Tyrosine kinase inhibitors and drug interactions: a review with practical recommendations

Characterization and optimization of magnetic molecularly imprinted nanofibers for determination of sunitinib in human serum and capsule samples

This article reports a spectrofluorometric method for the determination of sunitinib (STB) drug based on molecularly imprinted nanofibers fabricated by the electrospinning method and modified by magnetic nanoparticles as sorbent. The characterization of magnetic molecularly imprinted nanofibers (MMINs) was carried out using X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscopy (TEM), which confirmed the successful synthesis of MMINs with well-distributed magnetite nanoparticles. Drug adsorption and desorption were optimized and important parameters such as sample pH, nanofiber mass, adsorption and desorption time, eluent solvent and sample volume were analyzed. The results demonstrated that the MMINs act as a selective sorbent for STB and can be readily collected through an external magnetic field. Methanol was used as the best eluent solvent for STB desorption from MNIN. A linear correlation was observed between the STB concentrations and fluorescence intensities in the range of 0.01-15.0 mg L-1. The detection limit for this method was 0.002 mg L-1. The relative standard deviation (RSD) of 2.6 % for 1.0 mg L-1 and 1.1 % for 10 mg L-1 of STB (n = 3) were obtained, which indicates that the developed method is precise in determining STB. Human serum and capsule analysis show the applicability of the proposed sensor for real samples.

A clinical overview of people living with HIV and genitourinary cancer care

The number of people living with HIV infection has been increasing globally. Administration of antiretroviral therapy is effective in controlling the infection for most patients and, as a consequence, people living with HIV (PLWH) now often have a long life expectancy. However, their risk of developing cancer - most notably virus-related cancers - has been increasing. To date, few studies have assessed the risk of genitourinary cancers in PLWH, and robust scientific data on their treatment-related outcomes are lacking. Previous studies have noted that PLWH are at a reduced risk of prostate cancer; however, low adoption and/or availability of prostate cancer screening among these patients might be confounding the validity of this finding. In genitourinary cancers, advanced stage at diagnosis and reduced cancer-specific mortality have been reported in PLWH. These data likely reflect, at least in part, the inequity of health care access for PLWH. Notably, systemic chemotherapy and/or radiotherapy could decrease total CD4+ cell counts, which could, therefore, increase the risk of morbidity and mortality from cancer treatments in PLWH. Immune checkpoint inhibitors have become the therapeutic backbone for many advanced malignancies in the general population; however, most studies validating their efficacy have excluded PLWH owing to concerns of severe adverse effects from immune checkpoint inhibitors themselves and/or related to their immunosuppressed status. To our knowledge, no genitourinary cancer survivorship programme exists that specifically caters to the needs of PLWH. By including PLWH in ongoing cancer trials, we can gain invaluable insights that will help to improve cancer care specifically for PLWH.

How to Manage Philadelphia-Positive Acute Lymphoblastic Leukemia in Resource-Constrained Settings

Recent studies have indicated that more than half of adult patients newly diagnosed with Ph+ ALL can now achieve a cure. However, determining the most suitable protocol for less-resourced settings can be challenging. In these situations, we must consider the potential for treatment toxicity and limited access to newer agents and alloSCT facilities. Currently, it is advisable to use less intensive induction regimens for Ph+ ALL. These regimens can achieve high rates of complete remission while causing fewer induction deaths. For consolidation therapy, chemotherapy should remain relatively intensive, with careful monitoring of the BCR-ABL1 molecular transcript and minimal residual disease. AlloSCT may be considered, especially for patients who do not achieve complete molecular remission or have high-risk genetic abnormalities, such as IKZF1-plus. If there is a loss of molecular response, it is essential to screen patients for ABL mutations and, ideally, change the TKI therapy. The T315I mutation is the most common mechanism for disease resistance, being targetable to ponatinib. Blinatumomab, a bispecific antibody, has shown significant synergy with TKIs in treating this disease. It serves as an excellent salvage therapy, aside from achieving outstanding results when incorporated into the frontline.

A review of prophylactic regimens to prevent invasive fungal infections in hematology patients undergoing chemotherapy or stem cell transplantation

INTRODUCTION

The recent introduction of targeted therapies, including monoclonal antibodies, tyrosine-kinase inhibitors, and immunotherapies has improved the cure rate of hematologic patients. The implication of personalized treatment on primary antifungal prophylaxis will be discussed.

AREAS COVERED

We reviewed the literature for clinical trials reporting the rate of invasive fungal infections during targeted and cellular therapies and stem cell transplant, and the most recent international guidelines for primary antifungal prophylaxis.

EXPERT OPINION

As the use of personalized therapies is growing, the risk of invasive fungal infection has emerged in various clinical settings. Therefore, it is possible that the use of mold-active antifungal prophylaxis would spread in the next years and the risk of breakthrough infections would increase. The introduction of new antifungal agents in the clinical armamentarium is expected to reduce clinical unmet needs concerning the management of primary antifungal prophylaxis and improve outcome of patients.

When Azoles Cannot Be Used: The Clinical Effectiveness of Intermittent Liposomal Amphotericin Prophylaxis in Hematology Patients

Background

Patients unable to take azoles are a neglected group lacking a standardized approach to antifungal prophylaxis. We evaluated the effectiveness and safety of intermittent liposomal amphotericin B (L-AMB) prophylaxis in a heterogenous group of hematology patients.

Methods

A retrospective cohort of all hematology patients who received a course of intravenous L-AMB, defined as 1 mg/kg thrice weekly from July 1, 2013 to June 30, 2018, were identified from pharmacy records. Outcomes included breakthrough-invasive fungal disease (BIFD), reasons for premature discontinuation, and acute kidney injury.

Results

There were 198 patients who received 273 courses of L-AMB prophylaxis. Using a conservative definition, the BIFD rate was 9.6% (n = 19 of 198) occurring either during L-AMB prophylaxis or up to 7 days from cessation in patients who received a course. Probable/proven BIFD occurred in 13 patients (6.6%, 13 of 198), including molds in 54% (n = 7) and non-albicans Candidemia in 46% (n = 6). Cumulative incidence of BIFD was highest in patients with acute myeloid leukemia (6.8%) followed by acute lymphoblastic leukemia (2.7%) and allogeneic stem cell transplantation (2.5%). The most common indication for L-AMB was chemotherapy, or anticancer drug-azole interactions (75% of courses) dominated by vincristine, or acute myeloid leukemia clinical trials, followed by gut absorption concerns (13%) and liver function abnormalities (8.8%). Acute kidney injury, using a modified international definition, complicated 27% of courses but was not clinically significant, accounting for only 3.3% (9 of 273) of discontinuations.

Conclusions

Our findings demonstrate a high rate of BIFD among patients receiving L-AMB prophylaxis. Pragmatic trials will help researchers find the optimal regimen of L-AMB prophylaxis for the many clinical scenarios in which azoles are unsuitable, especially as targeted anticancer drugs increase in use.

Infectious Complications of Biological and Small Molecule Targeted Immunomodulatory Therapies

The past 2 decades have seen a revolution in our approach to therapeutic immunosuppression. We have moved from relying on broadly active traditional medications, such as prednisolone or methotrexate, toward more specific agents that often target a single receptor, cytokine, or cell type, using monoclonal antibodies, fusion proteins, or targeted small molecules. This change has transformed the treatment of many conditions, including rheumatoid arthritis, cancers, asthma, and inflammatory bowel disease, but along with the benefits have come risks. Contrary to the hope that these more specific agents would have minimal and predictable infectious sequelae, infectious complications have emerged as a major stumbling block for many of these agents. Furthermore, the growing number and complexity of available biologic agents makes it difficult for clinicians to maintain current knowledge, and most review articles focus on a particular target disease or class of agent. In this article, we review the current state of knowledge about infectious complications of biologic and small molecule immunomodulatory agents, aiming to create a single resource relevant to a broad range of clinicians and researchers. For each of 19 classes of agent, we discuss the mechanism of action, the risk and types of infectious complications, and recommendations for prevention of infection.

European guidelines for primary antifungal prophylaxis in adult haematology patients: summary of the updated recommendations from the European Conference on Infections in Leukaemia

The European Conference on Infections in Leukaemia (ECIL) updated its guidelines on antifungal prophylaxis for adults using the grading system of IDSA. The guidelines were extended to provide recommendations for other haematological diseases besides AML and recipients of an allogeneic haematopoietic stem cell transplantation (HSCT). Posaconazole remains the drug of choice when the incidence of invasive mould diseases exceeds 8%. For patients undergoing remission-induction chemotherapy for AML and myelodysplastic syndrome (MDS), fluconazole can still offer an alternative provided it forms part of an integrated care strategy that includes screening with biomarkers and imaging. Similarly, aerosolized liposomal amphotericin B combined with fluconazole can be considered for patients at high risk of invasive mould diseases but other formulations of the polyene are discouraged. Fluconazole is still recommended as primary prophylaxis for patients at low risk of invasive mould diseases during the pre-engraftment phase of allogeneic HSCT whereas only a moderate recommendation could be made for itraconazole, posaconazole and voriconazole for patients at high risk. Posaconazole is strongly recommended for preventing invasive mould disease post-engraftment but only when graft-versus-host disease (GvHD) was accompanied by other risk factors such as its severity, use of an alternative donor or when unresponsive to standard corticosteroid therapy. The need for primary prophylaxis for other patient groups was less clear and should be defined by the estimated risk of invasive fungal disease (IFD).

Diclofenac Potentiates Sorafenib-Based Treatments of Hepatocellular Carcinoma by Enhancing Oxidative Stress

Sorafenib is the first developed systemic treatment for advanced forms of hepatocellular carcinoma, which constitutes the most frequent form of primary liver cancers and is a major global health burden. Although statistically significant, the positive effect of sorafenib on median survival remains modest, highlighting the need to develop novel therapeutic approaches. In this report, we introduce diclofenac, a nonsteroidal anti-inflammatory drug, as a potent catalyzer of sorafenib anticancer efficacy. Treatment of three different hepatocellular cancer cells (Huh-7, HepG2, and PLC-PRF-5) with sorafenib (5 µM, 24 h) and diclofenac (100 µM, 24 h) significantly increased cancer cell death compared to sorafenib or diclofenac alone. Anti-oxidant compounds, including N-acetyl-cysteine and ascorbic acid, reversed the deleterious effects of diclofenac/sorafenib co-therapy, suggesting that the generation of toxic levels of oxidative stress was responsible for cell death. Accordingly, whereas diclofenac increased production of mitochondrial oxygen reactive species, sorafenib decreased concentrations of glutathione. We further show that tumor burden was significantly diminished in mice bearing tumor xenografts following sorafenib/diclofenac co-therapy when compared to sorafenib or diclofenac alone. Taken together, these results highlight the anticancer benefits of sorafenib/diclofenac co-therapy in hepatocellular carcinoma. They further indicate that combining sorafenib with compounds that increase oxidative stress represents a valuable treatment strategy in hepatocellular carcinoma.

Combination therapy for metastatic melanoma: a pharmacist's role, drug interactions & complementary alternative therapies

The incidence of metastatic melanoma has been increasing dramatically over the last decades. Yet, there have been many new innovative therapies, such as targeted therapies and checkpoint inhibitors, which have made progress in survival for these patients. The oncology pharmacist is part of the healthcare team and can help in optimizing these newer therapies. There will be discussion about combination therapies, the oncology pharmacist's role, and issues at the core of his interest, such as drug interactions and complementary and alternative therapies.

Therapeutic drug monitoring and tyrosine kinase inhibitors

The therapeutic activity of drugs can be optimized by establishing an individualized dosage, based on the measurement of the drug concentration in the serum, particularly if the drugs are characterized by an inter-individual variation in pharmacokinetics that results in an under- or overexposure to treatment. In recent years, several tyrosine kinase inhibitors (TKIs) have been developed to block intracellular signaling pathways in tumor cells. These oral drugs are candidates for therapeutic drug monitoring (TDM) due to their high inter-individual variability for therapeutic and toxic effects. Following a literature search on PubMed, studies on TKIs and their pharmacokinetic characteristics, plasma quantification and inter-individual variability was studied. TDM is commonly used in various medical fields, including cardiology and psychiatry, but is not often applied in oncology. Plasma concentration monitoring has been thoroughly studied for imatinib, in order to evaluate the usefulness of TDM. The measurement of plasma concentration can be performed by various analytical techniques, with liquid chromatography-mass spectrometry being the reference method. This method is currently used to monitor the efficacy and tolerability of imatinib treatments. Although TDM is already being used for imatinib, additional studies are required in order to improve this practice with the inclusion of other TKIs.

Omacetaxine Mepesuccinate for Chronic Myeloid Leukemia

Omacetaxine mepesuccinate is approved by the Food and Drug Administration in the United States for the treatment of chronic myeloid leukemia in chronic or accelerated phase resistant to two or more tyrosine kinase inhibitors. This review summarizes the mode of action, pharmacokinetics, efficacy and safety of omacetaxine mepesuccinate. Omacetaxine mepesuccinate has activity in chronic myeloid leukemia, especially in the chronic phase, regardless of the presence of ABL1 kinase domain mutations. Omacetaxine mepesuccinate has distinct but manageable adverse events profile. Omacetaxine mepesuccinate is a treatment option for a subset of patients with refractory chronic myeloid leukemia.

Kinase inhibitors and monoclonal antibodies in oncology: clinical implications

Molecularly targeted cancer therapies, such as small-molecule kinase inhibitors and monoclonal antibodies, constitute a rapidly growing and an important part of the oncology armamentarium. Unlike conventional (cytotoxic) chemotherapeutics, targeted therapies were designed to disrupt cancer cell pathogenesis at specific biological points essential for the development and progression of the tumour. These agents were developed to disrupt specific targets with the aim of minimizing treatment burden compared with conventional chemotherapy. Nevertheless the increasingly common use of targeted therapies has revealed some unanticipated, often clinically significant toxic effects, as well as compromising effective palliative and end-of-life management approaches. Although patients and clinicians welcome improvements in cancer prognosis, these changes can also impact patient quality-of-life. Therefore, as demand for oncology expertise increases, physicians need to apprise themselves of targeted therapies and their clinical implications, including drug-specific side effects, impact on quality of life, and cost issues, especially in relation to end-of-life care. This Review provides a useful summary and guide for professionals treating patients with malignant diseases.

Metabolism-related pharmacokinetic drug-drug interactions with tyrosine kinase inhibitors: current understanding, challenges and recommendations

Drug-drug interactions (DDIs) occur when a patient's response to the drug is modified by administration or co-exposure to another drug. The main cytochrome P450 (CYP) enzyme, CYP3A4, is implicated in the metabolism of almost all of the tyrosine kinase inhibitors (TKIs). Therefore, there is a substantial potential for interaction between TKIs and other drugs that modulate the activity of this metabolic pathway. Cancer patients are susceptible to DDIs as they receive many medications, either for supportive care or for treatment of toxicity. Differences in DDI outcomes are generally negligible because of the wide therapeutic window of common drugs. However for anticancer agents, serious clinical consequences may occur from small changes in drug metabolism and pharmacokinetics. Therefore, the objective of this review is to highlight the current understanding of DDIs among TKIs, with a focus on metabolism, as well as to identify challenges in the prediction of DDIs and provide recommendations.

Label-Free Raman Spectroscopic Imaging Monitors the Integral Physiologically Relevant Drug Responses in Cancer Cells

Predictions about the cellular efficacy of drugs tested in vitro are usually based on the measured responses of a few proteins or signal transduction pathways. However, cellular proteins are highly coupled in networks, and observations of single proteins may not adequately reflect the in vivo cellular response to drugs. This might explain some large discrepancies between in vitro drug studies and drug responses observed in patients. We present a novel in vitro marker-free approach that enables detection of cellular responses to a drug. We use Raman spectral imaging to measure the effect of the epidermal growth factor receptor (EGFR) inhibitor panitumumab on cell lines expressing wild-type Kirsten-Ras (K-Ras) and oncogenic K-Ras mutations. Oncogenic K-Ras mutation blocks the response to anti-EGFR therapy in patients, but this effect is not readily observed in vitro. The Raman studies detect large panitumumab-induced differences in vitro in cells harboring wild-type K-Ras as seen in A in red but not in cells with K-Ras mutations as seen in B; these studies reflect the observed patient outcomes. However, the effect is not observed when extracellular-signal-regulated kinase phosphorylation is monitored. The Raman spectra show for cells with wild-type K-Ras alterations based on the responses to panitumumab. The subcellular component with the largest spectral response to panitumumab was lipid droplets, but this effect was not observed when cells harbored K-Ras mutations. This study develops a noninvasive, label-free, in vitro vibrational spectroscopic test to determine the integral physiologically relevant drug response in cell lines. This approach opens a new field of patient-centered drug testing that could deliver superior patient therapies.

Clinical pharmacokinetics of tyrosine kinase inhibitors: implications for therapeutic drug monitoring

The treatment of many malignancies has been improved in recent years by the introduction of molecular targeted therapies. These drugs interact preferentially with specific targets that are mutated and/or overexpressed in malignant cells. A group of such targets are the tyrosine kinases, against which a number of inhibitors (tyrosine kinase inhibitors, TKIs) have been developed. Imatinib, a TKI with targets that include the breakpoint cluster region-Abelson (bcr-abl) fusion protein kinase and mast/stem cell growth factor receptor kinase (c-Kit), was the first clinically successful drug of this type and revolutionized the treatment and prognosis of chronic myeloid leukemia and gastrointestinal stromal tumors. This success paved the way for the development of other TKIs for the treatment of a range of hematological malignancies and solid tumors. To date, 14 TKIs have been approved for clinical use and many more are under investigation. All these agents are given orally and are substrates of a range of drug transporters and metabolizing enzymes. In addition, some TKIs are capable of inhibiting their own transporters and metabolizing enzymes, making their disposition and metabolism at steady-state unpredictable. A given dose can therefore give rise to markedly different plasma concentrations in different patients, favoring the selection of resistant clones in the case of subtherapeutic exposure, and increasing the risk of toxicity if dosage is excessive. The aim of this review was to summarize current knowledge of the clinical pharmacokinetics and known adverse effects of the TKIs that are available for clinical use and to provide practical guidance on the implications of these data in patient management, in particular with respect to therapeutic drug monitoring.

Drug interactions with sunitinib

PURPOSE

Sunitinib is a tyrosine kinase inhibitor indicated for the treatment of gastrointestinal stromal tumor, advanced renal cell carcinoma, and pancreatic neuroendocrine tumors. The aim of this article is to describe the pharmacological interactions between sunitinib and commonly prescribed drugs.

METHOD

We reviewed available information on pharmacological interactions between sunitinib and concomitantly prescribed drugs. Drugs were grouped into different therapeutic groups according to the Anatomical Therapeutic Chemical (ATC) classification.

RESULTS

Sunitinib interacts with CYP3A4 inducers or inhibitors and with P-glycoprotein and ABCG2 substrates. Pharmacodynamic interactions with drugs have also been found.

CONCLUSION

Current information on drug interactions between sunitinib and other drugs is scarce and most of the times it is difficult to apply to clinical practice. Even so, this difficulty in managing drug interactions should not be a reason to ignore them as they can help to explain intolerances and treatment failures.

Imatinib, dasatinib and nilotinib: a review of adverse cutaneous reactions with emphasis on our clinical experience

In the last years, several tyrosine kinase inhibitors (TKIs) have been developed and approved for human cancer treatment. Imatinib mesylate was the first of this novel family of drugs that target cancer-specific molecules and signalling pathways. The appearance of imatinib resistances led to the introduction of second-generation TKIs with higher potency and selectivity, such as dasatinib and nilotinib. However, the range of activity of these agents is not simply directed at tumour cells. Patients and their clinicians are indeed frequently confronted with the cutaneous side-effects associated with the employ of these drugs, which represent the most common non-hematological adverse reactions. For this reason, a systematic dermatological survey of patients receiving these therapies is highly important, and an early and appropriate dermatological treatment is required. In this review, we analyse the clinical and pathological characteristics of the most commonly reported adverse skin events associated with first- and second-generation tyrosine kinase inhibitors, with a particular emphasis on our clinical experience.

Twelve-month frequency of drug-metabolizing enzyme and transporter-based drug-drug interaction potential in patients receiving oral enzyme-targeted kinase inhibitor antineoplastic agents

OBJECTIVE

To describe 12-month rates and patterns of coprescription of drugs that potentially create drug-drug interactions (DDIs) through shared metabolic or transport pathways for 9 enzyme-targeted kinase inhibitor oral antineoplastic drugs (OADs).

PATIENTS AND METHODS

We used a deidentified pharmacy claims database identifying patients prescribed dasatinib, erlotinib, everolimus, imatinib, lapatinib, nilotinib, pazopanib, sorafenib, or sunitinib between January 1, 2008, and May 31, 2010. Coprescribing was 1 or more overlapping days of supply between the OAD and potential DDI drugs during the 12-month period beginning on the OAD index date. Product labels identified the cytochrome P450 metabolic enzymes used and whether P-glycoprotein was used by the OADs. Drugs that induce and/or inhibit these pathways were identified from the label and online resources.

RESULTS

Sample sizes ranged from 96 (pazopanib group) to 4617 (imatinib group). Coprescribing rates with drugs that may decrease OAD effectiveness were 359/1546 (23%) (sunitinib group) to 1851/3263 (57%) (erlotinib group). Coprescribing rates with drugs that may increase OAD toxicity were 364/1546 (24%) (sunitinib group) to 71/96 (74%) (pazopanib group). Patients coprescribed DDI drugs had a median of 1 to 4 more medications present on the OAD index date than those not coprescribed a DDI drug. Most groups coprescribed DDI drugs had a median of 180 or more OAD days of supply during follow-up. The proportion of OAD days of supply with overlapping days of DDI drugs ranged from 7% to 85%. Generally, oncologists prescribed the OAD and nononcologists the DDI drug.

CONCLUSION

Coprescription of drugs that induce or inhibit metabolic pathways used by enzyme-targeted kinase inhibitor OADs is high. The clinical consequences need further study.