Jing Sun

Bio: Jing Sun is an academic researcher from Vanderbilt University. The author has contributed to research in topics: T790M & EGFR inhibitors. The author has an hindex of 5, co-authored 5 publications receiving 1865 citations. Previous affiliations of Jing Sun include University of Tennessee Health Science Center.

AZD9291, an irreversible EGFR TKI, overcomes T790M-mediated resistance to EGFR inhibitors in lung cancer

Abstract: First-generation EGFR tyrosine kinase inhibitors (EGFR TKI) provide significant clinical benefit in patients with advanced EGFR-mutant (EGFRm+) non–small cell lung cancer (NSCLC). Patients ultimately develop disease progression, often driven by acquisition of a second T790M EGFR TKI resistance mutation. AZD9291 is a novel oral, potent, and selective third-generation irreversible inhibitor of both EGFRm+ sensitizing and T790M resistance mutants that spares wild-type EGFR. This mono-anilino–pyrimidine compound is structurally distinct from other third-generation EGFR TKIs and offers a pharmacologically differentiated profile from earlier generation EGFR TKIs. Preclinically, the drug potently inhibits signaling pathways and cellular growth in both EGFRm+ and EGFRm+/T790M+ mutant cell lines in vitro, with lower activity against wild-type EGFR lines, translating into profound and sustained tumor regression in EGFR-mutant tumor xenograft and transgenic models. The treatment of 2 patients with advanced EGFRm+ T790M+ NSCLC is described as proof of principle. Significance: We report the development of a novel structurally distinct third-generation EGFR TKI, AZD9291, that irreversibly and selectively targets both sensitizing and resistant T790M+ mutant EGFR while harboring less activity toward wild-type EGFR. AZD9291 is showing promising responses in a phase I trial even at the first-dose level, with first published clinical proof-of-principle validation being presented. Cancer Discov; 4(9); 1046–61. ©2014 AACR. This article is highlighted in the In This Issue feature, p. 973

Discovery of a Mutant-Selective Covalent Inhibitor of EGFR that Overcomes T790M-Mediated Resistance in NSCLC

Abstract: Non-small cell lung cancer (NSCLC) patients with activating epidermal growth factor 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 towards 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 (EMT) and demonstrated increased sensitivity to AKT inhibitors. These results suggest CO-1686 may offer a novel therapeutic option for patients with mutant EGFR NSCLC.

NF-κB drives acquired resistance to a novel mutant-selective EGFR inhibitor

Abstract: // Elena Galvani 1 , Jing Sun 2 , Leticia G. Leon 3 , Rocco Sciarrillo 1,4 , Ravi S. Narayan 5 , Robert Tjin Tham Sjin 6 , Kwangho Lee 6 , Kadoaki Ohashi 2 , Danielle A.M. Heideman 7 , Roberta R. Alfieri 8 , Guus J. Heynen 9 , Rene Bernards 9 , Egbert F. Smit 10 , William Pao 2 , Godefridus J. Peters 1 and Elisa Giovannetti 1,11 1 Department Medical Oncology, VU University Medical Center, Amsterdam, The Netherlands 2 Division of Hematology/Oncology, Department of Medicine, Vanderbilt University School of Medicine and Vanderbilt-Ingram Cancer Center, Nashville, TN, USA 3 Instituto de Tecnologias Biomedicas, Center for Biomedical Research of the Canary Islands, University of La Laguna, Tenerife, Spain 4 Department Hematology, VU University Medical Center, Amsterdam, The Netherlands 5 Department Radiation Oncology, VU University Medical Center, Amsterdam, The Netherlands 6 Celgene Avilomics Research, Bedford, MA, USA 7 Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands 8 Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy 9 Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, The Netherlands 10 Department of Pulmonary Diseases, VU University Medical Center, Amsterdam, The Netherlands 11 Cancer Pharmacology Lab, AIRC Start-Up Unit, DIPINT, University of Pisa, Pisa, Italy Correspondence to: Elisa Giovannetti, email: // Keywords : drug-resistance, EGFR-T790M, NSCLC, NF-κB, EMT Received : January 10, 2015 Accepted : April 08, 2015 Published : April 29, 2015 Abstract 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.

Abstract 2101A: CNX-2006, a novel irreversible epidermal growth factor receptor (EGFR) inhibitor, selectively inhibits EGFR T790M and fails to induce T790M-mediated resistancein vitro.

Abstract: Introduction: EGFR mutant lung cancers are highly sensitive to first generation EGFR tyrosine kinase inhibitors (TKIs; gefitinib and erlotinib), but resistance eventually develops. In the majority of patients, such acquired resistance (AR) is mediated by a second-site T790M “gatekeeper” mutation. Second generation TKIs (e.g. afatinib, dacomitinib, neratinib) are more potent but have minimal efficacy as single agents in patients with AR. Notably, second generation TKIs still inhibit the wild type receptor which limits dose escalation, and similar to gefitinib/erlotinib, they still select for T790M-mediated resistance in vitro due to selectivity for drug-sensitive mutations (exon 19 deletions and L858R) compared to T790M. In this study, we characterize the inhibitory properties of CNX-2006, a novel irreversible EGFR TKI developed to inhibit specifically T790M. CNX-2006 is the prototype for CO-1686 which is currently in phase I clinical trials for the treatment of EGFR-mutant lung cancer. Methods and Results: CNX-2006 potency was assessed via multiple methods: i) surrogate kinase assays using immunoblotting of lysates from 293 cells transfected with cDNAs encoding various EGFR mutations and treated with drug, ii) growth inhibition assays using various erlotinib-resistant EGFR mutant cell lines or engineered Ba/F3 cells, and iii) H1975 xenografts expressing EGFR(L858R/T790M). CNX-2006 exhibited specificity and potent in vitro and in vivo activity against T790M. The drug also showed activity against uncommon EGFR mutations including G719S, L861Q, an exon 19 insertion mutant (I744-K745insKIPVAI), and T854A, but not an exon 20 insertion (H773-V774HVdup). In an in vitro resistance model, CNX-2006 significantly inhibited the emergence of resistant cells compared with erlotinib (1/24 vs 11/24, p = 0.0013). Chronic exposure to escalating doses of CNX-2006 failed to select for and/or enhance T790M-mediated resistance using PC-9 or HCC827 cells (both harboring exon 19 deletions), or PC-9/ER and HCC827/ER cells with existing T790M and resistance to erlotinib. In PC-9 and HCC827 cells with acquired resistance to CNX-2006, MET amplification or other known mutations in the RAS/MEK/ERK signaling pathway have not been detected. Conclusions: These results demonstrate that the profile of CNX-2006 is different from first and second generation EGFR TKIs. CNX-2006 selectively targets T790M, shows activity against other common and uncommon EGFR mutations, and does not select for resistance mediated by T790M. Additional studies are ongoing to elucidate mechanisms of acquired resistance to CNX-2006. Citation Format: Kadoaki Ohashi, Kenichi Suda, Jing Sun, Yumei Pan, Annette O. Walter, Alex Dubrovskiy, Robert Tjin, Tetsuya Mitsudomi, William Pao. CNX-2006, a novel irreversible epidermal growth factor receptor (EGFR) inhibitor, selectively inhibits EGFR T790M and fails to induce T790M-mediated resistance in vitro. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2101A. doi:10.1158/1538-7445.AM2013-2101A

Osimertinib in Untreated EGFR-Mutated Advanced Non–Small-Cell Lung Cancer

Abstract: BackgroundOsimertinib is an oral, third-generation, irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) that selectively inhibits both EGFR-TKI–sensitizing and EGFR T790M resistance mutations. We compared osimertinib with standard EGFR-TKIs in patients with previously untreated, EGFR mutation–positive advanced non–small-cell lung cancer (NSCLC). MethodsIn this double-blind, phase 3 trial, we randomly assigned 556 patients with previously untreated, EGFR mutation–positive (exon 19 deletion or L858R) advanced NSCLC in a 1:1 ratio to receive either osimertinib (at a dose of 80 mg once daily) or a standard EGFR-TKI (gefitinib at a dose of 250 mg once daily or erlotinib at a dose of 150 mg once daily). The primary end point was investigator-assessed progression-free survival. ResultsThe median progression-free survival was significantly longer with osimertinib than with standard EGFR-TKIs (18.9 months vs. 10.2 months; hazard ratio for disease progression or death, 0.46; 95% confi...

Phase III study of afatinib or cisplatin plus pemetrexed in patients with metastatic lung adenocarcinoma with EGFR mutations

Abstract: Purpose The LUX-Lung 3 study investigated the efficacy of chemotherapy compared with afatinib, a selective, orally bioavailable ErbB family blocker that irreversibly blocks signaling from epidermal growth factor receptor (EGFR/ErbB1), human epidermal growth factor receptor 2 (HER2/ErbB2), and ErbB4 and has wide-spectrum preclinical activity against EGFR mutations. A phase II study of afatinib in EGFR mutation-positive lung adenocarcinoma demonstrated high response rates and progression-free survival (PFS). Patients and Methods In this phase III study, eligible patients with stage IIIB/IV lung adenocarcinoma were screened for EGFR mutations. Mutation-positive patients were stratified by mutation type (exon 19 deletion, L858R, or other) and race (Asian or non-Asian) before two-to-one random assignment to 40 mg afatinib per day or up to six cycles of cisplatin plus pemetrexed chemotherapy at standard doses every 21 days. The primary end point was PFS by independent review. Secondary end points included tumor response, overall survival, adverse events, and patient-reported outcomes (PROs). Results A total of 1,269 patients were screened, and 345 were randomly assigned to treatment. Median PFS was 11.1 months for afatinib and 6.9 months for chemotherapy (hazard ratio [HR], 0.58; 95% CI, 0.43 to 0.78; P = .001). Median PFS among those with exon 19 deletions and L858R EGFR mutations (n = 308) was 13.6 months for afatinib and 6.9 months for chemotherapy (HR, 0.47; 95% CI, 0.34 to 0.65; P = .001). The most common treatmentrelated adverse events were diarrhea, rash/acne, and stomatitis for afatinib and nausea, fatigue, and decreased appetite for chemotherapy. PROs favored afatinib, with better control of cough, dyspnea, and pain. Conclusion Afatinib is associated with prolongation of PFS when compared with standard doublet chemotherapy in patients with advanced lung adenocarcinoma and EGFR mutations.

Osimertinib or Platinum-Pemetrexed in EGFR T790M-Positive Lung Cancer.

Abstract: BackgroundOsimertinib is an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) that is selective for both EGFR-TKI sensitizing and T790M resistance mutations in patients with non–small-cell lung cancer. The efficacy of osimertinib as compared with platinum-based therapy plus pemetrexed in such patients is unknown. MethodsIn this randomized, international, open-label, phase 3 trial, we assigned 419 patients with T790M-positive advanced non–small-cell lung cancer, who had disease progression after first-line EGFR-TKI therapy, in a 2:1 ratio to receive either oral osimertinib (at a dose of 80 mg once daily) or intravenous pemetrexed (500 mg per square meter of body-surface area) plus either carboplatin (target area under the curve, 5 [AUC5]) or cisplatin (75 mg per square meter) every 3 weeks for up to six cycles; maintenance pemetrexed was allowed. In all the patients, disease had progressed during receipt of first-line EGFR-TKI therapy. The primary end point was investigator-assessed pro...

AZD9291 in EGFR Inhibitor–Resistant Non–Small-Cell Lung Cancer

Abstract: Background The EGFR T790M mutation is the most common mechanism of drug resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors in patients who have lung cancer with an EGFR mutation (EGFR-mutated lung cancer). In preclinical models, the EGFR inhibitor AZD9291 has been shown to be effective against both EGFR tyrosine kinase inhibitor-sensitizing and T790M resistance mutations. Methods We administered AZD9291 at doses of 20 to 240 mg once daily in patients with advanced lung cancer who had radiologically documented disease progression after previous treatment with EGFR tyrosine kinase inhibitors. The study included dose-escalation cohorts and dose-expansion cohorts. In the expansion cohorts, prestudy tumor biopsies were required for central determination of EGFR T790M status. Patients were assessed for safety, pharmacokinetics, and efficacy. Results A total of 253 patients were treated. Among 31 patients enrolled in the dose-escalation cohorts, no dose-limiting toxic effects occurred at the doses evaluated. An additional 222 patients were treated in five expansion cohorts. The most common all-cause adverse events were diarrhea, rash, nausea, and decreased appetite. The overall objective tumor response rate was 51% (95% confidence interval [CI], 45 to 58). Among 127 patients with centrally confirmed EGFR T790M who could be evaluated for response, the response rate was 61% (95% CI, 52 to 70). In contrast, among 61 patients without centrally detectable EGFR T790M who could be evaluated for response, the response rate was 21% (95% CI, 12 to 34). The median progression-free survival was 9.6 months (95% CI, 8.3 to not reached) in EGFR T790M-positive patients and 2.8 months (95% CI, 2.1 to 4.3) in EGFR T790M-negative patients. Conclusions AZD9291 was highly active in patients with lung cancer with the EGFR T790M mutation who had had disease progression during prior therapy with EGFR tyrosine kinase inhibitors. (Funded by AstraZeneca; ClinicalTrials.gov number, NCT01802632.).