RUNX1 Mutations in the Leukemic Progression of Severe Congenital Neutropenia

Somatic RUNX1 mutations are found in approximately 10% of patients with de novo acute myeloid leukemia (AML), but are more common in secondary forms of myelodysplastic syndrome (MDS) or AML. Particularly, this applies to MDS/AML developing from certain types of leukemia-prone inherited bone marrow failure syndromes. How these RUNX1 mutations contribute to the pathobiology of secondary MDS/AML is still unknown. This mini-review focusses on the role of RUNX1 mutations as the most common secondary leukemogenic hit in MDS/AML evolving from severe congenital neutropenia (SCN)

Pharmacokinetic/pharmacodynamic analysis of weight- and height-scaled tobramycin dosage regimens for patients with cystic fibrosis

OBJECTIVES: To determine the outcomes of weight- and height-based tobramycin dosing regimens for patients with cystic fibrosis (CF). METHODS: A simulated dataset of 5000 patients based on 331 patients with CF was created using NONMEM. Pharmacokinetic (PK) parameters were derived for each patient from a published model using Monte Carlo simulation. The abilities of 10 and 12 mg/kg/day and 3 and 4 mg/cm/day to achieve standard and extended Cmax (20-30 and 20-40 mg/L) and AUC0-24 (80-120 and 80-150 mg·h/L) targets were evaluated. PK/pharmacodynamic (PK/PD) indices were a Cmax/MIC ratio ≥10 and an AUC0-24/MIC ratio ≥110. For these indices and a range of MICs, cumulative fractions of response (CFRs) for Pseudomonas aeruginosa were also determined. RESULTS: More patients achieved standard Cmax and AUC0-24 targets with 3 mg/cm/day (64% and 62%, respectively) than with 10 mg/kg/day (43% and 48%, respectively). AUC0-24 estimates >120 mg·h/L were more common with weight-based dosing. With higher doses, 72% achieved high target peaks with 4 mg/cm/day and 65% with 12 mg/kg/day. For the Cmax/MIC index, the maximal MIC for the target microorganism was 2 mg/L with lower doses, 2.5 mg/L with higher doses and 0.5 mg/L for AUC0-24/MIC-based regimens. The CFR for all regimens was >90% for Cmax targets and 66% to 79% for AUC0-24 targets. CONCLUSIONS: A tobramycin dose of 3 mg/cm/day rather than 10 mg/kg/day achieved similar PK/PD outcomes but dose and AUC0-24 ranges were narrower and the incidence of high AUC0-24 values was lower. Height-based doses should therefore be considered for patients with CF

The potential impact of CT-MRI matching on tumor volume delineation in advanced head and neck cancer

To study the potential impact of the combined use of CT and MRI scans on the Gross Tumor Volume (GTV) estimation and interobserver variation. Four observers outlined the GTV in six patients with advanced head and neck cancer on CT, axial MRI, and coronal or sagittal MRI. The MRI scans were subsequently matched to the CT scan. The interobserver and interscan set variation were assessed in three dimensions. The mean CT derived volume was a factor of 1.3 larger than the mean axial MRI volume. The range in volumes was larger for the CT than for the axial MRI volumes in five of the six cases. The ratio of the scan set common (i.e., the volume common to all GTVs) and the scan set encompassing volume (i.e., the smallest volume encompassing all GTVs) was closer to one in MRI (0.3-0.6) than in CT (0.1-0.5). The rest volumes (i.e., the volume defined by one observer as GTV in one data set but not in the other data set) were never zero for CT vs. MRI nor for MRI vs. CT. In two cases the craniocaudal border was poorly recognized on the axial MRI but could be delineated with a good agreement between the observers in the coronal/sagittal MRI. MRI-derived GTVs are smaller and have less interobserver variation than CT-derived GTVs. CT and MRI are complementary in delineating the GTV. A coronal or sagittal MRI adds to a better GTV definition in the craniocaudal directio

Dried blood spot analysis:facing new challenges

Over the last decade, DBS analysis has gained popularity for TDM because it’s a patient friendly sampling proce- dure [1-4]. Additional advantages are prolonged sample stability, lower risk of infections and transportation at ambient temperature [1-3,5]. These advantages may fa- cilitate implementation of TDM in different clinical set- tings including resource limited areas. Patients will bene- fit from DBS analysis but the analytical development and validation of DBS methods is more complex compared to plasma or serum analysis. Additional validation parameters, like the effect of the hematocrit (HT) and blood spot volume need to be eval- uated. Drug substances may also interact with the blood matrix or with the DBS card, resulting in matrix related recovery effects. Unfortunately, official guidelines for val- idation of DBS are not available yet. However, in recent literature, several interesting issues related to analytical DBS research have been discussed [1,6-12]. Ongoing re- search and improved understanding of the factors that influence DBS analysis results will ultimately result in well-founded guidelines for DBS analytical method val- idation. This would be very helpful for daily practice but would also benefit patient safety because uniformity in method validation prevents potential pitfalls during val- idation or method development and increase credibility of assay results. Our aim is to discuss some relevant topics related to DBS development prior to development of future guidelines on DBS development and validation

Reducing the risk of non-sterility of aseptic handling in hospital pharmacies, part A:Risk assessment

OBJECTIVES: To determine prospectively the sources of risk of non-sterility during aseptic handling and to quantify the risks of each of these sources. METHODS: A risk assessment (RA) of non-sterility according to Failure Mode and Effect Analysis was executed by a multidisciplinary team of (hospital) pharmacists and technicians, a consultant experienced in aseptic processing and an independent facilitator. The team determined the sources of risk of non-sterility, a 5 point scale for severity, occurrence and detection, and risk acceptance levels. Input about general applied risk reduction was collected by audits in 10 hospital pharmacies. The results of these audits were used for determining the remaining risks. The results, as well as scientific information and the experience of the team members, was used to determine scores for severity, occurrence and detection. RESULTS: Multiplying the scores for severity, occurrence and detection results in the risk prioritisation number (RPN) which is a relative value of the remaining risks of non-sterility for each source. Incorrect disinfection techniques of non-sterile materials and the chances of touching critical spots were estimated as the greatest risks. The risk of non-sterility via the airborne route was low. RPN values were helpful in prioritising measures for additional risk reduction (this will be described in an accompanying article). CONCLUSION: The RA, described here, was a systematic survey related to all sources of risk of non-sterility during aseptic handling. The determined RPN values were helpful in prioritising measures for additional risk reduction

Reducing the risk of non-sterility of aseptic handling in hospital pharmacies, part C:Applying risk assessment and risk control in practice

OBJECTIVES: To describe the application of the model described in part A and part B of this series of articles for risk assessment (RA) and risk control (RC) of non-sterility during aseptic handling. The model was applied in nine hospital pharmacies.METHODS: The starting point was an audit of each hospital pharmacy. The determined risk reduction and remaining risks were entered into a risk assessment model. The corresponding risk prioritisation numbers (RPNs) for each source of risk were calculated and these values were summed up to a cumulative RPN. Subsequently, all hospital pharmacies started an improvement programme, using the risk assessment as input. Results of aseptic process simulation (APS) and microbiological monitoring (MM) were also collected. The participants were informed about their progress of risk reduction and results of APS and MM during the study period. At the end of the study (about 4 years after the start), a final assessment was executed by using a checklist with risk reducing measures for each source of risk. Additional risk reduction and remaining risks were put in an RA and RC template and corresponding RPN values and a new cumulative RPN were determined.RESULTS: At the start of the study differences in cumulative RPN values were relatively small (from 630 to 825). At the end they were relatively great (from 230 to 725), which illustrates a different sense of urgency for reducing the risk of non-sterility. Of all the risk reducing measures, a yearly audit of all operators had the greatest impact on reducing the risk of non-sterility. Except for glove prints, there was no correlation between process improvement (lower cumulative RPN) and results of microbiological controls.CONCLUSION: A systematic and science-based reduction of the risks of non-sterility can be done by using a checklist with risk reducing measures and an RA &amp; RC template. Prospectively, the relevance of each risk reducing measure can be demonstrated by RPN calculations. Microbiological controls are an important part of the overall assurance of product quality. However, the results are less useful for assessing the risk of non-sterility.</p

Simple, fast and robust LC-MS/MS method for the simultaneous quantification of canagliflozin, dapagliflozin and empagliflozin in human plasma and urine

Sodium–glucose cotransporter 2 –inhibitors (SGLT2i) are oral glucose-lowering drugs that have also demonstrated cardioprotective and renoprotective effects. SGLT2i play an increasingly important role in the treatment of type 2 diabetes. Here we report a simple and robust liquid chromatography–tandem mass spectrometry (LC–MS/MS) method for the simultaneous quantification of three SGLT2i (canagliflozin, dapagliflozin and empagliflozin) in human plasma, serum and urine with a runtime of 1 min. Methanol was used as protein precipitating agent. Chromatographic separation was accomplished using a Waters ACQUITY UPLC HSS T3 1.8 μm; 2.1 × 50 mm column with a Waters ACQUITY UPLC HSS T3 1.8 μm VanGuard Pre-column; 2.1 × 5 mm, using gradient elution with ammonium acetate 20 mM (pH 5) and acetonitrile as mobile phase at a flow rate of 0.8 ml/min. Mass spectrometric analysis of the acetate adduct ions was carried out using electrospray with negative ionization and SRM mode. The assay was validated according to FDA and EMA guidelines, including selectivity, linearity, accuracy and precision, dilution integrity, stability and recovery. With a sample volume of 200 µl, linear ranges of 10–5000 µg/L, 1–500 µg/L and 2–1000 µg/L for canagliflozin, dapagliflozin and empagliflozin respectively, were achieved. The assay was successfully applied in two pharmacokinetic studies with dapagliflozin and empagliflozin. In conclusion, we developed and validated a simple, fast and robust LC-MS/MS method for the simultaneous quantification of canagliflozin, dapagliflozin and empagliflozin, that allows rapid analysis of large numbers of samples and can be used for both pharmacokinetic studies and biomedical analysis of canagliflozin, dapagliflozin and empagliflozin

Volumetric absorptive microsampling and dried blood spot microsampling vs. conventional venous sampling for tacrolimus trough concentration monitoring

Objectives: Monitoring tacrolimus blood concentrations is important for preventing allograft rejection in transplant patients. Our hospital offers dried blood spot (DBS) sampling, giving patients the opportunity to sample a drop of blood from a fingerprick at home, which can be sent to the laboratory by mail. In this study, both a volumetric absorptive microsampling (VAMS) device and DBS sampling were compared to venous whole blood (WB) sampling. Methods: A total of 130 matched fingerprick VAMS, fingerprick DBS and venous WB samples were obtained from 107 different kidney transplant patients by trained phlebotomists for method comparison using Passing-Bablok regression. Bias was assessed using Bland-Altman. A multidisciplinary team pre-defined an acceptance limit requiring ï80% of all matched samples within 15% of the mean of both samples. Sampling quality was evaluated for both VAMS and DBS samples. Results: 32.3% of the VAMS samples and 6.2% of the DBS samples were of insufficient quality, leading to 88 matched samples fit for analysis. Passing-Bablok regression showed a significant difference between VAMS and WB, with a slope of 0.88 (95% CI 0.81-0.97) but not for DBS (slope 1.00; 95% CI 0.95-1.04). Both VAMS (after correction for the slope) and DBS showed no significant bias in Bland-Altman analysis. For VAMS and DBS, the acceptance limit was met for 83.0% and 96.6% of the samples, respectively. Conclusions: VAMS sampling can replace WB sampling for tacrolimus trough concentration monitoring, but VAMS sampling is currently inferior to DBS sampling, both regarding sample quality and agreement with WB tacrolimus concentrations. c 2020 Daan J. Touw et al., published by De Gruyter

Improving the aseptic transfer procedures in hospital pharmacies. Part B:evaluation of disinfection methods for materials with a non-sterile surface

Objectives To improve the disinfection methods for materials with a non-sterile surface to be used in aseptic handling. Methods The surface bioburden on ampoules (A) and injection vials (IV) is determined by contact plates and total immersion. The occurrence of spore-forming bacteria is determined by strain colouring and matrix-assisted laser desorption ionisation-time of flight mass spectrometry. The disinfection procedures of non-sterile materials in 10 hospital pharmacies are judged by observing. Results After wiping according to local disinfection methods, the mean surface bioburden determined by contact plates in 10 hospital pharmacies is 0.36 (plastic A), 0.50 (glass A) and 0.29 colony-forming unit (cfu) (IV). The observers found great differences in accuracy of wiping and degree of wetting the sterile gauzes. After improved wiping with commercially available alcohol impregnated sterile wipes and a two-towel technique (one-step TT disinfection), the mean surface bioburden determined by contact plates is 0.03 (plastic A), 0.2 (glass A) and 0.13 cfu (IV). Further improvement can be reached by submerging A and IV in ethanol 70% followed by improved wiping (two-step TT disinfection), but still micro-organisms will remain (mean surface bioburden determined by total immersion is 0 (plastic A) and 0.3 cfu (IV); glass A not determined). Two-step TT disinfection is more labour intensive. Spilling of alcohol is another disadvantage. However, we presume one-step TT disinfection is effective enough in daily practice. Routine surface bioburden determinations have to prove this. The effectiveness of the combination of spray and wipe is not examined because we observed a quick disappearance of alcohols from vertical as well as horizontal surfaces, which shortens the contact time to far below the advised 2 min. Spore-forming bacteria disappear as quickly as other micro-organisms during disinfection by alcohols. Conclusion Local disinfection procedures can be improved. Complete removal of micro-organisms from materials with a non-sterile surface, even after two-step TT disinfection, is impossible. Routine surface bioburden determinations have to prove if one-step TT disinfection is effective enough