Beyond Osimertinib: The Development of Third-Generation EGFR Tyrosine Kinase Inhibitors For Advanced EGFR+ NSCLC

Design, preparation and biological evaluation of new Rociletinib-inspired analogs as irreversible EGFR inhibitors to treat non-small-cell-lung cancer

Epidermal growth factor receptor (EGFR) kinase has been implicated in the uncontrolled cell growth associated with non-small cell lung cancer (NSCLC). This has prompted the development of 3 generations of EGFR inhibitors over the last 2 decades due to the rapid development of drug resistance issues caused by clinical mutations, including T790M, L858R and the double mutant T790M & L858R. In this work we report the design, preparation and biological assessment of new irreversible 2,4-diaminopyrimidine-based inhibitors of EGFR kinase. Twenty new compounds have been prepared and evaluated which incorporate a range of electrophilic moieties. These include acrylamide, 2-chloroacetamide and (2E)-3-phenylprop-2-enamide, to allow reaction with residue Cys797. In addition, more polar groups have been incorporated to provide a better balance of physical properties than clinical candidate Rociletinib. Inhibitory activities against EGFR wildtype (WT) and EGFR T790M & L858R have been evaluated along with cytotoxicity against EGFR-overexpressing (A549, A431) and normal cell lines (HepG2). Selectivity against JAK3 kinase as well as physicochemical properties determination (logD7.4 and phosphate buffer solubility) have been used to profile the compounds. We have identified 20, 21 and 23 as potent mutant EGFR inhibitors (≤20 nM), with comparable or better selectivity over WT EGFR, and lower activity at JAK3, than Osimertinib or Rociletinib. Compounds 21 displayed the best combination of EGFR mutant activity, JAK3 selectivity, cellular activity and physicochemical properties. Finally, kinetic studies on 21 were performed, confirming a covalent mechanism of action at EGFR.

Receptor Pharmacogenomics: Deciphering Genetic Influence on Drug Response

The paradigm "one drug fits all" or "one dose fits all" will soon be challenged by pharmacogenetics research and application. Drug response-efficacy or safety-depends on interindividual variability. The current clinical practice does not include genetic screening as a routine procedure and does not account for genetic variation. Patients with the same illness receive the same treatment, yielding different responses. Integrating pharmacogenomics in therapy would provide critical information about how a patient will respond to a certain drug. Worldwide, great efforts are being made to achieve a personalized therapy-based approach. Nevertheless, a global harmonized guideline is still needed. Plasma membrane proteins, like receptor tyrosine kinase (RTK) and G protein-coupled receptors (GPCRs), are ubiquitously expressed, being involved in a diverse array of physiopathological processes. Over 30% of drugs approved by the FDA target GPCRs, reflecting the importance of assessing the genetic variability among individuals who are treated with these drugs. Pharmacogenomics of transmembrane protein receptors is a dynamic field with profound implications for precision medicine. Understanding genetic variations in these receptors provides a framework for optimizing drug therapies, minimizing adverse reactions, and advancing the paradigm of personalized healthcare.

Screening of protein-based inhibitors for the intracellular domain of epidermal growth factor receptor by directed evolution using the yeast Gγ recruitment system

Protein-based therapeutics, including antibodies and antibody-like-proteins, have increasingly attracted attention due to their high specificity compared to small-molecular drugs. The Gγ recruitment system, one of the in vivo yeast two-hybrid systems for detecting protein-protein interactions, has been previously developed using yeast signal transduction machinery. In this study, we modified the Gγ recruitment system to screen the protein mutants that efficiently bind to the intracellular domain of the epidermal growth factor receptor L858R mutant (cytoEGFRL858R). Using the modified platform, we performed in vivo directed evolution for growth factor receptor-bound protein 2 (Grb2) and its truncated variant containing only the Src-homology 2 (SH2) domain, successfully identifying several mutants that more strongly bound to cytoEGFRL858R than their parental proteins. Some of them contained novel beneficial mutations (F108Y and Q144H) and specifically bound to the recombinant cytosolic phosphorylated EGFR in vitro, highlighting the utility of the evolutionary platform.

Reversing MET-Mediated Resistance in Oncogene-Driven NSCLC by MET-Activated Wnt Condensative Prodrug

The amplification of MET is a major cause of acquired resistance to targeted therapy in EGFR-mutant non-small-cell lung cancer (NSCLC), only to be temporarily restrained by the partial efficacy of MET inhibitors. This study reveals that the MET inhibitor has unexpectedly limited efficacy due to amplified MET triggering a strong positive feedback loop in the Wnt/β-catenin signaling pathway, allowing optimal functionality even when the MET pathway is suppressed again. To test this conjecture and specifically target the Wnt/β-catenin pathway, a cleverly designed Wnt condensative pro drug called WntSI is developed using reversible supramolecular self-assembly driven by liquidliquid phase separation (LLPS). This process involves a MET/pH-responsive peptide (Tyr-Pep) and a potent Wnt inhibitor known as CA. Upon recognition and phosphorylation of Tyr-Pep by over expressed MET in cells, it disrupts LLPS propensity and facilitates the disintegration of WntSI. Consequently,this enables it to suppress the carcinogenic effect mediated by β-catenin,effectively overcoming acquired resistance to EGFR-TKIs caused by MET amplification in both cell line-derived and patient-derived tumor xenograft (PDX) mouse models while maintaining exceptional biosecurity. This effective strategy not only suppresses the Wnt/β-catenin signaling pathway selectively, but also serves as an innovative example for pro-drug development through biologically responsive LLPS.

Signaling dynamics in coexisting monoclonal cell subpopulations unveil mechanisms of resistance to anti-cancer compounds

BACKGROUND

Tumor heterogeneity is a main contributor of resistance to anti-cancer targeted agents though it has proven difficult to study. Unfortunately, model systems to functionally characterize and mechanistically study dynamic responses to treatment across coexisting subpopulations of cancer cells remain a missing need in oncology.

METHODS

Using single cell cloning and expansion techniques, we established monoclonal cell subpopulations (MCPs) from a commercially available epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer cell line. We then used this model sensitivity to the EGFR inhibitor osimertinib across coexisting cell populations within the same tumor. Pathway-centered signaling dynamics associated with response to treatment and morphological characteristics of the MCPs were assessed using Reverse Phase Protein Microarray. Signaling nodes differentially activated in MCPs less sensitive to treatment were then pharmacologically inhibited to identify target signaling proteins putatively implicated in promoting drug resistance.

RESULTS

MCPs demonstrated highly heterogeneous sensitivities to osimertinib. Cell viability after treatment increased > 20% compared to the parental line in selected MCPs, whereas viability decreased by 75% in other MCPs. Reduced treatment response was detected in MCPs with higher proliferation rates, EGFR L858R expression, activation of EGFR binding partners and downstream signaling molecules, and expression of epithelial-to-mesenchymal transition markers. Levels of activation of EGFR binding partners and MCPs' proliferation rates were also associated with response to c-MET and IGFR inhibitors.

CONCLUSIONS

MCPs represent a suitable model system to characterize heterogeneous biomolecular behaviors in preclinical studies and identify and functionally test biological mechanisms associated with resistance to targeted therapeutics.

Benefit from Almonertinib after Osimertinib treat EGFR 19 exon deletion NSCLC induced Severe rash: a case report

Osimertinib, a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), has been recommended as a first-line treatment of EGFR-positive non-small cell lung cancer (NSCLC). Skin rash is one of the most common side effects of osimertinib, and can have an impact on patients' quality of life and follow-up. However, there are few reports on the safety and efficacy of switching therapy with osimertinib and the other three generations of TKIs. In this paper, we present a case of NSCLC with an EGFR exon 19 deletion (19del) and MET gene amplification who developed a severe rash after 2 months of treatment with osimertinib that did not recur after switching to replacement therapy with aumonertinib. Our findings indicate that aumonertinib is as effective as osimertinib in treating EGFR19del, while also exhibiting a lower occurrence of adverse skin reactions. This may result in an improved quality of life for patients.

Impact of PD-L1 Expression on the Overall Survival of Caucasian Patients with Advanced EGFR-Mutant NSCLC Treated with Frontline Osimertinib

BACKGROUND

The treatment of advanced non-small cell lung cancer (NSCLC) harboring an oncogenic epidermal growth factor receptor mutation (EGFRm) is currently based on osimertinib, a third-generation tyrosine kinase inhibitor (TKI). High Programmed death ligand 1 (PD-L1) expression ≥ 50% demonstrated to be a negative prognostic factor, mostly among Asian populations treated with 1st/2nd generation TKI.

OBJECTIVE

We investigated the impact of PD-L1 expression on the progression free survival (PFS) and overall survival (OS) within a cohort of patients receiving osimertinib as first-line treatment.

METHODS

Our bi-centre French retrospective study included all newly diagnosed patients with an advanced EGFRm (common and uncommon) NSCLC, between May 2018 and November 2022, treated with osimertinib. The primary endpoint was OS according to tumor proportion score PD-L1 expression (low/intermediate < 50% vs high ≥ 50%). Survival analyses were performed using Kaplan-Meier method and Cox model for adjusted multivariate analysis.

RESULTS

Of 96 patients, median age was 71 (IQR 62-76), 70 were women (72.9%), 81 had a performance status (PS) 0-1 (84.3%). Median follow-up was 22.6 months (95% CI 20.5-24.7). Twenty patients (20.8%) had high PD-L1 expression ≥ 50%. No significant differences in baseline characteristics were observed based on PD-L1 status. Patients with PD-L1 ≥ 50% had significant shorter PFS and OS than those with PD-L1 < 50%, respectively 9.3 vs 17.5 months (p = 0.044 months) and 14.3 vs 26.0 months (p = 0.025). Multivariable adjustment for baseline characteristics found that PS ≥ 2 (HR 2.79, 95% CI 1.12-6.93, p = 0.027), PD-L1 ≥ 50% (HR 2.61, 95% CI 1.31 to 5.22, p = 0.007) and uncommon EGFR mutation (HR 4.59, 95% CI 1.95-10.80, p = <0.001) were associated with a shorter OS. Brain metastases at diagnosis and age ≥ 65 were not, respectively HR 1.66 (95% CI 0.90-3.06, p = 0.11) and HR 0.95 (95% CI 0.50-1.80, p=0.9).

CONCLUSIONS

Our study found that PD-L1 expression ≥ 50% was associated with a shorter OS in EGFRm NSCLC patients treated with first line osimertinib. Further research is warranted to understand the underlying molecular and cellular mechanisms of this correlation.

Emerging paradigms and recent progress in targeting ErbB in cancers

The epidermal growth factor receptor (EGFR) family is a class of transmembrane proteins, highly regarded as anticancer targets due to their pivotal role in various malignancies. Standard cancer treatments targeting the ErbB receptors include tyrosine kinase inhibitors (TKIs) and monoclonal antibodies (mAbs). Despite their substantial survival benefits, the achievement of curative outcomes is hindered by acquired resistance. Recent advancements in anti-ErbB approaches, such as inhibitory peptides, nanobodies, targeted-protein degradation strategies, and bispecific antibodies (BsAbs), aim to overcome such resistance. More recently, emerging insights into the cell surface interactome of the ErbB family open new avenues for modulating ErbB signaling by targeting specific domains of ErbB partners. Here, we review recent progress in ErbB targeting and elucidate emerging paradigms that underscore the significance of EGF domain-containing proteins (EDCPs) as new ErbB-targeting pathways.

Non-small cell lung cancer: an update on emerging EGFR-targeted therapies

INTRODUCTION

Current research in EGFR-mutated NSCLC focuses on the management of drug resistance and uncommon mutations, as well as on the opportunity to extend targeted therapies' field of action to earlier stages of disease.

AREAS COVERED

We conducted a review analyzing literature from the PubMed database with the aim to describe the current state of art in the management of EGFR-mutated NSCLC, but also to explore new strategies under investigation. To this purpose, we collected recruiting phase II-III trials registered on Clinicaltrials.govand conducted on EGFR-mutated NSCLC both in early and advanced stage.

EXPERT OPINION

With this review, we want to provide an exhaustive overview of current and new potential treatments in EGFR-mutated NSCLC, with emphasis on the most promising newly investigated strategies, such as association therapies in the first-line setting involving EGFR-TKIs and chemotherapy (FLAURA2) or drugs targeting different driver pathways (MARIPOSA). We also aimed at unearthing challenges to achieve in this field, specifically the need to fully exploit already available compounds while developing new ones, the management of new emerging toxicities and the necessity to improve our biological understanding of the disease to design trials with a solid scientific rationale and to allow treatment personalization such in case of uncommon mutations.

Identification of EGFR R776H germline mutations in a patient with multifocal lung adenocarcinoma: A case report and literature review

The advancement of molecular pathology techniques has led to the discovery of rare EGFR mutations for targeted therapy in lung cancer. Additionally, a substantial body of evidence indicates a connection between the development of lung cancer and genetic variations in the EGFR gene. Here, we present a case report of a patient with multifocal lung adenocarcinoma who possessed a rare germline mutation, EGFR R776H. An investigation into the family history of the patient exposed the notable incidence of lung adenocarcinoma, indicating a plausible genetic vulnerability to the ailment. To be specific, the patient's older brother and sister both suffered from lung cancer, which underlines the hereditary predisposition. Furthermore, it should be noted that the patient's daughter has inherited the germline mutation and also presented with multiple lung ground-glass nodules, emphasizing the clinical importance of this genetic variation. Following the lobectomy, the patient received treatment with almonertinib, a third-generation EGFR tyrosine kinase inhibitor (TKI), and at the latest follow-up, the patient has achieved partial remission. This case highlights the significance of taking into account germline possibilities when multiple lesions carry the same mutation. It stresses the importance of acquiring a comprehensive family history and performing genetic testing on leukocytes. Moreover, for the infrequent EGFR R776H mutation, third generation EGFR-TKIs may be a viable option.

Chemical Scaffolds for the Clinical Development of Mutant-Selective and Reversible Fourth-Generation EGFR-TKIs in NSCLC

In nonsmall cell lung cancer (NSCLC), as well as in other tumors, the targeted therapy is mainly represented by tyrosine kinase inhibitors (TKIs), small molecules able to target oncogenic driver alterations affecting the gene encoding the epidermal growth factor receptor (EGFR). Up to now, several different TKIs have been developed. However, cancer cells showed an incredible adaptive tumor response to the inhibition of the sequentially mutated EGFR (EGFRM+), triggering the need to explore novel pharmacochemical strategies. This Review summarizes the recent efforts in the development of new reversible next-generation EGFR TKIs to fight the resistance against T790M and C797S mutations. Specifically, after giving an overview of the role of the EGFR's signaling pathways in cancer progression, we are going to discuss the most relevant approved drugs and drug candidates in terms of chemical structure, binding modalities, and their potency and selectivity against the mutated EGFR over the wild-type form. This could provide important guidelines and rationale for the discovery and iterative development of new drugs.

Efficacy of befotertinib in non-small cell lung cancer harboring uncommon compound EGFR mutations G719X and S768I: a case report

The discovery of epidermal growth factor receptor (EGFR) somatic mutations and the availability of tyrosine kinase inhibitors (TKIs) as targeted therapies have transformed the treatment landscape for advanced non-small cell lung cancer (NSCLC). p.G719X and p.S768I mutations, often present in the form of complex mutations, are considered rare. This study firstly reported the treatment outcome of a locally advanced unresectable NSCLC patient with a rare complex EGFR p.G719X/p.S768I mutations who received befotertinib. After treatment, the patient achieved partial response (PR), and no severe adverse events were observed. This case report supported befotertinib as a promising treatment option for advanced NSCLC patients with the rare p.G719X/p.S768I complex mutations.

Deterministic reprogramming and signaling activation following targeted therapy in non-small cell lung cancer driven by mutations or oncogenic fusions

INTRODUCTION

Targeted therapy is used to treat lung adenocarcinoma caused by epidermal growth factor receptor (EGFR) mutations in the tyrosine kinase domain and rare subtypes (<5%) of non-small cell lung cancer. These subtypes include fusion oncoproteins like anaplastic lymphoma kinase (ALK), ROS1, rearranged during transfection (RET), and other receptor tyrosine kinases (RTKs). The use of diverse selective oral inhibitors, including those targeting rat sarcoma viral oncogene homolog (KRAS) mutations, has significantly improved clinical responses, extending progression-free and overall survival.

AREAS COVERED

Resistance remains a critical issue in lung adenocarcinoma, notably in EGFR mutant, echinoderm microtubule associated protein-like 4 (EML4)-ALK fusion, and KRAS mutant tumors, often associated with epithelial-to-mesenchymal transition (EMT).

EXPERT OPINION

Despite advancements in next generation EGFR inhibitors and EML4-ALK therapies with enhanced brain penetrance and identifying resistance mutations, overcoming resistance has not been abated. Various strategies are being explored to overcome this issue to achieve prolonged cancer remission and delay resistance. Targeting yes-associated protein (YAP) and the mechanisms associated with YAP activation through Hippo-dependent or independent pathways, is desirable. Additionally, the exploration of liquid-liquid phase separation in fusion oncoproteins forming condensates in the cytoplasm for oncogenic signaling is a promising field for the development of new treatments.

Radiation pneumonitis after concurrent aumolertinib and thoracic radiotherapy in EGFR-mutant non-small cell lung cancer patients

BACKGROUND

The superior efficacy of concurrent thoracic radiotherapy (TRT) and epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) has been proven in locally advanced and advanced non-small cell lung cancer (NSCLC) patients with EGFR mutations. However, the high incidence of radiation pneumonitis (RP) reduced by concurrent TRT and TKIs has attracted widespread attention. Thus, this study was designed to investigate the rate and risk factors for RP in EGFR-positive NSCLC patients simultaneously treated with aumolertinib and TRT.

METHODS

We retrospectively evaluated stage IIIA-IVB NSCLC patients treated with concurrent aumolertinib and TRT between May 2020 and December 2022 at Shandong Cancer Hospital and Institute, Shandong, China. RP was diagnosed by two senior radiologists and then graded from 1 to 5 according to the Common Terminology Criteria for Adverse Events v5.0. All risk factors were evaluated by univariate and multivariate logistic regression analyses.

RESULTS

A total of 49 patients were included, the incidence of grade ≥ 2 RP was 42.9%. Grade 2 and 3 RP were observed in 28.6% and 14.3% of patients, respectively. Grade 4 to 5 RP were not observed. the gross total volume (GTV) ≥ 21 ml and ipsilateral lung V20 ≥ 25% were risk factors for RP. The median progression-free survival (PFS) in the first-line therapy group and second-line therapy group were 23.5 months and 17.2 months, respectively (p = 0.10).

CONCLUSIONS

Better local control is achieved with concurrent TRT and aumolertinib, and special attention should be given to controlling ipsilateral lung V20 and GTV to reduce the risk of RP.

Safety, Tolerability, Pharmacokinetics, and Preliminary Efficacy of YK-029A in Treatment-Naive Patients With Advanced NSCLC Harboring EGFR Exon 20 Insertion Mutations: A Phase 1 Trial

INTRODUCTION

Treatment options for treatment-naive patients with advanced NSCLC harboring EGFR exon 20 insertion (ex20ins) mutations are limited. This study evaluated the safety, tolerability, and pharmacokinetics of YK-029A, a third-generation EGFR tyrosine kinase inhibitor, and the preliminary efficacy of YK-029A in treatment-naive patients with EGFR ex20ins mutation.

METHODS

This multicenter, dose-escalation, and dose-expansion phase 1 clinical trial enrolled patients with NSCLC harboring EGFR mutations. During the dose-escalation phase, YK-029A was orally administered using the traditional 3+3 principle at 50, 100, 150, 200, and 250 mg/d. In the dose-expansion phase, treatment-naive patients with EGFR ex20ins mutations were enrolled and administered YK-029A 200 mg/d. The primary end point was safety and tolerability.

RESULTS

The safety analysis included 108 patients. No dose-limiting toxicity was observed, and the maximum tolerated dose was not reached. The most common treatment-emergent adverse events were anemia (50.9%), diarrhea (49.1%), and rash (34.3%). There was minimal drug accumulation after multiple doses. A total of 28 treatment-naive patients with EGFR ex20ins mutations were enrolled in the dose-expansion and 26 were included in the efficacy analysis. According to the independent review committee evaluation, the objective response rate was 73.1% (95% confidence interval: 52.21%-88.43%), and the disease control rate was 92.3% (95% confidence interval: 74.87%-99.05%).

CONCLUSIONS

YK-029A was found to have manageable safety and be tolerable in patients with NSCLC harboring EGFR mutations and have promising antitumor activity in untreated patients with EGFR ex20ins mutations.

Targeting EGFR allosteric site with marine-natural products of Clathria Sp.: A computational approach

The EGFR-C797S resistance mutation to third-generation drugs has been overcome by fourth-generation inhibitors, allosteric inhibitors, namely EAI045 and has reached phase 3 clinical trials, so the Allosteric Site is currently an attractive target for development. In this study, researchers are interested in knowing the activity of metabolite compounds from marine natural ingredients Clathria Sp. against the Allosteric Site of EGFR computationally. The methods used include molecular docking using Autodock4 software and Molecular Dynamics simulation performed using GROMACS software. The research began with the preparation of metabolite samples from Clathria Sp. through the KnapSack database site and the preparation of EGFR receptors that have been complexed with allosteric inhibitors, namely proteins with PDB code 5D41. Each compound was docked to the Allosteric Site of the natural ligand and then molecular dynamics simulations were performed on the compound with the best docking energy compared to the natural ligand. From the docking results, the Clathrin_A compound showed the lowest binding energy compared to other metabolites, and the value was close to the natural ligand. Then from the molecular dynamics results, the clathrin_A compound shows good stability and resembles the natural ligand, which is analyzed through RMSD, RMSF, SASA, Rg, and PCA, and shows the binding free energy from MMPBSA analysis which is close to the natural ligand. It can be concluded, Clathrin_A compound has potential as an allosteric inhibitor.

Pyrrolo[2,3-D]Pyrimidines as EGFR and VEGFR Kinase Inhibitors: A Comprehensive SAR Review

Tyrosine kinases are implicated in a wide array of cellular physiological processes, including cell signaling. The discovery of the BCR-ABL tyrosine kinase inhibitor imatinib and its FDA approval in 2001 paved the way for the development of small molecule chemical entities of diverse structural backgrounds as tyrosine kinase inhibitors for the treatment of various ailments. Two of the most prominent tyrosine kinases as drug targets are the epidermal growth factor receptor (EGFR) and the vascular endothelial growth factor receptor (VEGFR), as evidenced by the clinical success of their many inhibitors in the drug market. Among several other physiological roles, EGFR regulates epithelial tissue development and homeostasis, while VEGFR regulates tumor-induced angiogenesis. The pyrrolo[2,3-d]pyrimidine nucleus represents a deaza-isostere of adenine, the nitrogenous base of ATP. The recent introduction of many pyrrolo[2,3-d]pyrimidines to the drug market as tyrosine kinase inhibitors makes them a hot topic in the medicinal chemistry research area at the present time. This review article comprehensively sheds light on the structure-activity relationship (SAR) of pyrrolo[2,3-d]pyrimidines as EGFR and VEGFR tyrosine kinase inhibitors, aiming to provide help medicinal chemists in the design of future pyrrolopyrimidine kinase inhibitors.

Trends and prescribing patterns of oral anti-neoplastic drugs: a retrospective longitudinal study

Background

Cancer as a global public health problem, imposes a heavy disease burden. With the rapid development of oral anti-neoplastic drugs, there has been a paradigm shift in the treatment of cancer from intravenous to oral administration.

Objective

This study was conducted to investigate the trends and prescribing patterns of oral anti-neoplastic drugs in an academic tertiary hospital in China.

Methods

A single-center and retrospective analysis was performed based on the prescriptions of outpatients treated with oral anti-neoplastic drugs from 2017 to 2022. Yearly prescriptions and expenditure were calculated according to their pharmacological classes, and trends were further analyzed. Defined daily doses (DDDs) and defined daily cost (DDC) of oral targeted anti-neoplastic drugs were also determined.

Results

Both the number of prescriptions and expenditure of oral anti-neoplastic drugs increased progressively. There was a significant upward trend in the number and proportion of prescriptions for the older adult group, male group, and patients with gynecologic/genitourinary and respiratory cancer. Hormonal therapy agents accounted for the highest proportion of prescriptions, and letrozole was initially the most frequently prescribed drug. The number of DDDs of total oral targeted anti-neoplastic drugs showed a continuously ascending trend, primarily driven by the usage of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) and BCR-ABL TKIs.

Conclusion

The prescriptions and expenditure of oral anti-neoplastic drugs, and the number of DDDs of oral targeted anti-neoplastic drugs all showed a progressively ascending trend. Further studies are needed to evaluate the long-term health and financial outcomes, and the factors influencing these prescribing patterns.

20 years since the approval of first EGFR-TKI, gefitinib: Insight and foresight

Epidermal growth factor receptor (EGFR) actively involves in modulation of various cancer progression related mechanisms including angiogenesis, differentiation and migration. Therefore, targeting EGFR has surfaced as a prominent approach for the treatment of several types of cancers, including non-small cell lung cancer (NSCLC), pancreatic cancer, glioblastoma. Various first, second and third generation of EGFR tyrosine kinase inhibitors (EGFR-TKIs) have demonstrated effectiveness as an anti-cancer therapeutics. However, rapid development of drug resistance and mutations still remains a major challenge for the EGFR-TKIs therapy. Overcoming from intrinsic and acquired resistance caused by EGFR mutations warrants the further exploration of alternative strategies and discovery of novel inhibitors. In this review, we delve into the breakthrough discoveries have been made in previous 20 years, and discuss the currently ongoing efforts aimed to circumvent the chemo-resistance. We also highlight the new challenges, limitations and future directions for the development of improved therapeutic approaches such as fourth-generation EGFR-TKIs, peptides, nanobodies, PROTACs etc.

Discovery of YS-363 as a highly potent, selective, and orally efficacious EGFR inhibitor

The Epidermal Growth Factor Receptor (EGFR) tyrosine kinase inhibitors (TKIs) are the standard first-line therapy for EGFR-mutated NSCLC. However, long-term clinical treatment often leads to acquired drug resistance, making NSCLC refractory. Therefore, it is essential to design new EGFR inhibitors as potential drugs against NSCLC. This study reports on a novel quinazoline-based compound called YS-363 that acts as a new EGFR inhibitor. YS-363 demonstrated potent inhibition against both wild-type and L858R mutant forms of EGFR with IC50 values of 0.96 nM and 0.67 nM, respectively. Additionally, YS-363 had a reversible inhibitory effect on cellular EGFR signaling, had excellent inhibitory activity on cell proliferation and migration, and induced G0/G1 cell cycle arrest and apoptosis. In xenograft models dependent on EGFR signaling, oral administration of YS-363 substantially suppressed tumor growth by inhibiting this pathway. In summary, YS-363 is a promising selective reversible inhibitor with a novel quinazoline scaffold that can potentially develop more effective anti-lung cancer agents targeting EGFR in patients who have developed resistance to current therapies such as TKIs like gefitinib or erlotinib.

Intrinsic Resistance to Osimertinib in EGFR Mutated NSCLC Cell Lines Induced by Alteration in Cell-Cycle Regulators

BACKGROUND

Cell-cycle regulators are mutated in approximately 40% of all cancer types and have already been linked to worse outcomes in non-small cell lung cancer adenocarcinomas treated with osimertinib. However, their exact role in osimertinib resistance has not been elucidated.

OBJECTIVE

In this study, we aimed to evaluate how the CDK4/6-Rb axis may affect the sensitivity to osimertinib.

METHODS

We genetically increased the level of CCND1 (Cyclin D1) and reduced the levels of CDKN2A (p16) in two different adenocarcinoma cell lines, PC9 and HCC827. We also retrospectively evaluated the outcome of patients with epidermal growth factor receptor-mutated advanced non-small cell lung cancer depending on their level of Cyclin D1 and p16.

RESULTS

The modified clones showed higher proliferative capacity, modifications in cell-cycle phases, and higher migratory capacity than the parental cells. Cyclin D1-overexpressing clones were highly resistant to acute osimertinib treatment. CDKN2A knockdown conferred intrinsic resistance as well, although a longer time was required for adaption to the drug. In both cases, the resistant phenotype was epidermal growth factor receptor independent and associated with a higher level of Rb phosphorylation, which was unaffected by osimertinib treatment. Blocking the phosphorylation of Rb using abemaciclib, a CDK4/6 inhibitor, exerted an additive effect with osimertinib, increasing sensitivity to this drug and reverting the intrinsic resistant phenotype. In a group of 32 patients with epidermal growth factor receptor-mutated advanced non-small cell lung cancer, assessed for Cyclin D1 and p16 expression, we found that the p16-deleted group presented a lower overall response rate compared with the control group.

CONCLUSIONS

We conclude that perturbation in cell-cycle regulators leads to intrinsic osimertinib resistance and worse patient outcomes.

In vivo evaluation of the pharmacokinetic interactions between almonertinib and rivaroxaban, almonertinib and apixaban

Background: Almonertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), is commonly used as a first-line treatment for non-small cell lung cancer (NSCLC) patients with EGFR T790M mutations. Rivaroxaban and apixaban are a selective, direct factor Xa inhibitor used to treat venous thromboembolism (VTE), which is a frequent complication of NSCLC. Rivaroxaban and apixaban are substrates of CYP3A4, P-gp and BCRP, whereas almonertinib is an inhibitor of P-gp and BCRP. Rivaroxaban or apixaban are often prescribed together with almonertinib in NSCLC patients, but clear information on pharmacokinetic drug interaction is lacking. Therefore, this study aimed to unravel the extent of interactions between almonertinib-rivaroxaban and almonertinib apixaban in rats, and whether the pharmacokinetic interaction can be mitigated by rivaroxaban and apixaban dose adjustment. Methods: Rats were divided into ten groups (n = 6) that received rivaroxaban (2 mg/kg) (group 1), apixaban (0.5 mg/kg) (group 2), almonertinib (15 mg/kg) (group 3, group 4), almonertinib with rivaroxaban (2 mg/kg) (group 5), almonertinib with rivaroxaban (1 mg/kg) (group 6), almonertinib with apixaban (0.5 mg/kg) (group 7), almonertinib with apixaban (0.25 mg/kg) (group 8), rivaroxaban (2 mg/kg) with almonertinib (group 9), apixaban (0.5 mg/kg) with almonertinib (group 10). The concentrations of drugs were determined by an ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The levels of messenger RNA were determined using quantitative real-time polymerase chain reaction (qRT-PCR). Results and Discussion: The results indicate that almonertinib increased the Cmax and AUC0-t of 2 mg/kg rivaroxaban by 3.30 and 3.60-fold, 1 mg/kg rivaroxaban by 1.28 and 1.90-fold. Almonertinib increased the Cmax and AUC0-t of 0.5 mg/kg apixaban by 2.69 and 2.87-fold, 0.25 mg/kg apixaban by 2.19 and 2.06-fold. In addition, rivaroxaban also increased systemic exposure to almonertinib. The results of qRT-PCR showed that almonertinib reduced the expression of Cyp3a1 in liver and intestine, and Abcb1a, Abcg2 in intestine and kidney. The pharmacokinetic results suggest that it is important to take special care of the interactions of these drugs in clinical applications.

Effect of Food on the Pharmacokinetics of Limertinib (ASK120067) and its Main Metabolite in Healthy Chinese Volunteers

Limertinib (ASK120067) is a newly developed third-generation epidermal growth factor receptor tyrosine kinase inhibitor. This phase I, open-label, 2-period crossover study was conducted to evaluate the effect of food on the pharmacokinetics (PK) of limertinib and its active metabolite CCB4580030 in Chinese healthy volunteers (HVs). HVs were randomly assigned (1:1) to receive a single dose of limertinib (160 mg) under the fasted state in period 1 and fed condition in period 2, or vice versa. Twenty-four HVs were enrolled, and 20 HVs completed both study periods. PK were assessed before dosing and ≤72 hours after dosing. PK parameters were analyzed by a noncompartmental method. Limertinib was absorbed faster in the fasted state compared with the fed state. The geometric mean ratios (fed/fast) of maximum concentration, area under the plasma concentration-time curve from time 0 to the last quantifiable concentration, and area under the plasma concentration-time curve from time 0 to infinity for ASK120067 were 145.5%, 145.4%, and 141.9%, respectively. Geometric mean ratios of the PK parameters of CCB4580030 were >125.00% and 90% confidence intervals were outside the preset bioequivalent range. Safety profiles were similar in both prandial states, and limertinib was well tolerated. Food reduced the rate and increased the extent of limertinib absorption following oral administration. Whether limertinib can be administered regardless of prandial state in patients warrants further investigation of efficacy and safety.

Befotertinib: First Approval

Befotertinib (Surmana®) is an orally administered, highly selective, third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) being developed by Betta Pharmaceuticals and InventisBio for the treatment of non-small cell lung cancer (NSCLC). In May 2023, befotertinib was approved in China for the second-line treatment of patients with locally advanced or metastatic NSCLC who have received EGFR TKI therapy and have disease progression with positive EGFR T790M mutation. Befotertinib is under regulatory review for the first-line treatment of NSCLC in China. Clinical studies assessing befotertinib as an adjuvant therapy after surgery for early EGFR-mutant NSCLC (phase III) and in combination with icotinib for advanced or metastatic EGFR-mutant NSCLC (phase II) are currently underway in China. This article summarizes the milestones in the development of befotertinib leading to this first approval for the second-line treatment of EGFR T790M-mutated locally advanced or metastatic NSCLC.

Recent advances in targeting the "undruggable" proteins: from drug discovery to clinical trials

Undruggable proteins are a class of proteins that are often characterized by large, complex structures or functions that are difficult to interfere with using conventional drug design strategies. Targeting such undruggable targets has been considered also a great opportunity for treatment of human diseases and has attracted substantial efforts in the field of medicine. Therefore, in this review, we focus on the recent development of drug discovery targeting "undruggable" proteins and their application in clinic. To make this review well organized, we discuss the design strategies targeting the undruggable proteins, including covalent regulation, allosteric inhibition, protein-protein/DNA interaction inhibition, targeted proteins regulation, nucleic acid-based approach, immunotherapy and others.

Management of diarrhea induced by EGFR-TKIs in advanced lung adenocarcinoma

The identification of Epidermal Growth Factor Receptor (EGFR) mutations in lung adenocarcinoma has facilitated the development of personalized medicine based on oncogenic drivers. EGFR-Tyrosine Kinase Inhibitors (TKIs) are part of the targeted therapy; they impede the phosphorylation of the intracellular tyrosine kinase component of EGFR and consequently block signal transduction pathways. These drugs inhibit the proliferation and survival of tumor cells, leading to long-term progression-free survival and overall survival. Diarrhea is one of the most frequent adverse events associated with EGFR-TKIs, affecting at least 18% of patients and reaching up to 95% in some cases. Diarrhea should be managed carefully given its association with important complications, treatment interruptions, and dose reductions. Moreover, nutritional status and quality of life (QoL) can deteriorate due to severe diarrhea. Changes in diet, such as increment of fiber, supplementation with glutamine, and use of probiotics, may contribute to a decrease in the incidence of diarrhea. Improving the control of diarrhea can provide a significant benefit to the QoL of patients.

Small molecule protein kinase inhibitors approved by regulatory agencies outside of the United States

Owing to genetic alterations and overexpression, the dysregulation of protein kinases plays a significant role in the pathogenesis of many autoimmune and neoplastic disorders and protein kinase antagonists have become an important drug target. Although the efficacy of imatinib in the treatment of chronic myelogenous leukemia in the United States in 2001 was the main driver of protein kinase inhibitor drug discovery, this was preceded by the approval of fasudil (a ROCK antagonist) in Japan in 1995 for the treatment of cerebral vasospasm. There are 21 small molecule protein kinase inhibitors that are approved in China, Japan, Europe, and South Korea that are not approved in the United Sates and 75 FDA-approved inhibitors in the United States. Of the 21 agents, eleven target receptor protein-tyrosine kinases, eight inhibit nonreceptor protein-tyrosine kinases, and two block protein-serine/threonine kinases. All 21 drugs are orally bioavailable or topically effective. Of the non-FDA approved drugs, sixteen are prescribed for the treatment of neoplastic diseases, three are directed toward inflammatory disorders, one is used for glaucoma, and fasudil is used in the management of vasospasm. The leading targets of kinase inhibitors approved by both international regulatory agencies and by the FDA are members of the EGFR family, the VEGFR family, and the JAK family. One-third of the 21 internationally approved drugs are not compliant with Lipinski's rule of five for orally bioavailable drugs. The rule of five relies on four parameters including molecular weight, number of hydrogen bond donors and acceptors, and the Log of the partition coefficient.

The Importance of the Pyrazole Scaffold in the Design of Protein Kinases Inhibitors as Targeted Anticancer Therapies

The altered activation or overexpression of protein kinases (PKs) is a major subject of research in oncology and their inhibition using small molecules, protein kinases inhibitors (PKI) is the best available option for the cure of cancer. The pyrazole ring is extensively employed in the field of medicinal chemistry and drug development strategies, playing a vital role as a fundamental framework in the structure of various PKIs. This scaffold holds major importance and is considered a privileged structure based on its synthetic accessibility, drug-like properties, and its versatile bioisosteric replacement function. It has proven to play a key role in many PKI, such as the inhibitors of Akt, Aurora kinases, MAPK, B-raf, JAK, Bcr-Abl, c-Met, PDGFR, FGFRT, and RET. Of the 74 small molecule PKI approved by the US FDA, 8 contain a pyrazole ring: Avapritinib, Asciminib, Crizotinib, Encorafenib, Erdafitinib, Pralsetinib, Pirtobrutinib, and Ruxolitinib. The focus of this review is on the importance of the unfused pyrazole ring within the clinically tested PKI and on the additional required elements of their chemical structures. Related important pyrazole fused scaffolds like indazole, pyrrolo[1,2-b]pyrazole, pyrazolo[4,3-b]pyridine, pyrazolo[1,5-a]pyrimidine, or pyrazolo[3,4-d]pyrimidine are beyond the subject of this work.

Epidermal Growth Factor Receptor T790M Mutation Testing in Non-Small Cell Lung Cancer: An International Collaborative Study to Assess Molecular EGFR T790M Testing in Liquid Biopsy

BACKGROUND

The detection of the EGFR T790M (T790M) mutation in non-small cell lung cancer (NSCLC) patients who progressed under treatment with first- or second-generation EGFR-tyrosine kinase inhibitors (TKIs) is important to offer a subsequent therapy with a third-generation EGFR-TKI. Liquid biopsy is a powerful tool to determine the T790M mutation status. Several liquid biopsy platforms with varying degrees of accuracy are available to test for T790M mutations, and sensitivities may differ among these methods.

METHODS

As no standard exists for the testing of T790M mutation in liquid biopsy, we performed a collaborative study to describe and compare the sensitivity of different in-house liquid biopsy platforms for the detection of the T790M mutation, EGFR exon 19 deletion (del19) and EGFR L858R mutation (L858R) across multiple participating laboratories in seven Central and Eastern European countries.

RESULTS

Of the 25 invited laboratories across Central and Eastern Europe, 21 centers participated and received 10 plasma samples spiked with cell-line DNA containing the T790M, del19, or L858R mutation in different concentrations. In-house PCR-based and NGS-based methods were used accordingly, and results were reported as in routine clinical practice. Two laboratories, which used the AmoyDx^® EGFR 29 Mutations Detection Kit (AmoyDx) with Cobas^® cfDNA Sample Preparation Kit and QX200 Droplet Digital PCR (ddPCR) with the QIAamp Circulating Nucleic Acid Kit identified all ten samples correctly. Cobas^® EGFR Mutation Test v2 (Cobas), the NGS methods, and the Idylla^TM detection method used in this study performed within the known sensitivity range of each detection method.

CONCLUSIONS

If a negative result was obtained from methods with lower sensitivity (e.g., Cobas), repeated liquid biopsy testing and/or tissue biopsy analysis should be performed whenever possible, to identify T790M-positive patients to allow them to receive the optimal second-line treatment with a third-generation EGFR TKI.

The next generation of EGFR inhibitors: a patenting perspective of PROTACs based EGFR degraders

INTRODUCTION

Abnormal expression of epidermal growth factor receptor (EGFR) contributes to tumor development, especially in non-small cell lung cancer (NSCLC). Although multiple inhibitors have been developed to target diverse EGFR mutations and several have been approved, the inevitable drug resistance and side effect remain a challenge, which motivates novel strategies. Proteolysis-targeting chimeras (PROTACs) have been gaining momentum for their potential as novel therapeutics for human diseases by triggering protein degradation. To date, various potent and specific EGFR PROTACs have been discovered and some of them have entered clinical trials.

AREAS COVERED

This review provides an overview of EGFR degraders in patents from 2016 to 2022. It provides an update of the discovery strategies, chemical structures, and molecular profiling of all available EGFR PROTACs. SciFinder, PubMed, Web of Science, EPO, and CNIPA databases were used for searching the literature and patents for EGFR PROTACs.

EXPERT OPINION

By employing the PROTAC technology, highly potent and selective EGFR degraders based on four generation EGFR inhibitors have been developed, which offer a new strategy to target EGFR mutations and overcome the drug resistance. Despite the satisfactory result in vitro and in vivo studies, their therapeutic value awaits more rigorous preclinical testing and clinical investigation.

Insights into fourth generation selective inhibitors of (C797S) EGFR mutation combating non-small cell lung cancer resistance: a critical review

Lung cancer is the second most common cause of morbidity and mortality among cancer types worldwide, with non-small cell lung cancer (NSCLC) representing the majority of most cases. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) are among the most commonly used targeted therapy to treat NSCLC. Recent years have seen the evaluation of many synthetic EGFR TKIs, most of which showed therapeutic activity in pertinent models and were classified as first, second, and third-generation. The latest studies have concluded that their efficacy was also compromised by additional acquired mutations, including C797S. Because second- and third-generation EGFR TKIs are irreversible inhibitors, they are ineffective against C797S containing EGFR triple mutations (Del19/T790M/C797S and L858R/T790M/C797S). Therefore, there is an urgent unmet medical need to develop next-generation EGFR TKIs that selectively inhibit EGFR triple mutations via a non-irreversible mechanism. This review covers the fourth-generation EGFR-TKIs' most recent design with their essential binding interactions, the clinical difficulties, and the potential outcomes of treating patients with EGFR mutation C797S resistant to third-generation EGFR-TKIs was also discussed. Moreover, the utilization of various therapeutic strategies, including multi-targeting drugs and combination therapies, has also been reviewed.

Discovery of the allosteric inhibitor from actinomyces metabolites to target EGFRCSTMLR mutant protein: molecular modeling and free energy approach

EGFR (epidermal growth factor receptor), a surface protein on the cell, belongs to the tyrosine kinase family, responsible for cell growth and proliferation. Overexpression or mutation in the EGFR gene leads to various types of cancer, i.e., non-small cell lung cancer, breast, and pancreatic cancer. Bioactive molecules identified in this genre were also an essential source of encouragement for researchers who accomplished the design and synthesis of novel compounds with anticancer properties. World Health Organization (WHO) report states that antibiotic resistance is one of the most severe risks to global well-being, food safety, and development. The world needs to take steps to lessen this danger, such as developing new antibiotics and regulating their use. In this study, 6524 compounds derived from Streptomyces sp. were subjected to drug-likeness filters, molecular docking, and molecular dynamic simulation for 1000 ns to find new triple mutant EGFR^CSTMLR (EGFR-L858R/T790M/C797S) inhibitors. Docking outcomes revealed that five compounds showed better binding affinity (- 9.074 to - 9.3 kcal/mol) than both reference drug CH7233163 (- 6.11 kcal/mol) and co-crystallized ligand Osimertinib (- 8.07 kcal/mol). Further, molecular dynamic simulation confirmed that ligand C_42 exhibited the best interaction at the active site of EGFR protein and comprised a better average radius of gyration (3.87 Å) and average SASA (Solvent Accessible Surface Area) (82.91 Å2) value than co-crystallized ligand (4.49 Å, 222.38 Å2). Additionally, its average RMSD (Root Mean Square Deviation) (3.25 Å) and RMSF (Root Mean Square Fluctuation) (1.54 Å) values were highly similar to co-crystallized ligand (3.07 Å, 1.54 Å). Compared to the reference ligand, it also demonstrated conserved H-bond interactions with the residues MET_793 and GLN_791 with strong interaction probability. In conclusion, we have found a potential drug with no violation of the rule of three, Lipinski's rule of five, and 26 other vital parameters having great potential in medicinal and pharmaceutical industries applications and can overcome synthetic drug issues.

The Resistance to EGFR-TKIs in Non-Small Cell Lung Cancer: From Molecular Mechanisms to Clinical Application of New Therapeutic Strategies

Almost 17% of Western patients affected by non-small cell lung cancer (NSCLC) have an activating epidermal growth factor receptor (EGFR) gene mutation. Del19 and L858R are the most-common ones; they are positive predictive factors for EGFR tyrosine kinase inhibitors (TKIs). Currently, osimertinib, a third-generation TKI, is the standard first-line therapy for advanced NSCLC patients with common EGFR mutations. This drug is also administered as a second-line treatment for those patients with the T790M EGFR mutation and previously treated with first- (erlotinib, gefitinib) or second- (afatinib) generation TKIs. However, despite the high clinical efficacy, the prognosis remains severe due to intrinsic or acquired resistance to EGRF-TKIs. Various mechanisms of resistance have been reported including the activation of other signalling pathways, the development of secondary mutations, the alteration of the downstream pathways, and phenotypic transformation. However, further data are needed to achieve the goal of overcoming resistance to EGFR-TKIs, hence the necessity of discovering novel genetic targets and developing new-generation drugs. This review aimed to deepen the knowledge of intrinsic and acquired molecular mechanisms of resistance to EGFR-TKIs and the development of new therapeutic strategies to overcome TKIs' resistance.

First-Generation Epidermal Growth Factor Receptor Inhibitors Plus Antiangiogenic Drugs Versus Third-Generation Epidermal Growth Factor Receptor Inhibitors in Advanced Non-Small-Cell Lung Cancer: A Meta-Analysis

PURPOSE

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) revolutionized the therapeutic landscape of non-small-cell lung cancer (NSCLC). However, despite significant survival improvement, the emergence of resistance mechanisms represents a common event. In this meta-analysis, we compared the efficacy and safety of third-generation EGFR-TKIs, the current standard of care, to first-generation EGFR-TKIs with antiangiogenic drugs for the first-line treatment of NSCLC harboring EGFR mutations.

MATERIALS AND METHODS

Randomized controlled clinical trials (RCTs) reporting survival data published before September 1, 2022, were searched through the MEDLINE databases (PubMed), the Cochrane Database of Systematic Reviews, and Central Register of Controlled Trials (Wiley). Progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and grade 3 or higher treatment-related adverse events (≥3 TRAEs) data were analyzed.

RESULTS

Twelve RCTs were included in our meta-analysis, with a total of 3,565 patients. We observed that third-generation EGFR-TKIs and first-generation EGFR-TKIs combined with antiangiogenic drugs provided a similar OS benefit over first-generation EGFR-TKIs in any of the subgroups. However, we indirectly observed a greater PFS benefit of third-generation EGFR-TKIs over first-generation EGFR-TKIs in females, never-smokers, in patients harboring exon 19 deletions, and in those with brain metastasis, as compared with using first-generation EGFR-TKIs plus antiangiogenic drugs. The ORR did not differ between the combination strategy and third-generation EGFR-TKIs. Finally, the risk of developing grade ≥3 TRAEs was higher using the combination of first-generation EGFR-TKIs and antiangiogenic drugs over first-generation EGFR-TKIs than third-generation EGFR-TKIs over first-generation EGFR-TKIs.

CONCLUSION

This meta-analysis suggests that the combination strategy may provide an alternative to third-generation EGFR-TKIs, but more data are needed to determine the predictive clinicopathologic characteristics that can influence the treatment choice. Until then, third-generation EGFR-TKIs still represent the first choice in advanced NSCLC harboring EGFR mutations.

Lazertinib in pretreated EGFR T790M-mutated advanced non-small cell lung cancer: A real-world multicenter study

INTRODUCTION

Lazertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that provides a high level of selectivity for sensitizing and p.Thr790Met (T790M) EGFR mutations. We aimed to collect real-world data regarding the efficacy and safety of lazertinib.

METHODS

This study included patients treated with lazertinib for T790M-mutated non-small cell lung cancer who had previously been treated with an EGFR-TKI. The primary outcome measure was progression-free survival (PFS). Additionally, this study evaluated overall survival (OS), time-to-treatment failure (TTF), duration of response (DOR), objective response rate (ORR) and disease control rate (DCR). Drug safety was also assessed.

RESULTS

In a study of 103 patients, 90 received lazertinib as a second- or third-line therapy. The ORR and DCR were 62.1% and 94.2%, respectively. The median follow-up duration was 11.1 months, and the median PFS period was 13.9 (95% confidence interval [CI], 11.0-not reached [NR]) months. OS, DOR, and TTF had not yet been determined. In a subgroup of 33 patients with evaluable brain metastases, the intracranial DCR and ORR were 93.5% and 57.6%, respectively. The median intracranial PFS period was 17.1 (95% CI, 13.9-NR) months. Approximately 17.5% of patients had dose modification or discontinuation due to adverse events, with the most common being grade 1 or 2 paresthesia.

CONCLUSIONS

The efficacy and safety of lazertinib were recapitulated in a real-world study reflecting routine clinical practice in Korea, showing durable disease control both systematically and intracranially, with manageable side effects.

Experimental study of EGFR-TKI aumolertinib combined with ionizing radiation in EGFR mutated NSCLC brain metastases tumor

Aumolertinib is an irreversible third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), although it has been administered for the treatment of epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer (NSCLC). However, it is unclear whether aumolertinib combined with ionizing radiation (IR) has potential therapeutic effects in treating brain metastases (BM) tumors from NSCLC. This study explored the anti-tumor effects of aumolertinib combined with IR in epidermal growth factor receptor mutated (EGFRm) NSCLC BM tumors. First, we established a xenograft model of NSCLC BM tumors in BALB/c nude mice and assessed the anti-tumor effects of this combination. Furthermore, we examined the concentrations of aumolertinib in brain tissue and blood using liquid chromatography-mass spectrometry (LC-MS); after that, we used CCK-8, colony formation, flow cytometry assay, and immunofluorescence staining to detect the effects of aumolertinib combined with IR upon PC-9 and NCI-H1975 cells, such as cell proliferation, survival, apoptosis, cycle distribution, the situation of DNA damage, and the expression levels of relevant proteins which were detected via western blotting; finally, we chose a clinical case with which to explore the clinical benefits to the EGFRm NSCLC BM patient after the treatment of the aforementioned combination. The experiments of NSCLC BM tumor animal models demonstrated that the combination enhanced the therapeutic effects and increased the intracranial accumulation of aumolertinib; the combination can inhibit cell proliferation and survival, delay the repair of DNA damage, and increase the rates of cell apoptosis and aumolertinib abrogated G2/M phase arrest, which the IR induced; the clinical study verified that the combination demonstrated better patient benefits. In conclusion, our study demonstrated that combining aumolertinib and IR has promising anti-tumor effects in EGFR-mutant NSCLC and that this combined treatment modality may be employed as a potential therapeutic strategy for EGFR-mutant NSCLC BM patients clinically.

Using human genetics to improve safety assessment of therapeutics

Human genetics research has discovered thousands of proteins associated with complex and rare diseases. Genome-wide association studies (GWAS) and studies of Mendelian disease have resulted in an increased understanding of the role of gene function and regulation in human conditions. Although the application of human genetics has been explored primarily as a method to identify potential drug targets and support their relevance to disease in humans, there is increasing interest in using genetic data to identify potential safety liabilities of modulating a given target. Human genetic variants can be used as a model to anticipate the effect of lifelong modulation of therapeutic targets and identify the potential risk for on-target adverse events. This approach is particularly useful for non-clinical safety evaluation of novel therapeutics that lack pharmacologically relevant animal models and can contribute to the intrinsic safety profile of a drug target. This Review illustrates applications of human genetics to safety studies during drug discovery and development, including assessing the potential for on- and off-target associated adverse events, carcinogenicity risk assessment, and guiding translational safety study designs and monitoring strategies. A summary of available human genetic resources and recommended best practices is provided. The challenges and future perspectives of translating human genetic information to identify risks for potential drug effects in preclinical and clinical development are discussed.

Small Molecule EGFR Inhibitors as Anti-Cancer Agents: Discovery, Mechanisms of Action, and Opportunities

Epidermal growth factor receptors (EGFRs) are a class of receptor tyrosine kinase that are also called ErbB1 and HER1. EGFR tyrosine kinase activity inhibition is considered a promising therapeutic strategy for the treatment of cancer. Many small-molecule inhibitors of EGFR tyrosine kinase (EGFR-TK), from medicinally privileged molecules to commercial drugs, have been overviewed. Particular attention has been paid to the structure of the molecule and its mechanism of action if reported. Subsequent classification of the molecules under discussion has been carried out. Both natural and synthetic and reversible and irreversible EGFR-tyrosine kinase inhibitors have been discussed. Various types of cancers that are caused by overexpression of the EGFR gene, their possible molecular origins, and their natures have also been counted in this article. Because the EGFR signaling pathway controls the proliferation, growth, survival, and differentiation of cells, and the mutated EGFR gene overproduces EGFR protein, which ultimately causes several types of cancer, proper understanding of the molecular dynamics between the protein structure and its inhibitors will lead to more effective and selective EGFR-TKIs, which in turn will be able to save more lives in the battle against cancer.

Structure-Guided Strategies of Targeted Therapies for Patients with EGFR-Mutant Non-Small Cell Lung Cancer

Oncogenic mutations within the EGFR kinase domain are well-established driver mutations in non-small cell lung cancer (NSCLC). Small-molecule tyrosine kinase inhibitors (TKIs) specifically targeting these mutations have improved treatment outcomes for patients with this subtype of NSCLC. The selectivity of these targeted agents is based on the location of the mutations within the exons of the EGFR gene, and grouping mutations based on structural similarities has proved a useful tool for conceptualizing the heterogeneity of TKI response. Structure-based analysis of EGFR mutations has influenced TKI development, and improved structural understanding will inform continued therapeutic development and further improve patient outcomes. In this review, we summarize recent progress on targeted therapy strategies for patients with EGFR-mutant NSCLC based on structure and function analysis.

Approved Small-Molecule ATP-Competitive Kinases Drugs Containing Indole/Azaindole/Oxindole Scaffolds: R&D and Binding Patterns Profiling

Kinases are among the most important families of biomolecules and play an essential role in the regulation of cell proliferation, apoptosis, metabolism, and other critical physiological processes. The dysregulation and gene mutation of kinases are linked to the occurrence and development of various human diseases, especially cancer. As a result, a growing number of small-molecule drugs based on kinase targets are being successfully developed and approved for the treatment of many diseases. The indole/azaindole/oxindole moieties are important key pharmacophores of many bioactive compounds and are generally used as excellent scaffolds for drug discovery in medicinal chemistry. To date, 30 ATP-competitive kinase inhibitors bearing the indole/azaindole/oxindole scaffold have been approved for the treatment of diseases. Herein, we summarize their research and development (R&D) process and describe their binding models to the ATP-binding sites of the target kinases. Moreover, we discuss the significant role of the indole/azaindole/oxindole skeletons in the interaction of their parent drug and target kinases, providing new medicinal chemistry inspiration and ideas for the subsequent development and optimization of kinase inhibitors.

Results of the phase IIa study to evaluate the efficacy and safety of rezivertinib (BPI-7711) for the first-line treatment of locally advanced or metastatic/recurrent NSCLC patients with EGFR mutation from a phase I/IIa study

BACKGROUND

Rezivertinib (BPI-7711) is a novel third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI). This phase IIa study was part of a phase I/IIa study (NCT03386955), aimed to evaluate the efficacy and safety of rezivertinib as the first-line treatment for patients with locally advanced or metastatic/recurrent EGFR mutated non-small cell lung cancer (NSCLC).

METHODS

Patients received the first-line treatment of 180 mg rezivertinib orally once daily until disease progression, unacceptable toxicity, or withdrawal of consent. The primary endpoint was the objective response rate (ORR) assessed by blinded independent central review (BICR). Secondary endpoints included disease control rate (DCR), duration of response (DoR), progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

From Jun 12, 2019, to Oct 17, 2019, 43 patients were enrolled. At the data cutoff date on Dec 23, 2021, the ORR by BICR was 83.7% (95% CI: 69.3-93.2%). The median DoR was 19.3 (95% CI: 15.8-25.0) months. The median PFS by BICR was 20.7 (95% CI: 13.8-24.8) months and 22.0 (95% CI: 16.8-26.3) months by investigators. Data on OS was immature. Totally, 40 (93.0%) patients had at least one treatment-related adverse event while 4 (9.3%) of them were grade ≥ 3.

CONCLUSIONS

Rezivertinib (BPI-7711) showed promising efficacy and a favorable safety profile for the treatment among the locally advanced or metastatic/recurrent NSCLC patients with EGFR mutation in the first-line setting.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03386955.

Simultaneous quantitation of befotertinib (D-0316) and its metabolite D-0865 in human plasma by LC-MS/MS method

A sensitive and reliable method was developed to determine befotertinib (D-0316) and its metabolite D-0865 from human plasma by LC-MS/MS. The samples were prepared by simple protein precipitation and 2 µL of the supernatant were chromatographed on a C18 analytical column (ACE Excel 2 Super C₁₈, 50 × 2.1 mm). Elution was performed with mobile phase A (10 mM ammonium acetate in water containing 1 % formic acid) and mobile phase B (acetonitrile containing 1 % formic acid) under a gradient program in a total run time of 4 min. Triple Quadruple 5500 equipped with Turbo Ion Spray source and multiple reaction monitoring (MRM) were used for the analysis detection. The transitions were m/z 568.3 → 72.1 m/z (befotertinib), m/z 554.2 → 497.2 (D-0865), and m/z 455.2 → 164.9 (verapamil, internal standard). According to the Chinese Pharmacopeia Commission and ICH Harmonised Guideline for Bioanalytical Method Validation, this method was validated within the spectrum of its accuracy, precision, selectivity, linearity, recovery, matrix effect, and stability. This LC-MS/MS method was successfully applied for the quantitation of befotertinib and its metabolite D-0865 in human plasma during the pharmacokinetics study of befotertinib in non-small cell lung cancer (NSCLC) patients.

Monitoring EGFR-lung cancer evolution: a possible beginning of a "methylation era" in TKI resistance prediction

The advances in scientific knowledge on biological therapies of the last two decades have impressively oriented the clinical management of non-small-cell lung cancer (NSCLC) patients. The treatment with tyrosine kinase inhibitors (TKIs) in patients harboring Epidermal Growth Factor Receptor (EGFR)-activating mutations is dramatically associated with an improvement in disease control. Anyhow, the prognosis for this selected group of patients remains unfavorable, due to the innate and/or acquired resistance to biological therapies. The methylome analysis of many tumors revealed multiple patterns of methylation at single/multiple cytosine-phosphate-guanine (CpG) sites that are linked to the modulation of several cellular pathways involved in cancer onset and progression. In lung cancer patients, ever increasing evidences also suggest that the association between DNA methylation changes at promoter/intergenic regions and the consequent alteration of gene-expression signatures could be related to the acquisition of resistance to biological therapies. Despite this intriguing hypothesis, large confirmatory studies are demanded to consolidate and finalize many preliminary observations made in this field. In this review, we will summarize the available knowledge about the dynamic role of DNA methylation in EGFR-mutated NSCLC patients.

Leveraging Molecular and Immune-Based Therapies in Leptomeningeal Metastases

Leptomeningeal metastases represent an aggressive stage of cancer with few durable treatment options. Improved understanding of cancer biology, neoplastic reliance on oncogenic driver mutations, and complex immune system interactions have resulted in an explosion in cancer-directed therapy in the last two decades to include small molecule inhibitors and immune checkpoint inhibitors. Most of these therapeutics are underexplored in patients with leptomeningeal metastases, limiting extrapolation of extracranial and even intracranial efficacy outcomes to the unique leptomeningeal space. Further confounding our interpretation of drug activity in the leptomeninges is an incomplete understanding of drug penetration through the blood-cerebrospinal fluid barrier of the choroid plexus. Nevertheless, a number of retrospective studies and promising prospective trials provide evidence of leptomeningeal activity of several small molecule and immune checkpoint inhibitors and underscore potential areas of further therapeutic development for patients harboring leptomeningeal disease.

Effects of voriconazole and fluconazole on the pharmacokinetics of almonertinib in rats by UPLC-MS/MS

Almonertinib was included in the first-line treatment of non-small cell lung cancer with EGFR T790M mutations by the Chinese Society of Clinical Oncology in 2021. Considering that immunocompromised lung cancer patients are prone to opportunistic fungal infections, and most triazole antifungal drugs are moderate or strong inhibitors of CYP3A4, this study was conducted to develop and validate an accurate and rapid ultra-performance liquid chromatography tandem mass spectrometry method for quantifying almonertinib in plasma and for investigating the pharmacokinetic changes of almonertinib caused by voriconazole and fluconazole in rats. After liquid-liquid extraction with tert-butyl methyl ether, an XSelect HSS T3 column (2.1 × 100 mm, 2.5 μm, Waters) was used for the chromatographic separation of almonertinib and sorafenib-D₃ (internal standard). The analytes were detected using an AB Sciex Triple Quad 5,500 mass spectrometer in the positive ionization mode. The method exhibited great linearity (0.5-200 ng/ml, r > 0.997) and stability under the established experimental conditions. All validation experiments were in accordance with the guidelines, and the results were all within the acceptable limits. This method was successfully applied to the researches of pharmacokinetics and drug interactions for almonertinib in rats. Voriconazole and fluconazole significantly altered the pharmacokinetic profiles of almonertinib and increased the systemic exposure of almonertinib in rats to different degrees, but further human trials should be conducted to validate the results.

Molecular pathways, resistance mechanisms and targeted interventions in non-small-cell lung cancer

Lung cancer is the leading cause of cancer-related mortality worldwide. The discovery of tyrosine kinase inhibitors effectively targeting EGFR mutations in lung cancer patients in 2004 represented the beginning of the precision medicine era for this refractory disease. This great progress benefits from the identification of driver gene mutations, and after that, conventional and new technologies such as NGS further illustrated part of the complex molecular pathways of NSCLC. More targetable driver gene mutation identification in NSCLC patients greatly promoted the development of targeted therapy and provided great help for patient outcomes including significantly improved survival time and quality of life. Herein, we review the literature and ongoing clinical trials of NSCLC targeted therapy to address the molecular pathways and targeted intervention progress in NSCLC. In addition, the mutations in EGFR gene, ALK rearrangements, and KRAS mutations in the main sections, and the less common molecular alterations in MET, HER2, BRAF, ROS1, RET, and NTRK are discussed. The main resistance mechanisms of each targeted oncogene are highlighted to demonstrate the current dilemma of targeted therapy in NSCLC. Moreover, we discuss potential therapies to overcome the challenges of drug resistance. In this review, we manage to display the current landscape of targetable therapeutic patterns in NSCLC in this era of precision medicine.

EGFR-Mutant Non-small Cell Lung Cancer: State-of-the-Art and Future Perspectives

EGFR mutations are the first identified targetable driver alterations in advanced non-small cell lung cancer (NSCLC), for which specific epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKI) have been developed. These small molecules, administered orally, changed the natural history of patients with EGFR-mutated NSCLC, reporting impressive response and survival data. Osimertinib, a third-generation EGFR-TKI, can be considered the standard first-line therapy for the ‘common’ EGFR mutations, which include the exon 19 deletion and Leu858Arg point mutation in exon 21, accounting for 90% of cases. The ‘uncommon’ EGFR mutations, highly heterogeneous and with a low frequency, seem to be more sensitive to afatinib and osimertinib, a second-generation EGFR-TKI, excluding the EGFR exon 20 insertions mutations, for which a platinum-based regimen should be recommended while waiting for specific targeted inhibitors to reach the market. However, after an initial activity to first-line EGFR-TKI treatment, a disease progression is reported due to the presence of an intrinsic resistance or the onset of an acquired resistance. The latter can be broadly grouped into EGFR-dependent or EGFR-independent mechanisms of resistance, for which several new drugs and strategic approaches are under investigation. This review focuses on the state-of-the-art EGFR-TKIs in the treatment of metastatic NSCLC harbouring EGFR mutations, and also discusses potential future perspectives.