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Objective: Harmonized European NSCLC incidence, treatment approach, and survival based on national tumor registries are unclear., Summary Background Data: Surgery has the potential to cure NSCLC and significantly prolong survival. This large-scale international study aimed to investigate treatment variations in Europe and the USA, as well as the determinants for its utilization., Methods: The retrospective cohort study analyzed data from six European national population-based cancer registries (Belgium, Denmark, Estonia, Germany, the Netherlands, and Slovenia) and the US SEER database from 2010-2015., Results: The study computed cancer incidence, survival, and age-standardized proportions of the use of various therapies. Multivariable logistic regression models were used to assess associations between resection and demographic and clinical parameters. A total of 428,107 records were analyzed. Among all countries, Estonia had the highest surgical resection rate (79.3 %) and the lowest radiation rate (7.3 %) for stage I patients. The Netherlands had the highest rate of radiotherapy across all years of investigation and the lowest surgery rate between 2012 and 2015. The primary treatment for early-stage NSCLC showed significant international variation, with the USA having a decrease in surgical rates from 67.6 % to 59.5 %. Resection was less frequently performed as tumor stage increased, patients aged, other lung cancer besides adenocarcinoma was present, and when the tumor site overlapped multiple lobes., Conclusions: Resection rates have declined in some studied European countries and the USA and resection rates vary substantially among countries. Interpretation of current scientific lung cancer evidence and international guidelines results in wide variations in patient treatment., Competing Interests: Declaration of Competing Interest A.F.T.M. Verhagen reports institutional payments from Johnson & Johnson and Bristol Myers Squibb. Kersti Oselin declares research grants from Pfizer to study the role of artificial intelligence and genomic factors in lung cancer recurrence 2021 and an ongoing research collaboration with Optellum to develop an artificial intelligence tool to assess lung cancer prognosis. She reports travel support from MSD, Roche and Astra Zeneca. H. Winter reports consultancy fees, travel support and data safety monitoring honoraria from Astra Zeneca, Roche and Intuitive Surgical. All other authors declare no competing interests., (Copyright © 2024. Published by Elsevier Ltd.)

Arcagen (NCT02834884) is a European prospective study aiming at defining the molecular landscape of rare cancers for treatment guidance. We present data from the cohort of rare thoracic tumors. Patients with advanced pleural mesothelioma (PM) or thymic epithelial tumors (TET) underwent genomic profiling with large targeted assay [>300 genes, tumor mutational burden (TMB), microsatellite instability (MSI) status] on formalin-fixed paraffin-embedded (FFPE) or plasma samples. EORTC molecular tumor board (MTB) advised for biomarker-guided treatments. 102 patients recruited from 8 countries between July 2019 and May 2022 were evaluable: 56 with PM, 46 with TET (23 thymomas, 23 thymic carcinomas). Molecular profiling was performed on 70 FFPE samples (42 PM, 28 TET), and 32 cases on ctDNA (14 PM, 18 TET), within a median turnaround time of 8 days from sample reception. We detected relevant molecular alterations in 66 out of 102 patients (65%; 79% PM, 48% TET), 51 of 70 FFPE samples (73%; 90% PM, 46% TET), and 15 of 32 plasma samples (47%; 43% PM, 50% TET). The most frequently altered genes were CDKN2A/B, BAP1, MTAP in PM and TP53, CDKN2A/B, SETD2 in TET. The TMB was low (mean 3.2 Muts/MB), 2 PM had MSI-high status. MTB advised molecular-guided treatment options in 32 situations, for 17 PM and 15 TET patients (75% clinical trial option, 22% off-label drug or compassionate use, 3% early access program). Molecular testing and MTB discussion were feasible for patients with rare thoracic cancers and allowed the broadening of treatment options for 30% of the cases., (© 2024. The Author(s).)

Purpose: Spironolactone is a potassium sparing diuretic used for decades. Until now, pharmacokinetic (PK) studies of spironolactone have not been conducted in infants and therefore pediatric dosing is based on expert opinion. We aimed to describe the PK profiles of spironolactone and its main metabolites (7alpha-thiomethylspironolactone (TMS) and canrenone (CAN)) in infants up to two years of age., Methods: The PK of spironolactone and its main metabolites were evaluated following an oral administration of spironolactone (1 mg/kg/dose) to pediatric patients with chronic heart failure, ascites, and/or oedema. The plasma concentration of spironolactone and metabolites (TMS and CAN) was determined using an ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Based on rich sampling PK data, the estimation of population PK parameters was performed using nonlinear mixed-effects modelling software Monolix 2018R2., Results: A total of 150 spironolactone, 158 TMS, and 158 CAN concentrations from 23 patients (ages: 3 days-21 months; median weight 4.3 kg (2.2-12.6)) were available for PK analysis. A one-compartment model for spironolactone, TMS, and CAN best fitted the data. The median (range) of individual estimated apparent clearance values were 47.7 (11.9-138.1) L/h for spironolactone, 9.7 (1.5-66.9) L/h for TMS, and 1.0 (0.2-5.9) L/h for CAN. The disposition of spironolactone and metabolites was mainly affected by size of the patient: body weight explained 22% of inter-individual variability of spironolactone clearance. None of the undesirable effects of spironolactone was documented during the study period., Conclusion: The pharmacokinetics of spironolactone and its metabolites was highly variable between patients below 2 years of age. Body weight explained a significant part of this variability; this highlights the need to take it into account for dosing prescription in this population. (Clinical trial Registration Number 2013-001189-40)., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Lung cancer remains the leading cause of cancer-related deaths in Europe, with non-small cell lung cancer (NSCLC) accounting for approximately 85% of cases. NSCLC is a heterogeneous disease encompassing various oncogenic alterations. Among them, EGFR exon 20 insertion mutations, constituting 0.3-2.2% of NSCLC cases, rank as the third most common EGFR alteration after exon 19 deletions and the L858R point mutation in exon 21, also known as "typical" EGFR alterations. Recent advancements in understanding the molecular pathogenesis of NSCLC have led to significant breakthroughs in targeted therapies, revolutionizing treatment options for patients with specific genetic alterations.This article presents the outcomes of a Virtual Meeting conducted on the online platform (provided Within3©) from September 19 to October 30, 2022. The meeting focused on addressing the challenges in the diagnosis and treatment of NSCLC patients with EGFR exon 20 insertion mutations. The participants consisted of healthcare professionals from ten Central and Eastern European countries who shared their experiences and opinions on various aspects, including epidemiology, treatment options, and diagnostic approaches employed in their respective healthcare institutions. The discussions were facilitated through open-ended and multiple-choice questions.The primary objective of this article is to provide an overview of the identified challenges associated with the diagnosis and treatment of this heterogeneous disease, based on the assessments of the meeting participants. Among the major emerging challenges discussed, the reimbursement issues concerning next-generation sequencing (NGS), a recommended method in NSCLC molecular diagnosis, and the availability of approved targeted treatments to enhance patient outcomes were of paramount importance. Furthermore, fostering community awareness of lung cancer and promoting harmonized lung cancer care were identified as areas deserving greater attention. Notably, the rapidly evolving treatment landscape, particularly with NGS for NSCLC patients with genomic alterations like EGFR, ALK, RET, MET, NTRK, and ROS1, necessitates prioritizing the development of new drugs, even for the relatively smaller subgroup with exon 20 insertion mutations., (© 2023. The Author(s).)

Introduction: 33-70% of lung cancer (LC) patients develop recurrence after radical treatment. Previous studies have shown the importance of clinical-pathological characteristics for the risk of recurrence. The role of molecular mechanisms remains unclear. The aim was analyzing genomic features in LC patients with local (LR) versus distant recurrence (DR) to predict the risk and type of recurrence., Materials and Methods: Patients previously curatively treated with LC recurrences from 2015 to 2017 were retrospectively enrolled. Histological specimens collected at the time of LC diagnosis were sent for whole exome sequencing (WES). Genomic data was analyzed for single nucleotide polymorphisms (SNPs) and insertion-deletion mutations (INDELs)., Results: 191 patients were included. 33% of patients had LR and 67% DR, with median recurrence-free survival (RFS) 15.4 versus 11.2 months (p = 0.20) and overall survival (OS) after recurrence 12.9 versus 8.5 months (p = 0.007), respectively. Of various laboratory parameters studied, lymphocytes were significantly decreased at recurrence (p < 0.0001) in the DR group. In genetic analysis, significantly enriched INDEL mutations were found in 38 and 98 genes and SNP mutations in 63 and 179 genes in DR and LR groups, respectively. DMXL2 and ABCC9 gene mutations caused by INDELs appeared exclusively in the DR group. Enrichment analysis detected genes, like KNTC1, CLASP1, CLASP2 and CENPE, responsible of microtubule disturbance in the DR group. Furthermore, genes related to cytosolic Ca2+ such as STIM1, ITPR3 and RYR3, were significantly enriched in DR group whereas in LR group enrichment of pathways related to endoplasmic/sarcoplasmic reticulum Ca2+ was observed., Conclusion: Our findings indicate distinct genomic signatures in the LR and DR cohorts, with microtubule disturbance and calcium regulation playing a crucial role in invasiveness in DR of LC. Understanding molecular mechanisms of LC recurrence may lead to the discovery of novel drug targets that could potentially stop spread of cancer cells., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Pembrolizumab is a standard-of-care for advanced non-small-cell lung cancer (NSCLC). We assessed pembrolizumab as adjuvant therapy for completely resected stage IB-IIIA NSCLC., Methods: In this randomised, triple-blind, phase 3 trial (PEARLS/KEYNOTE-091), patients were recruited from 196 medical centres in 29 countries. Eligible patients were aged 18 years or older, with completely resected, pathologically confirmed stage IB (tumours of ≥4 cm in diameter), II, or IIIA NSCLC per the American Joint Committee on Cancer staging system (7th edition) of any histology or PD-L1 expression level, and an Eastern Cooperative Oncology Group performance status of 0 or 1; adjuvant chemotherapy was to be considered for stage IB disease and was strongly recommended for stage II and IIIA disease, according to national and local guidelines. Using a central interactive voice-response system, eligible participants were randomly assigned (1:1), using a minimisation technique and stratified by disease stage, previous adjuvant chemotherapy, PD-L1 expression, and geographical region, to pembrolizumab 200 mg or placebo, both administered intravenously every 3 weeks for up to 18 cycles. Participants, investigators, and analysts were masked to treatment assignment. Dual primary endpoints were disease-free survival in the overall population and in the population with PD-L1 tumour proportion score (TPS) of 50% or greater. Efficacy was assessed in the intention-to-treat (ITT) population (ie, all participants randomly assigned to a treatment group). Safety was assessed in all participants randomly assigned to treatment who received at least one dose of study treatment. Here we report results of the second interim analysis, prespecified to occur when approximately 118 disease-free survival events had occurred in the PD-L1 TPS of 50% or greater population. This study is registered with ClinicalTrials.gov, NCT02504372, and is active but not recruiting., Findings: Between Jan 20, 2016, and May 6, 2020, 1177 (60%) of 1955 screened participants were randomly assigned to pembrolizumab (n=590, including n=168 with PD-L1 TPS of ≥50%) or placebo (n=587; including n=165 with PD-L1 TPS of ≥50%) and included in the ITT population. Median follow-up as of data cutoff (Sept 20, 2021) for this interim analysis was 35·6 months (IQR 27·1-45·5). In the overall population, median disease-free survival was 53·6 months (95% CI 39·2 to not reached) in the pembrolizumab group versus 42·0 months (31·3 to not reached) in the placebo group (HR 0·76 [95% CI 0·63-0·91], p=0·0014). In the PD-L1 TPS of 50% or greater population, median disease-free survival was not reached in either the pembrolizumab group (95% CI 44·3 to not reached) or the placebo group (95% CI 35·8 to not reached; HR 0·82 [95% CI 0·57-1·18]; p=0·14). Grade 3 or worse adverse events occurred in 198 (34%) of 580 participants who received pembrolizumab and 150 (26%) of 581 participants who received placebo. Grade 3 or worse events that occurred in at least ten participants in either treatment group were hypertension (35 [6%]) and pneumonia (12 [2%]) with pembrolizumab and hypertension (32 [6%]) with placebo. Serious adverse events occurred in 142 (24%) participants in the pembrolizumab group and 90 (15%) in the placebo group; serious adverse events that occurred in more than 1% of participants were pneumonia (13 [2%]), pneumonitis (12 [2%]), and diarrhoea (seven [1%]) with pembrolizumab and pneumonia (nine [2%]) with placebo. Treatment-related adverse events led to death in four (1%) participants treated with pembrolizumab (one due to both cardiogenic shock and myocarditis, one due to both septic shock and myocarditis, one due to pneumonia, and one due to sudden death) and in no participants treated with placebo., Interpretation: Pembrolizumab significantly improved disease-free survival compared with placebo and was not associated with new safety signals in completely resected, PD-L1-unselected, stage IB-IIIA NSCLC. Pembrolizumab is potentially a new treatment option for stage IB-IIIA NSCLC after complete resection and, when recommended, adjuvant chemotherapy, regardless of PD-L1 expression., Funding: Merck Sharp & Dohme, a subsidiary of Merck & Co., Competing Interests: Declaration of interests MO, LP-A, SM, UD, KO, LH, EE, DI, AM-M, MF, MT, J-SL, KN, MM, NJ, RS, BB, and SP report funding to their institutions from Merck Sharp & Dohme LLC, a subsidiary of Merck & Co (Rahway, NJ, USA; MSD) to support conduct of this study. All authors received medical writing support for the preparation of this manuscript from MSD. MO additionally reports consulting fees for serving on advisory boards for MSD, Merck, Pierre Fabre, Amgen, Puma, Iteos, and PharmaMar; honoraria from Roche and Lilly in China; travel support from MSD; payment for serving as a member of an independent data monitoring committee for PharmaMar; and payment from ALPI (Sweden) for an academic review. LP-A additionally reports institutional grants or contracts from MSD, AstraZeneca, Pfizer, and Bristol Myers Squibb (BMS); consulting fees from Lilly, MSD, Roche, PharmaMar, Merck, AstraZeneca, Novartis, Servier, Amgen, Pfizer, Sanofi, Bayer, BMS, Mirati, GSK, Janssen, and Takeda; honoraria from AstraZeneca, Janssen, Merck, and Mirati; participation on a data safety monitoring board for Altum Sequencing and Genomica; and serving as a principal investigator on trials for Alkermes, Amgen, AstraZeneca, BMS, Daiichi Sankyo, IO Biotech, Janssen-Cilag, Lilly, MSD, Novartis, Pfizer, PharmaMar, Roche, Sanofi, Takeda, and Tesaro. UD additionally reports consulting fees from Roche. KO additionally reports institutional grants or contracts from Pfizer and Takeda; consulting fees from Amgen, Takeda, MSD, Janssen, Roche, and AstraZeneca; and travel support from MSD. DI additionally reports consulting fees from MSD, Roche, AstraZeneca, Amgen, Pfizer, Sanofi, Bayer, BMS, GSK, Janssen, and Takeda; honoraria from MSD, Roche, AstraZeneca, Amgen, Pfizer, Sanofi, Bayer, BMS, and Takeda; and travel support from AstraZeneca. AM-M additionally reports consulting fees for advisory board membership from AstraZeneca/MedImmune, BMS, F Hoffmann-La Roche AG, MSD, and Pfizer; honoraria from AstraZeneca/MedImmune, BMS, F Hoffmann-La Roche AG, MSD, and Pfizer; serving as a steering committee member for AstraZeneca/MedImmune; and travel support from AstraZeneca/MedImmune, BMS, F Hoffmann-La Roche AG, MSD, Pfizer, and Lilly. MF additionally reports honoraria from Roche and Sanofi; travel support from AstraZeneca; and serving as an advisory board member for MSD, Roche, and AstraZeneca. MT additionally reports institutional grants or contracts from Boehringer-Ingelheim Japan, MSD, AstraZeneca KK, Ono Pharmaceutical, and Novartis; consulting fees from AstraZeneca KK, Chugai Pharmaceutical, and MSD KK; honoraria from Johnson & Johnson Japan, AstraZeneca KK, Eli Lilly Japan, Chugai Pharmaceutical, Taiho Pharma, Medtronic Japan, Ono Pharmaceutical, MSD KK, BMS KK, Daiichi Sankyo KK, and Teijin Pharma; serving as a data safety monitoring committee member for Chugai Pharmaceutical; and serving as an advisory board member for AstraZeneca KK, MSD, Novartis, and Eli Lilly. KN additionally reports institutional grants or contracts from AstraZeneca KK, MSD KK, Ono Pharmaceutical, Nippon Boehringer Ingelheim, Novartis Pharma KK, Pfizer Japan, BMS, Eli Lilly Japan KK, Chugai Pharmaceutical, Daiichi Sankyo, Merck Biopharma, Parexel International, PRA Health Sciences, EPS Corporation, Kissei Pharmaceutical, Taiho Pharmaceutical, PPD-SNBL KK, SymBio Pharmaceutical, IQVIA Services Japan KK, Syneos Health Clinical KK, Nippon Kayaku, EP-CRSU, Mebix, Janssen Pharmaceutical KK, AbbVie, Bayer Yakuhin, Eiasi, Mochida Pharmaceutical, Covance Japan, Japan Clinical Research Operations, Takeda Pharmaceutical, GSK KK, Sanofi KK, Sysmex Corporation, Medical Research Support, Otsuka Pharmaceutical, SRL, Pfizer R&D Japan GK, and Amgen; consulting fees from Eli Lilly Japan KK, Kyorin Pharmaceutical, Ono Pharmaceutical, and Pfizer Japan; honoraria from Ono Pharmaceutical, Amgen, Nippon Kayaku, AstraZeneca KK, Chugai Pharmaceutical, Eli Lilly Japan KK, MSD KK, Pfizer Japan, Nippon Boehringer Ingelheim, Taiho Pharmaceutical, Bayer Yakuhin, CMIC ShiftZero KK, Life Technologies Japan, Neo Communication, Roche Diagnostics KK, AbbVie, Merck Biopharma, Kyowa Kirin, Takeda Pharmaceutical, 3H Clinical Trial, CareNet, Medical Review, Yodosha, Nikkei Business Publications, Japan Clinical Research Operations, CMIC, Novartis Pharma KK, Taiyo Pharma, Kyorin Pharmaceutical, BMS KK; and patents with Daiichi Sankyo. RS additionally reports institutional grants or contracts from AstraZeneca, BMS, Daiichi Sankyo, Celgene, Ipsen, Janssen, Mirati, MSD, Novartis, Pfizer, Pierre Fabre, and Roche; consulting fees from AstraZeneca, BMS, Boehringer Ingelheim, GSK, Janssen, MSD, Pfizer, Roche, Sandoz, Seagen, and Takeda; honoraria from Amgen, AstraZeneca, Blueprint Medicines, BMS, Boehringer Ingelheim, GSK, MSD, Novartis, and Roche; data safety monitoring or advisory board participation with Roche and Takeda; and a leadership role with the European Thoracic Oncology Platform International Breast Cancer Study Group (ETOP IBCSG) Partners Foundation. BB additionally reports institutional grants or contracts from 4D Pharma, AbbVie, Amgen, Aptitude Health, AstraZeneca, BeiGene, Blueprint Medicines, Boehringer Ingelheim, Celgene, Cergentis, Chugai Pharmaceutical, Cristal Therapeutics, Daiichi Sankyo, Eli Lilly, Eisai, Genzyme Corporation, GSK, Inivata, Ipsen, Janssen, Onxeo, OSE Immunotherapeutics, Pfizer, Roche-Genentech, Sanofi, Takeda, Tolero Pharmaceuticals, and Turning Point Therapeutics. SP additionally reports institutional grants or contracts from Amgen, AstraZeneca, BeiGene, BMS, GSK, MSD, and Roche/Genentech; consulting fees paid to their institution from AbbVie, AiCME, Amgen, Arcus, AstraZeneca, Bayer, BeiGene, Biocartis, BioInvent, Blueprint Medicines, Boehringer Ingelheim, BMS, Clovis, Daiichi Sankyo, Debiopharm, ecancer, Eli Lilly, Elsevier, F-Star, Fishawack, Foundation Medicine, Genzyme, Gilead, GSK, Illumina, Imedex, IQVIA, Incyte, iTeos, Janssen, Medscape, MSD, Merck Serono, Merrimack, Novartis, Novocure, Oncology Education, PharmaMar, PeerView, PER, Phosplatin Therapeutics, Pfizer, Prime, Regeneron, RMEI, Roche/Genentech, RTP, Sanofi, Seagen, Takeda, and Vaccibody; honoraria paid to their institution from AiCME, AstraZeneca, Boehringer Ingelheim, BMS, ecancer, Eli Lilly, Foundation Medicine, Illumina, Imedex, Medscape, MSD, Mirati, Novartis, PeerView, PER, Pfizer, Prime, Roche/Genentech, RTP, Sanofi, and Takeda; travel support from AstraZeneca, BMS, Daiichi Sankyo, Eli Lilly, MSD, Novartis, Pfizer, Roche/Genentech, and Takeda; and participation on a data safety monitoring or advisory board, with all fees paid to their institution, from AbbVie, Amgen, Arcus, AstraZeneca, Bayer, BeiGene, Biocartis, BioInvent, Blueprint Medicines, Boehringer Ingelheim, BMS, Clovis, Daiichi Sankyo, Debiopharm, Eli Lilly, F-Star, Foundation Medicine, Genzyme, Gilead, GSK, Illumina, Incyte, iTeos, Janssen, MSD, Merck Serono, Merrimack, Novartis, Novocure, PharmaMar, Phosplatin Therapeutics, Pfizer, Regeneron, Roche/Genentech, Sanofi, Seagen, Takeda, and Vaccibody. JY, AS, and SMK report salary for full-time employment from MSD; AS and SMK also own stock in Merck & Co, Rahway, NJ, USA., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background and Aims: Ampicillin is 1 of the most commonly used antibiotics for treatment of early onset sepsis, but its pharmacokinetics (PK) is poorly characterized. We aimed to define the dose of ampicillin for late preterm and term neonates by evaluating its PK in serum, cerebrospinal (CSF), and epithelial lining fluid., Methods: A prospective study included neonates receiving ampicillin for suspected or proven early onset sepsis and pneumonia. PK samples were collected at steady state, at predose and 5 minutes, 1 hour, 3 hours, 8 hours, and 12 hours after ampicillin 3-minute infusion. Ampicillin concentrations were measured by ultra-high-performance liquid chromatography. Noncompartmental anaysis (NCA) and population pharmacokinetic (pop-PK) modeling were performed and probability of therapeutic target attainment was simulated., Results: In 14 neonates (GA of 32-42 wks; mean BW 2873 g), PK parameters (mean ± SD) in NCA were the following: half-life 7.21 ± 7.97 hours; volume of distribution (Vd) 1.07 ± 0.51 L; clearance (CL) 0.20 ± 0.13 L/h; 24-hour area under the concentration-time curve 348.92 ± 114.86 mg*h/L. In pop-PK analysis, a 2-compartmental model described the data most adequately with the final parameter estimates of CL 15.15 (CV 40.47%) L/h/70kg; central Vd 24.87 (CV 37.91%) L/70kg; intercompartmental CL 0.39 (CV 868.56) L/h and peripheral Vd 1.039 (CV 69.32%) L. Peutic target attainment simulations demonstrated that a dosage of 50 mg/kg q 12 hours attained 100% fT > MIC 0.25 mg/L, group B streptococcal breakpoint., Conclusions: We recommend ampicillin dosage 50 mg/kg q 12 hours for neonates with gestational age ≥32 weeks during the first week of life., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Background: We aimed to study the mortality and intensity of health care in patients with advanced lung cancer who received systemic anti-cancer treatment (SACT) compared with patients who were not eligible for SACT (no-SACT)., Methods: A retrospective cohort of patients with lung cancer, who were treated at the North Estonia Medical Centre from 2015 to 2017, was linked to population-based health care data from the Estonian Health Insurance Fund. We calculated 14- and 30-day mortality after SACT and used a composite measure of intensity of care, comprised from the following: emergency department visit, admission to hospital, admission to intensive care unit, receipt of radiotherapy or systemic treatment., Results: The median overall survival (OS) of patients who received at least one cycle of SACT (n = 489) was 9.1 months and in patients with no-SACT (n = 289) 1.3 months (hazard ratio [HR] = 4.23, 95% CI = 3.60-5.00). During the final 30 days of life, intensive EOL care was received by 69.9% of the SACT patients and 43.7% of the no-SACT patients. Intensive EOL care in the last 30 days of life is more probable among patients in the SACT group (odds ratio [OR] = 3.58, 95% CI = 2.54-5.04, p <  0.001), especially in those with a stage IV disease (OR = 1.89, 95% CI = 1.31-2.71, p = 0.001). In the SACT group 6.7 and 14.7% of patients died within 14 days and 30 days after the last cycle, respectively., Conclusions: Significant proportion of patients with advanced lung cancer continue to receive intensive care near death. Our results reflect current patterns of EOL care for patients with lung cancer in Estonia. Availability of palliative care and hospice services must be increased to improve resource use and patient-oriented care.

Our objective was to examine the trends and variation in opioid prescribing in Estonia from 2011 to 2017. This retrospective cross-sectional study is based on a nationwide prescription medicines database. We stratified the analysis by treatment indication (cancer vs noncancer pain). Between 2011 and 2017, annual opioid prescribing rates increased by 67% (from 82.9 to 138.6 prescriptions per 1000 population). The annual number of prescriptions per patient did not change substantially (from 2.94 in 2011 to 2.87 in 2017), and was higher among cancer patients (5.07 vs 2.67 annual prescriptions per cancer and noncancer patients, respectively, in 2017). The use of the most potent opioids (morphine, fentanyl) was higher in noncancer than in cancer patients. The use of prescription opioids is low, and raises concern about the potential undertreatment of cancer pain, in parallel with misuse of opioids for either noncancer pain or diversion., (© 2020 The Authors. Pharmacology Research & Perspectives published by John Wiley & Sons Ltd, British Pharmacological Society and American Society for Pharmacology and Experimental Therapeutics.)

Background: Lung cancer (LC) remains the most frequent cause of cancer death worldwide. We aimed to examine long-term trends in LC survival in Estonia by age, gender, histologic type and stage, with specific focus on surgical treatment. Material and methods: Data on all incident cases of LC diagnosed from 1996 to 2016 were obtained from the Estonian Cancer Registry. Logistic regression was used to examine receipt of surgical treatment in localized LC. Relative survival ratios (RSR) were calculated, and excess hazard ratios (EHR) of death were estimated by stage with gender, age, histology and period of diagnosis as independent variables. Results: Among the total of 16,423 cases, squamous cell carcinoma remained the most common histologic type. The odds of receiving surgical treatment in localized LC increased significantly over time and were associated with age, gender and histologic type. Overall, the age-standardized 5-year RSR improved significantly from 10% in 1996-2002 to 16% in 2010-2016 (from 8% to 15% in men and from 15% to 20% in women). Larger survival gain was seen in younger patients, for non-small cell LC subtypes, and for surgically treated patients. For localized disease, the 5-year RSR increased by more than 20 percentage units, reaching 50% in men and 69% in women. For all stages, the adjusted EHR of death was significantly associated with age, histologic type and period of diagnosis. Conclusions: We observed a substantial improvement of relative survival, with considerable variations across patient groups. After adjustment for age, gender and histology, a significant survival increase over time was seen for all stages. The considerable survival gain observed for localized LC can largely be attributed to rapidly growing proportion of surgically treated patients. Further investigation of LC management practices, particularly the use of non-surgical treatment options is warranted.

Background: Thymic epithelial tumors are rare thoracic tumors for which pathological diagnosis is challenging due to the definition of multiple subtypes, tumor heterogeneity, and variations in interobserver reproducibility. In this study, we aimed at analyzing the quality of pathological reporting in line with the consistency between initial diagnosis and final diagnosis after expert review through a collaboration between the largest thoracic oncology center in Estonia, and one expert center in France., Methods: Hospital electronic database and pathology databases from the Tallinn North Estonia Medical Centre were searched for thymic and mediastinal tumors from 2010 to 2017. Pathology specimens were referred to the Pathology Department of the Lyon University hospital. Overall, 55 tissue specimens from 49 patients were included., Results: From pathology reports, tumor size, diagnosis, and invasion had been mentioned in ≥80% of cases, while resection status and staging were assessed in only 48% and 17% of cases, respectively. The initial diagnosis was consistent with that of the review in 60% of cases. Diagnostic concordance for thymoma subtypes was low (Cohen's kappa 0.34, 95% CI: 0.16-0.52). Overall, a major change in the management of 8 (16%) patients had to be made after pathological review: 3 patients had a normal thymus according to the reference centre, while thymoma B1 or B2 had been diagnosed locally; 5 additional patients had a final diagnosis of non-thymic tumor., Conclusions: Implementing structured pathology reports may help to decrease discrepancies in the diagnosis of thymic epithelial tumors. The development of expert networks is an opportunity to improve diagnosis and patient care, particularly in regard to rare cancers., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Group B streptococci are common causative agents of early-onset neonatal sepsis (EOS). Pharmacokinetic (PK) data for penicillin G have been described for extremely preterm neonates but have been poorly described for late-preterm and term neonates. Thus, evidence-based dosing recommendations are lacking. We describe the PK of penicillin G in neonates with a gestational age (GA) of ≥32 weeks and a postnatal age of <72 h. Penicillin G was administered intravenously at a dose of 25,000 or 50,000 IU/kg of body weight every 12 h (q12h). At steady state, PK blood samples were collected prior to and at 5 min, 1 h, 3 h, 8 h, and 12 h after injection. Noncompartmental PK analysis was performed with WinNonlin software. With those data in combination with data from neonates with a GA of ≤28 weeks, we developed a population PK model using NONMEM software and performed probability of target attainment (PTA) simulations. In total, 16 neonates with a GA of ≥32 weeks were included in noncompartmental analysis. The median volume of distribution ( V ) was 0.50 liters/kg (interquartile range, 0.42 to 0.57 liters/kg), the median clearance (CL) was 0.21 liters/h (interquartile range, 0.16 to 0.29 liters/kg), and the median half-life was 3.6 h (interquartile range, 3.2 to 4.3 h). In the population PK analysis that included 35 neonates, a two-compartment model best described the data. The final parameter estimates were 10.3 liters/70 kg and 29.8 liters/70 kg for V of the central and peripheral compartments, respectively, and 13.2 liters/h/70 kg for CL. Considering the fraction of unbound penicillin G to be 40%, the PTA of an unbound drug concentration that exceeds the MIC for 40% of the dosing interval was >90% for MICs of ≤2 mg/liter with doses of 25,000 IU/kg q12h. In neonates, regardless of GA, the PK parameters of penicillin G were similar. The dose of 25,000 IU/kg q12h is suggested for treatment of group B streptococcal EOS diagnosed within the first 72 h of life. (This study was registered with the EU Clinical Trials Register under EudraCT number 2012-002836-97.)., (Copyright © 2018 American Society for Microbiology.)

Background: Despite differences in types of infection and causative organisms, pharmacokinetic-pharmacodynamic (PKPD) targets of vancomycin therapy derived from adult studies are suggested for neonates. We aimed to identify doses needed for the attainment of AUC/MIC > 400 and AUC/MIC > 300 in neonates with sepsis and correlate these targets with recommended doses and treatment outcome., Methods: Neonates who had Vancomycin therapeutic drug monitoring (TDM) performed between January 1, 2010 and December 31, 2012 were studied. Clinical characteristics, episodes of Gram-positive sepsis with outcomes and all neonatal blood culture isolates in hospital were collected from medical records. To estimate probability of target attainment of AUC/MIC >400 and AUC/MIC >300 a 1000-subject Monte Carlo simulation was performed by calculating AUC using Anderson's (Anderson et al. 2006) and TDM trough concentrations (C trough ) based population PK models., Results: Final dataset included 76 patients; 57 with confirmed Gram-positive sepsis. TDM was taken after the 1 st to 44 th dose. 84.1% of C trough were within the range 5-15 mg/L. Currently recommended doses achieved probability of the targets (PTA) of AUC/MIC >400 and AUC/MIC >300 in less than 25% and 40% of cases, respectively. Doses required for 80% PTA of AUC/MIC > 400 for MIC ≥2 mg/L resulted in C trough values ≥14 mg/L. Mean AUC/MIC values were similar in treatment failure and success groups., Conclusion: With currently recommended vancomycin dosing the therapeutic target of AUC/MIC > 400 is achieved only by 25% of neonates. Appropriate PKPD targets and respective dosing regimens need to be defined in prospective clinical studies in this population.

Background: The purpose of the study was to evaluate the pharmacokinetics (PK) and pharmacodynamics (PD) of piperacillin and tazobactam during high-volume haemodiafiltration (HVHDF)., Methods: A single dose of piperacillin/tazobactam (4/0.5 g) was administered as 30 minute infusion during HVHDF to 10 patients with acute kidney injury due to septic shock. Arterial blood samples were collected before and at 30 or 60 min intervals over 8 h (12 samples) after study drug administration. Concentrations of piperacillin and tazobactam were determined by HPLC-MS/MS. R software was used for population PK analysis and Monte Carlo Simulation of probability of PK/PD target attainment (PTA) in 1000 subjects., Results: A total of 101 samples were collected during HVHDF. The median (IQR) estimated glomerular filtration rate of the patients was 16 (11.25-27.5) ml/min/1.73 m(2) and HVHDF effluent rate was 208 (146.3-298.3) ml/kg/h. A final two-compartment population PK model predicted mean (%SE) total piperacillin clearance on HVHDF was 6.9 (6.4) l/h, volume of distribution of central compartment 9.0 (10.1) l and of peripheral compartment 11.2 (12.2) l. The PTA of 50% fT>MIC for piperacillin 4 g/tazobactam 0.5 g dosed every 8 h as 0.5-h and 4-h infusion was 84.3% and 100% for MIC of 16 mg/l respectively. Aiming 100% fT>MIC of 16 mg/l, the PTA values were 88.6% and 61.0%, for piperacillin 4 g/tazobactam 0.5 g 4-h infusion every 6 and 8 h respectively., Conclusions: For bactericidal PK/PD target attainment piperacillin/tazobactam doses of 4/0.5 g every 8 h appear appropriate in septic shock patients with minimal residual renal function during HVHDF., (© 2015 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Pharmacokinetics (PK) of doripenem was determined during high volume hemodiafiltration (HVHDF) in patients with septic shock. A single 500 mg dose of doripenem was administered as a 1 hour infusion during HVHDF to 9 patients. Arterial blood samples were collected before and at 30 or 60 minute intervals over 8 hours (12 samples) after study drug administration. Doripenem concentrations were determined by ultrahigh performance liquid chromatography-tandem mass spectrometry. Population PK analysis and Monte Carlo simulation of 1,000 subjects were performed. The median convective volume of HVHDF was 10.3 L/h and urine output during the sampling period was 70 mL. The population mean total doripenem clearance on HVHDF was 6.82 L/h, volume of distribution of central compartment 10.8 L, and of peripheral compartment 12.1 L. Doses of 500 mg every 8 hours resulted in 88.5% probability of attaining the target of 50% time over MIC for bacteria with MIC = 2 µg/mL at 48 hours, when doubling of MIC during that time was assumed. Significant elimination of doripenem occurs during HVHDF. Doses of 500 mg every 8 hours are necessary for treatment of infections caused by susceptible bacteria during extended HVHDF., (© 2014, The American College of Clinical Pharmacology.)

Prolonged infusion of meropenem has been suggested in studies with population pharmacokinetic modeling but has not been tested in neonates. We compared the steady-state pharmacokinetics (PK) of meropenem given as a short (30-min) or prolonged (4-h) infusion to very-low-birth-weight (gestational age, <32 weeks; birth weight, <1,200 g) neonates to define the appropriate dosing regimen for a phase 3 efficacy study. Short (n = 9) or prolonged (n = 10) infusions of meropenem were given at a dose of 20 mg/kg every 12 h. Immediately before and 0.5, 1.5, 4, 8, and 12 h after the 4th to 7th doses of meropenem, blood samples were collected. Meropenem concentrations were measured by ultrahigh-performance liquid chromatography. PK analysis was performed with WinNonlin software, and modeling was performed with NONMEM software. A short infusion resulted in a higher mean drug concentration in serum (C(max)) than a prolonged infusion (89 versus 54 mg/liter). In all but two patients in the prolonged-infusion group, the free serum drug concentration was above the MIC (2 mg/liter) 100% of the time. Meropenem clearance (CL) was not influenced by postnatal or postmenstrual age. In population PK analysis, a one-compartment model provided the best fit and the steady-state distribution volume (V(ss)) was scaled with body weight and CL with a published renal maturation function. The covariates serum creatinine and postnatal and gestational ages did not improve the model fit. The final parameter estimates were a V(ss) of 0.301 liter/kg and a CL of 0.061 liter/h/kg. Meropenem infusions of 30 min are acceptable as they balance a reasonably high C(max) with convenience of dosing. In very-low-birth-weight neonates, no dosing adjustment is needed over the first month of life.

Background: The amount of blood that can be safely drawn from a preterm neonate for scientific purposes is poorly established., Objectives: To provide scientific evidence on the amount of blood that can be drawn from very low birth weight (VLBW) neonates for study purposes., Methods: We performed a post-hoc analysis of a pharmacokinetic (PK) study of penicillin-G, enrolling 18 neonates with a birth weight of <1,200 g, gestational age of <28 weeks and postnatal age of <5 days, with a risk of early onset sepsis. A median of 2.3 ml/kg of blood was collected from each neonate for the PK analysis. Hemoglobin (Hgb), hematocrit (Ht), basic hemodynamic parameters, total fluid intake, number of blood component transfusions and number of blood analysis for clinical indications were recorded. The control group consisted of 35 gestational age-, postnatal age- and birth weight-matched neonates who had not participated in a PK study., Results: We did not observe significant differences in any studied safety parameter, including Hgb and Ht values, between the two groups. Median number of blood component transfusions (n = 2 in both groups), median volume of transfused red blood cells (22 vs. 24 ml/kg in study vs. control group) and total daily fluid requirement were similar. The median calculated blood loss on clinical indications was 1.9 ml/24 h in the control group and 1.66 ml/24 h in the study group., Conclusions: In VLBW neonates, up to 2.3 ml/kg of blood (corresponding to 2.4% of calculated circulating blood volume) can be drawn for scientific purposes without compromising basic hemodynamic parameters, Hgb and Ht values, blood component transfusions or fluid requirements., (Copyright © 2011 S. Karger AG, Basel.)

Our objective was to describe the pharmacokinetics of meropenem in the peritoneal fluid (PF) of six patients with severe peritonitis and septic shock and to relate measured concentrations to the minimum inhibitory concentration of bacteria. Microdialysis catheters were placed into the peritoneal space during surgery. Meropenem concentrations in plasma and in PF were analyzed using compartmental modeling. Meropenem areas under the concentration-time curve were lower in PF than in plasma (average ratio, 73.8+/-15%) because of degradation confirmed ex vivo. Compartment modeling with elimination from a peripheral compartment described the data adequately, and was used to simulate steady-state concentration profiles in plasma and PF during various dosing regimens. At the currently recommended dosing regimen of 1 g infused over 20 min every 8 h, PF concentrations of meropenem in patients with severe peritonitis associated with septic shock reach values sufficient for antibacterial effects against susceptible, but not always against intermediately susceptible, bacteria.

Background: Thiopurine methyltransferase (TPMT) is a cytoplasmic enzyme involved in the metabolism of thiopurine drugs. To date, at least 25 single nucleotide polymorphisms have been reported in the TPMT gene, 23 of these are associated with reduced enzyme activity., Methods: The aim of the present study was to sequence the whole coding region of TPMT (exons 3-10) to identify known and novel TPMT sequence variants amongst healthy Estonians. Erythrocyte TPMT activity was also measured to carry out a genotype-phenotype comparison., Results: A total of 21 subjects were heterozygous for known TPMT alleles (*2, *3A, *3C, *9, *12). Several other previously described intronic and exon polymorphisms were identified. Three novel mutations were detected -30T>A in exon 3, 10A>G in intron 3, and 145A>G in intron 10. Association analysis revealed four markers (114T>A, 94T>A, 460G>A, 719A>G) whose frequencies were significantly different in intermediate (enzyme activity or=140 ng/mL/h) methylators (p<0.001). Haplotype analysis found one haplotype to be associated with intermediate TPMT activity., Conclusions: Our results point to several markers that predict reduced enzyme activity. None of the identified markers were associated with high enzyme activity.

Thiopurine S-methyltransferase (TPMT) is a biotransformation phase II enzyme responsible for the metabolic inactivation of thiopurine drugs. The present study was carried out to investigate the inhibitory potential of 15 nonsteroidal anti-inflammatory drugs (NSAIDs) on human TPMT activity in vitro. TPMT activity was measured in pooled human erythrocytes in the absence and presence of various NSAIDs using the previously published high-performance liquid chromatography-UV method. To determine the inhibition type and K(i) value for each compound, we performed kinetic analysis at five different inhibitor concentrations close to the IC(50) value obtained in preliminary experiments. Naproxen (K(i) = 52 microM), mefenamic acid (K(i) = 39 microM), and tolfenamic acid (K(i) = 50 microM) inhibited TPMT activity in a noncompetitive manner. The estimated K(i) values for the inhibition of TPMT by ketoprofen (K(i) = 172 microM) and ibuprofen (K(i) = 1043 microM) indicated that the propionic acid derivatives were relatively weak inhibitors of TPMT. Our results suggest that coadministration of thiopurines and various NSAIDs may lead to drug interactions.

Data on the pharmacokinetics (PKs) of penicillin G (PEN) in neonates date back to the 1970s and do not include data for very-low-birth-weight (VLBW) neonates. The aim of this study was to describe the steady-state PKs and to establish an optimal regimen for the dosing of PEN in neonates with gestational ages of less than 28 weeks and birth weights of less than 1,200 g. Two PEN dosing regimens were studied: 50,000 IU (30 mg)/kg of body weight every 12 h (q12h) (group 1; n = 9) and 25,000 IU (15 mg)/kg q12h (group 2; n = 9). Samples for PK analysis were drawn before the injection of PEN and at 2 and 30 min and 1.5, 4, 8, and 12 h after intravenous injection of the third to eighth PEN doses. The PEN concentration was measured by a high-performance liquid chromatography with UV detection technique. The median peak and trough concentrations of PEN were 147 mug/ml (lower and upper quartiles, 109 and 157 mug/ml, respectively) and 7 mug/ml (lower and upper quartiles, 5 and 13 mug/ml, respectively) after administration of the dose of 50,000 IU and 59 mug/ml (lower and upper quartiles, 53 and 78 mug/ml, respectively) and 3 mug/ml (lower and upper quartiles, 3 and 4 mug/ml, respectively) after administration of the dose of 25,000 IU. The PEN half-life (median and lower and upper quartiles for group 1, 3.9 h and 3.3 and 7.0 h, respectively; median and lower and upper quartiles for group 2, 4.6 h and 3.8 and 5.6 h, respectively) was longer in VLBW neonates than in adults and term infants. PEN renal clearance correlated with creatinine clearance (R(2) = 0.309596; P = 0.038). Only a median of 34% (lower and upper quartiles, 28 and 37%, respectively) of the administered dose was excreted in urine within the following 12 h. We conclude that in VLBW infants a PEN dose of 25,000 IU (15 mg)/kg q12h is safe and sufficient to achieve serum concentrations above the MIC(90) for group B streptococci for the entire dosing interval.

Thiopurine S-methyltransferase (TPMT; EC 2.1.1.67) is the key enzyme in the metabolism of thiopurine drugs. Determination of TPMT activity has been used for the individualization of thiopurine dose. We developed HPLC-UV assay for the determination of TPMT activity in human erythrocytes using 6-mercaptopurine as a substrate. Various extraction and chromatographic conditions were compared. In-house developed extraction with acetonitrile provided the lowest limit of quantification. TPMT activity was determined in 99 previously genotyped healthy Estonians. TPMT activity was expressed as the formation of 6-methylmercaptopurine ng/ml/h and normalized either to haemoglobin, haematocrit, erythrocyte count or protein content. The receiver-operating characteristic curve analysis revealed similar accuracy values for TPMT activity in predicting heterozygous and wild type individuals for each method of calculation. In healthy Estonians, TPMT activity varied from 21.5 to 129.6 ng/ml/h. For heterozygous individuals (n = 18), TPMT activity was 48.1 +/- 11.7 ng/ml/h. Wild type individuals (n = 81) revealed significantly higher TPMT activity 79.3 +/- 20.7 ng/ml/h (P < 0.001). This sensitive HPLC assay for quantitative determination of TPMT activity could easily be used in clinical settings. Under constant experimental conditions for haemolysate preparation no normalization is required.

The purpose of this study was to determine the CCR5-del32 allele frequency in type I (insulin-dependent) and type II (noninsulin-dependent) diabetes patients, and to test whether and how this mutation is associated with both types of diabetes. Thirty-eight type I diabetes and 111 type II diabetes patients' genotyping was performed by polymerase chain reaction assaying, and amplified products were digested with restriction enzyme EcoRI. The results were analyzed using statistical methods. No statistical differences were found in CCR5-del32 allele frequencies in types I and II diabetes patients compared with the control group of native Estonians. However, an association exists between CCR5 gene polymorphism and the clinical course of type I diabetes. In the case of wild-type CCR5, the disease starts at an earlier age. In type II diabetes, there was a difference between genotypes in morbidity to concomitant diseases, being higher in the CCR5 wild-type genotype.

P-glycoprotein (Pgp) is a member of the ABC-transporter family, and in humans, is encoded by the MDR1 gene. Recently, several single-nucleotide polymorphisms in the MDR1 gene were identified. The aim of the present study was to evaluate the effect of the MDR1 genetic polymorphisms G2677T and C3435T on Pgp activity in CD56+ and CD4+ peripheral blood cells. Using flow cytometry, rhodamine 123 (Rh123) efflux was determined in 46 male healthy volunteers. Median Rh123 fluorescence in control sample, after baseline dye uptake, was set as 100%. Rh123 fluorescence in efflux samples, exposed to different efflux periods, was used to calculate the percentage of Rh123 retained in the cells in comparison with control. There was no significant difference in Rh123 efflux in CD56+ cells after 5, 10, 15, and 30 min efflux between individuals with different MDR1 genotypes. Also, in CD4+ cells after 15, 30, 60, and 90 min, Rh123 efflux did not reveal statistically different results for the three genotypes at 2677 and 3435. Rh123 efflux was not enhanced by a 10-day rifampin administration, as determined in 15 individuals before and after rifampin treatment. In conclusion, we found no impact of the MDR1 G2677T and C3435T polymorphisms on Pgp activity in CD56+ and CD4+ peripheral blood lymphocytes.

Objective: The aim of the present study was to determine the frequency of the G816A, T825C, T1684C, and G4002A genetic polymorphisms of the human MRP1 gene in 230 healthy Caucasians. The functional assessment of these mutations was performed in fluorescence-activated cell sorting (FACS)-sorted peripheral blood CD4+ cells in a further 61 healthy volunteers by determining MRP1 mRNA expression., Methods: Genotyping of the MRP1 was carried out using real-time polymerase chain reaction (PCR) assays. Quantitative determination of the MRP1 mRNA expression was performed with real-time reverse-transcription-PCR., Results: A novel silent mutation G816A in exon 8 was found in this study. Allele frequencies of the 816A, 825C, 1684C, and 4002A were 4.1, 30.0, 80.0, and 28.3%, respectively. The frequency of the T825C polymorphism was comparable with that found in a previous Japanese study. In contrast, the frequency of the T1684C (OR 0.06, 95% CI 0.03-0.11, P<0.0001, vs Japanese) and the G4002A (OR 0.47, 95% CI 0.24-0.86, P=0.01, vs Japanese) was significantly rarer. The mean MRP1 mRNA expression in peripheral blood CD4+ cells was 1.03x10(4) +/- 3.8x10(3) molecules/ng of total RNA with an eightfold variation among individuals. However, MRP1 mRNA expression in CD4+ cells was not found to correlate with genetic polymorphisms investigated in this study., Conclusions: The genotypic results observed show an ethnic difference in the frequencies of the MRP1 genetic polymorphisms between Japanese and Caucasians. Further studies are required to better understand the clinical consequences of the MRP1 genetic variants.

Objectives: ATP-binding cassette (ABC) transporters extrude a wide variety of endogenous and exogenous compounds. In cancer cells, they are known to confer multidrug resistance. The aim of the present study was to determine the expression of the multidrug resistance-associated protein 1 (MRP1) and 2 (MRP2), which are members of the subfamily C of the ABC transporters family, in human hematopoietic cells., Methods: CD4+, CD8+, CD19+, and CD56+ cells were isolated from whole blood by FACS-sort in 20 healthy volunteers. MRP1 and MRP2 mRNA levels were quantified using real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assays on a LightCycler (Roche, Mannheim, Germany)., Results: The MRP1 mRNA exhibited the highest abundance in CD4+ cells (7.4 x 10(3)+/-3.19 x 10(3) molecules/ng of total RNA), followed by CD8+ > CD19+ > CD56+ cells. The MRP2 mRNA expression was highest in CD4+ cells (6.7 x 10(2)+/-2.84 x 10(2)), followed by CD8+ > CD56+ > CD19+ cells. No correlation between the MRP1 and MRP2 mRNA expression was observed. Interestingly, beta2-microglobulin mRNA expression in CD19+ cells was found to be twofold lower in comparison with other cells., Conclusions: On an mRNA level both MRP1 and MRP2 were expressed in peripheral blood cells, with more than sevenfold higher MRP1 expression in all cell populations investigated. The impact of the MRP1 and MRP2 transcription in these cells remains to study. The use of beta2-microglobulin as a housekeeping gene could have a critical impact on the interpretation of RT-PCR data.

Background: P-glycoprotein is a transmembrane efflux pump that extrudes a wide variety of drugs, thereby reducing their intracellular access. In humans, P-glycoprotein is encoded by the MDR1 gene. Recently, several single nucleotide polymorphisms in the MDR1 gene were identified. Moreover, it was postulated that, in addition to the full-length P-glycoprotein, a 'mini' P-glycoprotein was also present in lymphocytes., Materials and Methods: We investigated the effect of the genetic polymorphisms G2677T and C3435T in the MDR1 gene on MDR1 mRNA expression in FACS-sorted peripheral blood CD4+, CD8+, CD19+, and CD56+ cells. MDR1 mRNA expression was determined in 45 healthy individuals using a real-time quantitative RT-PCR., Results: We detected the highest expression of MDR1 mRNA in CD56+ cells, followed by CD8+ > CD4+ > CD19+ cells. However, genetic polymorphisms of the MDR1 gene failed to affect (P > 0.05) MDR1 mRNA levels in the peripheral blood lymphocytes. Furthermore, the transcript levels for the MDR1 N-terminal half were almost two-fold lower than that of the MDR1 C-terminal half in all cell populations investigated (P < 0.0001)., Conclusions: An almost two-fold difference in MDR1 C- and N-terminal half expressions supports the presence of mini-P-glycoprotein, an alternatively spliced form of the full-length molecule, in peripheral blood lymphocytes.

Aims: A noncoding single nucleotide polymorphism (SNP) in exon 26 3435C > T of the highly polymorphic MDR1 gene has been demonstrated to alter digoxin absorption after induction of the MDR1 gene product P-glycoprotein by rifampicin or after multiple oral dosing. The aim of the study was to investigate the effects of the major known MDR1 SNPs on the absorption of digoxin after a single oral dose in a large sample without drug pretreatment., Methods: Fifty healthy white male subjects between the age of 18 and 40 years were enrolled. Following an overnight fast, all subjects received a single oral dose of 1 mg digoxin. Venous blood samples were taken at intervals up to 4 h post dose to obtain a pharmacokinetic profile., Results: AUC(0,4 h), Cmax and tmax, used as indices of digoxin absorption, were not significantly different in any of the genotype groups tested. In particular, there was no significant difference between homozygous carriers of the C and T allele in exon 26 3435 (AUC(0,4 h) 9.24 and 9.38 micro g l-1 h, Cmax 4.73 and 3.81 micro g l-1, tmax 0,83 and 01.14 h)., Conclusions: This lack of effect of the major MDR1 SNPs on digoxin absorption might be explained by saturation of the maximum transport capacity of intestinal Pgp at the dose used.

Background: In comparison with neighbouring Scandinavian countries, the use of digoxin in Estonia is high. The present study was carried out to determine the use pattern of digoxin in Estonia and bioavailability of the local market leader preparation in comparison with Lanoxin., Method: Drug use data were evaluated from the annual reports of wholesale companies. For the bioequivalence study, a single-blind cross-over randomised two-way single-dose comparative bioavailability study was performed using 14 healthy volunteers. Digoxin concentrations in serum samples and urine were measured by chemiluminescent competitive immunoassay., Results: The use of digoxin in Estonia has increased by 35% during the period 1994-97. The steady market leader was the local generic drug. No statistically significant differences were found in any pharmacokinetic parameter between the generic preparation and Lanoxin. All parameters showed considerable variability. The total amount of drug excreted was the parameter with lowest inter- individual variation., Conclusion: The present study indicates that the generic digoxin preparation studied is bioequivalent to Lanoxin. The increasing use of digoxin in Estonia is not caused by low bioavailability of the local market leader but by therapeutic traditions.