Clinical and histopathologic analysis of 46 cases of cutaneous adverse reactions to imatinib

The Application of Virtual Therapeutic Drug Monitoring to Assess the Pharmacokinetics of Imatinib in a Chinese Cancer Population Group

PURPOSE

Imatinib is used in gastrointestinal stromal tumours (GIST) and chronic myeloid leukaemia (CML). Oncology patients demonstrate altered physiology compared to healthy adults, e.g. reduced haematocrit, increased α-1 acid glycoprotein, decreased albumin and reduced glomerular filtration rate (GFR), which may influence imatinib pharmacokinetics. Given that Chinese cancer patients often report raised imatinib plasma concentrations and wider inter-individual variability reported in trough concentration when compared to Caucasian cancer patients, therapeutic drug monitoring (TDM) has been advocated.

METHOD

This study utilised a previously validated a Chinese cancer population and assessed the impact of imatinib virtual-TDM in Chinese and Caucasian cancer populations across a dosing range from 200-800 mg daily.

RESULTS

Staged dose titration to 800 mg daily, resulted in recapitulation to within the target therapeutic range for 50 % (Chinese) and 42.1% (Caucasian) subjects possessing plasma concentration < 550 ng/mL when dosed at 400 mg daily. For subjects with plasma concentrations >1500 ng/mL when dosed at 400 mg daily, a dose reduction to 200 mg once daily was able to recover 67 % (Chinese) and 87.4 % (Caucasian) patients to the target therapeutic range.

CONCLUSION

Virtual TDM highlights the benefit of pharmacokinetic modelling to optimising treatments in challenging oncology population groups.

9.4 T static magnetic field ameliorates imatinib mesylate-induced toxicity and depression in mice

PURPOSE

9.4 T magnetic resonance imaging (MRI) has been initially tested on healthy human volunteers, but its future application will benefit more from experiments with animal disease models. In the meantime, high static magnetic fields (SMFs) have been shown to improve mice mental health and have anti-tumor potentials.

METHODS

We compared the anti-tumor effects of 9.4 T SMF with or without a commonly used chemotherapy drug imatinib mesylate on BALB/c (Nu/Nu) mice bearing gastrointestinal stromal tumor GIST-T1 cells. The body weight, food/water consumption, complete blood count, blood biochemistry, tumor weight, HE and Ki67 stains were examined. Locomotor activity and cognitive functions were also measured by four behavior tests, including open field, elevated plus maze, three-chamber and tail suspension tests.

RESULTS

We found that the tumor growth was inhibited up to 62.88% when treated with 9.4 T SMF alone for 200 h. More importantly, 9.4 T SMF combined with 20 mg/kg imatinib mesylate can result in 92.75% tumor suppression, which is close to the anti-tumor effect of high dose (80 mg/kg) imatinib. However, 80 mg/kg imatinib caused severe side effects, including significantly reduced gain of body weight, abnormal liver function and depressive behaviors in mice. In contrast, 9.4 T SMF treatment significantly reduced these side effects, especially for the depressive behaviors.

CONCLUSION

Our results demonstrate that 9.4 T SMF not only has anti-tumor effects on its own, but also could improve the anti-tumor effect of imatinib mesylate, reduce its toxicity and improve the mice mental health, which unraveled the great clinical potentials of high SMF in future applications.

French guidelines for the management of oral lichen planus (excluding pharmacological therapy)

INTRODUCTION

Oral lichen is a chronic inflammatory disease for which diagnostic management and follow-up are heterogeneous given the absence of specific guidelines in France. Our objective was to develop French multidisciplinary guidelines for the management of oral lichen.

MATERIALS AND METHODS

Working groups from the Groupe d'Etude de la Muqueuse Buccale (GEMUB) formulated a list of research questions and the corresponding recommendations according to the "formal consensus" method for developing practice guidelines. These recommendations were submitted to a group of experts and the degree of agreement for each recommendation was assessed by a scoring group.

RESULTS

Twenty-two research questions, divided into 3 themes (nosological classification and initial assessment, induced oral lichenoid lesions, and follow-up) resulted in 22 recommendations. Initial biopsy for histology is recommended in the absence of reticulated lesions. Biopsy for direct immunofluorescence is recommended for ulcerated, erosive, bullous types and for diffuse erythematous gingivitis. Management should include a periodontal and dental check-up, and investigation for extra-oral lesions. Hepatitis C testing is recommended only if risk factors are present. Definitions, triggering factors and the management of "induced oral lichenoid lesions" were clarified. Oral lichen must be monitored by a practitioner familiar with the disease at least once a year, using objective tools.

CONCLUSION

This formalised consensus of multidisciplinary experts provides clinical practice guidelines on the management and monitoring of oral lichen.

A Case Report of Multiple Capillary Hemangioma in a Chronic Myeloid Leukemia Patient Taking Tyrosine Kinase Inhibitors

A capillary hemangioma is a vascular tumor with small capillary sized vascular channel. Multiple capillary hemangioma in relation with drugs have been rarely reported. Here in, we report a case of multiple capillary hemangioma in patient diagnosed with chronic myeloid leukemia who received tyrosine kinase inhibitors (TKIs). Histopathological findings have shown capillary proliferation in the upper dermis, which is consistent with capillary hemangioma. Since TKIs can paradoxically activate the MEK/ERK pathway which is required for angiogenesis, we presumed that the lesions as the cutaneous side effects of TKIs.

Systemic Steroid Treatment for Imatinib-Associated Severe Skin Rash in Patients with Gastrointestinal Stromal Tumor: A Phase II Study

BACKGROUND

To achieve optimal clinical outcomes in patients with gastrointestinal stromal tumor (GIST), it is crucial to maintain sufficient dosing of imatinib. Skin rash is a common imatinib-associated adverse event and may affect compliance. This phase II study was conducted to evaluate whether imatinib-associated severe skin rash can be managed with systemic steroids without dose reduction or interruption of imatinib. This study is registered at ClinicalTrials.gov, number NCT03440515.

PATIENTS AND METHODS

Between 2014 and 2016, 29 patients with imatinib-associated severe skin rash were enrolled. Skin rash of grade 2 with grade ≥2 pruritus or of grade 3 was considered severe. Oral prednisolone was administered 30 mg/day for 3 weeks, then tapered off over 12 weeks. The primary endpoint was treatment success rate (TSR). Treatment success was defined as maintaining imatinib for more than 15 weeks after completion of the steroid administration schedule without skin rash that led to additional steroid treatment or dose reduction or interruption of imatinib.

RESULTS

Of the 29 patients enrolled, 22 patients with skin rash were treated successfully (TSR, 75.8%), 2 (6.9%) were evaluated as treatment failures, and 5 (17.2%) were not evaluable. The 2-year rash-free and imatinib reduction-free interval rate was 67.2% with median follow-up of 22.0 months (range, 0.4-30.3). Recurrence of severe skin rash occurred in seven patients (24.1%). Systemic steroids were well tolerated except in one patient who experienced pneumocystis pneumonia.

CONCLUSION

This study demonstrated that imatinib-associated severe skin rash can be effectively controlled by systemic steroid treatment without interruption or dose reduction of imatinib in patients with GIST.

IMPLICATIONS FOR PRACTICE

Imatinib has been the standard treatment of gastrointestinal stromal tumor in both adjuvant and palliative settings. It is crucial to maintain sufficient dosing of imatinib to achieve optimal clinical outcomes. Imatinib commonly causes imatinib-associated skin rash, which may worsen drug compliance. This phase II study demonstrated that systemic steroids could help maintaining the efficacy of imatinib by preventing interruption or dose reduction of imatinib. The present study provides a new administration strategy of systemic steroids and its efficacy and safety data. Thus, this study can be a cornerstone to establish treatment guidelines for imatinib-associated skin rash.

Therapeutic drug monitoring-based dose optimization for imatinib-associated serious cutaneous reactions in a patient with gastrointestinal stromal tumours: A case report

WHAT IS KNOWN AND OBJECTIVE

Imatinib mesylate (IM) is the first-line therapy for unresectable or metastatic gastrointestinal stromal tumours (GISTs). Here, we report a case of successful progressive dose optimization by therapeutic drug monitoring (TDM) for a patient with GISTs who developed IM-associated serious cutaneous reactions.

CASE DESCRIPTION

A 72-year-old female patient received IM at a dose of 400 mg/day for GISTs. The patient developed serious eczematoid drug eruptions and desquamation, following which IM was discontinued. One year later, the GISTs recurred with metastasis, and IM was re-administered at a dose of 100 mg/day, and the dose was gradually increased on the basis of TDM. The final dose of IM was 200 mg/day, and the trough concentration (C_trough ) of IM was 1457.76 ng/mL. The images obtained from follow-up computed tomography (CT) showed a marked anti-tumour response. IM was well tolerated and the patient developed tolerable IM-associated cutaneous reactions.

WHAT IS NEW AND CONCLUSION

The strategy of TDM-guided dose optimization makes it possible to achieve optimal clinical efficacy for patients with GISTs who develop IM-associated serious cutaneous reactions.

Arg mediates LPS-induced disruption of the pulmonary endothelial barrier

Acute Respiratory Distress Syndrome (ARDS) is a devastating disease process that involves dysregulated inflammation and decreased alveolar-capillary barrier function. Despite increased understanding of the pathophysiology, no effective targeted therapies exist to treat ARDS. Recent preclinical studies suggest that the multi-tyrosine kinase inhibitor, imatinib, which targets the Abl kinases c-Abl and Arg, has the potential to restore endothelial dysfunction caused by inflammatory agonists. Prior work demonstrates that imatinib attenuates LPS (lipopolysaccharide)-induced vascular leak and inflammation; however, the mechanisms underlying these effects remain incompletely understood. In the current study, we demonstrate that imatinib inhibits LPS-induced increase in the phosphorylation of CrkL, a specific substrate of Abl kinases, in human pulmonary endothelial cells. Specific silencing of Arg, and not c-Abl, attenuated LPS-induced pulmonary vascular permeability as measured by electrical cellular impedance sensing (ECIS) and gap formation assays. In addition, direct activation of Abl family kinases with the small molecule activator DPH resulted in endothelial barrier disruption that was attenuated by Arg siRNA. In complementary studies to characterize the mechanisms by which Arg mediates endothelial barrier function, Arg silencing was found to inhibit LPS-induced disruption of adherens junctions and phosphorylation of myosin light chains (MLC). Overall, these results characterize the mechanisms by which imatinib protects against LPS-induced endothelial barrier disruption and suggest that Arg inhibition may represent a novel strategy to enhance endothelial barrier function.