Improving Data Collection in Pregnancy Safety Studies: Towards Standardisation of Data Elements in Pregnancy Reports from Public and Private Partners, A Contribution from the ConcePTION Project

INTRODUCTION AND OBJECTIVE

The ConcePTION project aims to improve the way medication use during pregnancy is studied. This includes exploring the possibility of developing a distributed data processing and analysis infrastructure using a common data model that could form a foundational platform for future surveillance and research. A prerequisite would be that data from various data access providers (DAPs) can be harmonised according to an agreed set of standard rules concerning the structure and content of the data. To do so, a reference framework of core data elements (CDEs) recommended for primary data studies on drug safety during pregnancy was previously developed. The aim of this study was to assess the ability of several public and private DAPs using different primary data sources focusing on multiple sclerosis, as a pilot, to map their respective data variables and definitions with the CDE recommendations framework.

METHODS

Four pregnancy registries (Gilenya, Novartis; Aubagio, Sanofi; the Organization of Teratology Information Specialists [OTIS]; Aubagio, Sanofi; the Dutch Pregnancy Drug Register, Lareb), two enhanced pharmacovigilance programmes (Gilenya PRIM, Novartis; MAPLE-MS, Merck Healthcare KGaA) and four Teratology Information Services (UK TIS, Jerusalem TIS, Zerifin TIS, Swiss TIS) participated in the study. The ConcePTION primary data source CDE includes 51 items covering administrative functions, the description of pregnancy, maternal medical history, maternal illnesses arising in pregnancy, delivery details, and pregnancy and infant outcomes. For each variable in the CDE, the DAPs identified whether their variables were: identical to the one mentioned in the CDE; derived; similar but with a divergent definition; or not available.

RESULTS

The majority of the DAP data variables were either directly taken (85%, n = 305/357, range 73-94% between DAPs) or derived by combining different variables (12%, n = 42/357, range 0-24% between DAPs) to conform to the CDE variables and definitions. For very few of the DAP variables, alignment with the CDE items was not possible, either because of divergent definitions (1%, n = 3/357, range 0-2% between DAPs) or because the variables were not available (2%, n = 7/357, range 0-4% between DAPs).

CONCLUSIONS

Data access providers participating in this study presented a very high proportion of variables matching the CDE items, indicating that alignment of definitions and harmonisation of data analysis by different stakeholders to accelerate and strengthen pregnancy pharmacovigilance safety data analyses could be feasible.

[Janus kinase inhibitors : new perspectives for precision medicine ?]

Janus kinase inhibitors (JAKi), such as tofacitinib, baricitinib, upadacitinib or ruxolitinib, are small molecules active on specific intracellular targets and used orally for the treatment of autoimmune or myeloproliferative diseases. Their remarkable therapeutic efficacy is offset by a significant risk of toxicities, essentially dose-dependent and a variable pharmacokinetic profile. The JAKi represent a new therapeutic armamentarium for treating autoimmune, myeloproliferative and inflammatory diseases (incl. COVID-19), but require thorough treatment individualization and close monitoring. Therapeutic Drug Monitoring (TDM) of JAKi could allow a personalized prescription and improve the efficacy-toxicity profile.

Four cases of audio-vestibular disorders related to immunisation with SARS-CoV-2 mRNA vaccines

OBJECTIVE

To gain medical insight into the clinical course and safety of otolaryngologic disorders following immunisation with severe acute respiratory coronavirus (SARS-CoV-2) mRNA-based vaccines.

DESIGN

Case description.

STUDY SAMPLE

We report four cases of transient audio-vestibular symptoms, which occurred shortly after inoculation of two BNT162b2 (Pfizer-BioNTech^®) and mRNA-1273 (Moderna®) vaccines.

RESULTS

Hearing loss was unilateral in all cases and recovered at least partially: it was associated with persistent gait instability in two cases, after 1 and 7 months. Trigger mechanisms underpinning audio-vestibular impairment remain uncertain. Immune tolerance mechanisms with off-target innate activation of T-lymphocytes may be involved in vestibulocochlear nerve disorders, as for other cranial nerves involvement.

CONCLUSIONS

The occurrence of audio-vestibular manifestations following mRNA-based vaccines needs ENT monitoring to support their causality in such rare vaccine-related adverse events. Audio-vestibular disorders appeared of transitory nature, including hearing loss, and should not deter further efforts in large-scale vaccination campaigns against SARS-CoV-2.

Symptoms and quality of life at 1-year follow up of patients discharged after an acute COVID-19 episode

AIM OF THE STUDY

Patients surviving COVID-19 have been described as being at risk of developing sequelae. We aimed to investigate and elicit persistent symptoms, emotional status and quality-of-life in patients discharged after an acute COVID-19 episode.

METHODS

Patient-reported outcome measures were collected during a telephone interview 30 days and 1 year after discharge. Patients' general health status was evaluated using questions based on their symptoms, emotional status was assessed using the items 9 to 12 of the HeartQoL questionnaire and quality of life was assessed at 1 year through the EQ-5D-5L. In patients with a history of cardiovascular disease, all 14 items of the HeartQoL questionnaire were completed to derive the HeartQoL global score.

RESULTS

Among 687 patients who survived after being hospitalised for COVID-19 at the University Hospitals of Geneva between 26 February and 26 April 2020, 184 (27%) and 165 (24%), respectively, participated in the follow-up at 30 days and 1 year. Of these 184 participants, 62% were male, median age was 58 years and 21% had a past medical history of cardiovascular disease. At one month after discharge, 61% (113/184) of patients presented fatigue and 28% (52/184) dyspnoea. One year after discharge, the main complaints were persistent fatigue in 27% (45/165) of patients, neurological problems in 17% (28/165) and dyspnoea in 14% (23/165). Eight percent (14/184) of patients declared being significantly worried 1 month after discharge and 5% (9/184) feeling depressed. The number of patients reporting being significantly worried or depressed at 1 year was lower. Regarding the quality of life at 1 year, the median EQ-5D-5L visual analogue scale score was 80 (interquartile range 70-90).

CONCLUSIONS

Approximately half of patients reported some symptoms 1 year after discharge following an acute episode of COVID-19. The predominant symptom was persistent fatigue both at 1-month and at 1-year follow-up. Emotional status and quality of life appeared satisfactory.

Hepatitis C prevalences in the psychiatric setting: Cost-effectiveness of scaling-up screening and direct-acting antiviral therapy

BACKGROUND & AIMS

Patients hospitalised because of mental illness often have risk factors for contracting HCV. Scaling-up HCV screening for all psychiatric inpatients as a case-detection strategy for viral elimination is underexplored. This study aimed to evaluate the cost-effectiveness of scaling-up HCV screening and treatment for psychiatry hospital admissions in Switzerland vs. the current standard-of-care risk-based approach, where only those with a history of substance misuse disorder are offered testing.

METHODS

HCV prevalence by history of substance misuse disorder was analysed in medical records from inpatient admissions to a Swiss psychiatry department. Cost-effectiveness was analysed from a healthcare provider perspective through a decision-tree screening model, using these HCV prevalence data. Model and parameter uncertainty were assessed using deterministic and probabilistic sensitivity analyses.

RESULTS

Prevalence of HCV in psychiatry inpatients with a history of substance misuse disorder (n = 1,013) was 25.7%, compared with 3.5% among the remaining inpatients (n = 3,535). Scaling up HCV screening and treatment for all psychiatry admissions was cost-effective vs. the risk-based approach, with an incremental cost-effectiveness ratio of US$9,188 per quality-adjusted life-year gained. The incremental cost-effectiveness ratio remained cost-effective considering a HCV prevalence as low as 0.07%. The population-level net monetary benefit of the generalised screening approach was US$435,156,348, with 917 additional patients per year detected and treated at a cost of US$3,294 per person (vs. US$2,122 under risk-based screening).

CONCLUSIONS

Scaling up HCV screening and treatment at diagnosis with all-oral, interferon-free regimens as a generalised approach for psychiatric admissions was cost-effective and could support reaching World Health Organization targets for HCV elimination by 2030.

LAY SUMMARY

Patients hospitalised because of mental illness often have risk factors for HCV. We found that testing all psychiatry patients in hospital for HCV was cost-effective compared with testing only patients who have a history of substance misuse. Scaling up HCV testing and treatment could help to wipe out HCV.

Mortality and high risk of major adverse events in patients with COVID-19 and history of cardiovascular disease

OBJECTIVE

History of cardiovascular diseases (CVDs) may influence the prognosis of patients hospitalised for COVID-19. We investigated whether patients with previous CVD have increased risk of death and major adverse cardiovascular event (MACE) when hospitalised for COVID-19.

METHODS

We included 839 patients with COVID-19 hospitalised at the University Hospitals of Geneva. Demographic characteristics, medical history, laboratory values, ECG at admission and medications at admission were collected based on electronic medical records. The primary outcome was a composite of in-hospital mortality or MACE.

RESULTS

Median age was 67 years, 453 (54%) were males and 277 (33%) had history of CVD. In total, 152 (18%) died and 687 (82%) were discharged, including 72 (9%) who survived a MACE. Patients with previous CVD were more at risk of composite outcomes 141/277 (51%) compared with those without CVD 83/562 (15%) (OR=6.0 (95% CI 4.3 to 8.4), p<0.001). Multivariate analyses showed that history of CVD remained an independent risk factor of in-hospital death or MACE (OR=2.4; (95% CI 1.6 to 3.5)), as did age (OR for a 10-year increase=2.2 (95% CI 1.9 to 2.6)), male gender (OR=1.6 (95% CI 1.1 to 2.3)), chronic obstructive pulmonary disease (OR=2.1 (95% CI 1.0 to 4.2)) and lung infiltration associated with COVID-19 at CT scan (OR=1.9 (95% CI 1.2 to 3.0)). History of CVD (OR=2.9 (95% CI 1.7 to 5)), age (OR=2.5 (95% CI 2.0 to 3.2)), male gender (OR=1.6 (95% CI 0.98 to 2.6)) and elevated C reactive protein (CRP) levels on admission (OR for a 10 mg/L increase=1.1 (95% CI 1.1 to 1.2)) were independent risk factors for mortality.

CONCLUSION

History of CVD is associated with higher in-hospital mortality and MACE in hospitalised patients with COVID-19. Other factors associated with higher in-hospital mortality are older age, male sex and elevated CRP on admission.

[Pharmacogenomics : a toolbox to improve drug prescription]

As a result of advances in pharmacogenomics (PGx), the paradigm that a single dose of a drug is extrapolated to an entire population is set to change. Personalising drug prescriptions according to individual genomic determinants would make it possible to increase the effectiveness and tolerance of treatments. In Switzerland, any doctor can prescribe validated PGx tests for five actionable drugs : abacavir, carbamazepine, thiopurines [azathioprine], fluoropyrimidines [5-FU, capecitabine] and irinotecan. Such an approach presupposes that PGx data are shared with trained clinicians and that prescribing aids can guide them.

Modelling the Impact and Cost-effectiveness of Extended Hepatitis C Virus Screening and Treatment with Direct-acting Antivirals in a Swiss Custodial Setting

BACKGROUND

Hepatitis C virus (HCV) among people living in detention (PLD) is typically high in many countries including Switzerland, where it is estimated that the HCV prevalence rate is between 5.7% and 6.2%. In Switzerland, the existing screening strategy involves routine screening of PLD who indicate they are from HCV high-risk populations based on questionnaire responses upon entry to the detention center, rather than an offer to screen all PLD.

METHODS

A cost-effectiveness analysis from a Swiss healthcare provider perspective was conducted by combining a 5-year decision tree screening model with results from a Markov model of HCV treatment outcomes. This model explored the cost-effectiveness of increased HCV screening to cover all PLD compared to the current approach, using a standard test package and subsequent treatment with a single-tablet regimen in Swiss custodial settings. Sensitivity and scenario analyses examined the uncertainty of results.

RESULTS

At the willingness-to-pay threshold of 100 000 Swiss Francs (CHF) per quality-adjusted life-year (QALY), comprehensive general screening was cost-effective compared to current risk-based screening, with a base case incremental cost-effectiveness ratio of CHF 14 312 per QALY. The net monetary benefit of screening the whole PLD population was CHF 23 298 046 and CHF 4298 per person. The proportion of PLD tested was predicted to increase from 13.6% to 67.0% under comprehensive screening.

CONCLUSION

The results showed that comprehensive screening strategies in detention centers in Switzerland can be cost-effective, with the probabilistic sensitivity analysis estimating an 82.3% probability of cost-effectiveness.

Emerging Concepts and Applied Machine Learning Research in Patients with Drug-Induced Repolarization Disorders

The paper presents a review of current research to develop predictive models for automated detection of drug-induced repolarization disorders and shows a feasibility study for developing machine learning tools trained on massive multimodal datasets of narrative, textual and electrocardiographic records. The goal is to reduce drug-induced long QT and associated complications (Torsades-de-Pointes, sudden cardiac death), by identifying prescription patterns with pro-arrhythmic propensity using a validated electronic application for the detection of adverse drug events with data mining and natural language processing; and to compute individual-based predictive scores in order to further identify clinical conditions, concomitant diseases, or other variables that correlate with higher risk of pro-arrhythmic situations.

Direct-acting antiviral interactions with opioids, alcohol or illicit drugs of abuse in HCV-infected patients

The hepatitis C virus (HCV) prevalence is extremely high in patients who consume and inject illicit drugs. Concerns about poor adherence and fear of interaction with drugs of abuse could constitute further disincentive for treatment initiation in these patients. We discussed the pharmacokinetics (PKs) and pharmacodynamics (PD) of currently prescribed direct antiviral agents (NSA5 inhibitors: daclatasvir, elbasvir, ledipasvir, pibrentasvir, velpatasvir; NS5B inhibitor: sofosbuvir; NS3/4A protease inhibitors: glecaprevir, grazoprevir, voxilaprevir) and most common substances of abuse (opioids: buprenorphine, fentanyl, heroin, methadone, morphine, oxycodone; stimulants: amphetamines, cathinones, cocaine; cannabinoids; ethanol). Overall, most direct-acting antivirals (DAAs) are substrates and inhibitors of the transmembrane transporter P-glycoprotein (P-gp), and several of them are metabolized by cytochrome P450 enzymes. Clinically relevant interactions are associated with P-gp and CYP3A modulators. Most substances of abuse are eliminated by Phase I and Phase II metabolizing enzymes, but none of them are either major inhibitors or inducers. PK studies did not show any relevant interactions between DAA and methadone or buprenorphine. Based on pharmacological considerations, neither efficacy loss nor adverse drug event associated with detrimental interaction are expected with opioids, stimulants, cannabinoids and ethanol. In summary, our literature review shows that the interaction potential of DAA with most opioids and illicit drugs is limited and should not be a hurdle to the initiate DAA.

Increasing hepatitis C virus screening in people who inject drugs in Switzerland using rapid antibody saliva and dried blood spot testing: A cost-effectiveness analysis

People who inject drugs (PWID) are a key high-risk group for Hepatitis C Virus (HCV) infection due to the sharing of needles and drug-preparation equipment. However, only approximately 50% of PWID are currently screened for HCV in Switzerland. At present, screening of PWID occurs in general practice via venepuncture. Compared to venepuncture, screening via rapid antibody saliva and dried blood spot (DBS) tests is well adapted to PWID, who typically have difficult venous access. The cost-effectiveness of an increased access screening programme of PWID (increased screening using rapid antibody saliva tests and DBS tests [semi-quantitative viraemia and viral genotype]) was analysed through a decision tree screening model combined with the outputs of a Markov treatment model. Sensitivity and scenario analyses examined the uncertainty of results. At a willingness to pay (WTP) threshold of CHF 100 000 (USD 105 000) per quality-adjusted life year (QALY), the increased access screening programme was cost-effective compared to current screening, with a base case incremental cost-effectiveness ratio of CHF 7 940 (USD 8337) per QALY. The net monetary benefit was CHF 959 802 668 (USD 1 007 792 801) for the PWID population and CHF 94 469 (USD 99 192) per person. The increased access screening programme had a 97.0% probability of being cost-effective compared to the current screening method at the WTP threshold of CHF 100 000 (USD 105 000). The results showed an increased access screening programme that uses tests which are better suited to the PWID population to be more cost-effective, due to the increased uptake that rapid antibody saliva and DBS tests generate.

Blood-borne and sexually transmitted infections: a cross-sectional study in a Swiss prison

Background

Incarcerated people carry a high burden of infection, including blood-borne diseases (BBDs). It is also known that one million people contract a sexually transmitted infection (STI) every day worldwide, which represents a global public health challenge. However, data regarding the prevalence of STIs and the risk factors among incarcerated populations are lacking. The objective of this study was to determine the prevalence and associated factors of BBDs and STIs among detainees in the largest pre-trial prison in Switzerland.

Methods

In a cross-sectional study conducted at the Champ-Dollon pre-trial prison, 273 male detainees answered a standardized questionnaire and were screened for syphilis, herpes simplex virus 2 (HSV-2), HIV, and hepatitis C (HCV). Prevalence rates and associations of BBDs and STIs with risk factors were computed.

Results

Most participants (90.9%) were migrants from outside Western Europe, and 5.9% were injecting drug users. HCV was diagnosed among 6.2% of participants (antibody prevalence). The prevalence of HCV was higher among injecting drug users (81.2%) than non-injectors (1.6%). The prevalence of HIV, syphilis, and HSV-2 was 0.4%, 1.1%, and 22.4%, respectively. HCV was associated with a history of injecting drug use and HSV-2 with a lower education level and being older than 26 years.

Conclusions

This study showed the infection prevalence of 2–9 times higher among detainees than in the Swiss community. It also illustrated that these infections are associated with sociodemographic and risk factors. Therefore, the prison environment offers an opportunity to strengthen infectious disease control programs targeting specific subgroups of at-risk people. Such programs would benefit both the prison population and broader society.

Early Discharge in Low-Risk Patients Hospitalized for Acute Coronary Syndromes: Feasibility, Safety and Reasons for Prolonged Length of Stay

Introduction

Length of hospital stay (LHS) is an indicator of clinical effectiveness. Early hospital discharge (≤72 hours) is recommended in patients with acute coronary syndromes (ACS) at low risk of complications, but reasons for prolonged LHS poorly reported.

Methods

We collected data of ACS patients hospitalized at the Geneva University Hospitals from 1st July 2013 to 30th June 2015 and used the Zwolle index score to identify patients at low risk (≤ 3 points). We assessed the proportion of eligible patients who were successfully discharged within 72 hours and the reasons for prolonged LHS. Outcomes were defined as adherence to recommended therapies, major adverse events at 30 days and patients' satisfaction using a Likert-scale patient-reported questionnaire.

Results

Among 370 patients with ACS, 255 (68.9%) were at low-risk of complications but only 128 (50.2%)were eligible for early discharge, because of other clinical reasons for prolonged LHS (e.g. staged coronary revascularization, cardiac monitoring) in 127 patients (49.8%). Of the latter, only 45 (35.2%) benefitted from an early discharge. Reasons for delay in discharge in the remaining 83 patients (51.2%) were mainly due to delays in additional investigations, titration of medical therapy, admission or discharge during weekends. In the early discharge group, at 30 days, only one patient (2.2%) had an adverse event (minor bleeding), 97% of patients were satisfied by the medical care.

Conclusion

Early discharge was successfully achieved in one third of eligible ACS patients at low risk of complications and appeared sufficiently safe while being overall appreciated by the patients.

Drug Pricing Evolution in Hepatitis C

Objective

We aimed to determine the association between the stepwise increase in the sustained viral response (SVR) and Swiss and United States (US) market prices of drug regimens for treatment-naive, genotype 1 chronic hepatitis C virus (HCV) infection in the last 25 years. We identified the following five steps in the development of HCV treatment regimens: 1) interferon (IFN)-α monotherapy in the early '90s, 2) IFN-α in combination with ribavirin (RBV), 3) pegylated (peg) IFN-α in combination with RBV, 4) the first direct acting antivirals (DAAs) (telaprevir and boceprevir) in combination with pegIFN-α and RBV, and 5) newer DAA-based regimens, such as sofosbuvir (which is or is not combined with ledipasvir) and fixed-dose combination of ritonavir-boosted paritaprevir and ombitasvir in combination with dasabuvir.

Design

We performed a linear regression and mean cost analysis to test for an association between SVRs and HCV regimen prices. We conducted a sensitivity analysis using US prices at the time of US drug licensing. We selected randomized clinical trials of drugs approved for use in Switzerland from 1997 to July 2015 including treatment-naïve patients with HCV genotype 1 infection.

Results

We identified a statistically significant positive relationship between the proportion of patients achieving SVRs and the costs of HCV regimens in Switzerland (with a bivariate ordinary least square regression yielding an R2 measure of 0.96) and the US (R2 = 0.95). The incremental cost per additional percentage of SVR was 597.14 USD in Switzerland and 1,063.81 USD in the US.

Conclusion

The pricing of drugs for HCV regimens follows a value-based model, which has a stable ratio of costs per achieved SVR over 25 years. Health care systems are struggling with the high resource use of these new agents despite their obvious long-term advantages for the overall health of the population. Therefore, the pharmaceutical industry, health care payers and other stakeholders are challenged with finding new drug pricing schemes to treat the entire population infected with HCV.

[Rethinking the reimbursement policy of direct acting antivirals against chronic hepatitis C]

New direct-acting antivirals (DAA) against hepatitis C virus (HCV) have led to a therapeutic revolution in HCV management and virological cure rates approaching 100% while potentially avoiding significant complications of HCV (first cause of liver transplantation). We estimated the price of sustained virological response (SVR) depending on treatment strategy and patient profile. Costs of treatment with recent DAAs being so high, the accessibility to those drugs for the majority of subjects is hitherto limited to advanced stages of hepatitis C. This current situation increases the inequity and strengthens the dominant position of insurers and pharmaceutical companies with a rationing of care. We suggest herein global approaches from a population-level and health-care perspective aiming to reduce the prevalence, morbidity, and mortality related to HCV.

[Teaching students guidelines: prescription in the practice setting]

The aim of this article is to help primary care teachers to instruct students' recommendations for drug prescription. Teaching drug prescription covers many aspects of primary care physicians' profession: establishing the correct diagnosis, choosing the appropriate treatment for any individual patient, negotiating with the patient concrete ways of taking the treatment, handling the necessary pharmacologic knowledge or existing tools that help treatment choice and communicating efficiently with the patient. The WHO 6-step method is presented. It helps to clarify the complexity of medical prescription so as to make it understandable for the student.

Cost-effectiveness of cardiovascular magnetic resonance in the diagnosis of coronary heart disease: an economic evaluation using data from the CE-MARC study

OBJECTIVE

To evaluate the cost-effectiveness of diagnostic strategies for coronary heart disease (CHD) derived from the CE-MARC study.

DESIGN

Cost-effectiveness analysis using a decision analytic model to compare eight strategies for the diagnosis of CHD.

SETTING

Secondary care out-patients (Cardiology Department).

PATIENTS

Patients referred to cardiologists for the further evaluation of symptoms thought to be angina pectoris.

INTERVENTIONS

Eight different strategies were considered, including different combinations of exercise treadmill testing (ETT), single-photon emission CT (SPECT), cardiovascular magnetic resonance (CMR) and coronary angiography (CA).

MAIN OUTCOME MEASURES

Costs expressed as UK sterling in 2010-2011 prices and health outcomes in quality-adjusted life-years (QALYs). The time horizon was 50 years.

RESULTS

Based on the characteristics of patients in the CE-MARC study, only two strategies appear potentially cost-effective for diagnosis of CHD, both including CMR. The choice is between two strategies: one in which CMR follows a positive or inconclusive ETT, followed by CA if CMR is positive or inconclusive (Strategy 3 in the model); and the other where CMR is followed by CA if CMR is positive or inconclusive (Strategy 5 in the model). The more cost-effective of these two rests on the threshold cost per QALY gained below which health systems define an intervention as cost-effective. Strategy 3 appears cost-effective at the lower end of the threshold range used in the UK (£20 000 per QALY gained), while Strategy 5 appears cost-effective at the higher end of the threshold range (£30 000 per QALY). The results are robust to various sources of uncertainty although prior likelihood of CHD requiring revascularisation and the rate at which false negative patients are eventually appropriately identified do impact upon the results.

CONCLUSIONS

The CE-MARC study showed that CMR had superior diagnostic accuracy to SPECT and concluded that CMR should be more widely used in the investigation of patients with CHD. The economic evaluation results show that using CMR is also a cost-effective strategy and supports the wider adoption of this modality.

Patented drug extension strategies on healthcare spending: a cost-evaluation analysis

BACKGROUND

Drug manufacturers have developed "evergreening" strategies to compete with generic medication after patent termination. These include marketing of slightly modified follow-on drugs. We aimed to estimate the financial impact of these drugs on overall healthcare costs and also to examine the impact of listing these drugs in hospital restrictive drug formularies (RDFs) on the healthcare system as a whole ("spillover effect").

METHODS AND FINDINGS

We used hospital and community pharmacy invoice office data in the Swiss canton of Geneva to calculate utilisation of eight follow-on drugs in defined daily doses between 2000 and 2008. "Extra costs" were calculated for three different scenarios assuming replacement with the corresponding generic equivalent for prescriptions of (1) all brand (i.e., initially patented) drugs, (2) all follow-on drugs, or (3) brand and follow-on drugs. To examine the financial spillover effect we calculated a monthly follow-on drug market share in defined daily doses for medications prescribed by hospital physicians but dispensed in community pharmacies, in comparison to drugs prescribed by non-hospital physicians in the community. Estimated "extra costs" over the study period were €15.9 (95% CI 15.5; 16.2) million for scenario 1, €14.4 (95% CI 14.1; 14.7) million for scenario 2, and €30.3 (95% CI 29.8; 30.8) million for scenario 3. The impact of strictly switching all patients using proton-pump inhibitors to esomeprazole at admission resulted in a spillover "extra cost" of €330,300 (95% CI 276,100; 383,800), whereas strictly switching to generic cetirizine resulted in savings of €7,700 (95% CI 4,100; 11,100). Overall we estimated that the RDF resulted in "extra costs" of €503,600 (95% CI 444,500; 563,100).

CONCLUSIONS

Evergreening strategies have been successful in maintaining market share in Geneva, offsetting competition by generics and cost containment policies. Hospitals may be contributing to increased overall healthcare costs by listing follow-on drugs in their RDF. Therefore, healthcare providers and policy makers should be aware of the impact of evergreening strategies.

Liver kidney microsomal type 1 antibodies reduce the CYP2D6 activity in patients with chronic hepatitis C virus infection

Liver kidney microsomal type 1 (LKM-1) antibodies have been shown to decrease the CYP2D6 activity in vitro and are present in a minority of patients with chronic hepatitis C infection. We investigated whether LKM-1 antibodies might reduce the CYP2D6 activity in vivo. All patients enrolled in the Swiss Hepatitis C Cohort Study and tested for LKM-1 antibodies were assessed (n = 1723): 10 eligible patients were matched with patients without LKM-1 antibodies. Patients were genotyped for CYP2D6 variants to exclude individuals with a poor metabolizer genotype. CYP2D6 activity was measured by a specific substrate using the dextromethorphan/dextrorphan metabolic ratio to classify patients into four activity phenotypes. All patients had a CYP2D6 extensive metabolizer genotype. The observed phenotype was concordant with the CYP2D6 genotype in most LKM-negative patients, whereas only three LKM-1 positive patients had a concordant phenotype (six presented an intermediate and one a poor metabolizer phenotype). The median DEM/DOR ratio was sixfold higher in LKM-1 positive than in LKM-1 negative patients (0.096 vs. 0.016, P = 0.004), indicating that CYP2D6 metabolic function was significantly reduced in the presence of LKM-1 antibodies. In chronic hepatitis C patients with LKM-1 antibodies, the CYP2D6 metabolic activity was on average reduced by 80%. The impact of LKM-1 antibodies on CYP2D6-mediated drug metabolism pathways warrants further translational studies.

[Psychiatric patients and QT interval monitoring]

Cardiovascular morbidity and mortality are higher in psychiatric patients than in the general population. In schizophrenic patients without cardiovascular history, long QT interval is a major risk factor for torsades de pointe and for sudden death. QT interval prolongation is a severe and underestimated dose-dependent adverse reaction triggered by several psychotropic drugs and by clinical situations such as polymedication, methadone maintenance treatment, electrolytic disturbances, cardiovascular history and congenital long QT syndromes. Systematic measurement of QT interval is recommended when psychotropic medications known to prolong it are introduced, as well as in clinical situations at risk. Stereoselective R-methadone administration (chiral switching) contributes to reduce the risk of QT prolongation.

Membrane transporter proteins: a challenge for CNS drug development

Drug transporters are membrane proteins present in various tissues such as the lymphocytes, intestine, liver, kidney, testis, placenta, and central nervous system. These transporters play a significant role in drug absorption and distribution to organic systems, particularly if the organs are protected by blood-organ barriers, such as the blood-brain barrier or the maternal-fetal barrier. In contrast to neurotransmitters and receptor-coupled transporters or other modes of interneuronal transmission, drug transporters are not directly involved in specific neuronal functions, but provide global protection to the central nervous system. The lack of capillary fenestration, the low pinocytic activity, and the tight junctions between brain capillary and choroid plexus endothelial cells represent further gatekeepers limiting the entrance of endogenous and exogenous compounds into the central nervous system. Drug transport is a result of the concerted action of efflux and influx pumps (transporters) located both in the basolateral and apical membranes of brain capillary and choroid plexus endothelial cells. By regulating efflux and influx of endogenous or exogenous substances, the blood-brain barrier and, to a lesser extent, the blood-cerebrospinal barrier in the ventricles, represents the main interface between the central nervous system and the blood, ie, the rest of the body. As drug distribution to organs is dependent on the affinity of a substrate for a specific transport system, membrane transporter proteins are increasingly recognized as a key determinant of drug disposition. Many drug transporters are members of the adenosine triphosphate (ATP)-binding cassette (ABC) transporter superfamily or the solute-linked carrier (SLC) class. The multidrug resistance protein MDR1 (ABCB1), also called P-glycoprotein, the multidrug resistance-associated proteins MRP1 (ABCC1) and MRP2 (ABCC2), and the breast cancer-resistance protein BCRP (ABCG2) are ATP-dependent efflux transporters expressed in the blood-brain barrier. They belong to the superfamily of ABC transporters, which export drugs from the intracellular to the extracellular milieu. Members of the SLC class of solute carriers include, for example, organic ion transporting peptides, organic cation transporters, and organic ion transporters. They are ATP-independent polypeptides principally expressed at the basolateral membrane of brain capillary and choroid plexus endothelial cells that also mediate drug transport through central nervous system barriers.

Membrane transporter proteins: a challenge for CNS drug development

Drug transporters are membrane proteins present in various tissues such as the lymphocytes, intestine, liver, kidney, testis, placenta, and central nervous system. These transporters play a significant role in drug absorption and distribution to organic systems, particularly if the organs are protected by blood-organ barriers, such as the blood-brain barrier or the maternal-fetal barrier. In contrast to neurotransmitters and receptor-coupled transporters or other modes of interneuronal transmission, drug transporters are not directly involved in specific neuronal functions, but provide global protection to the central nervous system. The lack of capillary fenestration, the low pinocytic activity and the tight junctions between brain capillary and choroid plexus endothelial cells represent further gatekeepers limiting the entrance of endogenous and exogenous compounds into the central nervous system. Drug transport is a result of the concerted action of efflux and influx pumps (transporters) located both in the basolateral and apical membranes of brain capillary and choroid plexus endothelial cells. By regulating efflux and influx of endogenous or exogenous substances, the blood-brain barrier and, to a lesser extent the blood-cerebrospinal barrier in the ventricles, represents the main interface between the central nervous system and the blood, i.e., the rest of the body. As drug distribution to organs is dependent on the affinity of a substrate for a specific transport system, membrane transporter proteins are increasingly recognized as a key determinant of drug disposition. Many drug transporters are members of the adenosine triphosphate (ATP)-binding cassette (ABC) transporter superfamily or the solute-linked carrier (SLC) class. The multidrug resistance protein MDR1 (ABCB1), also called P-glycoprotein, the multidrug resistance-associated proteins MRP1 (ABCC1) and MRP2 (ABCC2), and the breast cancer-resistance protein BCRP (ABCG2) are ATP-dependent efflux transporters expressed in the blood-brain barrier They belong to the superfamily of ABC transporters, which export drugs from the intracellular to the extracellular milieu. Members of the SLC class of solute carriers include, for example, organic ion transporting peptides, organic cation transporters, and organic ion transporters. They are ATP-independent polypeptides principally expressed at the basolateral membrane of brain capillary and choroid plexus endothelial cells that also mediate drug transport through central nervous system barriers.

[Antihypertensive therapy and drug-drug interactions]

Adverse drug reactions (ADR) have increasing clinical implications and are a permanent challenge for general practitioners. Data suggest that ADR cause 3 to 18% of all hospital admissions with potentially serious consequences. Polymedication, female sex, multiple pathologies with age-related changes are predisposing factors. Antihypertensive drugs with a low bioavailability, a high protein binding capacity and specific elimination pathways are particularly prone to pharmacokinetic interactions. ACE-inhibitors, atenolol, moxonidine and diuretics have few pharmacokinetic interactions. Calcium channel blockers and beta-blockers are associated with an increased risk of pharmacokinetic drug-drug interactions. Diltiazem and verapamil are particularly prone to interactions, as they strongly inhibit the elimination of drugs undergoing the CYP3A4 and P-glycoprotein pathways.

[The selection of a drug in a defined therapeutic class: the case of the HMG-CoA reductase inhibitors]

The HMG-CoA reductase inhibitors have similar therapeutic targets and indications. However, their potential pharmacokinetic drug-drug interaction profile may play a significant role in their safety profile in polymedicated and polymorbid patients and can serve as a selection criterion. If their utility is clearly demonstrated in selected conditions, their safety profile remains of concern. Beside dose-related hepatic and muscular injury, other rare and important adverse drug reactions have been reported after prolonged administration such as polyneuropathy, fibrotic interstitial pulmonary disease and lupus-like syndrome. Teratogenicity has also been associated with statin therapy.

Pharmacokinetics of high doses of intramuscular and oral heroin in narcotic addicts

BACKGROUND

In several countries medical prescription of diacetylmorphine is currently being evaluated as a treatment option for heavily dependent narcotic addicts. Because of damaged veins, many patients administer diacetylmorphine intramuscularly or orally. Therefore we characterized the pharmacokinetics of intramuscular and oral diacetylmorphine in the high dose range usually required in narcotic addicts.

METHODS

Three intramuscular doses, 3 oral doses, and 1 intravenous dose of diacetylmorphine and oral and intravenous test doses of deuterium-labeled morphine (morphine-N-methyl-d3 [morphine-d3]) were administered to 8 heroin-addicted patients. Arterial plasma concentrations of diacetylmorphine, monoacetylmorphine, morphine, morphine-3-glucuronide, morphine-6-glucuronide, and morphine-d3 were measured by liquid chromatography-mass spectrometry.

RESULTS

Intramuscularly administered diacetylmorphine (</=200-250 mg) exhibited linear diacetylmorphine, monoacetylmorphine, and morphine kinetics and resulted in sustained diacetylmorphine exposures (bioavailability, 380% +/- 157% [mean +/- SD]) and in lower and delayed peak monoacetylmorphine and morphine concentrations as compared with intravenous administration. Oral diacetylmorphine (</=600 mg) yielded negligible systemic diacetylmorphine and monoacetylmorphine exposures but was associated with linear kinetics and high bioavailabilities for morphine (67% +/- 19%), morphine-3-glucuronide (205% +/- 52%), and morphine-6-glucuronide (180% +/- 61%). In addition, oral diacetylmorphine was absorbed more rapidly and to a greater extent than a concomitant test dose of morphine-d3.

CONCLUSIONS

On the basis of the linear pharmacokinetics, the high bioavailability of intramuscular diacetylmorphine, and the rapid and extended morphine absorption from oral diacetylmorphine, the intramuscular and oral routes can be recommended as safe and feasible alternatives to the intravenous route for medical prescription of diacetylmorphine.

Relationship between corneal temperature and finger temperature

BACKGROUND

Because the temperature of the body surface depends largely on local blood flow, temperature measurements might provide information on the latter.

OBJECTIVE

To evaluate the relationship between corneal temperature and finger temperature.

METHODS

Corneal, finger, and body core temperatures were measured in a relatively unselected population of 266 white persons. Excluded were persons taking topical eye medication or with corneal inflammatory signs. Corneal and finger temperatures were measured on 1 randomly selected side of the body by means of a noncontact infrared thermometer. As a measure of body temperature, the tympanic temperature was measured by means of a noncontact infrared ear thermometer. A total of 124 females and 142 males were examined.

RESULTS

A correlation analysis in a least squares regression model was highly significant (R = 0.67; P<.001), with corneal temperature as the dependent variable and environmental, tympanic, and finger temperatures and age and sex as predicting variables. All variables contributed significantly to prediction of the corneal temperature. The corrected mean corneal temperature after adjusting for environmental, tympanic, and finger temperatures and for age of participants was 0.16 degrees C higher in male participants (P = .002).

CONCLUSIONS

Corneal temperature correlates with finger temperature even after adjusting for environmental and tympanic temperatures and for the age and sex of participants. A possible cause for these findings are some parallelisms in blood-flow regulation in the finger and the eye.