Erlotinib treatment induces cytochrome P450 3A activity in non-small cell lung cancer patients

Improvement in static and dynamic projections of drug-drug interactions caused by cytochrome P4503A time-dependent inhibitors through in vitro allosteric modulation by progesterone

Current drug discovery screens to assess the drug-drug interaction (DDI) risk caused by time-dependent inhibition (TDI) of cytochrome P450 (CYP) 3A4 are known to overpredict or produce false positives that do not translate in vivo. Recent work identified that inclusion of the allosteric modulator progesterone (PGS), at a concentration of 45 μM to human liver microsomal incubations, generated in vitro TDI values that replicated clinical DDI predictions for 2 well established mechanism-based inhibitors. Further application of this approach across a diverse set of compounds was undertaken in this study, with 56 molecules reported in literature as time-dependent inhibitors in vitro tested in the human liver microsomal TDI kinetic assay in the absence and presence of 45 μM PGS. No TDI signal was observed for 15 molecules under control conditions despite literature reports. For the remaining compounds observed to have a TDI signal under control conditions, presence of PGS modified the inactivation efficiency for 36 compounds and eliminated the TDI signal for 5 compounds that were false positives. In vitro kinetic values were incorporated into mechanistic static and dynamic physiologically based pharmacokinetic models to project DDIs. TDI parameters established in the presence of PGS decreased the magnitude of overprediction while maintaining a high sensitivity (96% and 100%) for the detection of TDI with improved specificity (69% and 89%) when using mechanistic static and dynamic models, respectively. Inclusion of PGS into in vitro TDI assays provides a simple, rapid, and cost-effective solution for identifying true CYP3A4 TDIs and improving TDI-related DDI predictions. SIGNIFICANCE STATEMENT: The impact of the previously determined optimal concentration of the allosteric modulator progesterone (45 μM) was evaluated across a set of 56 compounds reported to be time-dependent inhibitors in vitro. In vitro generated values were incorporated into mechanistic static and physiologically based pharmacokinetic models to predict extent of drug-drug interactions and compared to clinical reports. Inclusion of progesterone into the assay identified in vitro false positives and improved risk predictions.

Investigating underlying molecular mechanisms, signaling pathways, emerging therapeutic approaches in pancreatic cancer

Pancreatic adenocarcinoma, a clinically challenging malignancy constitutes a significant contributor to cancer-related mortality, characterized by an inherently poor prognosis. This review aims to provide a comprehensive understanding of pancreatic adenocarcinoma by examining its multifaceted etiologies, including genetic mutations and environmental factors. The review explains the complex molecular mechanisms underlying its pathogenesis and summarizes current therapeutic strategies, including surgery, chemotherapy, and emerging modalities such as immunotherapy. Critical molecular pathways driving pancreatic cancer development, including KRAS, Notch, and Hedgehog, are discussed. Current therapeutic strategies, including surgery, chemotherapy, and radiation, are discussed, with an emphasis on their limitations, particularly in terms of postoperative relapse. Promising research areas, including liquid biopsies, personalized medicine, and gene editing, are explored, demonstrating the significant potential for enhancing diagnosis and treatment. While immunotherapy presents promising prospects, it faces challenges related to immune evasion mechanisms. Emerging research directions, encompassing liquid biopsies, personalized medicine, CRISPR/Cas9 genome editing, and computational intelligence applications, hold promise for refining diagnostic approaches and therapeutic interventions. By integrating insights from genetic, molecular, and clinical research, innovative strategies that improve patient outcomes can be developed. Ongoing research in these emerging fields holds significant promise for advancing the diagnosis and treatment of this formidable malignancy.

Multifaceted role of erlotinib in various cancer: nanotechnology intervention, patent landscape, and advancements in clinical trials

Erlotinib (ELB) is a tyrosine kinase inhibitor that targets the activity of Epidermal Growth Factor Receptor (EGFR) protein found in both healthy and cancerous cells. It binds reversibly to the ATP-binding site of the EGFR tyrosine kinase. ELB was approved by the US Food and Drug Administration (FDA) in 2004 for advanced non-small cell lung cancer (NSCLC) treatment in patients who relapsed after at least one other therapy. It was authorized for use with gemcitabine in 2005 for the treatment of advanced pancreatic cancer. In addition to lung cancer, ELB has shown promising results in the treatment of other cancers, including breast, prostate, colon, pancreatic, cervical, ovarian, and head and neck cancers. However, its limited water solubility, as a BCS class II drug, presents biopharmaceutical problems. Nanoformulations have been developed to overcome these issues, including increased solubility, controlled release, enhanced stability, tumor accumulation, reduced toxicity, and overcoming drug resistance. In older patients, ELB management should involve individualized dosing based on age-related changes in drug metabolism and close monitoring for adverse effects. Regular assessments of renal and hepatic functions are essential. This review provides an overview of ELB's role of ELB in treating various cancers, its associated biopharmaceutical issues, and the latest developments in ELB-related nanotechnology interventions. It also covers ELB patents granted in previous years and the ongoing clinical trials.

Pathological and pharmacological functions of the metabolites of polyunsaturated fatty acids mediated by cyclooxygenases, lipoxygenases, and cytochrome P450s in cancers

Oxylipins have garnered increasing attention because they were consistently shown to play pathological and/or pharmacological roles in the development of multiple cancers. Oxylipins are the metabolites of polyunsaturated fatty acids via both enzymatic and nonenzymatic pathways. The enzymes mediating the metabolism of PUFAs include but not limited to lipoxygenases (LOXs), cyclooxygenases (COXs), and cytochrome P450s (CYPs) pathways, as well as the down-stream enzymes. Here, we systematically summarized the pleiotropic effects of oxylipins in different cancers through pathological and pharmacological aspects, with specific reference to the enzyme-mediated oxylipins. We discussed the specific roles of oxylipins on cancer onset, growth, invasion, and metastasis, as well as the expression changes in the associated metabolic enzymes and the associated underlying mechanisms. In addition, we also discussed the clinical application and potential of oxylipins and related metabolic enzymes as the targets for cancer prevention and treatment. We found the specific function of most oxylipins in cancers, especially the underlying mechanisms and clinic applications, deserves and needs further investigation. We believe that research on oxylipins will provide not only more therapeutic targets for various cancers but also dietary guidance for both cancer patients and healthy humans.

Phase I study to evaluate of the gastric pH-dependent drug interaction between famitinib and the proton pump inhibitor omeprazole in healthy subjects

To evaluate the potential gastric pH-dependent drug-drug interaction (DDI), safety and tolerability of famitinib co-administered with omeprazole in healthy subjects. Twenty healthy subjects were enrolled in a single-center, single-arm, open-label, fixed-sequence study. Famitinib was administered as a single oral 25 mg under a fasting condition on day 1, omeprazole (40 mg once daily) was given on days 10-14, concomitantly with famitinib on day 15, and for the follow-up 7 additional days (days 16-22). Blood samples were collected for the pharmacokinetic analysis of famitinib and its metabolite SHR116637 following each famitinib dose. Safety and tolerability were assessed during the whole progress via clinical laboratory tests. The least-squares geometric mean ratios (GMRs) (90% CI) of C_max, AUC_0-t and AUC_0-∞ for famitinib combined with omeprazole to famitinib alone were 0.989 (0.953, 1.027), 0.956 (0.907, 1.007) and 0.953(0.905, 1.005) respectively. For the metabolite SHR116637, their GMRs (90% CI) of the above parameters were 0.851 (0.786, 0.920), 0.890 (0.838, 0.946)and 0.887 (0.835, 0.943), indicating the absence of significant differences in the parameters. During the treatment period, 9(45%) subjects reported 16 treatment emergent adverse events (TEAE), among which 6 subjects (30%) reported 9 TEAEs and 1 subject (5%) reported 1 TEAE during famitinib or omeprazole administered alone respectively, 5 subjects (25.0%) reported 6 TEAEs during in the combined administration phase. Omeprazole did not have a significant influence on the pharmacokinetics (PK) of famitinib and SHR116637, and the safety profile was good upon co-administration. ClinicalTrials.gov identifier NCT 05,041,920.

Integration of liquid biopsy and pharmacogenomics for precision therapy of EGFR mutant and resistant lung cancers

The advent of molecular profiling has revolutionized the treatment of lung cancer by comprehensively delineating the genomic landscape of the epidermal growth factor receptor (EGFR) gene. Drug resistance caused by EGFR mutations and genetic polymorphisms of drug metabolizing enzymes and transporters impedes effective treatment of EGFR mutant and resistant lung cancer. This review appraises current literature, opportunities, and challenges associated with liquid biopsy and pharmacogenomic (PGx) testing as precision therapy tools in the management of EGFR mutant and resistant lung cancers. Liquid biopsy could play a potential role in selection of precise tyrosine kinase inhibitor (TKI) therapies during different phases of lung cancer treatment. This selection will be based on the driver EGFR mutational status, as well as monitoring the development of potential EGFR mutations arising during or after TKIs treatment, since some of these new mutations may be druggable targets for alternative TKIs. Several studies have identified the utility of liquid biopsy in the identification of EGFR driver and acquired resistance with good sensitivities for various blood-based biomarkers. With a plethora of sequencing technologies and platforms available currently, further evaluations using randomized controlled trials (RCTs) in multicentric, multiethnic and larger patient cohorts could enable optimization of liquid-based assays for the detection of EGFR mutations, and support testing of CYP450 enzymes and drug transporter polymorphisms to guide precise dosing of EGFR TKIs.

Pharmacokinetics of edoxaban in EGFR-mutated non-small cell lung cancer patients with venous thromboembolism

BACKGROUND

The risk of venous thromboembolism (VTE) is increased 7-fold in patients with cancer than in those without. Low-molecular-weight heparin is the standard treatment for cancer-associated VTE. Direct oral anticoagulants (DOACs) are not inferior to low-molecular-weight heparin with respect to the general outcome of recurrent VTE. Warfarin is associated with a risk of bleeding when used in combination with gefitinib or erlotinib which are epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs). It is unclear, however, whether combination treatments with EGFR-TKIs and DOACs pose the same risk. We aimed to identify anticancer drugs and anticoagulants that can be used safely in combination, as accompanying research to an observational study on VTE incidence rates in lung cancer patients (Rising-VTE/NEJ037 study).

METHODS

Twelve patients receiving EFGR-TKI monotherapy and VTE treatment were enrolled. Blood samples were collected in time series after the first dose of edoxaban, and further samples were collected within 8-15 days after administering EGFR-TKIs. The pharmacokinetics (PK) of edoxaban were analyzed using a non-compartmental model.

RESULTS

Edoxaban concentrations (30 mg once daily) were measured in eight patients. PK analyses showed no significant differences before and after co-administration of EGFR-TKIs (gefitinib, erlotinib, and afatinib).

CONCLUSIONS

Our findings indicate that the PK of edoxaban was not considerably affected by co-administration of EGFR-TKIs (gefitinib, erlotinib, and afatinib).

Investigation of Biomarkers and Handling Strategy of Erlotinib-Induced Skin Rash in Rats

Skin rash is a common adverse event associated with erlotinib therapy. In severe conditions, the rash could affect patients' QOL. If the rash occurrence can be predicted, erlotinib treatment failures can be prevented. We designed an in vivo study that applied erlotinib regimens resembling its clinical application to evaluate possible erlotinib-induced skin rash biomarkers for humans and simultaneously observe the effects of erlotinib discontinuation, followed with or without dose reduction, on rash development. Rats were divided into four groups: placebo, constant (erlotinib 35 mg/kg on d1-d21), intermittent (erlotinib 70 mg/kg on d1-d7 and d15-d21), and mimic (erlotinib 70 mg/kg on d1-d7 and erlotinib 35 mg/kg on d15-d21). Blood sampling was performed on d1, d8, d15, and d22. The samples were used to measure erlotinib concentrations, the level of hepatic and renal function markers, immune cell percentages, and immune cells' CD45 expression levels. Erlotinib 70 mg/kg generated high mean circulating erlotinib concentrations (>1800 ng/mL) that led to severe rashes. Erlotinib dose reduction following rash occurrence reduced circulating erlotinib concentration and rash severity. After the treatment, the escalation of neutrophil percentages and reduction of neutrophils' CD45 expression levels were observed, which were significantly correlated with the rash occurrence. This study is the first to show that erlotinib-induced skin rash may be affected by the reduction of neutrophils' CD45 expression levels, and this is a valuable finding to elucidate the erlotinib-induced skin rash formation mechanism.

Inhibition and induction of CYP enzymes in humans: an update

The cytochrome P450 (CYP) enzyme family is the most important enzyme system catalyzing the phase 1 metabolism of pharmaceuticals and other xenobiotics such as herbal remedies and toxic compounds in the environment. The inhibition and induction of CYPs are major mechanisms causing pharmacokinetic drug–drug interactions. This review presents a comprehensive update on the inhibitors and inducers of the specific CYP enzymes in humans. The focus is on the more recent human in vitro and in vivo findings since the publication of our previous review on this topic in 2008. In addition to the general presentation of inhibitory drugs and inducers of human CYP enzymes by drugs, herbal remedies, and toxic compounds, an in-depth view on tyrosine-kinase inhibitors and antiretroviral HIV medications as victims and perpetrators of drug–drug interactions is provided as examples of the current trends in the field. Also, a concise overview of the mechanisms of CYP induction is presented to aid the understanding of the induction phenomena.

FDA- and EMA-Approved Tyrosine Kinase Inhibitors in Advanced EGFR-Mutated Non-Small Cell Lung Cancer: Safety, Tolerability, Plasma Concentration Monitoring, and Management

Non-small-cell lung cancer (NSCLC) is the most common form of primary lung cancer. The discovery of several oncogenic driver mutations in patients with NSCLC has allowed the development of personalized treatments based on these specific molecular alterations, in particular in the tyrosine kinase (TK) domain of the epidermal growth factor receptor (EGFR) gene. Gefitinib, erlotinib, afatinib, and osimertinib are TK inhibitors (TKIs) that specifically target EGFR and are currently approved by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA) as first line treatment for sensitive EGFR-mutant patients. However, these four drugs are associated with severe adverse events (AEs) that can significantly impact patient health-related quality of life and patient monitoring. EGFR-TKIs are commonly used together with other types of medication that can substantially interact. Here, we review approaches used for the management of TKI-AEs in patients with advanced NSCLC to promote the benefits of treatments and minimize the risk of TKI treatment discontinuation. We also consider potential TKI–drug interactions and discuss the usefulness of plasma concentration monitoring TKIs based on chromatographic and mass spectrometry approaches to guide clinical decision-making. Adjusting the most appropriate therapeutic strategies and drug doses may improve the performance therapy and prognosis of patients with advanced EGFR-mutated NSCLC.

Erlotinib treatment induces cytochrome P450 3A activity in non-small cell lung cancer patients

AIMS

Erlotinib is a tyrosine kinase inhibitor used in the treatment of non-small cell lung cancer highly metabolized by the cytochrome P450 (CYP) 3A. Hence, CYP3A4 activity might be a useful predictor of erlotinib pharmacokinetics in personalized medicine. The effect of erlotinib on CYP3A activity was therefore studied in non-small cell lung cancer patients.

METHODS

The study included 32 patients scheduled for erlotinib monotherapy. CYP3A activity was assessed using quinine as a probe before and during erlotinib treatment. Plasma from blood samples drawn 16 hours post quinine administration were analysed using HPLC with fluorescence detection to determine the quinine/3-OH-quinine ratio.

RESULTS

Matched samples, available from 13 patients, showed an induction of CYP3A activity (P = 0.003, Wilcoxon's signed rank test) after 2 months of treatment. The quinine/3-OH-quinine ratio decreased from 20.2 (± 13.4) at baseline to 11.0 (± 4.34). Single-point samples, available from 19 patients, supported the decrease in ratio (P = 0.007, Mann-Whitney U-test). Generally, females had a higher CYP3A activity both at baseline and after two months of treatment. Statistical analysis by gender also showed significant increase in CYP3A activity (males, n = 10, P = 0.001, and females, n = 22, P = 0.001).

CONCLUSIONS

An induction of CYP3A activity was observed after 2 months of erlotinib treatment which was also seen when subdividing based on gender. It could be important to take this into consideration for patients co-administering other CYP3A-metabolizing drugs during erlotinib treatment and also makes it difficult to use baseline CYP3A activity to predict erlotinib pharmacokinetics.