Futibatinib for FGFR2-Rearranged Intrahepatic Cholangiocarcinoma.

BACKGROUND: Alterations in fibroblast growth factor receptor 2 (FGFR2) have emerged as promising drug targets for intrahepatic cholangiocarcinoma, a rare cancer with a poor prognosis. Futibatinib, a next-generation, covalently binding FGFR1-4 inhibitor, has been shown to have both antitumor activity in patients with FGFR-altered tumors and strong preclinical activity against acquired resistance mutations associated with ATP-competitive FGFR inhibitors. METHODS: In this multinational, open-label, single-group, phase 2 study, we enrolled patients with unresectable or metastatic FGFR2 fusion-positive or FGFR2 rearrangement-positive intrahepatic cholangiocarcinoma and disease progression after one or more previous lines of systemic therapy (excluding FGFR inhibitors). The patients received oral futibatinib at a dose of 20 mg once daily in a continuous regimen. The primary end point was objective response (partial or complete response), as assessed by independent central review. Secondary end points included the response duration, progression-free and overall survival, safety, and patient-reported outcomes. RESULTS: Between April 16, 2018, and November 29, 2019, a total of 103 patients were enrolled and received futibatinib. A total of 43 of 103 patients (42%; 95% confidence interval, 32 to 52) had a response, and the median duration of response was 9.7 months. Responses were consistent across patient subgroups, including patients with heavily pretreated disease, older adults, and patients who had co-occurring TP53 mutations. At a median follow-up of 17.1 months, the median progression-free survival was 9.0 months and overall survival was 21.7 months. Common treatment-related grade 3 adverse events were hyperphosphatemia (in 30% of the patients), an increased aspartate aminotransferase level (in 7%), stomatitis (in 6%), and fatigue (in 6%). Treatment-related adverse events led to permanent discontinuation of futibatinib in 2% of the patients. No treatment-related deaths occurred. Quality of life was maintained throughout treatment. CONCLUSIONS: In previously treated patients with FGFR2 fusion or rearrangement-positive intrahepatic cholangiocarcinoma, the use of futibatinib, a covalent FGFR inhibitor, led to measurable clinical benefit. (Funded by Taiho Oncology and Taiho Pharmaceutical; FOENIX-CCA2 ClinicalTrials.gov number, NCT02052778.).

Convergent MAPK pathway alterations mediate acquired resistance to FGFR inhibitors in FGFR2 fusion-positive cholangiocarcinoma.

BACKGROUND & AIMS: There is a knowledge gap in understanding mechanisms of resistance to fibroblast growth factor receptor (FGFR) inhibitors (FGFRi) and a need for novel therapeutic strategies to overcome it. We investigated mechanisms of acquired resistance to FGFRi in patients with FGFR2-fusion-positive cholangiocarcinoma (CCA). METHODS: A retrospective analysis of patients who received FGFRi therapy and underwent tumor and/or cell-free DNA analysis, before and after treatment, was performed. Longitudinal circulating tumor DNA samples from a cohort of patients in the phase I trial of futibatinib (NCT02052778) were assessed. FGFR2-BICC1 fusion cell lines were developed and secondary acquired resistance mutations in the mitogen-activated protein kinase (MAPK) pathway were introduced to assess their effect on sensitivity to FGFRi in vitro. RESULTS: On retrospective analysis of 17 patients with repeat sequencing following FGFRi treatment, new FGFR2 mutations were detected in 11 (64.7%) and new alterations in MAPK pathway genes in nine (52.9%) patients, with seven (41.2%) patients developing new alterations in both the FGFR2 and MAPK pathways. In serially collected plasma samples, a patient treated with an irreversible FGFRi tested positive for previously undetected BRAF V600E, NRAS Q61K, NRAS G12C, NRAS G13D and KRAS G12K mutations upon progression. Introduction of a FGFR2-BICC1 fusion into biliary tract cells in vitro sensitized the cells to FGFRi, while concomitant KRAS G12D or BRAF V600E conferred resistance. MEK inhibition was synergistic with FGFRi in vitro. In an in vivo animal model, the combination had antitumor activity in FGFR2 fusions but was not able to overcome KRAS-mediated FGFRi resistance. CONCLUSIONS: These findings suggest convergent genomic evolution in the MAPK pathway may be a potential mechanism of acquired resistance to FGFRi. CLINICAL TRIAL NUMBER: NCT02052778. IMPACT AND IMPLICATIONS: We evaluated tumors and plasma from patients who previously received inhibitors of fibroblast growth factor receptor (FGFR), an important receptor that plays a role in cancer cell growth, especially in tumors with abnormalities in this gene, such as FGFR fusions, where the FGFR gene is fused to another gene, leading to activation of cancer cell growth. We found that patients treated with FGFR inhibitors may develop mutations in other genes such as KRAS, and this can confer resistance to FGFR inhibitors. These findings have several implications for patients with FGFR2 fusion-positive tumors and provide mechanistic insight into emerging MAPK pathway alterations which may serve as a therapeutic vulnerability in the setting of acquired resistance to FGFRi.

Plain language summary of the FOENIX-CCA2 study: futibatinib for people with advanced bile duct cancer.

WHAT IS THIS SUMMARY ABOUT?: This summary describes the results from a phase 2 study called FOENIXCCA2. The study evaluated treatment with futibatinib in people with a rare form of advanced bile duct cancer called intrahepatic cholangiocarcinoma (or iCCA), where the tumors have changes in the structure of a gene called FGFR2. These changes include FGFR2 gene fusions. Bile duct cancer often returns after surgery or cannot be treated by surgery because the tumor has spread, so it requires treatment with chemotherapy. People live for a median of 1 year after their first chemotherapy treatment and 6 months after their second treatment. This study included people whose cancer had grown/spread after one or more chemotherapy treatments. The aims of the study were to see if futibatinib could shrink the size of tumors and stop the cancer from growing/spreading and to see how long people lived when treated with futibatinib. Clinicians also looked at side effects from taking futibatinib and at how it affected people's quality of life. WHAT WERE THE RESULTS?: Futibatinib treatment shrank tumors in over 80% of people who received treatment. Tumors shrank by at least 30% in 42% of people. Futibatinib stopped tumors from growing/spreading for a median of 9.7 months. People who took the medicine lived for a median of 21.7 months, and 72% of people were still alive after 1 year. Side effects from taking futibatinib were like those reported for similar medicines, and clinicians considered the side effects to be manageable by adjusting the dose of futibatinib or treating the side effects. Most people reported that their quality of life stayed the same or improved during the first 9 months of taking futibatinib. WHAT DO THE RESULTS MEAN?: The results support the use of futibatinib for treating people with advanced bile duct cancer. Based on the results of this study, futibatinib is now approved in the US, Europe, and Japan. Futibatinib is approved for treating adults with advanced bile duct cancer who have received previous treatment for their cancer, and whose tumors have a gene fusion or other change in the FGFR2 gene.Clinical Trial Registration: NCT02052778 (FOENIX-CCA2).

Phase 1 cohort expansion study of LY3023414, a dual PI3K/mTOR inhibitor, in patients with advanced mesothelioma.

BACKGROUND LY3023414 is a selective, ATP competitive inhibitor of class I PI3K isoforms, mTORC1/2 and DNA-PK. A Phase 1 dose escalation, 200 mg twice daily (BID) of LY3023414 was the determined recommended phase 2 dose (RP2D). We report the antitumor activity and safety of LY3023414 monotherapy in patients with advanced mesothelioma.METHODS Patients enrolled had advanced malignant pleural or peritoneal mesothelioma with measurable disease, ECOG PS 0-1, were refractory or ineligible to receive standard therapies. Patients received LY3023414 200 mg BID. This dose expansion cohort is intended to evaluate preliminary antitumor activity of LY3023414 by overall response rate. Safety, tolerability and pharmacokinetics were assessed. Biomarkers associated with treatment response was an exploratory endpoint. RESULTS Forty-two patients received LY3023414 for a median duration of 11.2 weeks (range: 1.1-53.0). One patient had a confirmed partial response (PR) (ORR 2.4%). Three patients had an unconfirmed PR. Seventeen patients had stable disease (SD) (DCR 43%). Most common adverse events (AEs) included fatigue (43%), nausea (43%), decreased appetite (38%), vomiting (33%), and diarrhea (29%). AEs were mostly mild or moderate. Grade ≥ 3 AEs were reported for 21% of patients with fatigue as the most frequent event (10%). Alterations of BAP1 were identified in 11/19 patients as the most common molecular aberration, followed by SETD2 and NF2 alterations. No obvious pattern of genetic changes/mutations in single genes or pathways was associated with anti-tumor activity. CONCLUSION LY3023414 monotherapy (200 mg BID) demonstrated an acceptable and manageable safety profile with limited single-agent activity in patients with advanced mesothelioma. ClinicalTrials.gov identifier: NCT01655225; Date of registration: 19 July 2012.

Phase 1 dose-escalation study of a novel oral PI3K/mTOR dual inhibitor, LY3023414, in patients with cancer.

LY3023414 is an oral, selective adenosine triphosphate-competitive inhibitor of class I phosphatidylinositol 3-kinase isoforms, mammalian target of rapamycin, and DNA-protein kinase in clinical development. We report results of a 3 + 3 dose-escalation Phase 1 study for twice-daily (BID) dosing of LY3023414 monotherapy in Japanese patients with advanced malignancies. The primary objective was to evaluate tolerability and safety of LY3023414. Secondary objectives were to evaluate pharmacokinetics and to explore antitumor activity. A total of 12 patients were enrolled and received 150 mg (n = 3) or 200 mg (n = 9) LY3023414 BID. Dose-limiting toxicities were only reported at 200 mg LY3023414 for 2 patients with Grade 3 stomatitis. Common treatment-related adverse events (AEs) across both the dose levels included stomatitis (75.0%), nausea (66.7%), decreased appetite (58.3%), diarrhea, and decreased platelet count (41.7%), and they were mostly mild or moderate in severity. Related AEs Grade ≥ 3 reported for ≥1 patient included anemia, stomatitis, hypophosphatemia, and hyperglycemia (n = 2, 16.7%). Two patients discontinued due to AEs (interstitial lung disease and stomatitis). No fatal events were reported. The pharmacokinetic profile of LY3023414 was characterized by rapid absorption and elimination. Five patients had a best overall response of stable disease (150 mg, n = 3; 200 mg, n = 2) for a 55.6% disease control rate. LY3023414 up to 200 mg BID is tolerable and safe in Japanese patients with advanced malignancies.

Correction to: Phase 1 dose-escalation study of a novel oral PI3K/mTOR dual inhibitor, LY3023414, in patients with cancer.

The article Phase 1 dose-escalation study of a novel oral PI3K/mTOR dual inhibitor, LY3023414, in patients with cancer, written by Shunsuke Kondo, Masaomi Tajimi, Tomohiko Funai, Koichi Inoue, Hiroya Asou, Vinay Kumar Ranka, Volker Wacheck, Toshihiko Doi, was originally published electronically on the publisher's internet portal on 23 June 2020 without open access.

MET-targeting antibody (emibetuzumab) and kinase inhibitor (merestinib) as single agent or in combination in a cancer model bearing MET exon 14 skipping.

Purpose Approximately 3% of lung cancer bears mutations leading to MET exon 14 skipping, an oncogenic driver which is further evidenced by case reports of patient response to MET kinase inhibitor treatment. Approximately 15% of tumors harboring MET exon14 skipping have concurrent MET amplification. Experimental Design Merestinib is a type II MET kinase inhibitor. Emibetuzumab, a bivalent anti-MET antibody, internalizes MET receptor. Each single agent and the combination were evaluated in the Hs746t gastric cancer line bearing MET exon14 skipping and MET amplification. Results Merestinib inhibited Hs746t cell proliferation (IC50=34 nM) and totally eliminated pMET at 100nM. Emibetuzumab showed little anti-proliferative activity against Hs746t cells (IC50>100nM), did not reduce pMET, and slightly reduced cell surface MET. In the Hs746t xenograft model, dose dependent differences in durability of response were seen with merestinib including durable tumor regression (91.8%) at 12 mg/kg qd. Emibetuzumab treatment (10mg/kg qw) provided transient tumor regression (37.7%), but tumors re-grew while on treatment. Concurrent combination of merestinib (6 mg/kg qd) and emibetuzumab resulted in 85% tumor regression, while a sequential combination (initiating merestinib first) resulted in longer duration of treatment response. Conclusions Data in this study support a clinical evaluation of merestinib in patients with MET exon 14 skipping (NCT02920996). As a type II MET kinase inhibitor, merestinib may provide a therapeutic option to treatment naïve patients or to patients who progress on type I MET inhibitor treatment. Data also support clinical evaluation of the sequential combination of merestinib with emibetuzumab when patients progress on single agent merestinib.

MET in gastric cancer with liver metastasis: The relationship between MET amplification and Met overexpression in primary stomach tumors and liver metastasis.

BACKGROUND AND OBJECTIVES: Although MET amplification/overexpression was observed in a subset of gastric cancer (GC) patients, the relationship between MET amplification/overexpression in primary GC and liver metastasis was unclear. METHODS: GC samples and matched liver metastases (N = 47) were analyzed by fluorescence/silver in-situ hybridization (FISH/SISH) and by immunohistochemistry for MET amplification and MET expression, respectively. MET-copy number (CN) and Met expression data from The Cancer Genome Atlas Stomach Adenocarcinoma (TCGA-STAD, N = 356) were also analyzed. RESULTS: Significant overlap existed between MET amplification and Met expression in both primary stomach tumors (P = 0.013) and liver metastasis (P = 0.001). In TCGA-STAD, MET-CN (≥4 copies) and MET expression were also positively correlated (r = 0.761; P = 0.017). Comparative analysis revealed a strong association between MET expression and MET amplification (85% concurrence) in primary stomach tumors and matched liver metastasis. MET status in synchronous liver metastasis (N = 36) was correlated with primary stomach tumors. However, a significant correlation between primary tumors and liver metastases was not observed in patients with metachronous liver metastasis. Survival analyses revealed that both MET amplification and MET overexpression were prognostic of poor outcomes. CONCLUSIONS: MET amplification and Met overexpression were positively correlated in GC. MET status should be re-evaluated in GC patients with liver metastasis, especially for metachronous metastasis.

A phase I dose-escalation study of LY2875358, a bivalent MET antibody, given as monotherapy or in combination with erlotinib or gefitinib in Japanese patients with advanced malignancies.

Background MET is a tyrosine kinase receptor involved in the regulation of cell proliferation and migration. Reported here are the phase I dose-escalation results for LY2875358, a monoclonal antibody against MET, in Japanese patients with advanced malignancies. Methods The study comprised a 3 + 3 dose-escalation part for LY2875358 monotherapy in patients with advanced malignancies (Part A) followed by an assessment of LY2875358 in combination with erlotinib or gefitinib in patients with non-small cell lung cancer (Part B). LY2875358 was administered once every 2 weeks. The primary objective was to evaluate the safety and tolerability of LY2875358; secondary objectives included evaluation of pharmacokinetics, pharmacodynamics, and antitumor activity. Results Eleven patients received LY2875358 monotherapy at 3 dose levels (700 mg, N = 3; 1400 mg, N = 3; 2000 mg, N = 5) and 6 patients received LY2875358 2000 mg in combination with erlotinib (N = 3) or gefitinib (N = 3). No dose-limiting toxicities or serious adverse events related to LY2875358 were observed. The most frequently reported drug-related adverse events were hypoalbuminemia (2 patients) in Part A and dermatitis acneiform (4 patients) in Part B. LY2875358 area under the curve (AUC) and maximum concentration (Cmax) increased with dose over the dose range of 700 mg to 2000 mg. A best response of stable disease was achieved by 2/11 patients in Part A and 4/6 patients in Part B (disease control rate: 35 %). Conclusions LY2875358 at doses up to 2000 mg demonstrated a favorable safety and tolerability profile as monotherapy or in combination with erlotinib or gefitinib in Japanese patients with advanced malignancies.

Safety Profile and Adverse Event Management for Futibatinib, An Irreversible FGFR1-4 Inhibitor: Pooled Safety Analysis of 469 Patients.

PURPOSE: Futibatinib, a covalently-binding inhibitor of fibroblast growth factor receptor (FGFR)1-4 gained approval for the treatment of refractory, advanced intrahepatic cholangiocarcinoma (iCCA) harboring an FGFR2 fusion/other rearrangement. An integrated analysis was performed to evaluate safety and provide guidance on the management of futibatinib-associated adverse events (AEs) in patients with unresectable/metastatic tumors, including iCCA. PATIENTS AND METHODS: Data from three global phase I or II studies of futibatinib (NCT02052778; JapicCTI-142552) were pooled. AEs were graded per NCI CTCAE v4.03, where applicable. Safety was analyzed for patients receiving any futibatinib starting dose (overall population) and in those receiving the approved starting dose of 20 mg once every day. RESULTS: In total, 469 patients with one of 33 known tumor types were analyzed, including 318 patients who received futibatinib 20 mg every day. AEs of clinical interest (AECI; any grade/grade ≥3) in the overall population included hyperphosphatemia (82%/19%), nail disorders (27%/1%), hepatic AEs (27%/11%), stomatitis (19%/3%), palmar-plantar erythrodysesthesia syndrome (PPES; 13%/3%), rash (9%/0%), retinal disorders (8%/0%), and cataract (4%/1%). Median time to onset of grade ≥3 AECIs ranged from 9 days (hyperphosphatemia) to 125 days (cataract). Grade ≥3 hyperphosphatemia, hepatic AEs, PPES, and nail disorders resolved to grade ≤2 within a median of 7, 7, 8, and 28 days, respectively. Discontinuations due to treatment-related AEs were rare (2%), and no treatment-related deaths occurred. AE management included phosphate-lowering medication and dose adjustments. CONCLUSIONS: Futibatinib showed a consistent and manageable safety profile across patients with various tumor types. AECIs were mostly reversible with appropriate clinical management.

A phase I, open-label, single-dose study to evaluate the effect of hepatic impairment on the pharmacokinetics and safety of futibatinib.

Futibatinib is a covalently binding FGFR1-4 inhibitor that received US Food and Drug Administration approval for the treatment of patients with previously treated, advanced intrahepatic cholangiocarcinoma harboring FGFR2 gene fusions/rearrangements. This phase I trial evaluated the pharmacokinetics (PKs), safety, and tolerability of futibatinib in subjects with impaired hepatic function and matched healthy volunteers. Twenty-two subjects with hepatic impairment (8 mild [Child-Pugh 5-6], 8 moderate [7-9], and 6 severe [10-15]) and 16 matched healthy control subjects received a single oral dose of futibatinib 20 mg. Futibatinib PKs were compared between subjects with mild/moderate/severe hepatic impairment and each corresponding control cohort and the overall control cohort. Relationships between futibatinib PKs and Child-Pugh scores and liver function tests were examined via scatter/regression plots. Compared with matched controls, the area under the plasma concentration-time curve from time zero to infinity increased by 21%/20%/18% and the maximum plasma concentration (Cmax ) increased by 43%/15%/10% in subjects with mild/moderate/severe hepatic impairment, respectively. Changes were not considered clinically relevant: geometric mean ratios were within 80%-125%, except for Cmax in subjects with mild hepatic impairment (143%). No obvious trends were observed among futibatinib PK parameters versus Child-Pugh scores, bilirubin, albumin, international normalized ratio, and aspartate aminotransferase (all p > 0.05). Futibatinib was well-tolerated, with only four grade 1 treatment-emergent adverse events (mild hepatic impairment = 2 and control = 2). The results demonstrate that futibatinib dose adjustments due to mild/moderate/severe hepatic impairment are not necessary in patients receiving futibatinib 20 mg daily.

Preclinical Evaluation of the FGFR-Family Inhibitor Futibatinib for Pediatric Rhabdomyosarcoma.

Rhabdomyosarcoma (RMS) is the most common pediatric soft tissue sarcoma. Despite decades of clinical trials, the overall survival rate for patients with relapsed and metastatic disease remains below 30%, underscoring the need for novel treatments. FGFR4, a receptor tyrosine kinase that is overexpressed in RMS and mutationally activated in 10% of cases, is a promising target for treatment. Here, we show that futibatinib, an irreversible pan-FGFR inhibitor, inhibits the growth of RMS cell lines in vitro by inhibiting phosphorylation of FGFR4 and its downstream targets. Moreover, we provide evidence that the combination of futibatinib with currently used chemotherapies such as irinotecan and vincristine has a synergistic effect against RMS in vitro. However, in RMS xenograft models, futibatinib monotherapy and combination treatment have limited efficacy in delaying tumor growth and prolonging survival. Moreover, limited efficacy is only observed in a PAX3-FOXO1 fusion-negative (FN) RMS cell line with mutationally activated FGFR4, whereas little or no efficacy is observed in PAX3-FOXO1 fusion-positive (FP) RMS cell lines with FGFR4 overexpression. Alternative treatment modalities such as combining futibatinib with other kinase inhibitors or targeting FGFR4 with CAR T cells or antibody-drug conjugate may be more effective than the approaches tested in this study.

A comparative small-animal PET evaluation of [11C]tariquidar, [11C]elacridar and (R)-[11C]verapamil for detection of P-glycoprotein-expressing murine breast cancer.

PURPOSE: One important mechanism for chemoresistance of tumours is overexpression of the adenosine triphosphate-binding cassette transporter P-glycoprotein (Pgp). Pgp reduces intracellular concentrations of chemotherapeutic drugs. The aim of this study was to compare the suitability of the radiolabelled Pgp inhibitors [(11)C]tariquidar and [(11)C]elacridar with the Pgp substrate radiotracer (R)-[(11)C]verapamil for discriminating tumours expressing low and high levels of Pgp using small-animal PET imaging in a murine breast cancer model. METHODS: Murine mammary carcinoma cells (EMT6) were continuously exposed to doxorubicin to generate a Pgp-overexpressing, doxorubicin-resistant cell line (EMT6AR1.0 cells). Both cell lines were subcutaneously injected into female athymic nude mice. One week after implantation, animals underwent PET scans with [(11)C]tariquidar (n = 7), [(11)C]elacridar (n = 6) and (R)-[(11)C]verapamil (n = 7), before and after administration of unlabelled tariquidar (15 mg/kg). Pgp expression in tumour grafts was evaluated by Western blotting. RESULTS: [(11)C]Tariquidar showed significantly higher retention in Pgp-overexpressing EMT6AR1.0 compared with EMT6 tumours: the mean ± SD areas under the time-activity curves in scan 1 from time 0 to 60 min (AUC(0-60)) were 38.8 ± 2.2 min and 25.0 ± 5.3 min (p = 0.016, Wilcoxon matched pairs test). [(11)C]Elacridar and (R)-[(11)C]verapamil were not able to discriminate Pgp expression in tumour models. Following administration of unlabelled tariquidar, both EMT6Ar1.0 and EMT6 tumours showed increases in uptake of [(11)C]tariquidar, [(11)C]elacridar and (R)-[(11)C]verapamil. CONCLUSION: Among the tested radiotracers, [(11)C]tariquidar performed best in discriminating tumours expressing high and low levels of Pgp. Therefore [(11)C]tariquidar merits further investigation as a PET tracer to assess Pgp expression levels in solid tumours.

A Randomized, Open-Label Phase II Study Evaluating Emibetuzumab Plus Erlotinib and Emibetuzumab Monotherapy in MET Immunohistochemistry Positive NSCLC Patients with Acquired Resistance to Erlotinib.

INTRODUCTION: The hepatocyte growth factor receptor MET represents a resistance mechanism to epidermal growth factor receptor (EGFR) inhibition in EGFR mutant (mt) non-small cell lung cancer (NSCLC). This Phase 2 study tested whether acquired resistance to erlotinib in MET protein positive NSCLC patients enriched for EGFRmt can be overcome by emibetuzumab plus erlotinib. PATIENT AND METHODS: Patients with Stage IV NSCLC with acquired resistance to erlotinib and MET diagnostic (+) (≥ 10% of cells expressing MET at ≥ 2+ IHC staining intensity at any time) were randomized (3:1) to receive emibetuzumab 750 mg every 2 weeks with or without erlotinib 150 mg once daily. The primary objective was to evaluate the overall response rate (ORR) relative to historic control, with a co-primary objective of ORR in patients with MET expression in ≥ 60% of cells ≥ 2+ (MET ≥ 60%). RESULTS: One hundred and eleven MET+ patients received emibetuzumab plus erlotinib (N = 83) or emibetuzumab monotherapy (N = 28). 89 of 111 MET+ samples were post-erlotinib. ORR was 3.0% for emibetuzumab plus erlotinib (95% CI: 0.4, 10.5) and 4.3% for emibetuzumab (95% CI: 0.1, 21.9), in patients with post-erlotinib progression biopsies available (n = 89). Similar results were observed in patients with MET ≥ 60% expression (n = 74). Disease control rate and progression-free survival were higher for emibetuzumab plus erlotinib (50%/3.3 months) than for emibetuzumab (26%/1.6 months). No unexpected safety signals emerged. Partial responses were observed in patients with and without EGFRmt or MET amplification. EGFR sensitizing mutations were identified retrospectively in 84.2% of those with available tissue (85/101). CONCLUSION: Acquired resistance to erlotinib in MET diagnostic (+) patients was not reversed by emibetuzumab plus erlotinib or emibetuzumab monotherapy, although a subset of patients obtained clinical benefit.

Phase Ib/II Study of Enzalutamide with Samotolisib (LY3023414) or Placebo in Patients with Metastatic Castration-Resistant Prostate Cancer.

PURPOSE: To report efficacy and safety of samotolisib (LY3023414; PI3K/mTOR dual kinase and DNA-dependent protein kinase inhibitor) plus enzalutamide in patients with metastatic castration-resistant prostate cancer (mCRPC) following cancer progression on abiraterone. PATIENTS AND METHODS: In this double-blind, placebo-controlled phase Ib/II study (NCT02407054), following a lead-in segment for evaluating safety and pharmacokinetics of samotolisib and enzalutamide combination, patients with advanced castration-resistant prostate cancer with progression on prior abiraterone were randomized to receive enzalutamide (160 mg daily)/samotolisib (200 mg twice daily) or placebo. Primary endpoint was progression-free survival (PFS) assessed by Prostate Cancer Clinical Trials Working Group criteria (PCWG2). Secondary and exploratory endpoints included radiographic PFS (rPFS) and biomarkers, respectively. Log-rank tests assessed treatment group differences. RESULTS: Overall, 13 and 129 patients were enrolled in phase Ib and II, respectively. Dose-limiting toxicity was not reported in patients during phase Ib and mean samotolisib exposures remained in the targeted range despite a 35% decrease when administered with enzalutamide. In phase II, median PCWG2-PFS and rPFS was significantly longer in the samotolisib/enzalutamide versus placebo/enzalutamide arm (3.8 vs. 2.8 months; P = 0.003 and 10.2 vs. 5.5 months; P = 0.03), respectively. Patients without androgen receptor splice variant 7 showed a significant and clinically meaningful rPFS benefit in the samotolisib/enzalutamide versus placebo/enzalutamide arm (13.2 months vs. 5.3 months; P = 0.03). CONCLUSIONS: Samotolisib/enzalutamide has tolerable side effects and significantly improved PFS in patients with mCRPC with cancer progression on abiraterone, and this may be enriched in patients with PTEN intact and no androgen receptor splice variant 7.

Sphingosine kinase 1 is a relevant molecular target in gastric cancer.

Sphingosine kinase 1 (Sphk1), a lipid kinase implicated in cell transformation and tumor growth, is overexpressed in gastric cancer and is linked with a poor prognosis. The biological relevance of Sphk1 expression in gastric cancer is unclear. Here, we studied the functional significance of Sphk1 as a novel molecular target for gastric cancer by using an antisense oligonucleotide approach in vitro and in vivo. Gastric cancer cell lines (MKN28 and N87) were treated with Sphk1 with locked nucleic acid-antisense oligonucleotides (LNA-ASO). Sphk1 target regulation, cell growth, and apoptosis were assessed for single-agent Sphk1 LNA-ASO and for combinations with doxorubicin. Athymic nude mice xenografted with gastric cancer cells were treated with Sphk1 LNA and assessed for tumor growth and Sphk1 target regulation, in vivo. In vitro, nanomolar concentrations of Sphk1 LNA-ASO induced an approximately two-fold reduction in Sphk1 mRNA in both the cell lines. This resulted in a 1.6-fold increase in apoptosis and inhibited the growth of gastric cancer cells by more than 50% (P < 0.05). The combination of Sphk1 LNA-ASO with doxorubicin resulted in significant chemosensitization. In vivo, Sphk1 LNA-ASO displayed neither mRNA target regulation in xenografts nor antitumor activity in two independent nude mouse xenograft models. In conclusion, the potent single-agent activity and the synergistic effect of Sphk1 LNA-ASO in combination with chemotherapy in vitro highlight Sphk1 as a biologically relevant molecular target for gastric cancer. Further studies are warranted to overcome the challenge of delivering Sphk1-targeting RNA-therapeutics to solid tumors in vivo.

Does endovenous laser ablation induce endothelial damage at the saphenofemoral junction?

BACKGROUND AND OBJECTIVE: One of the possible complications of endovenous laser ablation (EVLA) is thrombus progression into the common femoral vein or popliteal vein with the potential risk of pulmonary embolism or stroke. We set out to investigate the effect of laser energy applied under standardized treatment conditions on biomarkers of platelet and endothelial activation and on the hemostatic system. METHODS: Twenty patients with incompetence of the great saphenous vein were included in this prospective study. Blood samples of the iliofemoral and anticubital veins were collected before, during, and after EVLA. Plasma levels of soluble (s) P-selectin, soluble thrombomodulin (sTM), prothrombin fragment F1+2 (F1+2), and d-dimer were measured. (s) P-selectin and sTM were analyzed as surrogate markers of endothelial and platelet activation. F1+2 and d-dimer were monitored to quantify the degree of surgical trauma. RESULTS: Whereas there was no immediate rise of (s) P-selectin and sTM plasma concentrations in iliofemoral or anticubital blood, plasma levels of F1+2 and d-dimer increased significantly after EVLA. CONCLUSION: Pulsed mode laser ablation with an 810-nm fiber does not induce measurable platelet and endothelium activation in the iliofemoral or systemic blood. Furthermore, the immediate surgical trauma associated with EVLA appears to be modest. The authors have indicated no significant interest with commercial supporters.

A novel type of influenza vaccine: safety and immunogenicity of replication-deficient influenza virus created by deletion of the interferon antagonist NS1.

BACKGROUND. The nonstructural protein NS1 of influenza virus counteracts the interferon-mediated immune response of the host. By deleting the open reading frame of NS1, we have generated a novel type of influenza vaccine. We studied the safety and immunogenicity of an influenza strain lacking the NS1 gene (DeltaNS1-H1N1) in healthy volunteers. METHODS. Healthy seronegative adult volunteers were randomized to receive either a single intranasal dose of the DeltaNS1-H1N1 A/New Caledonia vaccine at 1 of 5 dose levels (6.4, 6.7, 7.0, 7.4, and 7.7 log(10) median tissue culture infective dose) (n = 36 recipients) or placebo (n = 12 recipients). RESULTS. Intranasal vaccination with the replication-deficient DeltaNS1-H1N1 vaccine was well tolerated. Rhinitis-like symptoms and headache were the most common adverse events identified during the 28-day observation period. Adverse events were similarly distributed between the treatment and placebo groups. Vaccine-specific local and serum antibodies were induced in a dose-dependent manner. In the highest dose group, vaccine-specific antibodies were detected in 10 of 12 volunteers. Importantly, the vaccine also induced neutralizing antibodies against heterologous drift variants. CONCLUSIONS. We show that vaccination with an influenza virus strain lacking the viral interferon antagonist NS1 induces statistically significant levels of strain-specific and cross-neutralizing antibodies despite the highly attenuated replication-deficient phenotype. Further studies are warranted to determine whether these results translate into protection from influenza virus infection. TRIAL REGISTRATION. ClinicalTrials.gov identifier: NCT00724997 .

A Randomized-Controlled Phase 2 Study of the MET Antibody Emibetuzumab in Combination with Erlotinib as First-Line Treatment for EGFR Mutation-Positive NSCLC Patients.

INTRODUCTION: The hepatocyte growth factor receptor mesenchymal-epithelial transition (MET) is reported to be a negative prognostic marker in EGFR-mutant NSCLC and involved in resistance to EGFR inhibitors. Emibetuzumab, a humanized immunoglobulin G4 monoclonal bivalent MET antibody, blocks ligand-dependent and ligand-independent hepatocyte growth factor/MET signaling. This phase 2 study compared erlotinib with and without emibetuzumab in first-line treatment of EGFR-mutant metastatic NSCLC. METHODS: Patients with stage IV EGFR-mutant NSCLC and disease control after an 8-week lead-in with erlotinib (150 mg daily) were randomized to continue taking erlotinib with or without emibetuzumab (750 mg every 2 weeks). The primary end point was progression-free survival (PFS). Additional end points included overall survival, overall response rate, safety, pharmacokinetics, and exploratory analysis of MET expression. RESULTS: No significant difference in median PFS was observed in the intent-to-treat population (9.3 months with emibetuzumab + erlotinib versus 9.5 months with erlotinib monotherapy [hazard ratio (HR) = 0.89, 90% confidence interval (CI): 0.64-1.23]). The median overall survival was 34.3 months with emibetuzumab plus erlotinib versus 25.4 months with erlotinib (HR = 0.74, 90% CI: 0.49-1.11). Emibetuzumab plus erlotinib was well tolerated, with peripheral edema and mucositis as the only adverse events occurring 10% or more frequently relative to erlotinib. Exploratory post hoc analysis showed an improvement of 15.3 months in median PFS for the 24 patients with the highest MET expression (MET expression level of 3+ in ≥90% of tumor cells) (20.7 with emibetuzumab + erlotinib versus 5.4 months with erlotinib [HR = 0.39, 90% CI: 0.17-0.91]). CONCLUSIONS: No statistically significant difference in PFS was noted in the intent-to-treat population. Exploratory analysis confirmed that high MET expression is a negative prognostic marker for patients treated with erlotinib, indicating that emibetuzumab plus erlotinib may provide clinically meaningful benefit.

Incidence and Management of Olaratumab Infusion-Related Reactions.

PURPOSE: Olaratumab is a human monoclonal immunoglobulin G1 antibody against platelet-derived growth factor receptor-α. We report the nature and frequency of infusion-related reactions (IRRs) with olaratumab in clinical trials and postmarketing reports. METHODS: Data from patients exposed to olaratumab across nine clinical trials were reviewed for IRRs. Blood samples were also analyzed for pre-existing immunoglobulin E anti-galactose-α-1,3-galactose (anti-α-Gal) antibodies. RESULTS: In the clinical trials, IRRs were identified in 70 of 485 patients (14.4%). The most frequent symptoms included flushing, fever or chills, and dyspnea. For 68 of 70 patients (97.1%), the first IRR occurred during the first two cycles of treatment. Grade 3 or worse IRRs were reported in 11 patients (2.3%), all during the first infusion and usually within 15 minutes of the start of the infusion. One IRR-related fatality (0.2%) occurred in a nonpremedicated patient with grade 3 or worse cardiac comorbidities. There was an association between grade 3 or worse IRRs and pre-existing anti-α-Gal antibodies, with a trend toward higher IRR rates in US geographies known to have a higher prevalence of anti-α-Gal antibodies. IRRs in postmarketing reports were consistent in nature and severity with those in the clinical trials. CONCLUSION: Premedication with corticosteroids and antihistamines should occur in all patients before olaratumab infusion, as indicated in labels in the United States and the European Union. Patients receiving olaratumab should be monitored for IRRs in a setting where resuscitation equipment is available for the treatment of IRRs.