A new pathway for penicillin delabeling in Norway.

Background: Penicillin allergy is self-reported by 3-10% of patients admitted to hospital. The label is wrong in 90% of the cases and has severe health implications. Penicillin-delabeling can reverse the negative effects of the label, and pathways adapted to local practice are needed. No tools are available in Norway for penicillin delabeling outside an allergy clinic. Objective: To create and validate the first penicillin delabeling pathway applicable outside an allergy clinic in Norway. Methods: An interdisciplinary taskforce created a penicillin allergy delabeling program (PAD) adapted to the Norwegian health care system. This was validated in a prospective, single-center study. Very low-risk and low-risk patients underwent a direct oral penicillin challenge and high-risk patients were referred for allergologic evaluation. Results: One-hundred forty-nine patients declaring penicillin allergy were included. Seventy-four (50%) were very-low- and low risk patients suitable for a direct oral penicillin challenge resulting in only 1 mild reaction. Sixty high-risk patients were eligible for an oral penicillin challenge after allergologic evaluation; 3 patients reacted non-severely. Conclusion: We have created and demonstrated feasibility of the first penicillin delabeling program (PAD) applicable in a hospital setting outside an allergy clinic in Norway. Our data suggest this is safe and beneficial, with 49% patients delabeled through a direct oral penicillin challenge, performed without any serious adverse events, and an overall 87% delabeling rate.

Nurses as adverse drug reaction reporting advocates.

Adverse drug reactions (ADRs) is a challenge in modern healthcare, particularly given the increasing complexity of drug therapy, an ageing population, rising multimorbidity, and a high patient turnover. The core activity of detecting potential ADRs over the last half century has been spontaneous reporting systems. A recent Norwegian regulation commits healthcare professionals other than physicians and dentists to report serious ADRs. In this discussion paper, we share our preliminary experience with a training programme using nurses as ADR advocates to stimulate ADR reporting among the clinical staff in a hospital department.

SonoVue® vs. Sonazoid™ vs. Optison™: Which Bubble Is Best for Low-Intensity Sonoporation of Pancreatic Ductal Adenocarcinoma?

The use of ultrasound and microbubbles to enhance therapeutic efficacy (sonoporation) has shown great promise in cancer therapy from in vitro to ongoing clinical studies. The fastest bench-to-bedside translation involves the use of ultrasound contrast agents (microbubbles) and clinical diagnostic scanners. Despite substantial research in this field, it is currently not known which of these microbubbles result in the greatest enhancement of therapy within the applied conditions. Three microbubble formulations-SonoVue®, Sonazoid™, and Optison™-were physiochemically and acoustically characterized. The microbubble response to the ultrasound pulses used in vivo was simulated via a Rayleigh-Plesset type equation. The three formulations were compared in vitro for permeabilization efficacy in three different pancreatic cancer cell lines, and in vivo, using an orthotopic pancreatic cancer (PDAC) murine model. The mice were treated using one of the three formulations exposed to ultrasound from a GE Logiq E9 and C1-5 ultrasound transducer. Characterisation of the microbubbles showed a rapid degradation in concentration, shape, and/or size for both SonoVue® and Optison™ within 30 min of reconstitution/opening. Sonazoid™ showed no degradation after 1 h. Attenuation measurements indicated that SonoVue® was the softest bubble followed by Sonazoid™ then Optison™. Sonazoid™ emitted nonlinear ultrasound at the lowest MIs followed by Optison™, then SonoVue®. Simulations indicated that SonoVue® would be the most effective bubble using the evaluated ultrasound conditions. This was verified in the pre-clinical PDAC model demonstrated by improved survival and largest tumor growth inhibition. In vitro results indicated that the best microbubble formulation depends on the ultrasound parameters and concentration used, with SonoVue® being best at lower intensities and Sonazoid™ at higher intensities.

A Patient With Sepsis-Induced Multiorgan Failure and Increasing Serum Methadone Concentration: A Case Study.

ABSTRACT: The authors describe a patient with substance use disorder admitted to the hospital with septic shock and multiorgan failure, in whom the serum concentration of methadone kept increasing despite discontinuation of the drug. Therapeutic drug monitoring was performed to monitor the methadone serum concentration during treatment of the underlying diseases.

Case Report: Polyvinylpyrrolidone deposition disease from repeated injection of opioid substitution drugs: report of a case with a fatal outcome.

Background: Intravenous injection of oral opioid substitution drugs (OSD) is widespread among injecting drug users. Several OSDs contain the polymer polyvinylpyrrolidone (PVP) as an excipient. Parenterally administered PVP of high molecular weight may accumulate in tissues and organs. This phenomenon was first described in the 1950s, when PVP was utilised in medication for parenteral use. We report a case of an opioid-addicted patient with extensive PVP-deposition caused by repeated injections of OSDs. Case presentation: A 30-year-old male drug addicted patient in opioid substitution therapy (OST) was repeatedly referred to his local hospital in a poor general condition. Work-up revealed severe normocytic anaemia, renal insufficiency, pancreas insufficiency and pathological fractures. Biopsies from fractured bones, bone marrow and gastric mucosa showed extensive infiltrates of histiocytes with intracytoplasmic vacuoles. Vacuole content stained slightly bluish in hematoxylin and eosin stain, red in Congo red stain and black in periodic acid methenamine silver stain. The morphological appearance and staining properties were in accordance with the diagnosis of PVP deposition. The patient had been injecting both buprenorphine tablets and a specific methadone syrup for several years. The methadone syrup contained large amounts of high molecular weight PVP, making it the most likely cause of the deposition. His health quickly deteriorated and he died, impaired by multi-organ failure and cachexia, five years after the first diagnosis of PVP-deposition. The autopsy revealed extensive PVP-deposition in all sampled organs and tissues. Conclusions: Histological investigation and the correct identification of PVP in the biopsies led to the discovery of a severe adverse effect from long-standing misuse of a drug. The disseminated PVP deposition likely contributed to multi-organ dysfunction and cachexia with a fatal outcome. The deposited PVP likely originated from repeated injections of a certain methadone syrup.

Polyvinylpyrrolidone deposition disease in patients with intravenous opioid use: a case series.

The polymer polyvinylpyrrolidone (PVP) is an excipient widely used in prescription drugs. Depending on the molecular weight (MW), parenterally administered PVP may accumulate in various tissues. Consequently, moderate and high MW PVP have only been used in oral preparations since the late 1970s. Surprisingly, starting in 2009, pathology departments in Norway received biopsies revealing PVP deposition, all from patients with a history of intravenous drug use. We identified 13 patients with PVP deposition and re-evaluated 31 biopsies and two autopsies. Common indications for biopsy were renal insufficiency, anemia, pathological fractures, and abdominal complaints. We observed PVP deposits in all biopsies (kidney, hematopoietic bone marrow, bone, gastrointestinal tract, lymph node, and skin) and all sampled tissue from the autopsies. Overall, the clinical findings could be related to PVP deposits in the biopsies. In the most seriously affected patients, PVP deposition caused severe organ dysfunction and contributed to the fatal outcomes of two patients. All patients except for one were prescribed opioid substitution drugs (OSDs), and most of the patients admitted to having injected such medications. Several OSDs contain PVP. One methadone formulation that was marketed in Norway from 2007 to 2014 contained large amounts of very high MW PVP, making it the most likely source of PVP deposition. Although the presumed source of PVP in these patients has now been withdrawn from the market, pathologists should be aware of PVP deposits when evaluating biopsies from this patient group.

Perception of prescribing factors and purchase statistics of non-steroidal anti-inflammatory drugs in an orthopedic clinic.

OBJECTIVES: Nonsteroidal anti-inflammatory drugs (NSAIDS) are associated with concern of adverse drug reactions (ADRS) including gastrointestinal, cardiovascular, renal, and musculoskeletal. Non-selective and selective NSAIDS are proposed to differ with regard to their potential to cause ADRS. The aim of this pilot study was to compare perception of prescribing factors and purchase statistics of NSAIDS among physicians in a Norwegian orthopedic clinic. RESULTS: Forty-five (55%) of 82 invited physicians from the orthopedic clinic participated anonymous in a survey in February 2017. Effect and ADRS were rated as the most important factors for prescribing of NSAIDS. The participants were equally concerned about specific ADRS for prescription of non-selective and selective NSAIDS irrespective of type of ADR. They were generally more concerned about cardiovascular, gastrointestinal and renal ADRS than musculoskeletal. Purchase statistics from 2015 and 2016 showed that celecoxib, a selective NSAID, dominated in the orthopedic clinic. The discrepancy between perception of prescribing factors and purchase statistics of NSAIDS was possibly explained by a high degree of conformity to clinic guidelines. Our preliminary results indicate that perception of prescribing factors of NSAIDS among orthopedics should be surveyed in multicenter or multinational studies.

Ultrasound- and Microbubble-Assisted Gemcitabine Delivery to Pancreatic Cancer Cells.

Pancreatic ductal adenocarcinoma (PDAC) is a major cause of cancer death worldwide. Poor drug delivery to tumours is thought to limit chemotherapeutic treatment efficacy. Sonoporation combines ultrasound (US) and microbubbles to increase the permeability of cell membranes. We assessed gemcitabine uptake combined with sonoporation in vitro in three PDAC cell lines (BxPC-3, MIA PaCa-2 and PANC-1). Cells were cultured in hypoxic bioreactors, while gemcitabine incubation ± sonoporation was conducted in cells with operational or inhibited nucleoside membrane transporters. Intracellular active metabolite (dFdCTP), extracellular gemcitabine, and inactive metabolite (dFdU) concentrations were measured with liquid chromatography tandem mass spectrometry. Sonoporation with increasing US intensities resulted in decreasing extracellular gemcitabine concentrations in all three cell lines with inhibited membrane transporters. In cells with inhibited membrane transporters, without sonoporation, dFdCTP concentrations were reduced down to 10% of baseline. Sonoporation partially restored gemcitabine uptake in these cells, as indicated by a moderate increase in dFdCTP concentrations (up to 37% of baseline) in MIA PaCa-2 and PANC-1. In BxPC-3, gemcitabine was effectively inactivated to dFdU, which might represent a protective mechanism against dFdCTP accumulation in these cells. Intracellular dFdCTP concentrations did not change significantly following sonoporation in any of the cell lines with operational membrane transporters, indicating that the gemcitabine activation pathway may have been saturated with the drug. Sonoporation allowed a moderate increase in gemcitabine transmembrane uptake in all three cell lines, but pre-existing nucleoside transporters were the major determinants of gemcitabine uptake and retention.

Intracellular Cytidine Deaminase Regulates Gemcitabine Metabolism in Pancreatic Cancer Cell Lines.

Cytidine deaminase (CDA) is a determinant of in vivo gemcitabine elimination kinetics and cellular toxicity. The impact of CDA activity in pancreatic ductal adenocarcinoma (PDAC) cell lines has not been elucidated. We hypothesized that CDA regulates gemcitabine flux through its inactivation and activation pathways in PDAC cell lines. Three PDAC cell lines (BxPC-3, MIA PaCa-2, and PANC-1) were incubated with 10 or 100 µM gemcitabine for 60 minutes or 24 hours, with or without tetrahydrouridine, a CDA inhibitor. Extracellular inactive gemcitabine metabolite (dFdU) and intracellular active metabolite (dFdCTP) were quantified with liquid chromatography tandem mass spectrometry. Cellular expression of CDA was assessed with real-time PCR and Western blot. Gemcitabine conversion to dFdU was extensive in BxPC-3 and low in MIA PaCa-2 and PANC-1, in accordance with their respective CDA expression levels. CDA inhibition was associated with low or undetectable dFdU in all three cell lines. After 24 hours gemcitabine incubation, dFdCTP was highest in MIA PaCa-2 and lowest in BxPC-3. CDA inhibition resulted in a profound dFdCTP increase in BxPC-3 but not in MIA PaCa-2 or PANC-1. dFdCTP concentrations were not higher after exposure to 100 versus 10 µM gemcitabine when CDA activities were low (MIA PaCa-2 and PANC-1) or inhibited (BxPC-3). The results suggest a regulatory role of CDA for gemcitabine activation in PDAC cells but within limits related to the capacity in the activation pathway in the cell lines. SIGNIFICANCE STATEMENT: The importance of cytidine deaminase (CDA) for cellular gemcitabine toxicity, linking a lower activity to higher toxicity, is well described. An underlying assumption is that CDA, by inactivating gemcitabine, limits the amount available for the intracellular activation pathway. Our study is the first to illustrate this regulatory role of CDA in pancreatic ductal adenocarcinoma cell lines by quantifying intracellular and extracellular gemcitabine metabolite concentrations.

A human clinical trial using ultrasound and microbubbles to enhance gemcitabine treatment of inoperable pancreatic cancer.

BACKGROUND: The primary aim of our study was to evaluate the safety and potential toxicity of gemcitabine combined with microbubbles under sonication in inoperable pancreatic cancer patients. The secondary aim was to evaluate a novel image-guided microbubble-based therapy, based on commercially available technology, towards improving chemotherapeutic efficacy, preserving patient performance status, and prolonging survival. METHODS: Ten patients were enrolled and treated in this Phase I clinical trial. Gemcitabine was infused intravenously over 30min. Subsequently, patients were treated using a commercial clinical ultrasound scanner for 31.5min. SonoVue® was injected intravenously (0.5ml followed by 5ml saline every 3.5min) during the ultrasound treatment with the aim of inducing sonoporation, thus enhancing therapeutic efficacy. RESULTS: The combined therapeutic regimen did not induce any additional toxicity or increased frequency of side effects when compared to gemcitabine chemotherapy alone (historical controls). Combination treated patients (n=10) tolerated an increased number of gemcitabine cycles compared with historical controls (n=63 patients; average of 8.3±6.0cycles, versus 13.8±5.6cycles, p=0.008, unpaired t-test). In five patients, the maximum tumour diameter was decreased from the first to last treatment. The median survival in our patients (n=10) was also increased from 8.9months to 17.6months (p=0.011). CONCLUSIONS: It is possible to combine ultrasound, microbubbles, and chemotherapy in a clinical setting using commercially available equipment with no additional toxicities. This combined treatment may improve the clinical efficacy of gemcitabine, prolong the quality of life, and extend survival in patients with pancreatic ductal adenocarcinoma.

Pharmacology Portal: An Open Database for Clinical Pharmacologic Laboratory Services.

PURPOSE: More than 50 Norwegian public and private laboratories provide one or more analyses for therapeutic drug monitoring or testing for drugs of abuse. Practices differ among laboratories, and analytical repertoires can change rapidly as new substances become available for analysis. METHODS: The Pharmacology Portal was developed to provide an overview of these activities and to standardize the practices and terminology among laboratories. The Pharmacology Portal is a modern dynamic web database comprising all available analyses within therapeutic drug monitoring and testing for drugs of abuse in Norway. Content can be retrieved by using the search engine or by scrolling through substance lists. The core content is a substance registry updated by a national editorial board of experts within the field of clinical pharmacology. This ensures quality and consistency regarding substance terminologies and classification. FINDINGS: All laboratories publish their own repertoires in a user-friendly workflow, adding laboratory-specific details to the core information in the substance registry. The user management system ensures that laboratories are restricted from editing content in the database core or in repertoires within other laboratory subpages. The portal is for nonprofit use, and has been fully funded by the Norwegian Medical Association, the Norwegian Society of Clinical Pharmacology, and the 8 largest pharmacologic institutions in Norway. IMPLICATIONS: The database server runs an open-source content management system that ensures flexibility with respect to further development projects, including the potential expansion of the Pharmacology Portal to other countries.

Preanalytical Stability of Gemcitabine and its Metabolite 2', 2'-Difluoro-2'-Deoxyuridine in Whole Blood-Assessed by Liquid Chromatography Tandem Mass Spectrometry.

Gemcitabine (2',2'-difluoro-2'-deoxycytidine, dFdC) and metabolite (2',2'-difluoro-2'-deoxyuridine, dFdU) quantification is warranted for individualized treatment strategies. Analyte stability is crucial for the validity of such quantification. We therefore studied the impact of the time interval from blood sampling to separation of plasma on gemcitabine stability. Blood from gemcitabine-treated patients was drawn into tetrahydrouridine (THU)-spiked heparin and ethylenediaminetetraacetic acid tubes and kept on ice until separation. Plasma was separated sequentially up to 24 h after sampling and dFdC and dFdU were quantified by liquid chromatography tandem mass spectrometry (LC-MS/MS). The change in plasma concentrations over time was compared with the highest imprecision for concentrations above the lower limit of quantification of the LC-MS/MS method. Analyte concentrations decreased slightly over time, but for samples stored for 4 h on ice, the decline was smaller than the expected analytical imprecision. After 24 h, the maximum decline was 14.0%, which exceeded the expected analytical imprecision. dFdC and dFdU stabilities were acceptable for at least 4 h when THU-spiked whole blood samples were kept on ice. This is within the scope of routine sampling procedures. Further, variations in separation time intervals within this time frame are negligible when interpreting drug concentrations.

Liquid chromatography/tandem mass spectrometry method for simultaneous quantification of eight endogenous nucleotides and the intracellular gemcitabine metabolite dFdCTP in human peripheral blood mononuclear cells.

Quantification of endogenous nucleotides is of interest for investigation of numerous cellular biochemical processes, such as energy metabolism and signal transduction, and may also be applied in cancer and antiretroviral therapies in which nucleoside analogues are used. For these purposes we developed and validated a sensitive and high accuracy ion-pair liquid chromatography tandem mass spectrometry (IP LC-MS/MS) method for simultaneous quantification of eight endogenous nucleotides (ATP, CTP, GTP, UTP, dATP, dCTP, dGTP, dTTP) and 2',2'-difluoro-2'-deoxycytidine triphosphate (dFdCTP), an intracellular metabolite of the nucleoside analogue gemcitabine. The assay was validated using 200µL aliquots of peripheral blood mononuclear cell (20×10(6)cells/ml, 4×10(6)cells) extracts, pretreated with activated charcoal and spiked with unlabeled nucleotides, deoxynucleotides and dFdCTP. Analytes were extracted by simple precipitation with cold 60% methanol containing isotope labeled internal standards and separated on a porous graphitic carbon column. For method validation, the concentration ranges were: 0.125-20.8pmol injected for deoxynucleotides, 0.25-312.5pmol injected for dFdCTP and 5-3200pmol injected for nucleotides. The highest coefficients of variation (CV) were 12.1% for within run assay and 11.4% for between run assay, both representing the precision at the lowest analyte concentrations. The method was applied to monitor dFdCTP and changes in endogenous nucleotides in patients who were receiving gemcitabine infusions.