Golidocitinib, a selective JAK1 tyrosine-kinase inhibitor, in patients with refractory or relapsed peripheral T-cell lymphoma (JACKPOT8 Part B): a single-arm, multinational, phase 2 study.

BACKGROUND: Golidocitinib, a selective JAK1 tyrosine-kinase inhibitor, has shown encouraging anti-tumour activity in heavily pre-treated patients with relapsed or refractory peripheral T-cell lymphoma in a phase 1 study (JACKPOT8 Part A). Here, we report the full analysis of a phase 2 study, in which we assessed the anti-tumour activity of golidocitinib in a large multinational cohort of patients. METHODS: We did a single-arm, multinational, phase 2 trial (JACKPOT8 Part B) in 49 centres in Australia, China, South Korea, and the USA. Eligible patients were adults (aged ≥18 years) with relapsed or refractory peripheral T-cell lymphoma who had received at least one previous line of systemic therapy and an Eastern Cooperative Oncology Group performance status of 0-2. Patients were given oral golidocitinib 150 mg once daily until disease progression or other discontinuation criteria were met. The primary endpoint was the CT-based objective response rate, assessed by an independent review committee (IRC) per Lugano 2014 classification. The activity analysis set included all patients who received at least one dose and whose pathological diagnosis of peripheral T-cell lymphoma had been retrospectively confirmed by a central laboratory and who had at least one measurable lesion at baseline assessed by IRC. The safety analysis set included all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, NCT04105010, and is closed to accrual and follow-up is ongoing. FINDINGS: Between Feb 26, 2021, and Oct 12, 2022, we assessed 161 patients for eligibility, of whom 104 (65%) were enrolled and received at least one dose of study drug; the activity analysis set included 88 (85%) patients (median age 58 years [IQR 51-67], 57 [65%] of 88 were male, 31 [35%] were female, and 83 [94%] were Asian). As of data cutoff (Aug 31, 2023; median follow-up was 13·3 months [IQR 4·9-18·4]), per IRC assessment, the objective response rate was 44·3% (95% CI 33·7-55·3; 39 of 88 patients, p<0·0001), with 21 (24%) patients having a complete response and 18 (20%) having a partial response. In the safety analysis set, 61 (59%) of 104 patients had grade 3-4 drug-related treatment-emergent adverse events. The most common grade 3-4 drug-related treatment-emergent adverse events were neutrophil count decreased (30 [29%]), white blood cell count decreased (27 [26%]), lymphocyte count decreased (22 [21%]), and platelet count decreased (21 [20%]), which were clinically manageable and reversible. 25 (24%) patients had treatment-related serious adverse events. Deaths due to treatment-emergent adverse events occurred in three (3%) patients: two (2%) due to pneumonia (one case with fungal infection [related to golidocitinib] and another one with COVID-19 infection) and one (1%) due to confusional state. INTERPRETATION: In this phase 2 study, golidocitinib showed a favourable benefit-risk profile in treating relapsed or refractory peripheral T-cell lymphoma. The results of this study warrant further randomised clinical studies to confirm activity and assess efficacy in this population. FUNDING: Dizal Pharmaceutical.

Sunvozertinib for patients in China with platinum-pretreated locally advanced or metastatic non-small-cell lung cancer and EGFR exon 20 insertion mutation (WU-KONG6): single-arm, open-label, multicentre, phase 2 trial.

BACKGROUND: Sunvozertinib is an oral, irreversible, and selective tyrosine kinase inhibitor that has a favourable safety profile and encouraging antitumour activity, as shown in phase 1 studies of patients with heavily pretreated non-small cell lung cancer (NSCLC) with EGFR exon 20 insertion mutation (exon20ins). We aimed to assess the antitumour efficacy of sunvozertinib in patients with platinum-pretreated locally advanced or metastatic NSCLC with EGFR exon20ins. METHODS: WU-KONG6 is a single-group, open-label, multicentre phase 2 trial of sunvozertinib monotherapy, conducted across 37 medical centres in China. We enrolled adult patients with pathologically or cytologically confirmed locally advanced or metastatic NSCLC whose tumour tissue carried an EGFR exon20ins mutation. All patients had received at least one line of previous systemic therapy, with at least one line containing platinum-based chemotherapy. The primary endpoint was objective response rate (ORR), as assessed by the independent review committee. The ORR was defined as the percentage of patients who achieved complete or partial response, confirmed by two separate assessments with at least 4-week time interval, until disease progression or initiation of any new anti-cancer therapy. Enrolled patients received sunvozertinib 300 mg once daily until meeting discontinuation criteria per the protocol. Patients who received at least one dose of treatment and were evaluable for efficacy analysis were included in the primary analysis, and all patients who received at least one dose of treatment were included in the safety analysis. This study is registered with ChinaDrugTrials.org, CTR20211009, and ClinicalTrials.gov, NCT05712902, and efficacy and safety follow-up are ongoing. FINDINGS: Between July 19, 2021, and May 6, 2022, 104 patients were enrolled. At data cutoff (Oct 17, 2022), the last enrolled patient had been followed up for about 6 months. Among 97 patients evaluable for efficacy analysis, 59 (61%) patients achieved tumour response, with a confirmed ORR of 61% (95% CI 50-71). All tumour responses were partial responses. Tumour responses were observed irrespective of age, sex, smoking history, EGFR exon20ins subtypes, brain metastasis at baseline, previous lines of therapy, and history of onco-immunotherapy. In total, 19 death events occurred over a median follow-up period of 7·6 months (IQR 6·1-9·4). Sunvozertinib was well tolerated at 300 mg once daily. The most common grade 3 or worse treatment-related adverse events were blood creatine phosphokinase increased (18 [17%] of 104), diarrhoea (eight [8%]), and anaemia (six [6%]). The most common serious treatment-related adverse events were interstitial lung disease (five [5%] of 104), anaemia (three [3%]), vomiting (two [2%]), nausea (two [2%]) and pneumonia (two [2%]). INTERPRETATION: In this phase 2 study, sunvozertinib demonstrated antitumour efficacy in patients with platinum-based chemotherapy pretreated NSCLC with EGFR exon20ins, with a manageable safety profile. A multinational randomised, phase 3 study of sunvozertinib versus platinum-doublet chemotherapy in EGFR exon20ins NSCLC is ongoing (NCT05668988). FUNDING: Dizal Pharmaceutical.

Pharmacokinetic characteristics of golidocitinib, a highly selective JAK1 inhibitor, in healthy adult participants.

Background: Golidocitinib is an orally available, potent and highly selective JAK (Janus kinase)-1 inhibitor of JAK/STAT3 signaling under clinical development for the treatment of cancer and autoimmune diseases. The objectives of the two reported studies were to investigate the pharmacokinetics (PK), safety, and tolerability of golidocitinib in healthy Chinese participants as compared to those healthy Western participants, as well as the food effect exploration. Methods: Two phase I studies (JACKPOT2 and JACKPOT3) were conducted in USA and China, respectively. In JACKPOT2 study, participants were randomized into placebo or golidocitinib arm in single-ascending dose cohorts (5 - 150 mg) and multiple-ascending dose cohorts (25 - 100 mg, once daily) for 14 days. In the food effect cohort, golidocitinib (50 mg) was administrated shortly after a high-fat meal (fed conditions) as compared to under fasting conditions. In JACKPOT3 study conducted in China, participants were randomized to placebo or golidocitinib arm in single-ascending dose cohorts (25 - 150 mg). Results: Exposure of golidocitinib generally increased in a dose-proportional manner across a dose range of 5 mg to 150 mg (single dose) and 25 mg to 100 mg (once daily). High-fat food did not alter the PK of golidocitinib with statistical significance. Low plasma clearance and extensive volume of distribution characterizes PK of golidoctinib, and long half-life across the dose levels supported once daily dosing. The inter-ethnic difference in primary PK parameters was evaluated. The result suggested slightly higher peak plasma concentrations (Cmax) but comparable area under the plasma concentration-time curve (AUC) was observed in Asian (Chinese) subjects as compared to Caucasian and/or Black subjects, while it was not considered clinically relevant. Golidocitinib was well tolerated without Common Terminology Criteria for Adverse Events (CTCAE) grade 3 or higher drug-related treatment emergent adverse events (TEAE) reported. Conclusion: No noticeable inter-ethnic difference was observed among Asian, Black, and Caucasian healthy subjects in anticipation of the favorable PK properties of golidocitinib. The effect of food on the bioavailability of golidocitinib was minor following a single oral administration of 50 mg. These data guided to use the same dose and regimen for multinational clinical development. Clinical trial registrations: https://clinicaltrials.gov/ct2/show/NCT03728023?term=NCT03728023&draw=2&rank=1, identifier (NCT03728023); http://www.chinadrugtrials.org.cn/clinicaltrials.searchlistdetail.dhtml, identifier (CTR20191011).

Overcoming high level adenosine-mediated immunosuppression by DZD2269, a potent and selective A2aR antagonist.

BACKGROUND: Adenosine is a potent immunosuppressant whose levels in the tumor microenvironment (TME) are often much higher than those in normal tissues. Binding of adenosine to its receptor A2aR activates a cascade of genes and leads to immunosuppression. In addition, immune checkpoint blockage markedly increases A2aR expression in T cells, which could dampen their anti-tumor response. Several A2aR antagonists are under clinical development, but with limited clinical benefit reported so far. These A2aR antagonists showed much diminished activity at high adenosine levels found in TME, which may explain their clinical underperformance. We report the discovery and early clinical development of DZD2269, a novel A2aR antagonist which can fully block A2aR mediated immunosuppression commonly found in TME. Adenosine stimulates phosphorylation of cyclic AMP response element binding protein (CREB) in T cells and inhibits anti-tumor cytokine secretion in PBMCs in a dose-dependent manner. DZD2269 was able to reverse the immunosuppression induced by high concentrations of adenosine, as demonstrated by inhibiting CREB phosphorylation in T cells, restoring Th1 cytokine secretion in PBMCs, and stimulating dendritic cells (DCs) maturation. As a single agent, DZD2269 showed anti-tumor growth in multiple syngeneic mouse tumor models, and more profound anti-tumor effects were observed when DZD2269 was in combination with immune checkpoint inhibitors, radiotherapy, or chemotherapy. A good PK/PD relationship was observed in these animal models. In the phase 1 clinical study, downregulation of pCREB was detected in human T cells, consistent with preclinical prediction. Our data support further clinical development of DZD2269 in patients with cancer. METHODS: The selectivity of DZD2269 for adenosine receptors was tested in engineered cell lines, and its efficacy in blocking A2aR signaling and reversing adenosine-mediated immunosuppression was assessed in human T cells and peripheral blood mononuclear cells (PBMCs). The anti-tumor effects of DZD2269 were evaluated in multiple syngeneic mouse models as a single agent as well as in combination with chemotherapy, radiotherapy, or immune checkpoint inhibitors. A phase 1 study in healthy volunteers (NCT04932005) has been initiated to assess safety, pharmacokinetics (PK) and pharmacodynamics (PD) of DZD2269. RESULTS: Adenosine stimulates phosphorylation of cyclic AMP response element binding protein (CREB) in T cells and inhibits anti-tumor cytokine secretion in PBMCs in a dose-dependent manner. DZD2269 was able to reverse the immunosuppression induced by high concentrations of adenosine, as demonstrated by inhibiting CREB phosphorylation in T cells, restoring Th1 cytokine secretion in PBMCs, and stimulating dendritic cells (DCs) maturation. As a single agent, DZD2269 showed anti-tumor growth in multiple syngeneic mouse tumor models, and more profound anti-tumor effects were observed when DZD2269 was in combination with immune checkpoint inhibitors, radiotherapy, or chemotherapy. A good PK/PD relationship was observed in these animal models. In the phase 1 clinical study, downregulation of pCREB was detected in human T cells, consistent with preclinical prediction. CONCLUSION: DZD2269 is a novel A2aR antagonist which can fully block A2aR mediated immunosuppression commonly found in TME. Clinical development of DZD2269 in patients with cancer is warranted (NCT04634344).

[Effect of electroacupuncture on expression of Kisspeptin protein in hypothalamus of rats with polycystic ovary syndrome].

OBJECTIVE: To investigate the effect of electroacupuncture (EA) on the expression of Kisspeptin protein and activities of the hypothalamic-pituitary-ovarian axis(HPOA) in rats with Letrozole-induced polycystic ovary syndrome (PCOS). METHODS: Female SD rats were randomly divided into normal control, PCOS model and EA groups (n=6 rats in each group). The PCOS model was established by continuous gavage of letrozole for 21 d. EA(2 Hz/100 Hz, 0.6-1.4 mA) was applied to bilateral "Daimai" (GB26) for 20 min, once every day for 15 d. Body mass was measured every 4 days. Serum follicular stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), and testosterone (T) were detected by radioimmunoassay. Histopathological changes of the ovarian were observed after H.E. staining, and the expression level of Kisspeptin protein in the hypothalamus was detected by Western blot. RESULTS: Following modeling, the body mass, serum T and LH contents, hypothalamic Kisspeptin protein expression and the number of ovarian follicles were significantly increased (P<0.05, P<0.01), while the number of ovarian corpus luteum was apparently decreased in comparison with the normal group (P<0.01). After EA intervention, the serum T, LH and E2 contents, the expression of Kisspeptin protein and the number of ovarian follicles were notably down-regulated (P<0.05, P<0.01), and the number of corpus luteum was significantly increased (P<0.01) in comparison with the model group. CONCLUSION: EA can regulate the levels of sex hormones and HPOA of PCOS rats, which may be related to its effect in down-regulating the expression of Kisspeptin protein in the hypothalamus.

Osimertinib (AZD9291) increases radio­sensitivity in EGFR T790M non­small cell lung cancer.

Osimertinib (AZD9291) is a third generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that has demonstrated significant clinical benefits in patients with EGFR­sensitizing mutations or the T790M mutation. However, the potential therapeutic effect of osimertinib combined with ionizing irradiation (IR) is not well understood. The present study investigated treatment with osimertinib combined with IR in EGFR T790M non­small cell lung cancer (NCI­H1975) in vitro and in vivo. The results revealed that osimertinib inhibited proliferation and clonogenic survival following irradiation, decreased G2/M phase arrest in irradiated cells, and delayed DNA damage repair in a concentration­ and time­dependent manner. Furthermore, osimertinib alone or in combination with IR, blocked the phosphorylation of EGFR (Tyr1068/Tyr1173), protein kinase B and extracellular signal­regulated kinase. Osimertinib also enhanced the antitumor activity of IR in tumor­bearing nude mice. The results of the present study indicated that osimertinib has therapeutic potential as a radiation­sensitizer in lung cancer cells harboring the EGFR T790M mutation, providing a rationale for clinically combining osimertinib with irradiation in EGFR T790M non­small cell lung cancer.

Prospective study revealed prognostic significance of responses in leptomeningeal metastasis and clinical value of cerebrospinal fluid-based liquid biopsy.

OBJECTIVE: Leptomeningeal metastasis (LM) secondary to non-small cell lung cancer (NSCLC) is a devastating complication associated with poor prognosis. Diagnosis and assessment of responses in LM have been challenging due to limitation of traditional imaging tools and lack of standard evaluation criteria until very recently. To bridge this gap, we conducted the first prospective, observational study in cytologically diagnosed NSCLC-LM patients (NCT02803619). PATIENTS AND METHODS: A total of 49 NSCLC-LM patients were enrolled. LM responses were evaluated with a composite endpoint integrating neurological symptoms, cerebrospinal fluid (CSF) parameters and central nervous system (CNS) imaging. Primary outcome was overall survival (OS) after diagnosis of LM. Exploratory endpoint was the association between OS and prognostic factors. Primary tumor and CSF samples were collected for biomarker analysis. RESULTS: 93.9% of the cohort carried oncogenic drivers, and 85.7% harbored EGFR activating mutations. Median OS since LM diagnosis of the overall population was 9.7 months. EGFR mutant LM patients had a longer survival compared with wildtype ones. LM clinical responses assessed by the composite endpoint showed significant correlation with OS. Status of EGFR activating mutations was highly concordant between primary tumor and CSF. T790 M occurrence in CNS lesions was relatively rare and associated with intracranial exposure level of EGFR-TKIs. CONCLUSION: Our results supported the composite endpoint for objective response evaluation of LM was valid, suggested LM outweighed peripheral lesions on the impact to patient survival, and emphasized the urge and promise of development of CNS-penetrant targeted therapies to improve clinical outcome of NSCLC-LM patients.

Heterogeneous responses and resistant mechanisms to crizotinib in ALK-positive advanced non-small cell lung cancer.

BACKGROUND: ALK-tyrosine kinase inhibitors (TKIs) have been proven effective for treating ALK-positive non-small cell lung cancer (NSCLC), although patients present with variable responses and disease progression courses. The detailed underlying molecular mechanisms require further investigation to yield a better prognosis. METHODS: Targeted next-generation sequencing (NGS) mutation profiling was performed on samples from 42 NSCLC patients confirmed positive for ALK rearrangements by fluorescence in situ hybridization or immunohistochemistry who experienced disease progression after crizotinib treatment. RESULTS: ALK rearrangements were not confirmed in six patients (14%) with other potential oncogenic drivers identified by NGS, who therefore did not respond to crizotinib and had significantly shorter overall survival (OS) compared to NGS ALK -positive patients. Fifteen ALK activating mutations were detected in 8 out of 26 post-treatment samples (31%), among which ALK L1196M and G1269A were the most common acquired mutations detected in half of the patients with ALK activating mutations. Dynamic monitoring of the genetic evolution in one patient revealed both spatial and temporal heterogeneity of resistant mechanisms during different ALK-TKI treatment courses. Activation of ALK downstream or bypass pathways was detected in patients without ALK activating mutations, such as genetic alterations in PIK3CA, MET, and KRAS. Interestingly, we identified two patients with acquired mutations in the DNA mismatch repair gene POLE, which resulted in a dramatically increased tumor mutation burden, and might contribute to the poor response to crizotinib. CONCLUSIONS: Heterogeneous resistant mechanisms have been identified and correlate to diverse responses to crizotinib. Comprehensive and dynamic mutation profiling is required to better predict clinical outcomes.

The brain-penetrant clinical ATM inhibitor AZD1390 radiosensitizes and improves survival of preclinical brain tumor models.

Poor survival rates of patients with tumors arising from or disseminating into the brain are attributed to an inability to excise all tumor tissue (if operable), a lack of blood-brain barrier (BBB) penetration of chemotherapies/targeted agents, and an intrinsic tumor radio-/chemo-resistance. Ataxia-telangiectasia mutated (ATM) protein orchestrates the cellular DNA damage response (DDR) to cytotoxic DNA double-strand breaks induced by ionizing radiation (IR). ATM genetic ablation or pharmacological inhibition results in tumor cell hypersensitivity to IR. We report the primary pharmacology of the clinical-grade, exquisitely potent (cell IC50, 0.78 nM), highly selective [>10,000-fold over kinases within the same phosphatidylinositol 3-kinase-related kinase (PIKK) family], orally bioavailable ATM inhibitor AZD1390 specifically optimized for BBB penetration confirmed in cynomolgus monkey brain positron emission tomography (PET) imaging of microdosed 11C-labeled AZD1390 (Kp,uu, 0.33). AZD1390 blocks ATM-dependent DDR pathway activity and combines with radiation to induce G2 cell cycle phase accumulation, micronuclei, and apoptosis. AZD1390 radiosensitizes glioma and lung cancer cell lines, with p53 mutant glioma cells generally being more radiosensitized than wild type. In in vivo syngeneic and patient-derived glioma as well as orthotopic lung-brain metastatic models, AZD1390 dosed in combination with daily fractions of IR (whole-brain or stereotactic radiotherapy) significantly induced tumor regressions and increased animal survival compared to IR treatment alone. We established a pharmacokinetic-pharmacodynamic-efficacy relationship by correlating free brain concentrations, tumor phospho-ATM/phospho-Rad50 inhibition, apoptotic biomarker (cleaved caspase-3) induction, tumor regression, and survival. On the basis of the data presented here, AZD1390 is now in early clinical development for use as a radiosensitizer in central nervous system malignancies.

EGFR L792H and G796R: Two Novel Mutations Mediating Resistance to the Third-Generation EGFR Tyrosine Kinase Inhibitor Osimertinib.

BACKGROUND: The third-generation EGFR tyrosine kinase inhibitor osimertinib has been approved in many countries to treat advanced NSCLC in patients with the EGFR T790M mutation. As the development of acquired resistance is inevitable, it is urgent that the mechanisms of such resistance be clarified. METHODS: DNA samples from a cohort of 340 patients with lung adenocarcinoma who were taking osimertinib were subjected to next-generation sequencing and screened in terms of the frequencies of the L792H and G796R mutations. Ba/F3 cells stably expressing the EGFR L858R/T790M mutations (in cis) with either the L792H or G796R mutation were created to investigate the impact of the two novel mutations on EGFR tyrosine kinase inhibitors and other potential drug combinations in vitro. Structural analyses were performed by using Schrödinger/Maestro software (version 11.1.012, Schrödinger LLC, Cambridge, MA). RESULTS: L792H and G796R were detected in 1.76% (six of 340) and 0.56% (two of 340) patients with lung adenocarcinoma treated with osimertinib, respectively. The introduction of L792H or G796R mutations against an L858R/T790M background caused dramatic reductions in osimertinib sensitivity. Structural modeling showed that mutations in cis with T790M either forced the ligand (osimertinib) to rotate out (breaking the binding) or pulled the hinge loop (breaking the hinge). Various other drug combinations. including cetuximab with EAI045, failed to inhibit either cis mutant effectively. CONCLUSIONS: The EGFR L858R/T790M/L792H and L858R/T790M/G796R mutations conferred resistance to osimertinib both in vitro and in silico. For patients in whom the two resistance mutations occur at low frequency, more precise treatment strategies and additional combinational approaches are required.

Enhanced efficacy of AZD3759 and radiation on brain metastasis from EGFR mutant non-small cell lung cancer.

The prognosis of patients with brain metastasis (BM) is poor. In our study, we demonstrated that AZD3759, an EGFR tyrosine kinase inhibitors (TKIs) with excellent blood-brain barrier (BBB) penetration, combined with radiation enhanced the antitumor efficacy in BM model from EGFR mutant (EGFRm) NSCLC. Besides, the antitumor activity displayed no difference between radiation concurrently with AZD3759 and radiation sequentially with AZD3759. Mechanistically, we found that two factors determined the enhanced efficacy: cells with EGFRm which were sensitive to AZD3759, and a relative high concentration of AZD3759. We have validated mechanisms underlying the radiosensitizing effect of AZD3759, which were involved in decreased cell proliferation and survival, and suppressed repair of DNA damage. Moreover, our study found that AZD3759 inhibited both the non-homologous end joining (NHEJ) and homologous recombination (HR) DNA double-strand breaks (DSBs) repair pathway, and abrogated the G2/M checkpoint to suppress DNA damage repair. We also detected the BBB penetration of AZD3759 when combined with cranial radiation. The results showed the BBB penetration of AZD3759 was decreased within 24 hr after radiation, however, the free concentration of AZD3759 in brain kept at a high level in the context of radiation. In conclusion, our findings suggest that AZD3759 combined with radiation enhances the antitumor activity in BM from EGFRm NSCLC, this combination therapy may be an effective treatment option for BM from EGFRm NSCLC.

Activity and safety of AZD3759 in EGFR-mutant non-small-cell lung cancer with CNS metastases (BLOOM): a phase 1, open-label, dose-escalation and dose-expansion study.

BACKGROUND: CNS metastases-including brain and leptomeningeal metastases-from epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) are associated with poor prognosis. AZD3759 is a novel EGFR tyrosine kinase inhibitor with high capability to penetrate the blood-brain barrier. We aimed to assess the safety, tolerability, pharmacokinetics, and efficacy of AZD3759 in patients with EGFR-mutant NSCLC with brain and leptomeningeal metastases. METHODS: This open-label, multicentre, phase 1 study was undertaken at 11 centres and hospitals in Australia, South Korea, Taiwan, and the USA. Eligible patients included those with histologically confirmed, advanced-stage, EGFR-mutant NSCLC. The study was done in two parts, with dose-escalation and dose-expansion phases. In the dose-escalation phase, patients who had progressed after treatment with an EGFR tyrosine kinase inhibitor received AZD3759 at 50 mg, 100 mg, 200 mg, 300 mg, or 500 mg twice a day. In the dose-expansion phase, AZD3759 at 200 mg or 300 mg twice a day was administered to patients with either brain or leptomeningeal metastases who had never received an EGFR tyrosine kinase inhibitor and patients with leptomeningeal metastases who had been pretreated with an EGFR tyrosine kinase inhibitor. The primary objective was safety and tolerability, with severity of adverse events assessed with the National Cancer Institute's Common Terminology Criteria for Adverse Events, version 4.03. This trial is registered with ClinicalTrials.gov, number NCT02228369. FINDINGS: Between Nov 18, 2014, and Sept 7, 2016, 67 patients with NSCLC were enrolled into the study, 29 to the dose-escalation phase and 38 to the dose-expansion phase. At data cutoff (Dec 12, 2016), three (10%) patients in the dose-escalation phase and 20 (53%) in the dose-expansion phase were still receiving treatment. Dose-limiting toxic effects occurred in two (67%) of three patients who received 500 mg twice a day in the dose-escalation phase (grade 3 acne [n=1] and intolerable grade 2 mucosal inflammation [n=1]); hence, doses of 200 mg and 300 mg twice a day were selected for further assessment in the dose-expansion phase. Drug-related skin and gastrointestinal disorders of any grade occurred in 35 (92%) and 29 (76%) patients in the dose-expansion phase, respectively, and led to treatment discontinuation in one (4%) patient treated with 200 mg twice a day (grade 3 increase of alanine aminotransferase and aspartate aminotransferase) and two (13%) patients given 300 mg twice a day (grade 3 diarrhoea [n=1] and grade 3 skin rash [n=1]). Grade 3 skin and gastrointestinal disorders occurred in four (17%) and two (9%) patients, respectively, at a dose of 200 mg twice a day, and in six (40%) and four (27%) patients, respectively, at a dose of 300 mg twice a day. No grade 4 disorders arose. Other grade 3 disorders included hepatobiliary and renal disorders (three [13%] at 200 mg twice a day), asthenia (one [7%] at 300 mg twice a day), infections and infestations (one [7%] at 300 mg twice a day), and metabolism and nutrition disorders (one [4%] at 200 mg twice a day and one [7%] at 300 mg twice a day). INTERPRETATION: AZD3759 at a dose of 200 mg twice daily showed a tolerable safety profile in patients with NSCLC and CNS metastases who had either never received a tyrosine kinase inhibitor or who had been pretreated with a tyrosine kinase inhibitor. The good penetration of the blood-brain barrier by AZD3759, and its promising clinical activity, support further assessment of this compound in studies. FUNDING: AstraZeneca.

EGFR G796D mutation mediates resistance to osimertinib.

Osimertinib is an effective third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) approved in multiple countries and regions for patients with EGFR T790M mutation-positive non-small cell lung cancer (NSCLC). Despite impressive initial tumor responses, development of drug resistance ultimately limits the benefit of this compound. Mechanisms of resistance to osimertinib are just beginning to emerge, such as EGFR C797S and L718Q mutations, BRAF V600E and PIK3CA E545K mutations, as well as ERBB2 and MET amplification. However, a comprehensive view is still missing. In this study, we presented the first case of Chinese NSCLC patient who developed resistance to osimertinib, and discovered de novo EGFR G796D mutation as a potential mechanism. Our findings provided insights into mechanisms of resistance to osimertinib and highlighted tumor heterogeneity and clonal evolution during the development of drug resistance.

Acquired MET Y1248H and D1246N Mutations Mediate Resistance to MET Inhibitors in Non-Small Cell Lung Cancer.

Purpose:MET amplification, responsible for 20% of acquired resistance to EGFR tyrosine kinase inhibitor (TKI) in patients with advanced non-small cell lung cancer (NSCLC), presents an attractive target. Numerous studies have conferred susceptibility of MET mutations and focal amplification to targeted MET-TKIs. However, the mechanism underlying MET-TKIs-induced resistance remains elusive.Experimental Design: We conducted a cohort of 12 patients with advanced NSCLC who developed resistance to a combinatorial therapy consisting of gefitinib and a type I MET-TKI. We performed capture-based targeted ultra-deep sequencing on serial tumor biopsies and plasmas ctDNA samples to detect and quantify genetic alterations.Results: We identified 2 newly acquired MET mutations, Y1248H and D1246N, in 2 patients and further confirmed their resistance against type I MET-TKIs in silco, in vitro, and in vivo Interestingly, NIH3T3 cells harboring either mutation exhibited responses to type II MET-TKIs, suggesting sequential use of MET-TKIs may offer a more durable response. In addition, we also discovered that EGFR amplification may act as an alternative MET-TKI resistance mechanism.Conclusions: Our study provides insight into the diversity of mechanisms underlying MET-TKI-induced resistance and highlights the potential of sequential use of MET-TKIs. Clin Cancer Res; 23(16); 4929-37. ©2017 AACR.

AZD3759, a BBB-penetrating EGFR inhibitor for the treatment of EGFR mutant NSCLC with CNS metastases.

Non-small-cell lung cancer patients with activating mutations in epidermal growth factor receptor (EGFR) respond to EGFR tyrosine kinase inhibitor (TKI) treatment. Nevertheless, patients often develop central nervous system (CNS) metastases during treatment, even when their extracranial tumors are still under control. In the absence of effective options, much higher doses of EGFR TKIs have been attempted clinically, with the goal of achieving high enough drug concentrations within the CNS. Although limited tumor responses have been observed with this approach, the toxicities outside the CNS have been too high to tolerate. We report the discovery and early clinical development of AZD3759, a selective EGFR inhibitor that can fully penetrate the blood-brain barrier (BBB), with equal free concentrations in the blood, cerebrospinal fluid, and brain tissue. Treatment with AZD3759 causes tumor regression in subcutaneous xenograft, leptomeningeal metastasis (LM), and brain metastasis (BM) lung cancer models and prevents the development of BM in nude mice. An early clinical study in patients with BM and LM treated with AZD3759 confirms its BBB-penetrant properties and antitumor activities. Our data demonstrate the potential of AZD3759 for the treatment of BM and LM and support its further clinical evaluation in larger trials.

EGFR mutation status of paired cerebrospinal fluid and plasma samples in EGFR mutant non-small cell lung cancer with leptomeningeal metastases.

PURPOSE: Central nervous system (CNS) is the prevalent site for metastases in epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI)-relapsed NSCLC patients. To understand the EGFR mutation status in paired cerebrospinal fluid (CSF) and plasma samples after EGFR-TKI treatment failure might be useful to guide the treatment of intra- and extracranial tumors in those patients. METHODS: Paired CSF and plasma samples were collected from seven NSCLC patients with CNS metastases after EGFR-TKI failure. EGFR mutations were tested by amplification refractory mutation system (ARMS) and droplet digital PCR (ddPCR) methods. Gefitinib concentrations were evaluated by high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS). RESULTS: EGFR mutations were detected in all seven CSF samples, including three of E19-Del, three of L858R and one of E19-Del&T790M by both methods. On the other hand, majority of the matched plasma samples (5/7) were negative for EGFR mutations by both methods. The other two plasma samples were positive for E19-Del&T790M by ddPCR, and one of them had undetectable T790M by ARMS. Gefitinib concentration in CSF was much lower than that in plasma (mean CSF/plasma ratio: 1.8 %). CONCLUSIONS: After EGFR-TKI failure, majority of the NSCLC patients with CNS metastases remained positive detection of EGFR sensitive mutations in CSF, but much less detection in the matched plasma. Significantly low exposure of gefitinib in CSF might explain the intracranial protection of the EGFR sensitive mutation positive tumor cells.

Preclinical Comparison of Osimertinib with Other EGFR-TKIs in EGFR-Mutant NSCLC Brain Metastases Models, and Early Evidence of Clinical Brain Metastases Activity.

PURPOSE: 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. EXPERIMENTAL DESIGN: 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). RESULTS: 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, [11C]osimertinib showed markedly greater exposure in the cynomolgus monkey brain than [11C]rociletinib and [11C]gefitinib. Early clinical evidence of osimertinib activity in previously treated patients with EGFRm-advanced NSCLC and brain metastases is also reported. CONCLUSIONS: 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.

Brain-derived neurotrophic factor promotes tumorigenesis via induction of neovascularization: implication in hepatocellular carcinoma.

PURPOSE: Brain-derived neurotrophic factor (BDNF) has emerged as a novel angiogenic factor, and yet its impact on tumorigenesis is unclear. This study aimed at investigating the roles of BDNF in angiogenesis and tumor development. EXPERIMENTAL DESIGN: BDNF was overexpressed in a mouse endothelial cell (EC) line by stable transfection, and angiogenic properties of the transfectants were assessed. Microarray analysis was employed to explore the molecular pathways. The impact of modulating BDNF levels in two mouse EC lines on tumorigenic potential of a transformed mouse liver cell line was evaluated by an in vivo cotransplantation model. BDNF and tropomyosin receptor kinase B (TrkB) protein levels were determined in 50 pairs of human hepatocellular carcinoma (HCC) tissues by Western blotting and immunohistochemistry. Survival analysis was carried out to determine their clinical significance. RESULTS: Overexpression of BDNF could promote EC proliferation, migration, invasion, and survival. Microarray and molecular studies showed that RhoA, caspase-9, caspase-3, growth arrest specific 6, and VEGF could mediate BDNF/TrkB-induced angiogenesis. The cotransplantation experiment showed that high BDNF-expressing ECs could facilitate tumor angiogenesis and growth, whereas knockdown of BDNF by short hairpin RNAs impaired such effects. Furthermore, examination on human HCC tissues revealed upregulation of BDNF and TrkB protein levels in 46.0% and 33.3% of the cases studied, respectively. Immunohistochemistry disclosed strong BDNF reactivity in both tumor and endothelial cells. High TrkB expression was associated with shorter overall survival. CONCLUSIONS: BDNF/TrkB system was crucial for tumor angiogenesis and growth, which may represent a potential target for antiangiogenic therapy in HCC.