Population pharmacokinetics of treosulfan in paediatric patients undergoing hematopoietic stem cell transplantation

Aims: Treosulfan is an alkylating agent increasingly used prior to haematopoietic stem cell transplantation. The aim of this study was to develop a population pharmacokinetic (PK) model of treosulfan in paediatric haematopoietic stem cell transplantation recipients and to explore the effect of potential covariates on treosulfan PK. Also, a limited sampling model (LSM) will be developed to accurately predict treosulfan exposure suitable for a therapeutic drug monitoring setting. Methods: In this multicentre study, 91 patients, receiving a total dose of 30, 36 or 42 g/m2 treosulfan, administered over 3 consecutive days, were enrolled. A population PK model was developed and demographic factors, as well as laboratory parameters, were included as potential covariates. In addition, a LSM was developed using data from 28 patients. Results: A 2-compartment model with first order elimination best described the data. Bodyweight with allometric scaling and maturation function were identified as significant predictors of treosulfan clearance. Treosulfan clearance reaches 90% of adult values at 4 postnatal years. A model-based dosing table is presented to target an exposure of 1650 mg*h/L (population median) for different weight and age groups. Samples taken at 1.5, 4 and 7 hours after start of infusion resulted in the best limited sampling strategy. Conclusions: This study provides a treosulfan population PK model in children and captures the developmental changes in clearance. A 3-point LSM allows for accurate and precise estimation of treosulfan exposure

High interpatient variability of treosulfan exposure is associated with early toxicity in paediatric HSCT: a prospective multicentre study

Treosulfan-based conditioning is increasingly employed in paediatric haematopoietic stem cell transplantation (HSCT). Data on treosulfan pharmacokinetics in children are scarce, and the relationship between treosulfan exposure, toxicity and clinical outcome is unresolved. In this multicentre prospective observational study, we studied treosulfan pharmacokinetics and the drug's relationship with regimen-related toxicity and early clinical outcome in 77 paediatric patients. Treosulfan dose was 30 g/m2, administered over 3 consecutive days in infants <1 year old (n = 12) and 42 g/m2 in children ≥1 year old (n = 65). Mean day 1 treosulfan exposure was 1744 ± 795 mg*h/l (10 g/m2) and 1561 ± 511 mg*h/l (14 g/m2), with an inter-individual variability of 56 and 33% in the respective groups. High treosulfan exposure (>1650 mg*h/l) was associated with an increased risk of mucosal [Odds ratio (OR) 4·40; 95% confidence interval (CI) 1·19–16·28, P = 0·026] and skin toxicity (OR 4·51; 95% CI 1·07–18·93, P = 0·040). No correlation was found between treosulfan exposure and the early clinical outcome parameters: engraftment, acute graft-versus-host disease and donor chimerism. Our study provides the first evidence in a large cohort of paediatric patients of high variability in treosulfan pharmacokinetics and an association between treosulfan exposure and early toxicity. Ongoing studies will reveal whether treosulfan exposure is related to long-term disease-specific outcome and late treatment-related toxicity

Quality of life after esophageal replacement in children

Purpose: Assessing quality of life (QoL) after esophageal replacement (ER) for long gap esophageal atresia (LGEA). Methods: All patients after ER for LGEA with gastric pull-up (GPU n = 9) or jejunum interposition (JI n = 14) at the University Medical Center Groningen and Utrecht (1985–2007) were included. QoL was assessed with 1) gastrointestinal-related QoL using the Gastrointestinal Quality of Life Index (GIQLI)), 2) general QoL (Child Health questionnaire CHF87-BREF (children)/World Health Organization questionnaire WHOQOL-BREF (adults)), and 3) health-related QoL (HRQoL) (TNO AZL TACQoL/TAAQoL). Association of morbidity (heartburn, dysphagia, dyspnea on exertion, recurrent cough) and (HR)QoL was evaluated. Results: Six patients after GPU (75%) and eight patients after JI (57%) responded to the questionnaires (mean age 15.7, SD 5.9, 12 male, two female). Mean gastrointestinal, general and health-related QoL total scores of the patients were comparable to healthy controls. However, young adults reported a worse physical functioning (p = 0.02) but better social functioning compared to peers (p = 0.01). Morbidity was not associated with significant differences in (HR)QoL. Conclusions: With the current validated QoL most patients after ER with GPU and JI for LGEA have normal generic and disease specific QoL scores. Postoperative morbidity does not seem to influence (HR)QoL. Type of Study: Prognosis Study. Level of evidence: III

High Treosulfan Exposure is Associated with Early Toxicity in Pediatric Hematopoietic Stem Cell Transplantation: A Prospective Multicenter Study

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Effectiveness and toxicity of lenvatinib in refractory thyroid cancer:Dutch real-life data

Objective: The SELECT trial showed progression-free survival (PFS) benefit for lenvatinib for advanced radioiodine-refractory differentiated thyroid cancer (RAI-refractory or RR-DTC) patients, on which current clinical practice is based. We assessed whether the effectiveness and toxicity of lenvatinib in real-life clinical practice in the Netherlands were comparable to the pivotal SELECT trial. Methods: From three Dutch centres Electronic Health Records (EHRs) of patients treated in the lenvatinib compassionate use program or as standard of care were reviewed and checked for SELECT eligibility criteria. Baseline characteristics, safety, and efficacy measures were compared and PFS and overall survival (OS) were calculated. Furthermore, PFS was compared to estimates of PFS reported in other studies. Results: A total of 39 DTC patients with a median age of 62 years were analysed. Of these, 27 patients (69%) did not fulfil the SELECT eligibility criteria. The most common grade >= 3 toxicities were hypertension (n = 11, 28%), diarrhoea (n = 7, 18%), vomiting (n = 4, 10%), and gallbladder disease (n = 3, 8%). Median PFS and median OS were 9.7 (95% confidence interval (CI): 4.0-15.5) and 18.3 (95% CI: 4.9-31.7) months, respectively, response rate was 38% (95% CI: 23-54%). PFS in the Dutch real-life situation was comparable to previous real-life studies, but inferior to PFS as shown in the SELECT trial (P = 0.04). Conclusions: PFS in our non-trial population was significantly shorter than in the SELECT trial population. In the interpretation of results, differences in the real-life population and the SELECT study population regarding patient characteristics should be taken into account

Influence of pharmacogenetic variability on the pharmacokinetics and toxicity of the aurora kinase inhibitor danusertib

Objectives Danusertib is a serine/threonine kinase inhibitor of multiple kinases, including aurora-A, B, and C. This explorative study aims to identify possible relationships between single nucleotide polymorphisms in genes coding for drug metabolizing enzymes and transporter proteins and clearance of danusertib, to clarify the interpatient variability in exposure. In addition, this study explores the relationship between target receptor polymorphisms and toxicity of danusertib. Methods For associations with clearance, 48 cancer patients treated in a phase I study were analyzed for ABCB1, ABCG2 and FMO3 polymorphisms. Association analyses between neutropenia and drug target receptors, including KDR, RET, FLT3, FLT4, AURKB and AURKA, were performed in 30 patients treated at recommended phase II dose-levels in three danusertib phase I or phase II trials. Results No relationships between danusertib clearance and drug metabolizing enzymes and transporter protein polymorphisms were found. Only, for the one patient with FMO3 18281AA polymorphism, a significantly higher clearance was noticed, compared to patients carrying at least 1 wild type allele. No effect of target receptor genotypes or haplotypes on neutropenia was observed. Conclusions As we did not find any major correlations between pharmacogenetic variability in the studied enzymes and transporters and pharmacokinetics nor toxicity, it is unlikely that danusertib is highly susceptible for pharmacogenetic variation. Therefore, no dosing alterations of danusertib are expected in the future, based on the polymorphisms studied. However, the relationship between FMO3 polymorphisms and clearance of danusertib warrants further research, as we could study only a small group of patients

Liver and kidney function in patients with Covid-19 treated with remdesivir

For the treatment of Covid-19 patients with remdesivir, poor renal and liver function were both exclusion criteria in randomized clinical trials and contraindication for treatment. Also, nephrotoxicity and hepatotoxicity are reported as adverse events. We retrospectively reviewed renal and liver functions of Covid-19 103 patients who received remdesivir in the 15 days after treatment initiation. Approximately 20% of the patient population met randomized clinical trial exclusion criteria. In total, 11% of the patients had a decrease in estimated glomerular filtration rate >10 mL/min/1.73m(2). Also, 25 and 35% had increased alanine transaminase and aspartate transaminase levels, respectively. However, serious adverse events were limited. Therefore, based on these preliminary results, contraindications based on kidney and liver function should not be absolute for remdesivir treatment in patients with Covid-19 if these functions are monitored regularly. A larger patient cohort is warranted to confirm our results.Immunogenetics and cellular immunology of bacterial infectious disease

Treosulfan-induced myalgia in pediatric hematopoietic stem cell transplantation identified by an electronic health record text mining tool

Treosulfan is increasingly used as myeloablative agent in conditioning regimen prior to allogeneic hematopoietic stem cell transplantation (HSCT). In our pediatric HSCT program, myalgia was regularly observed after treosulfan-based conditioning, which is a relatively unknown side effect. Using a natural language processing and text-mining tool (CDC), we investigated whether treosulfan compared with busulfan was associated with an increased risk of myalgia. Furthermore, among treosulfan users, we studied the characteristics of given treatment of myalgia, and studied prognostic factors for developing myalgia during treosulfan use. Electronic Health Records (EHRs) until 28 days after HSCT were screened using the CDC for myalgia and 22 synonyms. Time to myalgia, location of pain, duration, severity and drug treatment were collected. Pain severity was classified according to the WHO pain relief ladder. Logistic regression was performed to assess prognostic factors. 114 patients received treosulfan and 92 busulfan. Myalgia was reported in 37 patients; 34 patients in the treosulfan group and 3 patients in the busulfan group (p = 0.01). In the treosulfan group, median time to myalgia was 7 days (0-12) and median duration of pain was 19 days (4-73). 44% of patients needed strong acting opiates and adjuvant medicines (e.g. ketamine). Hemoglobinopathy was a significant risk factor, as compared to other underlying diseases (OR 7.16 95% CI 2.09-30.03, p = 0.003). Myalgia appears to be a common adverse effect of treosulfan in pediatric HSCT, especially in hemoglobinopathy. Using the CDC, EHRs were easily screened to detect this previously unknown side effect, proving the effectiveness of the tool. Recognition of treosulfan-induced myalgia is important for adequate pain management strategies and thereby for improving the quality of hospital stay.Clinical Pharmacy and Toxicolog

Real-world metastatic renal cell carcinoma treatment patterns and clinical outcomes in the Netherlands

The number of treatment options for patients with metastatic renal cell carcinoma (mRCC) has significantly grown in the last 15 years. Although randomized controlled trials are fundamental in investigating mRCC treatment efficacy, their external validity can be limited. Therefore, the efficacy of the different treatment options should also be evaluated in clinical practice. We performed a chart review of electronic health records using text mining software to study the current treatment patterns and outcomes. mRCC patients from two large hospitals in the Netherlands, starting treatment between January 2015 and May 2020, were included. Data were collected from electronic health records using a validated text mining tool. Primary endpoints were progression-free survival (PFS) and overall survival (OS). Statistical analyses were performed using the Kaplan-Meier method. Most frequent first-line treatments were pazopanib (n = 70), sunitinib (n = 34), and nivolumab with ipilimumab (n = 28). The overall median PFS values for first-line treatment were 15.7 months (95% confidence interval [95%CI], 8.8-20.7), 16.3 months (95%CI, 9.3-not estimable [NE]) for pazopanib, and 6.9 months (95% CI, 4.4-NE) for sunitinib. The overall median OS values were 33.4 months (95%CI, 28.1-50.9 months), 39.3 months (95%CI, 29.5-NE) for pazopanib, and 28.1 months (95%CI, 7.0-NE) for sunitinib. For nivolumab with ipilimumab, median PFS and median OS were not reached. Of the patients who finished first- and second-line treatments, 64 and 62% received follow-up treatments, respectively. With most patients starting on pazopanib and sunitinib, these real-world treatment outcomes were most likely better than in pivotal trials, which may be due to extensive follow-up treatments.Clinical epidemiolog

PIN71 QUALITY OF LIFE (QOL) AND OTHER ENDPOINTS COMPARISON IN THE TREATMENT OF FACIAL LIPOATROPHY WITH INJECTION OF POLY-L-LACTIC ACID

Context: Longitudinal data on bone mineral density(BMD) in children and adolescents with Prader-Willi Syndrome (PWS) during long-term GH treatment are not available. Objective: This study aimed to determine effects of long-term GH treatment and puberty on BMD of total body (BMDTB), lumbar spine (BMDLS), and bone mineral apparent density of the lumbar spine (BMAD(LS)) in children with PWS. Design and Setting: This was a prospective longitudinal study of a Dutch PWS cohort. Participants: Seventy-seven children with PWS who remained prepubertal during GH treatment for 4 years and 64 children with PWS who received GH treatment for 9 years participated in the study. Intervention: The children received GH treatment, 1 mg/m(2)/day (congruent to 0.035 mg/kg/d). Main Outcome Measures: BMDTB, BMDLS, and BMAD(LS) was measured by using the same dual-energy x-ray absorptiometry machine for all annual measurements. Results: In the prepubertal group, BMDTB standard deviation score (SDS) and BMDLSSDS significantly increased during 4 years of GH treatment whereas BMAD(LS)SDS remained stable. During adolescence, BMDTBSDS and BMAD(LS)SDS decreased significantly, in girls from the age of 11 years and in boys from the ages of 14 and 16 years, respectively, but all BMD parameters remained within the normal range. Higher Tanner stages tended to be associated with lower BMDTBSDS (P = .083) and a significantly lowerBMAD(LS)SDS (P = .016). After 9 years of GH treatment, lean body mass SDS was the most powerful predictor of BMDTBSDS and BMDLSSDS in adolescents with PWS. Conclusions: This long-term GH study demonstrates that BMDTB, BMDLS, and BMAD(LS) remain stable in prepubertal children with PWS but decreases during adolescence, parallel to incomplete pubertal development. Based on our findings, clinicians should start sex hormone therapy from the age of 11 years in girls and 14 years in boys unless there is a normal progression of puberty