In recent years the use of the opioid oxycodone has increased markedly and replacing morphine as the first-line choice of opioid in several countries. There are formulations for oral immediate, oral ...extended release and intravenous use. The bioavailability is higher than for morphine and less variable. Oxycodone is primarily metabolized in the liver by the cytochrome P450 (CYP) enzymes with CYP3A as the major metabolic pathway and CYP2D6 as the minor metabolic pathway to noroxycodone, oxymorphone and noroxymorphone. Oxycodone exerts its analgesic effect via the µ-opioid receptor. The metabolism of CYP2D6 substrates varies to a large degree between individuals as a result of allele functionality. Poor metabolizers (PM) have two non-functional alleles, extensive metabolizers (EM) are homozygous with two functional alleles or heterozygous with one functional allele and ultrarapid metabolizers (UM) have more than two functional alleles. There are pronounced interethnic differences in the allele distribution. On the basis of studies performed thus far, oxycodone concentrations in comparison with EM are similar in PM and reduced in UM. The pharmacokinetics in UM are insufficiently investigated. Simultaneous inhibition of both CYP3A and CYP2D6 results in increased oxycodone concentrations and such a combination should be avoided. A similar effect is to be expected with use of a CYP3A inhibitor in CYP2D6 PM. Concomitant use of enzyme inducers such as rifampicin, St John’s wort and carbamazepine should be avoided because of the risk of subtherapeutic concentrations of oxycodone. When the dosage of morphine may result in unpredictable bioavailability, like in patients with severe hepatic cirrhosis, oxycodone might be beneficial because it has higher and less variability in bioavailability between patients than morphine.
Ciprofloxacin, given to a patient successfully treated with methadone for more than 6 years, caused profound sedation, confusion, and respiratory depression. We suggest that this was caused by ...ciprofloxacin inhibition of CYP1A2 and CYP3A4 activity, two of the cytochrome p450 isozymes involved in the metabolism of methadone.
Global Health is a young discipline with equity of health and services as its core value. The discipline has a tradition of close links between practice and research in line with the 'Health for All' ...declaration launched by the World Health Organization (WHO) in 1978. The multitude of existential health crises facing mankind require a research agenda in line with Global Health Research core values and methods, such as transdisciplinary collaboration, long time series of population-based observations and multifaceted interventions. Knowledge gaps cover climate effects on health and mechanisms for global spread and control of antibiotic resistance across species. Such health threats are preferably studied at Health and Demographic Surveillance Sites, a scientific infrastructure for Global Health Research in Africa and Asia, that gains to expand and monitor climate parameters and include sites in the northern hemisphere. Global Health Scientists together with science societies can ensure long-term funding of a global network of population-based health-climate sites. Global Health Scientists and scientific journals should jointly provide data and evidence on global health to governance bodies on regional, national and global levels, in particular to WHO and United Nations in charge of the programme with Sustainable Development Goals.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
•An LC–MS/MS dried blood spot method for common antiepileptic drugs was validated.•96-well format, automatic punching and barcode reading for improved workflow.•The method is accurate in a hematocrit ...range of 0.35–0.50L/L.•Unknown blood volumes between 15 and 50μL can be measured with bias within ±10%.•Stability tests showed that DBS shipping and storage for these drugs were robust.
Monitoring of antiepileptic drugs in children with epilepsy require multiple visits at a clinic for blood collection. Dried blood spot sampling is an alternative way of collection, performed at home by self-collection and can save time and costs for patients and family members. The aim was to develop and validate an LC–MS/MS dried blood spot method for carbamazepine, lamotrigine, levetiracetam and valproic acid with the requirements of using standard equipment and material in a routine laboratory setting.
Whatman-903 filter paper was utilized, and discs were punched into a 96 well plate with an automated puncher and barcode reading. Extraction with methanol/water solution including internal standards on an orbital shaker was followed by a vacuum centrifuge step and reconstitution in mobile phase. Bioanalytical validation was performed according to guidelines from European Medicines Agency and additional dried blood spot specific validation.
Calibration curves of the four included drugs had R2 values ≥0.994. Therapeutic relevant concentrations were well within measuring ranges. Within and −between run precision had %CV:s of 2.9–10.5%. Accuracy (%bias) was between −16.5% (lower limit of quantification) to +7.4%. Blood spots in a volume range of 15–50μL with hematocrit in expected ranges for this patient group were within precision and accuracy limits. To test the method, concentrations from dried blood spot venous and capillary patient samples (n=50) were compared with plasma concentrations. Good correlations for all four drugs with R2 of >0.92 was shown.
In summary, a fast method for dried blood spots based on a 96 well format was developed for four commonly prescribed antiepileptic drugs. This validated method with traceability in sample preparation by bar code reading makes it suitable for the clinical laboratory.
Adherence to antiretroviral treatment (ART) is important to achieve treatment success in human immunodeficiency virus (HIV)-infected patients. Most HIV clinics apply the patient self-report (PSR) ...method. However, the reliability of this method in experienced HIV patients remains questionable.
To validate the PSR method for measuring adherence to ART using lamivudine (3TC) plasma concentrations in experienced HIV patients.
The study was conducted in Dar Es Salaam and involved 220 patients who were receiving ART services at HIV clinics for more than 12 months. Self-reported adherence information to ART was obtained on the day of HIV clinic visit. The patients were asked to mention the number of doses missed within the past 7 days. In addition, blood samples (2 mL) were collected from each patient on the same day. The blood samples were determined for 3TC plasma concentrations. The target 3TC plasma concentration as indicator concentration for adherent patients was determined in 20 patients who took their evening dose of antiretrovirals under supervision. The blood from these patients was drawn 3 hours after drug administration.
Complete drug levels of 3TC and self-reported adherence data was obtained in 200 treatment-experienced HIV patients. Lamivudine plasma concentrations obtained in these patients ranged between 0.02-17.36 μg/mL. The mean time from dose administration to blood drawing was 3.1 ± 1.2 hours with coefficient of variation >39%. The mean 3TC plasma concentration obtained in 20 patients who took their antiretroviral dose under supervision was found to be 0.67 ± 0.46 μg/mL, range 0.25-2.33 μg/mL. As many as 82.5% of experienced HIV patients had PSRs in agreement with their 3TC plasma concentrations.
PSR adherence is still a valid method for ascertaining adherence to ART in treatment-experienced HIV patients.
Purpose
Sertraline, a selective serotonin reuptake inhibitor (SSRI), is one of the most commonly used antidepressant during pregnancy. Plasma sertraline concentrations vary markedly between ...individuals, partly explained by variability in hepatic drug metabolizing cytochrome P450-enzyme activity. Our purpose was to study the variability in the plasma concentrations in pregnant women and the passage to their infants.
Method
Pregnant women with moderate untreated depression were recruited in 2016–2019 in Stockholm Region and randomized to treatment with sertraline or placebo. All received Internet-based cognitive behavior therapy as non-medical treatment. Sertraline plasma concentrations were measured around pregnancy weeks 21 and 30, at delivery, 1-month postpartum, in cord blood and at 48 h of age in the infant. The clinical course of the infants was followed.
Results
Nine mothers and 7 infants were included in the analysis. Median dose-adjusted sertraline concentration in second trimester was 0.15(ng/mL) /(mg/day), in third trimester and at delivery 0.19 and 1-month postpartum 0.25, with a 67% relative difference between second trimester and postpartum. The interindividual variation was 10-fold. Median concentrations in the infants were 33% and 25% of their mothers’, measured in cord blood, and infant plasma, respectively. Only mild and transient adverse effects were seen on the infants.
Conclusion
Placental passage of sertraline to the infant is low. However, the interindividual variation in maternal concentrations during pregnancy is huge, why therapeutic drug monitoring might assist in finding the poor metabolizers at risk for adversity and increase the safety of the treatment.
Trial registration
The trial was registered at
clinicaltrials.gov
July 9, 2014 with TRN: NCT02185547.
There has been an increase in 'risk sharing' schemes for pharmaceuticals between healthcare institutions and pharmaceutical companies in Europe in recent years as an additional approach to provide ...continued comprehensive and equitable healthcare. There is though confusion surrounding the terminology as well as concerns with existing schemes.
A literature review was undertaken to identify existing schemes supplemented with additional internal documents or web-based references known to the authors. This was combined with the extensive knowledge of health authority personnel from 14 different countries and locations involved with these schemes.
A large number of 'risk sharing' schemes with pharmaceuticals are in existence incorporating both financial-based models and performance-based/outcomes-based models. In view of this, a new logical definition is proposed. This is "risk sharing' schemes should be considered as agreements concluded by payers and pharmaceutical companies to diminish the impact on payers' budgets for new and existing schemes brought about by uncertainty and/or the need to work within finite budgets". There are a number of concerns with existing schemes. These include potentially high administration costs, lack of transparency, conflicts of interest, and whether health authorities will end up funding an appreciable proportion of a new drug's development costs. In addition, there is a paucity of published evaluations of existing schemes with pharmaceuticals.
We believe there are only a limited number of situations where 'risk sharing' schemes should be considered as well as factors that should be considered by payers in advance of implementation. This includes their objective, appropriateness, the availability of competent staff to fully evaluate proposed schemes as well as access to IT support. This also includes whether systematic evaluations have been built into proposed schemes.
Celotno besedilo
Dostopno za:
CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Intrauterine exposure to antidepressants may lead to neonatal symptoms from the central nervous system, respiratory system and gastrointestinal system. Finnegan score (Neonatal Abstinence Score, NAS) ...has routinely been used to assess infants exposed to antidepressants in utero.
The purpose was to study neonatal maladaptation syndrome in infants exposed to selective serotonin reuptake inhibitors (SSRI) or serotonin-norepinephrine reuptake inhibitors (SNRI) in utero.
Retrospective cohort study of women using antidepressants during pregnancy and their infants. Patients were identified from the electronic health record system at Karolinska University Hospital Huddinge containing pre-, peri- and postnatal information. Information was collected on maternal and infant health, social factors and pregnancy. NAS sheets were scrutinized.
220 women with reported 3rd trimester exposure to SSRIs or SNRIs and who gave birth between January 2007 and June 2009 were included. Seventy seven women (35%) used citalopram, 76 used (35%) sertraline, 34 (15%) fluoxetine and 33 (15%) other SSRI/SNRI. Twenty-nine infants (13%) were admitted to the neonatal ward, 19 were born prematurely. NAS was analyzed in 205 patients. Severe abstinence was defined as eight points or higher on at least two occasions (on a scale with maximum 40 points), mild abstinence as 4 points or higher on at least two occasions. Seven infants expressed signs of severe abstinence and 46 (22%) had mild abstinence symptoms. Hypoglycemia (plasma glucose <2.6 mmol/L) was found in 42 infants (19%).
Severe abstinence in infants prenatally exposed to antidepressants was found to be rare (3%) in this study population, a slightly lower prevalence than reported in previous studies. Neonatal hypoglycemia in infants prenatally exposed to antidepressant may however be more common than previously described.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To investigate if dried blood spots could be used for therapeutic drug monitoring of the antiepileptic drugs, carbamazepine, lamotrigine and valproic acid in children with epilepsy.
Fingerprick blood ...samples from 46 children at a neuropediatric outpatient clinic was collected on filterpaper at the same time as capillary plasma sampling. A validated dried blood spot liquid chromatography tandem mass spectrometry method for carbamazepine, lamotrigine and valproic acid was compared with the routine plasma laboratory methods. Method agreement was evaluated and plasma concentrations were estimated by different conversion approaches.
Strong correlation was shown between dried blood spot and plasma concentrations for all three drugs, with R2 values>0.89. Regression analysis showed a proportional bias with 35% lower dried blood spot concentrations for valproic acid (n=33) and concentrations were 18% higher for carbamazepine (n=17). A ratio approach was used to make a conversion from dried blood spots to estimated plasma for these two drugs. Dried blood spot concentrations were directly comparable with plasma for lamotrigine (n=20).
This study supports that dried blood spot concentrations can be used as an alternative to plasma in a children population for three commonly used antiepileptic drugs with the possibility to expand by adding other antiepileptic drugs. Clinical decisions can be made based on converted (carbamazepine, valproic acid) or unconverted (lamotrigine) dried blood spot concentrations. Dried blood spot sampling, in the future taken at home, will simplify an effective therapeutic drug monitoring for this group of patients who often have concomitant disorders and also reduce costs for society.
•Clinical TDM decisions of AEDs can be made from DBS or converted DBS concentrations in a children population.•Drugs with a blood/plasma ratio ≠ 1 may need conversion between DBS and plasma.•Use of a theoretical approach is problematic due to variations in RBC/plasma ratio at different concentrations and HCT levels.•Conversion of DBS to plasma concentrations is possible with a simple factor.
Pharmacogenetics contributes to inter-individual variability in pharmacokinetics (PK) of efavirenz (EFV), leading to variations in both efficacy and toxicity. The purpose of this study was to assess ...the effect of genetic factors on EFV pharmacokinetics, treatment outcomes and genotype based EFV dose recommendations for adult HIV-1 infected Ugandans.
In total, 556 steady-state plasma EFV concentrations from 99 HIV infected patients (64 female) treated with EFV/lamivudine/zidovidine were analyzed. Patient genotypes for CYP2B6 (*6 & *11), CYP3A5 (*3,*6 & *7) and ABCB1 c.4046A>G, baseline biochemistries and CD4 and viral load change from baseline were determined. A one-compartment population PK model with first-order absorption (NONMEM) was used to estimate genotype effects on EFV pharmacokinetics. PK simulations were performed based upon population genotype frequencies. Predicted AUCs were compared between the product label and simulations for doses of 300 mg, 450 mg, and 600 mg.
EFV apparent clearance (CL/F) was 2.2 and 1.74 fold higher in CYP2B6*6 (*1/*1) and CYP2B6*6 (*1/*6) compared CYP2B6*6 (*6/*6) carriers, while a 22% increase in F1 was observed for carriers of ABCB1 c.4046A>G variant allele. Higher mean AUC was attained in CYP2B6 *6/*6 genotypes compared to CYP2B6 *1/*1 (p<0.0001). Simulation based AUCs for 600 mg doses were 1.25 and 2.10 times the product label mean AUC for the Ugandan population in general and CYP2B6*6/*6 genotypes respectively. Simulated exposures for EFV daily doses of 300 mg and 450 mg are comparable to the product label. Viral load fell precipitously on treatment, with only six patients having HIV RNA >40 copies/mL after 84 days of treatment. No trend with exposure was noted for these six patients.
Results of this study suggest that daily doses of 450 mg and 300 mg might meet the EFV treatment needs of HIV-1 infected Ugandans in general and individuals homozygous for CYP2B6*6 mutation, respectively.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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