Risk assessment of drug interaction potential and concomitant dosing pattern on targeted toxicities in pediatric cancer patients

A Narrative Review of Pain in Pediatric Oncology: The Opioid Option

Opioid therapy is the mainstay for managing pain in pediatric oncology. This narrative review describes the current literature regarding opioids for pediatric cancer pain. The review explores the multifaceted landscape of opioid utilization in this population, including the role of opioids in certain clinical circumstances, modalities of opioid delivery, unique opioids, outpatient and at-home pain management strategies, and other key concepts such as breakthrough pain. This review highlights the importance of individualized dosing and multimodal approaches to enhance efficacy and minimize adverse effects. Drawing from a wide range of evidence, this review offers insights to optimize pediatric oncology pain management.

Potential drug-drug interaction and its determinants among patients with cancer receiving chemotherapy in oncology centres of Northwest Ethiopia: an institutional-based cross-sectional study

OBJECTIVE

The study was conducted to assess potential drug-drug interactions (PDDIs) and its determinants among patients with cancer receiving chemotherapy.

DESIGN AND SETTING

An institutional-based cross-sectional study was used. This study was conducted from 1 June 2021 to 15 December 2021, in Northwest Ethiopia oncology centres.

PARTICIPANTS

All eligible patients with cancer received a combination of chemotherapy.

OUTCOMES

The prevalence and severity of PDDIs were evaluated using three drug interaction databases. Characteristics of participants were presented, arranged and summarised using descriptive statistics. The predictors and outcome variables were examined using logistic regression. The cut-off point was a p value of 0.05.

RESULTS

Of 422 patients included in the study, 304 patients were exposed to at least one PDDI with a prevalence of 72.1% (95 % CI: 68% to 76%) using three drug interaction databases. There were varied reports of the severity of PDDI among databases, but the test agreement using the kappa index was 0.57 (95% CI: 0.52 to 0.62, p=0.0001) which is interpreted as a moderate agreement among three databases. Patients aged ≥50 years old had the risk to be exposed to PDDI by odds of 3.1 times (adjusted OR (AOR)=3.1, 95% CI (1.8 to 5.3); p=0.001) as compared with patients <50 years old. Similarly, patients with polypharmacy and comorbidity were more likely to be exposed to PDDI than their counterparts (AOR=2.4, 95% CI (1.4 to 4.1); p=0.002 and AOR=1.9, 95% CI (1.1 to 3.4); p=0.02, respectively).

CONCLUSION

The main finding of this study is the high prevalence of PDDI, signifying the need for strict patient monitoring for PDDIs among patients with cancer receiving chemotherapy. We suggest the use of at least three drug databases for quality screening. Patients with an age ≥50 years old, polypharmacy and comorbidity were significantly associated with PDDIs. The establishment of oncology clinical pharmacists and computerised reminder mechanisms for PDDIs through drug utilisation review is suggested.

Adverse Drug Reactions in Pediatric Oncohematology: A Systematic Review

Introduction: Adverse drug reactions (ADR) are an important cause of morbidity and mortality in pediatric patients. Due to the disease severity and chemotherapy safety profile, oncologic patients are at higher risk of ADR. However, there is little evidence on pharmacovigilance studies evaluating drug safety in this specific population.

Methods: In order to assess the incidence and characteristics of ADR in pediatric patients with oncohematogical diseases and the methodology used in the studies, a systematic review was carried out using both free search and a combination of MeSH terms. Data extraction and critical appraisal were performed independently using a predefined form.

Results: Fourteen studies were included, of which eight were prospective and half focused in inpatients. Sample size and study duration varied widely. Different methods of ADR identification were detected, used alone or combined. Causality and severity were assessed frequently, whereas preventability was lacking in most studies. ADR incidence varied between 14.4 and 67% in inpatients, and 19.6–68.1% in admissions, mainly in the form of hematological, gastrointestinal and skin toxicity. Between 11 and 16.4% ADR were considered severe, and preventability ranged from 0 to 74.5%.

Conclusion: ADR in oncohematology pediatric patients are frequent. A high variability in study design and results has been found. The use of methodological standards and preventability assessment should be reinforced in order to allow results comparison between studies and centers, and to detected areas of improvement.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=96513, identifier CRD42018096513.

Adverse Reactions to Drugs of Special Interest in a Pediatric Oncohematology Service

Introduction: Drugs used in oncological diseases are frequently related to adverse drug reactions (ADR). Few studies have analyzed the toxicity of cancer treatments in children in real practice.

Methods: An observational, longitudinal and prospective study has been carried out in an Oncohematology Service of a tertiary hospital. During 2017, patients exposed to one or more drugs of a previously agreed list were identified and followed-up for at least 6 months each. Characteristics of ADR, incidence, causality and possible preventability, have been evaluated.

Results: 72 patients have been treated with at least one study drug, and 159 ADR episodes involving at least one of these drugs have been identified, with a total of 293 ADR. Most episodes required hospital admission (35.2%) or happened during the hospital stay (33%), and 91.2% were severe. Blood disorders were the most frequent ADR (96; 32.8%), related to thioguanine (42) and pegaspargase (39) mainly, followed by infections (86; 29.4%) related to thioguanine (32), pegaspargase (27), Erwinia asparaginase (14) and rituximab (13). Two ADR were unknown. Most ADR were dose-dependent or expectable (>90%). The global incidence of ADR was 3.1/100 days at risk (95% CI 2.7–3.5), with 3.5 ADR/100 days at risk with pegaspargase (95% CI 2.9–4.2), 1.2/100 days at risk with rituximab (95% CI 0.8–1.8) and 11.6/100 days at risk with thioguanine (95% CI 9.4–14.2). Controversial additional measures of prevention, other than those already used, were identified.

Conclusion: ADR are frequent in pediatric oncohematological patients, mainly blood disorders and infectious diseases. Findings regarding incidence and preventability may be useful to compare data between different centers and to evaluate new possibilities for action or prevention.

Chemotherapy-Related Adverse Drug Reaction and Associated Factors Among Hospitalized Paediatric Cancer Patients at Hospitals in North-West Ethiopia

BACKGROUND

One of the prevalent treatment modalities for cancer is chemotherapy. Adverse drug reactions, however, are becoming the world's major public health problem. More than half (54.5 percent) of cancer patients need hospitalization for further management, in addition to the increased health-care costs of treatment. The aim of this study was to evaluate adverse drug reactions associated with chemotherapy and related factors in hospitalized paediatric cancer patients in Ethiopia's north-west hospitals.

METHODS

From July 1, 2017, to August 13, 2019, a cross-sectional study was carried out among 311 paediatric cancer patients at Gondar Comprehensive University, Specialized Hospital and Felegehiwot referral hospital. The data were entered into Epi Info version 7 and exported for further analysis to Statistical Product and Service Solutions (SPSS). To identify associated variables, both the bi-variate and multi-variate logistic regression analyses were computed. Variables with a P-value of less than 0.05 were considered statistically significant in the multivariate logistic regression analysis.

RESULTS

The overall adverse drug reaction in this study was 41.5 percent ((95% CI: 35.8-47.2%)). Patients who received concomitant medications were at higher risk of experiencing adverse drug reactions (AOR: 2.60 (95% CI: 1.54-4.40)), according to the multivariate logistic regression analysis. Similarly, there was a risk of developing adverse drug reactions in patients taking four or more chemotherapy agents (AOR: 2.67 (95% CI: 1.52-4.68)). In addition, regimens based on etoposide (AOR: 1.99 (95% CI: 0.93-4.27)), mercaptopurine (AOR: 3.91 (95% CI: 1.06-14.46)) and doxorubicin (AOR: 2.32 (95% CI: 1.30-4.15)) were at higher risk for adverse drug reactions in patients.

CONCLUSION

Adverse drug reactions developed in a significant proportion of the study patients (2 out of 5 patients). Therefore, for pediatric cancer patients on concomitant medications and for patients on etoposide, mercaptopurine and doxorubicin drug regimens, efficient prevention and management of adverse drug reactions should be sought.

Supportive care medications coinciding with chemotherapy among children with hematologic malignancy

Pharmacokinetic (PK) conflicts can arise between supportive care medications (SCM) and chemotherapy in children with hematologic malignancy (HM). In this retrospective study, medical records for children (28 days-18 years) diagnosed with HM and receiving an SCM antimicrobial were collected from a hospital network between 1 May 2000 and 31 December 2014. PK drug-gene associations were obtained from a curated pharmacogenomics database. Among 730 patients (median age of 7.5 (IQR 3.7-13.9) years), primarily diagnosed with lymphoid leukemia (52%), lymphoma (28%), or acute myeloid leukemia (16%), chemotherapy was administered in 2846 hospitalizations. SCM accounted for 90.5% (n = 448) of distinct drugs with 93% (n = 679) of children, receiving ≥5 different SCM/hospitalization. Same-day SCM/chemotherapeutic PK gene overlap occurred in 48.3% of hospitalizations and was associated with age (p = 0.026), number of SCM, HM subtype, surgery, and hematopoietic stem cell transplant (p < 0.0001). A high and variable SCM burden among children with HM receiving chemotherapy poses a risk for unanticipated PK conflicts.

Insights into the Roles of Midazolam in Cancer Therapy

With its high worldwide mortality and morbidity, cancer has gained increasing attention and novel anticancer drugs have become the focus for cancer research. Recently, studies have shown that most anesthetic agents can influence the activity of tumor cells. Midazolam is a γ-aminobutyric acid A (GABA_A) receptor agonist, used widely for preoperative sedation and as an adjuvant during neuraxial blockade. Some studies have indicated the potential for midazolam as a novel therapeutic cancer drug; however, the mechanism by which midazolam affects cancer cells needs to be clarified. This systematic review aims to summarize the progress in assessing the molecular mechanism of midazolam as an anticancer agent.

Use of Modeling and Simulation in the Design and Conduct of Pediatric Clinical Trials and the Optimization of Individualized Dosing Regimens

Mathematical models of drug action and disease progression can inform pediatric pharmacotherapy. In this tutorial, we explore the key issues that differentiate pediatric from adult pharmacokinetic (PK) / pharmacodynamic (PD) studies, describe methods to calculate the number of participants to be enrolled and the optimal times at which blood samples should be collected, and therapeutic drug monitoring methods for individualizing pharmacotherapy. The development of pediatric-specific drug dosing dashboards is also highlighted, with an emphasis on clinical-relevance and ease of use.

Pretreatment but not subsequent coincubation with midazolam reduces the cytotoxicity of temozolomide in neuroblastoma cells

Background

Temozolomide (TMZ) induces a G2/M cell cycle arrest and is used for treatment of paediatric tumours, especially neuroblastomas. Patients treated with TMZ frequently receive midazolam for sedation prior to surgery and other interventions. Previous studies suggested both cytoprotective and apoptosis-inducing properties of midazolam. Therefore, the impact of midazolam on TMZ-induced cytotoxicity was investigated in vitro.

Methods

Human neuroblastoma cells were incubated with midazolam alone, as a pretreatment prior to incubation with TMZ or a coincubation of both. Cell viability and proliferation was analysed (XTT and BrdU assay) after 24 h and flowcytometric cell cycle analysis was performed after 24 and 48 h.

Results

Midazolam alone increased cell viability at lower concentrations (2, 4, 8, 16 μM), whereas higher concentrations (128, 256, 512 μM) reduced cell viability. Pretreatment with midazolam 6 h prior to TMZ incubation reduced cytotoxic effects (IC₂₅ 1005 ± 197 μM; IC₅₀ 1676 ± 557 μM; P < 0.05) compared to incubation with TMZ alone (IC₂₅ 449 ± 304 μM; IC₅₀ 925 ± 196 μM) and reduced the antiproliferative effect of TMZ (1000 μM) by 43.9 % (P < 0.05). In contrast, cytotoxic effects of TMZ were increased (IC₇₅ 1175 ± 221 μM vs. 2764 ± 307 μM; P < 0.05) when midazolam pretreatment was followed by coincubation of midazolam and TMZ. Cell cycle analysis revealed increased fractions of cells in G2/M phase after TMZ treatment (100 μM; 48 h), irrespective of midazolam pretreatment.

Conclusion

Midazolam causes a hormetic dose–response relationship in human neuroblastoma cells. Pretreatment with midazolam reduces the cytotoxic and antiproliferative effects of TMZ without interfering with G2/M cell cycle arrest. In contrast, subsequent midazolam coincubation increases overall cytotoxicity.

Neurocognitive outcomes in long-term survivors of childhood acute lymphoblastic leukemia treated on contemporary treatment protocols: A systematic review

The intensified administration of chemotherapeutic drugs has gradually replaced cranial radiation therapy (CRT) for the treatment of childhood acute lymphoblastic leukemia (ALL). While CRT is often implicated in neurocognitive impairment in ALL survivors, there is a paucity of the literature that evaluates the persistence of neurocognitive deficits in long-term survivors of pediatric ALL who were treated with contemporary chemotherapy-only protocols. Results from this systematic review concurred to the probable cognitive-sparing effect of chemotherapy-based protocols over CRT in long-term survivors. However, coupled with multiple intrinsic and extrinsic factors, survivors who received chemotherapy treatment still suffered from apparent cognitive impairment, particularly in the attention and executive function domains. Notably, there is evidence to suggest that the late neurotoxic effect of methotrexate on survivors' neurocognitive performance may be dose-related. This review also recommends future pharmacokinetic, neuroimaging and genetic studies to illuminate the multifactorial nature of this subject matter and discusses the potential value of neurochemical, physiological, inflammatory and genetic markers for the prediction of susceptibility to neurocognitive impairment in long-term survivors of childhood ALL.

Age-related toxicity in patients with rhabdomyosarcoma: a report from the children's oncology group

On the Fourth Intergroup Rhabdomyosarcoma study, older children experienced excessive neurotoxicity, whereas younger children had increased myelosuppression. The purpose of this study was to determine whether the same pattern of toxicity was seen on the successor study when use of growth factor was required and dosing of chemotherapy was different by performing a retrospective cohort analysis on patients treated on Children's Oncology Group protocol D9803. Toxicity data were analyzed by stratifying children into 4 age groups. The frequency of grade 3/4 neurotoxicity, myelosuppression, infection, and mucositis was predicted for each age group. The cumulative doses of vincristine and cyclophosphamide administered were measured as percent of protocol-prescribed dose. Adolescents (aged 15+) were more likely to experience neurotoxicity compared with younger patients (odds ratio, 3.6; P<0.0001). There was no difference in myelosuppression, infection, or mucositis. The mean percent protocol-prescribed doses administered for vincristine and cyclophosphamide did not differ much by age group. Adolescents experienced more neurotoxicity with vincristine compared with younger patients. No differences in other toxicities were observed between age groups. As adolescents received at least 85% of protocol-prescribed doses of vincristine, it is difficult to attribute the poorer survival in this age group to inadequate protocol-delivered therapy.