis. Pediatrics 1989; 83:631-2. [PMID: 2928008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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Lau RJ, Emery MG, Galinsky RE. Unexpected accumulation of acyclovir in breast milk with estimation of infant exposure. Obstet Gynecol 1987; 69:468-71. [PMID: 3808527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Although acyclovir is prescribed to women of reproductive age, no information currently exists regarding the advisability of its use in lactating women. This report documents the first known case of acyclovir transfer to an infant through breast milk. Maternal plasma, milk, and infant urine were collected following a 200-mg oral dose of acyclovir. The drug concentration in breast milk exceeded the corresponding plasma concentration except at the time of peak plasma concentration. This would not be expected on the basis of simple diffusion, and might be caused by a facilitated or active transport mechanism. Such a mechanism has not been described for any drug in human breast milk. Subtherapeutic amounts of acyclovir were documented in the infant, and we discuss the potential effects on neonatal immune function. The use of acyclovir in lactating women remains controversial until further study can clarify pertinent questions.
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De Lia JE, Emery MG. Digoxin therapy in the fetus. Am J Dis Child 1986; 140:974-5. [PMID: 3752029 DOI: 10.1001/archpedi.1986.02140240020015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Abstract
A pregnancy complicated by twin transfusion syndrome is presented. When signs of cardiac failure (edema, ascites and hydramnios) persisted in the recipient twin, maternal digoxin therapy was instituted at 27 weeks' gestation. The signs of failure resolved, and the twins were delivered electively by cesarean section at 34 weeks. At birth, the syndrome was confirmed by examination of the infants and placenta. Both infants survived. Digoxin therapy is recommended for fetal heart failure from circulatory overload in twin transfusion.
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Abstract
Reports on the efficacy of flurbiprofen for dysmenorrhea conflict. We gave 59 dysmenorrheic patients flurbiprofen (50 mg), aspirin (650 mg), or placebo. Paired drug comparisons showed that patients preferred flurbiprofen and that it was more effective in relief of pain, in allowing patients to pursue normal daily function, and in reducing the need for additional analgesics. Except in patient preference, aspirin was only marginally superior to placebo, There was an increase in minor side effects in the flurbiprofen group, but our results indicate therapeutic utility for flurbiprofen in dysmenorrhea.
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Kochenour NK, Emery MG, Sawchuk RJ. Phenytoin metabolism in pregnancy. Obstet Gynecol 1980; 56:577-82. [PMID: 7432728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Approximately 45% of patients with epilepsy experience an increase in seizure frequency during pregnancy. Despite the availability of effective anticonvulsant medications, there has been no decrease in reported seizure frequency accompanying pregnancy in the past 35 years. The authors prospectively studied concentrations of phenytoin (DPH) and its metabolites in 5 patients throughout pregnancy and during the postpartum period. The concentrations of phenytoin, as well as both unconjugated and conjugated forms of its principal metabolite, 5-(4-hydroxyphenyl)-5-phenylhydantoin (4-OH-DPH), were measured in plasma and urine by a precise high-pressure liquid chromatography method. Four patients experienced a decrease in plasma DPH during gestation, 3 of whom developed seizures at a time of low plasma DPH concentration. Within the therapeutic range, small increments in dosage resulted in large increments in plasma DPH levels, and in the postpartum period high levels of DPH were encountered if the dosage was not reduced. As pregnancy progressed, there was a decrease in the percentage of the daily dosage of DPH excreted as 4-OH-DPH. Based on these observations, the authors conclude that 1) pregnancy is associated with altered DPH absorption or metabolism or both, and 2) periodic measurement of plasma DPH concentration is valuable when managing a pregnant epileptic patient.
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