rociletinib and Lung-Neoplasms

EGFR T790M mutation leads to resistance to most of clinically available EGFR TKIs. Third-generation EGFR TKIs against the T790M mutation have been in active clinical development, which includes osimertinib, rociletinib, HM61713, ASP8273, EGF816, and PF-06747775. On the other hand recently EGFR C797S mutation was reported to be a leading mechanism of resistance to the third-generation inhibitors. The C797S mutation appears to be an ideal target for overcoming the acquired resistance to the third generation inhibitors. This review summarizes the third generation inhibitors, synthesis, their mechanism of resistance and latest development on the discovery of a fourth-generation EGFR TKIs and U to Y allosteric strategies to combat the C797S EGFR resistance problem.

Topics: Animals; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Drug Discovery; Drug Resistance, Neoplasm; ErbB Receptors; Humans; Lung; Lung Neoplasms; Models, Molecular; Point Mutation; Protein Kinase Inhibitors

In 2015, the FDA approved an unprecedented number of new therapies for non-small cell lung cancer (NSCLC), among them therapies addressing specific genomic tumor subsets in the setting of development of resistance to first-line targeted therapy. Osimertinib (Tagrisso, formerly AZD9291; AstraZeneca) is indicated for patients with metastatic EGFR T790M mutation-positive NSCLC, as detected by an FDA-approved test, who have progressed on or after EGFR tyrosine kinase inhibitor therapy. It received breakthrough therapy designation, priority review status, and accelerated approval from the FDA. Clin Cancer Res; 23(3); 618-22. ©2016 AACR.

Topics: Acrylamides; Adenosine Triphosphate; Aniline Compounds; Antineoplastic Agents; Binding Sites; Carcinoma, Non-Small-Cell Lung; Clinical Trials, Phase I as Topic; Clinical Trials, Phase II as Topic; Diarrhea; Disease Progression; Drug Eruptions; Drug Resistance, Neoplasm; ErbB Receptors; Genes, erbB-1; Humans; Lung Diseases, Interstitial; Lung Neoplasms; Molecular Targeted Therapy; Mutation, Missense; Neoplasm Proteins; Piperazines; Point Mutation; Protein Kinase Inhibitors; Pyrimidines; Salvage Therapy; Single-Blind Method

Patients with epidermal growth factor receptor (EGFR) mutation-positive nonsmall cell lung cancer (NSCLC) develop resistance during therapy with EGFR tyrosine kinase inhibitors (TKIs). In about half of the patients, this resistance is because of the emergence of the T790M mutation. Third-generation TKIs are active against EGFR-activating mutations and the T790M resistance mutation and have only limited efficacy against wild-type EGFR. Here we review the current status of the clinical development of these novel TKIs.. Third-generation TKIs in clinical development include osimertinib, rociletinib, and HM61713. Osimertinib and rociletinib have shown clinical efficacy in phase I/II trials in patients who had acquired resistance to first- or second-generation TKIs. Both TKIs are currently further evaluated in phase III trials as first-line or second-line therapy in patients with advanced EGFR mutation-positive NSCLC. HM61713 is in early clinical development.. Third-generation EGFR TKIs have shown activity in patients with acquired resistance to first- and second-generation EGFR TKIs and may further improve clinical outcome in patients with advanced EGFR mutation-positive NSCLC.

Topics: Acrylamides; Aniline Compounds; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Non-Small-Cell Lung; Drug Resistance, Neoplasm; ErbB Receptors; Humans; Lung Neoplasms; Mutation; Piperazines; Protein Kinase Inhibitors; Pyrimidines

Major advances have been made since the discovery of driver mutations and their targeted therapies, especially in the treatment of patients with epidermal growth factor receptor (EGFR) mutations. Despite their initial efficacy in the majority of the patients with such driver mutations, all targeted therapies are limited by the eventual development of resistance mechanisms.. EGFR T790M mutation is a common resistance mechanism after treatment with first or second generation EGFR tyrosine kinase inhibitors (TKI). Rociletinib is one of the third generation EGFR TKIs with activity against T790M and activating EGFR mutations while sparing the wild-type EGFR. In this review, we discuss the current understanding and available data on rociletinib, including the side effects associated with the medication. We will also review the BEAMing plasma test to detect T790M mutation without the need for repeat biopsy. Lastly, we review the potential resistance mechanisms after progression on rociletinib, and future directions.. It is important to note that there are other 3(rd) generation EGFR TKIs with activity against T790M already approved by the US FDA (osimertinib) and many others in development. Future research will focus on figuring out which patients can benefit the most from a particular medication with minimal side effects, and further resistance mechanisms after rociletinib.

Topics: Acrylamides; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Clinical Trials as Topic; Drug Resistance, Neoplasm; ErbB Receptors; Humans; Lung Neoplasms; Mutation; Protein Kinase Inhibitors; Pyrimidines

The tyrosine kinase inhibitors (TKI) against epidermal growth factor receptor (EGFR) are widely used in patients with non-small cell lung cancer (NSCLC). However, EGFR T790M mutation leads to resistance to most clinically available EGFR TKIs. Third-generation EGFR TKIs against the T790M mutation have been in active clinical development. These agents include osimertinib, rociletinib, HM61713, ASP8273, EGF816, and PF-06747775. Osimertinib and rociletinib have shown clinical efficacy in phase I/II trials in patients who had acquired resistance to first- or second-generation TKIs. Osimertinib (AZD9291, TAGRISSO) was recently approved by FDA for metastatic EGFR T790M mutation-positive NSCLC. HM61713, ASP8237, EGF816, and PF-06747775 are still in early clinical development. This article reviews the emerging data regarding third-generation agents against EGFR T790M mutation in the treatment of patients with advanced NSCLC.

Topics: Acrylamides; Aniline Compounds; Carcinoma, Non-Small-Cell Lung; Clinical Trials as Topic; Drug Resistance, Neoplasm; ErbB Receptors; Humans; Lung Neoplasms; Mutation, Missense; Piperazines; Protein Kinase Inhibitors; Pyrimidines

Activating EGFR mutations discovery and efficacy of 1st generation tyrosine kinase inhibitors (TKI), such as erlotinib or gefitinib, inaugurated the beginning of personalized medicine in the treatment of EGFR-mutated non-small cell lung cancer (NSCLC). However, all patients showed a tumor progression of 10 to 16 months after the onset of TKI therapy related to molecular resistance mechanisms as T790M mutation. Till now, patients suffering from EGFR-mutated NSCLC with acquired resistance have conventional treatment options. Two new 3rd generations' TKI, AZD9291 and rociletinib, are currently being studied in phases 1-3 studies. Preliminary results show relevant therapeutic properties in patients with T790M mutated-EGFR NSCLC. This review aims to highlight these new molecules, their effectiveness and their clinical toxicities in the treatment of advanced stages of NSCLC expressing the T790M mutation.

Topics: Acrylamides; Aniline Compounds; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Disease Progression; Drug Resistance, Neoplasm; ErbB Receptors; Humans; Lung Neoplasms; Mutation; Protein Kinase Inhibitors; Pyrimidines

A major limitation of circulating tumor DNA (ctDNA) for somatic mutation detection has been the low level of ctDNA found in a subset of cancer patients. We investigated whether using a combined isolation of exosomal RNA (exoRNA) and cell-free DNA (cfDNA) could improve blood-based liquid biopsy for EGFR mutation detection in non-small-cell lung cancer (NSCLC) patients.. Matched pretreatment tumor and plasma were collected from 84 patients enrolled in TIGER-X (NCT01526928), a phase 1/2 study of rociletinib in mutant EGFR NSCLC patients. The combined isolated exoRNA and cfDNA (exoNA) was analyzed blinded for mutations using a targeted next-generation sequencing panel (EXO1000) and compared with existing data from the same samples using analysis of ctDNA by BEAMing.. For exoNA, the sensitivity was 98% for detection of activating EGFR mutations and 90% for EGFR T790M. The corresponding sensitivities for ctDNA by BEAMing were 82% for activating mutations and 84% for T790M. In a subgroup of patients with intrathoracic metastatic disease (M0/M1a; n = 21), the sensitivity increased from 26% to 74% for activating mutations (P = 0.003) and from 19% to 31% for T790M (P = 0.5) when using exoNA for detection.. Combining exoRNA and ctDNA increased the sensitivity for EGFR mutation detection in plasma, with the largest improvement seen in the subgroup of M0/M1a disease patients known to have low levels of ctDNA and poses challenges for mutation detection on ctDNA alone.. NCT01526928.

Topics: Acrylamides; Adult; Aged; Antineoplastic Agents; Biomarkers, Tumor; Carcinoma, Non-Small-Cell Lung; Circulating Tumor DNA; DNA Mutational Analysis; ErbB Receptors; Exosomes; Female; Genes, erbB-1; Humans; Liquid Biopsy; Lung Neoplasms; Male; Middle Aged; Pyrimidines; RNA; Sensitivity and Specificity

The genomic alterations driving resistance to third-generation EGFR tyrosine kinase inhibitors (TKIs) are not well established, and collecting tissue biopsy samples poses potential complications from invasive procedures. Cell-free circulating DNA (cfDNA) testing provides a noninvasive approach to identify potentially targetable mechanisms of resistance. Here we utilized a 70-gene cfDNA next-generation sequencing test to interrogate pretreatment and progression samples from 77 EGFR-mutated non-small cell lung cancer (NSCLC) patients treated with a third-generation EGFR TKI.. Rociletinib was evaluated in advanced or metastatic (second line or higher) disease with EGFR T790M-positive NSCLC in the TIGER-X (NCT01526928) and TIGER-2 (NCT02147990) studies. Plasma samples were collected at baseline and at the time of systemic progression while receiving rociletinib. The critical exons in 70 genes were sequenced in cfDNA isolated from plasma samples to elucidate a comprehensive genomic profile of alterations for each patient.. Plasma-based cfDNA analysis identified 93% of the initial EGFR activating and 85% of the EGFR T790M resistance mutations in pretreatment samples with detectable tumor DNA. Profiling of progression samples revealed significant heterogeneity, with different variant types (eg, mutations, amplifications, and fusions) detected in multiple genes (EGFR, MET, RB1) that may be driving resistance in patients. Novel alterations not previously described in association with resistance to third-generation TKIs were also detected, such as an NTRK1 fusion.. cfDNA next-generation sequencing identified initial EGFR activating and secondary T790M resistance mutations in NSCLC patients with high sensitivity, predicted treatment response equivalent to tissue analysis, and identified multiple novel and established resistance alterations.

Topics: Acrylamides; Adult; Aged; Aged, 80 and over; Antinematodal Agents; Carcinoma, Non-Small-Cell Lung; Cell-Free Nucleic Acids; Drug Resistance, Neoplasm; ErbB Receptors; Female; High-Throughput Nucleotide Sequencing; Humans; Lung Neoplasms; Male; Middle Aged; Mutation; Neoplasm Metastasis; Neoplasm Staging; Prognosis; Pyrimidines; Treatment Outcome

Topics: Acrylamides; Aniline Compounds; Antineoplastic Agents; Disease Progression; Disease-Free Survival; Female; Humans; Lung Neoplasms; Male; Piperazines; Pyrimidines

The evaluation of plasma testing for the EGFR resistance mutation T790M in NSCLC patients has not been broadly explored. We investigated the detection of EGFR activating and T790M mutations in matched tumor tissue and plasma, mostly from patients with acquired resistance to first-generation EGFR inhibitors.. Samples were obtained from two studies, an observational study and a phase I trial of rociletinib, a mutant-selective inhibitor of EGFR that targets both activating mutations and T790M. Plasma testing was performed with the cobas EGFR plasma test and BEAMing.. The positive percent agreement (PPA) between cobas plasma and tumor results was 73% (55/75) for activating mutations and 64% (21/33) for T790M. The PPA between BEAMing plasma and tumor results was 82% (49/60) for activating mutations and 73% (33/45) for T790M. Presence of extrathoracic (M1b) versus intrathoracic (M1a/M0) disease was found to be strongly associated with ability to identify EGFR mutations in plasma (P < 0.001). Rociletinib objective response rates (ORR) were 52% [95% confidence interval (CI), 31 - 74%] for cobas tumor T790M-positive and 44% (95% CI, 25 - 63%) for BEAMing plasma T790M-positive patients. A drop in plasma-mutant EGFR levels to ≤10 molecules/mL was seen by day 21 of treatment in 7 of 8 patients with documented partial response.. These findings suggest the cobas and BEAMing plasma tests can be useful tools for noninvasive assessment and monitoring of the T790M resistance mutation in NSCLC, and could complement tumor testing by identifying T790M mutations missed because of tumor heterogeneity or biopsy inadequacy. Clin Cancer Res; 22(10); 2386-95. ©2016 AACR.

Topics: Acrylamides; Adult; Aged; Aged, 80 and over; Carcinoma, Non-Small-Cell Lung; Drug Resistance, Neoplasm; ErbB Receptors; Female; Humans; Lung Neoplasms; Male; Middle Aged; Mutation; Protein Kinase Inhibitors; Pyrimidines

Non-small-cell lung cancer (NSCLC) with a mutation in the gene encoding epidermal growth factor receptor (EGFR) is sensitive to approved EGFR inhibitors, but resistance develops, mediated by the T790M EGFR mutation in most cases. Rociletinib (CO-1686) is an EGFR inhibitor active in preclinical models of EGFR-mutated NSCLC with or without T790M.. In this phase 1-2 study, we administered rociletinib to patients with EGFR-mutated NSCLC who had disease progression during previous treatment with an existing EGFR inhibitor. In the expansion (phase 2) part of the study, patients with T790M-positive disease received rociletinib at a dose of 500 mg twice daily, 625 mg twice daily, or 750 mg twice daily. Key objectives were assessment of safety, side-effect profile, pharmacokinetics, and preliminary antitumor activity of rociletinib. Tumor biopsies to identify T790M were performed during screening. Treatment was administered in continuous 21-day cycles.. A total of 130 patients were enrolled. The first 57 patients to be enrolled received the free-base form of rociletinib (150 mg once daily to 900 mg twice daily). The remaining patients received the hydrogen bromide salt (HBr) form (500 mg twice daily to 1000 mg twice daily). A maximum tolerated dose (the highest dose associated with a rate of dose-limiting toxic effects of less than 33%) was not identified. The only common dose-limiting adverse event was hyperglycemia. In an efficacy analysis that included patients who received free-base rociletinib at a dose of 900 mg twice daily or the HBr form at any dose, the objective response rate among the 46 patients with T790M-positive disease who could be evaluated was 59% (95% confidence interval [CI], 45 to 73), and the rate among the 17 patients with T790M-negative disease who could be evaluated was 29% (95% CI, 8 to 51).. Rociletinib was active in patients with EGFR-mutated NSCLC associated with the T790M resistance mutation. (Funded by Clovis Oncology; ClinicalTrials.gov number, NCT01526928.).

Topics: Acrylamides; Aged; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Dose-Response Relationship, Drug; Drug Resistance, Neoplasm; ErbB Receptors; Female; Humans; Hyperglycemia; Lung Neoplasms; Male; Middle Aged; Mutation; Protein Kinase Inhibitors; Pyrimidines

Tyrosine kinase inhibitors (TKIs) are used for the treatment of both wild type and mutant non-small cell lung cancer (NSCLC); however, acquired resistance is a major clinical challenge. Herein, we aimed to investigate the effects of telmisartan (Tel), CFM 4.16 and sorafenib combination in rociletinib resistant NSCLC tumors.. 3D spheroid cultures and western blotting were used for evaluating cytotoxic effects and protein expression. An in vivo rociletinib resistant H1975 xenograft model of NSCLC was developed by subcutaneous injection of rociletinib resistant H1975 cells into nude mice.. Tel, CFM 4.16 and sorafenib combination displayed superior anti-cancer effects in 3D spheroid cultures and a rociletinib resistant H1975 xenograft model of NSCLC by decreasing the protein expression of oncogenic and cancer stem cell markers (Nanog, Sox2 and Oct4).. Tel facilitates effective penetration of CFM 4.16 and sorafenib in rociletinib resistant H1975 models of NSCLC.

Topics: Acrylamides; Animals; Biomarkers, Tumor; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Proliferation; Cell Survival; Down-Regulation; Drug Resistance, Neoplasm; Drug Synergism; Gene Expression Regulation, Neoplastic; Humans; Lung Neoplasms; Mice; Mice, Nude; Pyrimidines; Sorafenib; Spheroids, Cellular; Spiro Compounds; Telmisartan; Thiadiazoles; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Targeting the epidermal growth factor receptor (EGFR) with tyrosine kinase inhibitors (TKIs) is one of the major precision medicine treatment options for lung adenocarcinoma. Due to common development of drug resistance to first- and second-generation TKIs, third-generation inhibitors, including osimertinib and rociletinib, have been developed. A model of EGFR-driven lung cancer and a method to develop tumors of distinct epigenetic states through 3D organotypic cultures are described here. It is discovered that activation of the EGFR T790M/L858R mutation in lung epithelial cells can drive lung cancers with alveolar or bronchiolar features, which can originate from alveolar type 2 (AT2) cells or bronchioalveolar stem cells, but not basal cells or club cells of the trachea. It is also demonstrated that these clones are able to retain their epigenetic differences through passaging orthotopically in mice and crucially that they have distinct drug vulnerabilities. This work serves as a blueprint for exploring how epigenetics can be used to stratify patients for precision medicine decisions.

Topics: Acrylamides; Aniline Compounds; Animals; Antineoplastic Agents; Cell Line, Tumor; Disease Models, Animal; ErbB Receptors; Female; Humans; Lung Neoplasms; Male; Mice; Mice, Nude; Precision Medicine; Protein Kinase Inhibitors; Pyrimidines; Treatment Outcome

Rociletinib showed activity in T790M-positive non-small cell lung cancer patients. It undergoes amide hydrolysis to form M502, followed by N-acetylation to M544 or amide hydrolysis to M460. We identified the enzymes responsible for rociletinib metabolism, and investigated the relationship between M544 formation and N-acetyltransferase 2 (NAT2) polymorphisms.. Rociletinib and metabolites were incubated with carboxylesterase (CES)1b, CES1c, CES2, NAT1, NAT2, arylacetamide deacetylase, inhibitors, pooled human liver microsomes (HLM) and cytosols (HLC). Cytosols (n = 107) were genotyped for NAT2 polymorphisms (rs1041983 and rs1801280) and incubated with M502. Human hepatocytes from intermediate (NAT2*6/*12A) and slow (NAT2*5B/*5B) acetylators were incubated with 10 μM rociletinib and metabolites for 24 hours. Metabolites were measured by high-performance liquid chromatography.. M502 was formed from rociletinib and M544 by CES2 and HLM; M544 and N-acetyl-M460 were formed by NAT2 and HLC; M460 was not formed by CES or arylacetamide deacetylase. M502 formation by HLM was inhibited by bis-(4-nitrophenyl)phosphate and eserine (10 μM). M544 formation in HLC was inhibited by 100 μM quercetin and was associated with NAT2 genotype (P < .0001). M460 formation in HLM was inhibited by eserine, and M460 was N-acetylated in HLC. Hepatocytes formed M502, M544 and M460. The intermediate acetylator showed higher production (range: 3.4-5.1-fold) of N-acetylated metabolites than the slow acetylator.. Results indicate that NAT2 and CES2 are involved in rociletinib metabolism, and polymorphic NAT2 could alter drug exposure in patients. Slow NAT2 acetylators would have higher exposure to M502 and M460 and consequently, be at increased risk of experiencing hyperglycaemia and QTc prolongation.

Topics: Acetylation; Acetyltransferases; Acrylamides; Arylamine N-Acetyltransferase; Carcinoma, Non-Small-Cell Lung; ErbB Receptors; Genotype; Humans; Lung Neoplasms; Mutation; Polymorphism, Genetic; Protein Kinase Inhibitors; Pyrimidines

Topics: Acrylamides; Aged; Aniline Compounds; Carcinoma, Non-Small-Cell Lung; Disease Progression; ErbB Receptors; Humans; Lung Neoplasms; Male; Neoplasm Metastasis; Piperazines; Pyrimidines

A new class of thiodiphenylpyrimidine analogs (Thio-DPPY) were synthesized as potent and selective EGFR T790M inhibitors to overcome gefitinib resistance in nonsmall cell lung cancer (NSCLC). This structural optimization led to the identification of two potent EGFR

Topics: Acrylamides; Antineoplastic Agents; Binding Sites; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Proliferation; Drug Resistance, Neoplasm; Drug Screening Assays, Antitumor; ErbB Receptors; Humans; Lung Neoplasms; Molecular Docking Simulation; Mutagenesis, Site-Directed; Protein Kinase Inhibitors; Protein Structure, Tertiary; Pyrimidines; Structure-Activity Relationship

Third-generation irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), rociletinib (CO-1686), is great efficacy against EGFR-mutated patients bearing the T790M resistance mutation. However, acquired resistance may emerge. There is a need to characterize acquired resistance mechanism(s) and to devise ways to overcome CO-1686 resistance.. MTT assay, ki67 incorporation assay, transwell assay and TUNEL assay were employed to analyze the effects of metformin to reverse CO-1686 resistance in vitro. The NF-κB activity was measured by the antibody of p50, p65, p-IKBɑ, and p-IKKɑ/β. Western blotting was used to analyze the proteins in cells.. We have established CO-1686-resistant cell lines of PC-9GRCOR and H1975COR from two parental cell lines of PC-9GR and H1975 by long-term exposure to increasing doses of CO-1686. Compared with the parental cells, PC-9GRCOR cells and H1975COR cells showed 90-folds and 20-folds higher resistance to CO-1686, respectively. Critically, we showed that the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling molecular proteins subunits of p50, p65 and its inhibitor proteins of IKBɑ, IKKɑ/β in phosphorylation levels in resistant cells were higher than parental cells. Accordingly, inhibition of NF-κB activity used TPCA-1 effective in decreasing viability and inducing apoptosis of resistant cells. Moreover, metformin overcame the acquired resistance to CO-1686 by reducing cell proliferation and invasion. Metformin combined with CO-1686 synergistically inhibited the p-IKBɑ, p-IKKɑ/β, p50, and p65.. NF-κB signaling activation induced acquired resistance to CO-1686. Metformin sensitized resistant cells to CO-1686 via inhibiting NF-κB signaling.

Topics: Acrylamides; Apoptosis; Cell Line, Tumor; Cell Proliferation; China; Drug Resistance; Drug Synergism; ErbB Receptors; Humans; Hypoglycemic Agents; Lung Neoplasms; Metformin; NF-kappa B; Phosphorylation; Protein Kinase Inhibitors; Pyrimidines; Signal Transduction

The specific targeting of oncogenic mutant epidermal growth factor receptor (EGFR) is a breakthrough in targeted cancer therapy and marks a drastic change in the treatment of non-small cell lung cancer (NSCLC). The recurrent emergence of resistance to these targeted drugs requires the development of novel chemical entities that efficiently inhibit drug-resistant EGFR. Herein, we report the optimization process for a hit compound that has emerged from a phenotypic screen resulting in indazole-based compounds. These inhibitors are conformationally less flexible, target gatekeeper mutated drug-resistant EGFR-L858R/T790M, and covalently alkylate Cys797. Western blot analysis, as well as characterization of the binding kinetics and kinase selectivity profiling, substantiates our approach of targeting drug-resistant EGFR-L858R/T790M with inhibitors incorporating the indazole as hinge binder.

Topics: Animals; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Drug Resistance, Neoplasm; ErbB Receptors; Humans; Indazoles; Lung; Lung Neoplasms; Mice; Molecular Docking Simulation; Mutation; Protein Kinase Inhibitors

On the basis of Ibrutinib's core pharmacophore, which was moderately active to EGFR T790M mutant, we discovered novel epidermal growth factor receptor (EGFR) inhibitor compound 19 (CHMFL-EGFR-202), which potently inhibited EGFR primary mutants (L858R, del19) and drug-resistant mutant L858R/T790M. Compound 19 displayed a good selectivity profile among 468 kinases/mutants tested in the KINOMEscan assay (S score (1) = 0.02). In particular, it did not exhibit apparent activities against INSR and IGF1R kinases. The X-ray crystal structure revealed that this class of inhibitors formed a covalent bond with Cys797 in a distinct "DFG-in-C-helix-out" inactive EGFR conformation. Compound 19 displayed strong antiproliferative effects against EGFR mutant-driven nonsmall cell lung cancer (NSCLC) cell lines such as H1975, PC9, HCC827, and H3255 but not the wild-type EGFR expressing cells. In the H1975 and PC9 cell-inoculated xenograft mouse models, compound 19 exhibited dose-dependent tumor growth suppression efficacy without obvious toxicity. Compound 19 might be a potential drug candidate for EGFR mutant-driven NSCLC.

Topics: Animals; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Proliferation; Crystallography, X-Ray; ErbB Receptors; Female; Humans; Lung; Lung Neoplasms; Mice; Mice, Nude; Molecular Docking Simulation; Piperidines; Point Mutation; Protein Conformation; Protein Kinase Inhibitors; Rats, Sprague-Dawley

Mutant epidermal growth factor receptor (EGFR) is a major driver of non-small-cell lung cancer (NSCLC). Marketed first generation inhibitors, such as erlotinib, effect a transient beneficial response in EGFR mutant NSCLC patients before resistance mechanisms render these inhibitors ineffective. Secondary oncogenic EGFR mutations account for approximately 50% of relapses, the most common being the gatekeeper T790M substitution that renders existing therapies ineffective. The discovery of PF-06459988 (1), an irreversible pyrrolopyrimidine inhibitor of EGFR T790M mutants, was recently disclosed.1 Herein, we describe our continued efforts to achieve potency across EGFR oncogenic mutations and improved kinome selectivity, resulting in the discovery of clinical candidate PF-06747775 (21), which provides potent EGFR activity against the four common mutants (exon 19 deletion (Del), L858R, and double mutants T790M/L858R and T790M/Del), selectivity over wild-type EGFR, and desirable ADME properties. Compound 21 is currently being evaluated in phase-I clinical trials of mutant EGFR driven NSCLC.

Topics: Acrylamides; Animals; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Dogs; Drug Design; ErbB Receptors; Halogenation; Humans; Lung; Lung Neoplasms; Mice; Models, Molecular; Molecular Docking Simulation; Mutation; Protein Kinase Inhibitors; Pyrrolidines; Rats

Potential new EGFR

Topics: Animals; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Drug Resistance, Neoplasm; ErbB Receptors; Gefitinib; Humans; Lung; Lung Neoplasms; Mice; Models, Molecular; Morpholines; Point Mutation; Protein Kinase Inhibitors; Pyrimidines; Quinazolines; Xenograft Model Antitumor Assays

Reversible epidermal growth factor receptor (EGFR) inhibitors prompt a beneficial clinical response in non-small cell lung cancer patients who harbor activating mutations in EGFR. However, resistance mutations, particularly the gatekeeper mutation T790M, limit this efficacy. Here, we describe a structure-guided development of a series of covalent and mutant-selective EGFR inhibitors that effectively target the T790M mutant. The pyrazolopyrimidine-based core differs structurally from that of aminopyrimidine-based third-generation EGFR inhibitors and therefore constitutes a new set of inhibitors that target this mechanism of drug resistance. These inhibitors exhibited strong inhibitory effects toward EGFR kinase activity and excellent inhibition of cell growth in the drug-resistant cell line H1975, without significantly affecting EGFR wild-type cell lines. Additionally, we present the in vitro ADME/DMPK parameters for a subset of the inhibitors as well as in vivo pharmacokinetics in mice for a candidate with promising activity profile.

Topics: Animals; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Drug Resistance, Neoplasm; ErbB Receptors; Humans; Lung Neoplasms; Male; Mice; Molecular Docking Simulation; Point Mutation; Protein Kinase Inhibitors; Pyrazoles; Pyrimidines

Kinase inhibitors are important cancer therapeutics. Polypharmacology is commonly observed, requiring thorough target deconvolution to understand drug mechanism of action. Using chemical proteomics, we analyzed the target spectrum of 243 clinically evaluated kinase drugs. The data revealed previously unknown targets for established drugs, offered a perspective on the "druggable" kinome, highlighted (non)kinase off-targets, and suggested potential therapeutic applications. Integration of phosphoproteomic data refined drug-affected pathways, identified response markers, and strengthened rationale for combination treatments. We exemplify translational value by discovering SIK2 (salt-inducible kinase 2) inhibitors that modulate cytokine production in primary cells, by identifying drugs against the lung cancer survival marker MELK (maternal embryonic leucine zipper kinase), and by repurposing cabozantinib to treat FLT3-ITD-positive acute myeloid leukemia. This resource, available via the ProteomicsDB database, should facilitate basic, clinical, and drug discovery research and aid clinical decision-making.

Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Cytokines; Drug Discovery; fms-Like Tyrosine Kinase 3; Humans; Leukemia, Myeloid, Acute; Lung Neoplasms; Mice; Molecular Targeted Therapy; Protein Kinase Inhibitors; Protein Serine-Threonine Kinases; Proteomics; Xenograft Model Antitumor Assays

Topics: Acrylamides; Carcinoma, Non-Small-Cell Lung; Cataract; Cataract Extraction; Female; Follow-Up Studies; Humans; Lung Neoplasms; Male; Middle Aged; Pyrimidines

EGFR-mutated lung cancers account for a significant subgroup of non-small cell lung cancers overall. Third-generation EGFR tyrosine kinase inhibitors (TKI) are mutation-selective inhibitors with minimal effects on wild-type EGFR. Acquired resistance develops to these agents, however, the mechanisms are as yet uncharacterized. In this study, we report that the Src-AKT pathway contributes to acquired resistance to these TKI. In addition, amplification of EGFR wild-type alleles but not mutant alleles was sufficient to confer acquired resistance. These findings underscore the importance of signals from wild-type EGFR alleles in acquiring resistance to mutant-selective EGFR-TKI. Our data provide evidence of wild-type allele-mediated resistance, a novel concept of acquired resistance in response to mutation-selective inhibitor therapy in cancer treatment.

Topics: Acrylamides; Alleles; Animals; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cetuximab; Drug Resistance, Neoplasm; Epithelial-Mesenchymal Transition; ErbB Receptors; Exome; Female; Gene Amplification; Humans; Lung Neoplasms; Mice; Mice, Inbred BALB C; Protein Kinase Inhibitors; Pyrimidines; Random Allocation; Xenograft Model Antitumor Assays

First generation EGFR TKIs (gefitinib, erlotinib) provide significant clinical benefit for NSCLC cancer patients with oncogenic EGFR mutations. Ultimately, these patients' disease progresses, often driven by a second-site mutation in the EGFR kinase domain (T790M). Another liability of the first generation drugs is severe adverse events driven by inhibition of WT EGFR. As such, our goal was to develop a highly potent irreversible inhibitor with the largest selectivity ratio between the drug-resistant double mutants (L858R/T790M, Del/T790M) and WT EGFR. A unique approach to develop covalent inhibitors, optimization of reversible binding affinity, served as a cornerstone of this effort. PF-06459988 was discovered as a novel, third generation irreversible inhibitor, which demonstrates (i) high potency and specificity to the T790M-containing double mutant EGFRs, (ii) minimal intrinsic chemical reactivity of the electrophilic warhead, (iii) greatly reduced proteome reactivity relative to earlier irreversible EGFR inhibitors, and (iv) minimal activity against WT EGFR.

Topics: Carcinoma, Non-Small-Cell Lung; Dose-Response Relationship, Drug; Drug Discovery; ErbB Receptors; Humans; Lung Neoplasms; Models, Molecular; Molecular Structure; Mutant Proteins; Mutation; Protein Kinase Inhibitors; Pyrimidines; Pyrroles; Structure-Activity Relationship; Tumor Cells, Cultured

Over the past decade, first and second generation EGFR inhibitors have significantly improved outcomes for lung cancer patients with activating mutations in EGFR. However, both resistance through a secondary T790M mutation at the gatekeeper residue and dose-limiting toxicities from wild-type (WT) EGFR inhibition ultimately limit the full potential of these therapies to control mutant EGFR-driven tumors and new therapies are urgently needed. Herein, we describe our approach toward the discovery of 47 (EGF816, nazartinib), a novel, covalent mutant-selective EGFR inhibitor with equipotent activity on both oncogenic and T790M-resistant EGFR mutations. Through molecular docking studies we converted a mutant-selective high-throughput screening hit (7) into a number of targeted covalent EGFR inhibitors with equipotent activity across mutants EGFR and good WT-EGFR selectivity. We used an abbreviated in vivo efficacy study for prioritizing compounds with good tolerability and efficacy that ultimately led to the selection of 47 as the clinical candidate.

Topics: Animals; Antineoplastic Agents; Benzimidazoles; Carcinoma, Non-Small-Cell Lung; Cell Proliferation; Crystallography, X-Ray; Dose-Response Relationship, Drug; Drug Discovery; Drug Screening Assays, Antitumor; ErbB Receptors; Humans; Lung Neoplasms; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Models, Molecular; Molecular Conformation; Mutation; Neoplasms, Experimental; Nicotine; Protein Kinase Inhibitors; Rats; Rats, Wistar; Structure-Activity Relationship

Topics: Acrylamides; Adenocarcinoma; Antineoplastic Agents; Carcinoma, Squamous Cell; Cell Transformation, Neoplastic; ErbB Receptors; Fatal Outcome; Female; Humans; Lung Neoplasms; Middle Aged; Pyrimidines; Treatment Outcome

Mutant selective epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), such as rociletinib and AZD9291, are effective for tumors with T790M secondary mutation that become refractory to first-generation EGFR-TKI. However, acquired resistance to these prospective drugs is anticipated considering the high adaptability of cancer cells and the mechanisms remain largely obscure. Here, CNX-2006 (tool compound of rociletinib) resistant sublines were established by chronic exposure of HCC827EPR cells harboring exon 19 deletion and T790M to CNX-2006. Through the analyses of these resistant subclones, we identified two resistant mechanisms accompanied by MET amplification. One was bypass signaling by MET amplification in addition to T790M, which was inhibited by the combination of CNX-2006 and MET-TKI. Another was loss of amplified EGFR mutant allele including T790M while acquiring MET amplification. Interestingly, MET-TKI alone was able to overcome this resistance, suggesting that oncogenic dependence completely shifted from EGFR to MET. We propose describing this phenomenon as an "oncogene swap." Furthermore, we analyzed multiple lesions from a patient who died of acquired resistance to gefitinib, then found a clinical example of an oncogene swap in which the EGFR mutation was lost and a MET gene copy was gained. In conclusion, an "oncogene swap" from EGFR to MET is a novel resistant mechanism to the EGFR-TKI. This novel mechanism should be considered in order to avoid futile inhibition of the original oncogene.

Topics: Acrylamides; Cell Line, Tumor; Drug Resistance, Neoplasm; ErbB Receptors; Gefitinib; Humans; Lung Neoplasms; Mutation; Oncogenes; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-met; Pyrimidines; Quinazolines

To identify novel mechanisms of resistance to third-generation EGFR inhibitors in patients with lung adenocarcinoma that progressed under therapy with either AZD9291 or rociletinib (CO-1686).. We analyzed tumor biopsies from seven patients obtained before, during, and/or after treatment with AZD9291 or rociletinib (CO-1686). Targeted sequencing and FISH analyses were performed, and the relevance of candidate genes was functionally assessed in in vitro models.

Topics: Acrylamides; Adenocarcinoma; Adenocarcinoma of Lung; Aged; Aniline Compounds; Antineoplastic Agents; Drug Resistance, Neoplasm; ErbB Receptors; Female; Humans; Lung Neoplasms; Male; Middle Aged; Pyrimidines

Circulating tumour DNA (ctDNA) analysis facilitates studies of tumour heterogeneity. Here we employ CAPP-Seq ctDNA analysis to study resistance mechanisms in 43 non-small cell lung cancer (NSCLC) patients treated with the third-generation epidermal growth factor receptor (EGFR) inhibitor rociletinib. We observe multiple resistance mechanisms in 46% of patients after treatment with first-line inhibitors, indicating frequent intra-patient heterogeneity. Rociletinib resistance recurrently involves MET, EGFR, PIK3CA, ERRB2, KRAS and RB1. We describe a novel EGFR L798I mutation and find that EGFR C797S, which arises in ∼33% of patients after osimertinib treatment, occurs in <3% after rociletinib. Increased MET copy number is the most frequent rociletinib resistance mechanism in this cohort and patients with multiple pre-existing mechanisms (T790M and MET) experience inferior responses. Similarly, rociletinib-resistant xenografts develop MET amplification that can be overcome with the MET inhibitor crizotinib. These results underscore the importance of tumour heterogeneity in NSCLC and the utility of ctDNA-based resistance mechanism assessment.

Topics: Acrylamides; Carcinoma, Non-Small-Cell Lung; Circulating Tumor DNA; Cohort Studies; Crizotinib; Drug Resistance, Neoplasm; ErbB Receptors; Gene Amplification; Gene Dosage; Genetic Heterogeneity; Humans; Lung Neoplasms; Mutation; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-met; Pyrazoles; Pyridines; Pyrimidines; Xenograft Model Antitumor Assays

Approximately one-third of patients with non-small cell lung cancer (NSCLC) harboring tumors with EGFR-tyrosine kinase inhibitor (TKI)-sensitizing mutations (EGFRm) experience disease progression during treatment due to brain metastases. Despite anecdotal reports of EGFR-TKIs providing benefit in some patients with EGFRm NSCLC brain metastases, there is a clinical need for novel EGFR-TKIs with improved efficacy against brain lesions.. We performed preclinical assessments of brain penetration and activity of osimertinib (AZD9291), an oral, potent, irreversible EGFR-TKI selective for EGFRm and T790M resistance mutations, and other EGFR-TKIs in various animal models of EGFR-mutant NSCLC brain metastases. We also present case reports of previously treated patients with EGFRm-advanced NSCLC and brain metastases who received osimertinib in the phase I/II AURA study (NCT01802632).. Osimertinib demonstrated greater penetration of the mouse blood-brain barrier than gefitinib, rociletinib (CO-1686), or afatinib, and at clinically relevant doses induced sustained tumor regression in an EGFRm PC9 mouse brain metastases model; rociletinib did not achieve tumor regression. Under positron emission tomography micro-dosing conditions, [. Osimertinib may represent a clinically significant treatment option for patients with EGFRm NSCLC and brain metastases. Further investigation of osimertinib in this patient population is ongoing. Clin Cancer Res; 22(20); 5130-40. ©2016 AACR.

Topics: Acrylamides; Afatinib; Aniline Compounds; Animals; Antineoplastic Agents; Biological Transport; Blood-Brain Barrier; Brain Neoplasms; Caco-2 Cells; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Disease Progression; Dogs; Drug Evaluation, Preclinical; Drug Resistance, Neoplasm; ErbB Receptors; Female; Gefitinib; Humans; Lung Neoplasms; Madin Darby Canine Kidney Cells; Male; Mice; Mice, SCID; Middle Aged; Piperazines; Protein Kinase Inhibitors; Pyrimidines; Quinazolines; Rats; Xenograft Model Antitumor Assays

The 3rd generation epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs; e.g., AZD9291), which selectively and irreversibly inhibit EGFR activating and T790M mutants, represent very promising therapeutic options for patients with non-small cell lung cancer (NSCLC) that has become resistant to 1st generation EGFR-TKIs due to T790M mutation. However, eventual resistance to the 3rd generation EGFR-TKIs has already been described in the clinic, resulting in disease progression. Therefore, there is a great challenge and urgent need to understand how this resistance occurs and to develop effective strategies to delay or overcome the resistance. The current study has demonstrated that Met amplification and hyperactivation is a resistance mechanism to both 1st and 3rd generation EGFR-TKIs since both erlotinib- and AZD9291-resistant HCC827 cell lines possessed amplified Met gene and hyperactivated Met, and were cross-resistant to AZD9291 or erlotinib. Met inhibition overcame the resistance of these cell lines to AZD9291 both in vitro and in vivo, including enhancement of apoptosis or G1 cell cycle arrest. Hence, we suggest that Met inhibition is also an effective strategy to overcome resistance of certain EGFR-mutated NSCLCs with Met amplification to AZD9291, warranting the further clinical validation of our findings.

Topics: Acrylamides; Aniline Compounds; Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Proliferation; Crizotinib; Dose-Response Relationship, Drug; Drug Resistance, Neoplasm; ErbB Receptors; Erlotinib Hydrochloride; Female; G1 Phase Cell Cycle Checkpoints; Gene Amplification; Gene Expression Regulation, Neoplastic; Humans; Lung Neoplasms; Mice, Nude; Molecular Targeted Therapy; Mutation; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-met; Pyrazoles; Pyridines; Pyrimidines; RNA Interference; Signal Transduction; Time Factors; Transfection; Tumor Burden; Xenograft Model Antitumor Assays

We report 6 patients who developed rapidly progressive hypermature cataracts after starting treatment with rociletinib, a non-small-cell lung cancer therapy with known side effects of hyperglycemia, fatigue, and prolonged QT. Early cataract detection and surgery may prevent complications during future cataract removal. Although rociletinib development has been suspended, there are patients who have been treated and will continue to be treated with this medication based on their physician's judgment. These physicians should know about the potential for rapid vision loss due to cataracts as a manageable side effect.. Neither author has a financial or proprietary interest in any material or method mentioned.

Topics: Acrylamides; Aged; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Cataract; Cataract Extraction; Humans; Lens Implantation, Intraocular; Lung Neoplasms; Middle Aged; Pyrimidines

Receptor tyrosine kinases represent one of the prime targets in cancer therapy, as the dysregulation of these elementary transducers of extracellular signals, like the epidermal growth factor receptor (EGFR), contributes to the onset of cancer, such as non-small cell lung cancer (NSCLC). Strong efforts were directed to the development of irreversible inhibitors and led to compound CO-1686, which takes advantage of increased residence time at EGFR by alkylating Cys797 and thereby preventing toxic effects. Here, we present a structure-based approach, rationalized by subsequent computational analysis of conformational ligand ensembles in solution, to design novel and irreversible EGFR inhibitors based on a screening hit that was identified in a phenotype screen of 80 NSCLC cell lines against approximately 1500 compounds. Using protein X-ray crystallography, we deciphered the binding mode in engineered cSrc (T338M/S345C), a validated model system for EGFR-T790M, which constituted the basis for further rational design approaches. Chemical synthesis led to further compound collections that revealed increased biochemical potency and, in part, selectivity toward mutated (L858R and L858R/T790M) vs nonmutated EGFR. Further cell-based and kinetic studies were performed to substantiate our initial findings. Utilizing proteolytic digestion and nano-LC-MS/MS analysis, we confirmed the alkylation of Cys797.

Topics: Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Membrane Permeability; Crystallography, X-Ray; Databases, Chemical; Drug Design; Drug Resistance, Neoplasm; ErbB Receptors; Humans; Kinetics; Lung Neoplasms; Models, Molecular; Molecular Conformation; Mutation; Pyrazoles; Pyrimidines; Quinazolines; Small Molecule Libraries; Solubility; src-Family Kinases; Structure-Activity Relationship

Topics: Acrylamides; Carcinoma, Non-Small-Cell Lung; Clinical Trials as Topic; ErbB Receptors; Humans; Lung Neoplasms; Protein Kinase Inhibitors; Pyrimidines

Rociletinib is a third-generation EGFR inhibitor active in lung cancers with T790M, the gatekeeper mutation underlying most first-generation EGFR drug resistance. We biopsied patients at rociletinib progression to explore resistance mechanisms. Among 12 patients with T790M-positive cancers at rociletinib initiation, six had T790-wild-type rociletinib-resistant biopsies. Two T790-wild-type cancers underwent small cell lung cancer transformation; three T790M-positive cancers acquired EGFR amplification. We documented T790-wild-type and T790M-positive clones coexisting within a single pre-rociletinib biopsy. The pretreatment fraction of T790M-positive cells affected response to rociletinib. Longitudinal circulating tumor DNA (ctDNA) analysis revealed an increase in plasma EGFR-activating mutation, and T790M heralded rociletinib resistance in some patients, whereas in others the activating mutation increased but T790M remained suppressed. Together, these findings demonstrate the role of tumor heterogeneity when therapies targeting a singular resistance mechanism are used. To further improve outcomes, combination regimens that also target T790-wild-type clones are required.. This report documents that half of T790M-positive EGFR-mutant lung cancers treated with rociletinib are T790-wild-type upon progression, suggesting that T790-wild-type clones can emerge as the dominant source of resistance. We show that tumor heterogeneity has important clinical implications and that plasma ctDNA analyses can sometimes predict emerging resistance mechanisms.

Topics: Acrylamides; Cell Line, Tumor; DNA, Neoplasm; Drug Resistance, Neoplasm; ErbB Receptors; Gene Amplification; Gene Expression Regulation, Neoplastic; Genetic Heterogeneity; Humans; Lung Neoplasms; Mutation; Prospective Studies; Protein Kinase Inhibitors; Pyrimidines; Small Cell Lung Carcinoma

The clinical efficacy of EGFR tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC) harbouring activating EGFR mutations is limited by the emergence of acquired resistance, mostly ascribed to the secondary EGFR-T790M mutation. Selective EGFR-T790M inhibitors have been proposed as a new, extremely relevant therapeutic approach. Here, we demonstrate that the novel irreversible EGFR-TKI CNX-2006, a structural analog of CO-1686, currently tested in a phase-1/2 trial, is active against in vitro and in vivo NSCLC models expressing mutant EGFR, with minimal effect on the wild-type receptor. By integration of genetic and functional analyses in isogenic cell pairs we provide evidence of the crucial role played by NF-κB1 in driving CNX-2006 acquired resistance and show that NF-κB activation may replace the oncogenic EGFR signaling in NSCLC when effective and persistent inhibition of the target is achieved in the presence of the T790M mutation. In this context, we demonstrate that the sole, either genetic or pharmacologic, inhibition of NF-κB is sufficient to reduce the viability of cells that adapted to EGFR-TKIs. Overall, our findings support the rational inhibition of members of the NF-κB pathway as a promising therapeutic option for patients who progress after treatment with novel mutant-selective EGFR-TKIs.

Topics: Acrylamides; Animals; Antineoplastic Agents; Azetidines; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Drug Resistance, Neoplasm; Enzyme-Linked Immunosorbent Assay; ErbB Receptors; Humans; Lung Neoplasms; Mice; NF-kappa B; Protein Kinase Inhibitors; Pyrimidines; RNA, Small Interfering; Transfection; Xenograft Model Antitumor Assays

Patients with non-small cell lung cancer (NSCLC) with activating EGF receptor (EGFR) mutations initially respond to first-generation reversible EGFR tyrosine kinase inhibitors. However, clinical efficacy is limited by acquired resistance, frequently driven by the EGFR(T790M) mutation. CO-1686 is a novel, irreversible, and orally delivered kinase inhibitor that specifically targets the mutant forms of EGFR, including T790M, while exhibiting minimal activity toward the wild-type (WT) receptor. Oral administration of CO-1686 as single agent induces tumor regression in EGFR-mutated NSCLC tumor xenograft and transgenic models. Minimal activity of CO-1686 against the WT EGFR receptor was observed. In NSCLC cells with acquired resistance to CO-1686 in vitro, there was no evidence of additional mutations or amplification of the EGFR gene, but resistant cells exhibited signs of epithelial-mesenchymal transition and demonstrated increased sensitivity to AKT inhibitors. These results suggest that CO-1686 may offer a novel therapeutic option for patients with mutant EGFR NSCLC.. We report the preclinical development of a novel covalent inhibitor, CO-1686, that irreversibly and selectively inhibits mutant EGFR, in particular the T790M drug-resistance mutation, in NSCLC models. CO-1686 is the fi rst drug of its class in clinical development for the treatment of T790M-positive NSCLC, potentially offering potent inhibition of mutant EGFR while avoiding the on-target toxicity observed with inhibition of the WT EGFR.

Topics: Acrylamides; Administration, Oral; Animals; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Proliferation; Drug Resistance, Neoplasm; Drug Screening Assays, Antitumor; Epithelial-Mesenchymal Transition; ErbB Receptors; Female; HEK293 Cells; Humans; Lung Neoplasms; Mice; Mice, Inbred BALB C; Mice, Nude; Mice, Transgenic; Molecular Targeted Therapy; Mutant Proteins; Protein Kinase Inhibitors; Pyrimidines; Xenograft Model Antitumor Assays