Lenvatinib plus pembrolizumab for patients with previously treated, advanced, triple-negative breast cancer: Results from the triple-negative breast cancer cohort of the phase 2 LEAP-005 Study.

BACKGROUND: Novel treatments are needed for patients with advanced, triple-negative breast cancer (TNBC) that progresses or recurs after first-line treatment with chemotherapy. The authors report results from the TNBC cohort of the multicohort, open-label, single-arm, phase 2 LEAP-005 study of lenvatinib plus pembrolizumab in patients with advanced solid tumors (ClinicalTrials.gov identifier NCT03797326). METHODS: Eligible patients had metastatic or unresectable TNBC with disease progression after one or two lines of therapy. Patients received lenvatinib (20 mg daily) plus pembrolizumab (200 mg every 3 weeks; up to 35 cycles). The primary end points were the objective response rate according to Response Evaluation Criteria in Solid Tumors, version 1.1, and safety (adverse events graded by the National Cancer Institute's Common Terminology Criteria for Adverse Events, version 4.0). Duration of response, progression-free survival, and overall survival were secondary end points. RESULTS: Thirty-one patients were enrolled. The objective response rate by investigator assessment was 23% (95% confidence interval [CI], 10%-41%). Overall, the objective response rate by blinded independent central review (BICR) was 32% (95% CI, 17%-51%); and, in patients who had programmed cell death ligand 1 combined positive scores ≥10 (n = 8) and <10 (n = 22), the objective response rate was 50% (95% CI, 16%-84%) and 27% (95% CI, 11%-50%), respectively. The median duration of response by BICR was 12.1 months (range, from 3.0+ to 37.9+ months). The median progression-free survival by BICR was 5.1 months (95% CI, 1.9-11.8 months) and the median overall survival was 11.4 months (95% CI, 4.1-21.7 months). Treatment-related adverse events occurred in 94% of patients (grade 3, 52%; grade 4, 0%). One patient died due to a treatment-related adverse event of subarachnoid hemorrhage. CONCLUSIONS: The combination of lenvatinib plus pembrolizumab demonstrated antitumor activity with a manageable safety profile in patients with previously treated, advanced TNBC.

Adult brain tumour research in 2024: Status, challenges and recommendations.

In 2015, a groundswell of brain tumour patient, carer and charity activism compelled the UK Minister for Life Sciences to form a brain tumour research task and finish group. This resulted, in 2018, with the UK government pledging £20m of funding, to be paralleled with £25m from Cancer Research UK, specifically for neuro-oncology research over the subsequent 5 years. Herein, we review if and how the adult brain tumour research landscape in the United Kingdom has changed over that time and what challenges and bottlenecks remain. We have identified seven universal brain tumour research priorities and three cross-cutting themes, which span the research spectrum from bench to bedside and back again. We discuss the status, challenges and recommendations for each one, specific to the United Kingdom.

A Phase 1/2A trial of idroxioleic acid: first-in-class sphingolipid regulator and glioma cell autophagy inducer with antitumor activity in refractory glioma.

BACKGROUND: The first-in-class brain-penetrating synthetic hydroxylated lipid idroxioleic acid (2-OHOA; sodium 2-hydroxyoleate), activates sphingomyelin synthase expression and regulates membrane-lipid composition and mitochondrial energy production, inducing cancer cell autophagy. We report the findings of a multicentric first-in-human Phase 1/2A trial (NCT01792310) of 2-OHOA, identifying the maximum tolerated dose (MTD) and assessing safety and preliminary efficacy. METHODS: We performed an open-label, non-randomised trial to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics and anti-tumour activity of daily oral treatment with 2-OHOA monotherapy (BID/TID) in 54 patients with glioma and other advanced solid tumours. A dose-escalation phase using a standard 3 + 3 design was performed to determine safety and tolerability. This was followed by two expansion cohorts at the MTD to determine the recommended Phase-2 dose (RP2D). RESULTS: In total, 32 recurrent patients were enrolled in the dose-escalation phase (500-16,000 mg/daily). 2-OHOA was rapidly absorbed with dose-proportional exposure. Treatment was well-tolerated overall, with reversible grade 1-2 nausea, vomiting, and diarrhoea as the most common treatment-related adverse events (AEs). Four patients had gastrointestinal dose-limiting toxicities (DLTs) of nausea, vomiting, diarrhoea (three patients at 16,000 mg and one patient at 12,000 mg), establishing an RP2D at 12,000 mg/daily. Potential activity was seen in patients with recurrent high-grade gliomas (HGG). Of the 21 patients with HGG treated across the dose escalation and expansion, 5 (24%) had the clinical benefit (RANO CR, PR and SD >6 cycles) with one exceptional response lasting >2.5 years. CONCLUSIONS: 2-OHOA demonstrated a good safety profile and encouraging activity in this difficult-to-treat malignant brain-tumour patient population, placing it as an ideal potential candidate for the treatment of glioma and other solid tumour malignancies. CLINICAL TRIAL REGISTRATION: EudraCT registration number: 2012-001527-13; Clinicaltrials.gov registration number: NCT01792310.

Treatment with pembrolizumab in programmed death ligand 1-positive recurrent glioblastoma: Results from the multicohort phase 1 KEYNOTE-028 trial.

BACKGROUND: Current treatments for recurrent glioblastoma offer limited benefit. The authors report the antitumor activity and safety of the anti-programmed death 1 (anti-PD-1) immunotherapy, pembrolizumab, in programmed death ligand 1 (PD-L1)-positive, recurrent glioblastoma. METHODS: Adult patients with PD-L1-positive tumors were enrolled in the recurrent glioblastoma cohort of the multicohort, phase 1b KEYNOTE-028 study (ClinicalTrials.gov identifier, NCT02054806) and received pembrolizumab 10 mg/kg every 2 weeks for up to 2 years. The primary endpoint was investigator-assessed overall response rate according to the Response Evaluation Criteria in Solid Tumors, version 1.1. Archival tumor samples were assessed for PD-L1 expression levels (prospectively) and T-cell-inflamed gene expression profile score (retrospectively). RESULTS: After a median follow-up of 14 months (range, 2-55 months) among the 26 enrolled patients, the overall response rate was 8% (95% CI, 1%-26%). Two partial responses, lasting 8.3 and 22.8 months, occurred. Progression-free survival (median, 2.8 months; 95% CI, 1.9-8.1 months) rate at 6 months was 37.7%, and the overall survival (median, 13.1 months; 95% CI, 8.0-26.6 months) rate at 12 months was 58%. Correlation of therapeutic benefit to level of PD-L1 expression, gene expression profile score, or baseline steroid use could not be established. Treatment-related adverse events occurred in 19 patients (73%), and 5 patients experienced grade 3 or 4 events (there were no grade 5 events). Immune-mediated adverse events and infusion reactions occurred in 7 patients (27%). CONCLUSIONS: Pembrolizumab monotherapy demonstrated durable antitumor activity in a subset of patients with manageable toxicity in this small, signal-finding, recurrent glioblastoma cohort. Future studies evaluating rationally designed pembrolizumab combination regimens may improve outcomes in patients with recurrent glioblastoma.

A first-in-human phase 1 and pharmacological study of TAS-119, a novel selective Aurora A kinase inhibitor in patients with advanced solid tumours.

BACKGROUND: This is a first-in-human study with TAS-119, an Aurora A kinase (AurA) inhibitor. METHODS: Patients with advanced, refractory, solid tumours were enrolled into 5 dose escalation cohorts (70-300 mg BID, 4 days on/3 days off, 3 out of 4 weeks or 4 out of 4 weeks). The expansion part consisted of patients with small-cell lung cancer, HER2-negative breast cancer, MYC-amplified/ß-catenin-mutated (MT) tumours or other (basket cohort). RESULTS: In the escalation part (n = 34 patients), dose-limiting toxicities were one grade 3 nausea, two grade 2 and one grade 3 ocular toxicity and a combination of fatigue, ocular toxicity and nausea in one patient (all grade 2) at dose levels of 150, 200, 250 and 300 mg, respectively. Most frequent treatment-related adverse events were fatigue (32%), diarrhoea (24%) and ocular toxicity (24%). Toxicity grade ≥3 in ≥10% of patients were diarrhoea (15%) and increased lipase (12%). The maximum tolerated dose was 250 mg BID. Due to one additional grade 1 ocular toxicity, the RP2D was set at 200 mg BID (4 days on/3 days off, 3 out of 4 weeks), which was further explored in the expansion part (n = 40 patients). Target inhibition in paired skin biopsies was shown. CONCLUSIONS: TAS-119 has a favourable and remarkably distinct safety profile from other AurA inhibitors. CLINICAL TRIAL REGISTRATION: NCT02448589.

Quantitative Multiplex Immunofluorescence Evaluation of the Tumor Microenvironment in Pretreatment Tumors of Patients with Metastatic Breast Cancer and Serous Ovarian Carcinoma Treated with Liposomal Eribulin.

Eribulin inhibits microtubule polymerization and suppresses epithelial-mesenchymal transition. Conventional pathology approaches have not identified a precise predictive biomarker for Eribulin. We performed qmIF on pre-treatment tissue from 11 patients (6 TNBC, 5 HGSOC) treated with Eribulin-LF. T-lymphocytes were the dominant immune-subset in TME, with higher levels detected in stroma vs tumor (9% vs 2%). Greater density of CD3+ (p = 0.01) and CD3 + CD8+ (p = 0.03) cells and closer proximity between CD3 + CD8+ and tumor cells was observed in the patients with disease control (PR + SD) vs. progressive disease. QmIF identified an association between TIL infiltration and Eribulin-LF sensitivity, which should be evaluated further in prospective studies.

Intermittent schedules of the oral RAF-MEK inhibitor CH5126766/VS-6766 in patients with RAS/RAF-mutant solid tumours and multiple myeloma: a single-centre, open-label, phase 1 dose-escalation and basket dose-expansion study.

BACKGROUND: CH5126766 (also known as VS-6766, and previously named RO5126766), a novel MEK-pan-RAF inhibitor, has shown antitumour activity across various solid tumours; however, its initial development was limited by toxicity. We aimed to investigate the safety and toxicity profile of intermittent dosing schedules of CH5126766, and the antitumour activity of this drug in patients with solid tumours and multiple myeloma harbouring RAS-RAF-MEK pathway mutations. METHODS: We did a single-centre, open-label, phase 1 dose-escalation and basket dose-expansion study at the Royal Marsden National Health Service Foundation Trust (London, UK). Patients were eligible for the study if they were aged 18 years or older, had cancers that were refractory to conventional treatment or for which no conventional therapy existed, and if they had a WHO performance status score of 0 or 1. For the dose-escalation phase, eligible patients had histologically or cytologically confirmed advanced or metastatic solid tumours. For the basket dose-expansion phase, eligible patients had advanced or metastatic solid tumours or multiple myeloma harbouring RAS-RAF-MEK pathway mutations. During the dose-escalation phase, we evaluated three intermittent oral schedules (28-day cycles) in patients with solid tumours: (1) 4·0 mg or 3·2 mg CH5126766 three times per week; (2) 4·0 mg CH5126766 twice per week; and (3) toxicity-guided dose interruption schedule, in which treatment at the recommended phase 2 dose (4·0 mg CH5126766 twice per week) was de-escalated to 3 weeks on followed by 1 week off if patients had prespecified toxic effects (grade 2 or worse diarrhoea, rash, or creatinine phosphokinase elevation). In the basket dose-expansion phase, we evaluated antitumour activity at the recommended phase 2 dose, determined from the dose-escalation phase, in biomarker-selected patients. The primary endpoints were the recommended phase 2 dose at which no more than one out of six patients had a treatment-related dose-limiting toxicity, and the safety and toxicity profile of each dosing schedule. The key secondary endpoint was investigator-assessed response rate in the dose-expansion phase. Patients who received at least one dose of the study drug were evaluable for safety and patients who received one cycle of the study drug and underwent baseline disease assessment were evaluable for response. This trial is registered with ClinicalTrials.gov, NCT02407509. FINDINGS: Between June 5, 2013, and Jan 10, 2019, 58 eligible patients were enrolled to the study: 29 patients with solid tumours were included in the dose-escalation cohort and 29 patients with solid tumours or multiple myeloma were included in the basket dose-expansion cohort (12 non-small-cell lung cancer, five gynaecological malignancy, four colorectal cancer, one melanoma, and seven multiple myeloma). Median follow-up at the time of data cutoff was 2·3 months (IQR 1·6-3·5). Dose-limiting toxicities included grade 3 bilateral retinal pigment epithelial detachment in one patient who received 4·0 mg CH5126766 three times per week, and grade 3 rash (in two patients) and grade 3 creatinine phosphokinase elevation (in one patient) in those who received 3·2 mg CH5126766 three times per week. 4·0 mg CH5126766 twice per week (on Monday and Thursday or Tuesday and Friday) was established as the recommended phase 2 dose. The most common grade 3-4 treatment-related adverse events were rash (11 [19%] patients), creatinine phosphokinase elevation (six [11%]), hypoalbuminaemia (six [11%]), and fatigue (four [7%]). Five (9%) patients had serious treatment-related adverse events. There were no treatment-related deaths. Eight (14%) of 57 patients died during the trial due to disease progression. Seven (27% [95% CI 11·6-47·8]) of 26 response-evaluable patients in the basket expansion achieved objective responses. INTERPRETATION: To our knowledge, this is the first study to show that highly intermittent schedules of a RAF-MEK inhibitor has antitumour activity across various cancers with RAF-RAS-MEK pathway mutations, and that this inhibitor is tolerable. CH5126766 used as a monotherapy and in combination regimens warrants further evaluation. FUNDING: Chugai Pharmaceutical.

Association of tumour mutational burden with outcomes in patients with advanced solid tumours treated with pembrolizumab: prospective biomarker analysis of the multicohort, open-label, phase 2 KEYNOTE-158 study.

BACKGROUND: Tumour mutational burden (TMB) has been retrospectively correlated with response to immune checkpoint blockade. We prospectively explored the association of high tissue TMB (tTMB-high) with outcomes in ten tumour-type-specific cohorts from the phase 2 KEYNOTE-158 study, which assessed the anti-PD-1 monoclonal antibody pembrolizumab in patients with selected, previously treated, advanced solid tumours. METHODS: In the multi-cohort, open-label, non-randomised, phase 2 KEYNOTE-158 study, patients were enrolled from 81 academic facilities and community-based institutions across 21 countries in Africa, the Americas, Asia, and Europe. Eligible patients were aged 18 years or older, had a histologically or cytologically confirmed advanced (ie, unresectable or metastatic, or both) incurable solid tumour (eligible tumour types were anal, biliary, cervical, endometrial, mesothelioma, neuroendocrine, salivary, small-cell lung, thyroid, and vulvar), progression on or intolerance to one or more lines of standard therapy, had measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1) assessed by independent central radiological review, Eastern Cooperative Oncology Group performance status of 0 or 1, life expectancy of at least 3 months, adequate organ function, and a tumour sample for biomarker analysis. Participants were given pembrolizumab 200 mg intravenously every 3 weeks for up to 35 cycles. Tissue TMB (tTMB) was assessed in formalin-fixed paraffin-embedded tumour samples using the FoundationOne CDx assay (Foundation Medicine, Cambridge, MA, USA). The prespecified definition of tTMB-high status was at least 10 mutations per megabase. The primary endpoint was the proportion of patients with an objective response (complete or partial response) as per Response Evaluation Criteria in Solid Tumours (version 1.1) by independent central review. This prespecified analysis assessed the association between antitumour activity and tTMB in treated patients with evaluable tTMB data. Efficacy was assessed in all participants who received at least one dose of pembrolizumab, had evaluable tTMB data, and were enrolled at least 26 weeks before data cutoff (June 27, 2019), and safety was assessed in all participants who received at least one dose of pembrolizumab and had tTMB-high status. KEYNOTE-158 is registered at ClinicalTrials.gov, NCT02628067, and is ongoing. FINDINGS: Between Jan 15, 2016, and June 25, 2019, 1073 patients were enrolled. 1066 participants were treated as of data cutoff (June 27, 2019), of whom 805 (76%) were evaluable for TMB, and 105 (13%) of 805 had tTMB-high status and were assessed for safety. 1050 (98%) of 1066 patients enrolled by at least 26 weeks before data cutoff, of whom 790 (75%) were evaluable for TMB and included in efficacy analyses. 102 (13%) of these 790 patients had tTMB-high status (≥10 mutations per megabase), and 688 (87%) patients had non-tTMB-high status (<10 mutations per megabase). Median study follow-up was 37·1 months (IQR 35·0-38·3). Objective responses were observed in 30 (29%; 95% CI 21-39) of 102 patients in the tTMB-high group and 43 (6%; 5-8) of 688 in the non-tTMB-high group. 11 (10%) of 105 patients had treatment-related serious adverse events. 16 (15%) participants had a grade 3-5 treatment-related adverse event, of which colitis was the only such adverse event that occurred in more than one patient (n=2). One patient had fatal pneumonia that was assessed by the investigator to be treatment related. INTERPRETATION: tTMB-high status identifies a subgroup of patients who could have a robust tumour response to pembrolizumab monotherapy. tTMB could be a novel and useful predictive biomarker for response to pembrolizumab monotherapy in patients with previously treated recurrent or metastatic advanced solid tumours. FUNDING: Merck Sharp & Dohme Corp, a subsidiary of Merck & Co, Inc.

Phase 1/2a trial of intravenous BAL101553, a novel controller of the spindle assembly checkpoint, in advanced solid tumours.

BACKGROUND: BAL101553 (lisavanbulin), the lysine prodrug of BAL27862 (avanbulin), exhibits broad anti-proliferative activity in human cancer models refractory to clinically relevant microtubule-targeting agents. METHODS: This two-part, open-label, phase 1/2a study aimed to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of 2-h infusion of BAL101553 in adults with advanced or recurrent solid tumours. The MTD was determined using a modified accelerated titration design in phase I. Patients received BAL101553 at the MTD and at lower doses in the phase 2a expansion to characterise safety and efficacy and to determine the recommended phase 2 dose (RP2D). RESULTS: Seventy-three patients received BAL101553 at doses of 15-80 mg/m2 (phase 1, n = 24; phase 2a, n = 49). The MTD was 60 mg/m2; DLTs observed at doses ≥60 mg/m2 were reversible Grade 2-3 gait disturbance with Grade 2 peripheral sensory neuropathy. In phase 2a, asymptomatic myocardial injury was observed at doses ≥45 mg/m2. The RP2D for 2-h intravenous infusion was 30 mg/m2. The overall disease control rate was 26.3% in the efficacy population. CONCLUSIONS: The RP2D for 2-h infusion of BAL101553 was well tolerated. Dose-limiting neurological and myocardial side effects were consistent with the agent's vascular-disrupting properties. CLINICAL TRIAL REGISTRATION: EudraCT: 2010-024237-23.

Radiological evaluation of malignant pleural mesothelioma - defining distant metastatic disease.

BACKGROUND: Malignant pleural mesothelioma (MPM) is traditionally characterized by local destructive spread of the pleura and surrounding tissues. Patient outcomes in MPM with distant metastatic dissemination are lacking. METHODS: In this retrospective study, we reviewed a cohort of 164 MPM patients referred to a Phase I trials unit, aiming to describe identified metastatic sites, and correlate with clinical outcomes. RESULTS: 67% of patients were diagnosed with distant metastatic disease with a high incidence of bone (19%), visceral (14%), contralateral lung (35%) and peritoneal metastases (22%). Peritoneal metastases were more likely in epithelioid versus biphasic/ sarcomatoid MPM (p = 0.015). Overall survival was 23.8 months with no statistical difference in survival between those with distant metastases and those without. CONCLUSIONS: This report highlights the frequency of distant metastases and encourages further radiological investigations in the presence of symptoms. In particular, given the relatively high incidence of bone metastases, bone imaging should be considered in advanced MPM clinical workflow and trial protocols. The presence of distant metastases does not appear to have prognostic implications under existing treatment paradigms. This cohort of MPM patients gives an indication of patterns of metastatic spread that are likely to become prevalent as prognosis improves with emerging treatment paradigms.

Phase 1 dose-finding and pharmacokinetic study of eribulin-liposomal formulation in patients with solid tumours.

BACKGROUND: This phase 1 study examined the safety, tolerability, pharmacokinetics and preliminary efficacy of eribulin-liposomal formulation (eribulin-LF) in patients with advanced solid tumours. METHODS: Eligible patients with ECOG PS 0-1 were treated with eribulin-LF either on day 1 every 21 days (Schedule 1), or on days 1 and 15 every 28 days (Schedule 2). Doses ranged from 1.0 to 3.5 mg/m2, with dose escalation in a 3 + 3 design. The dose-expansion phase evaluated eribulin-LF in select tumour types. PRIMARY OBJECTIVES: maximum tolerated dose (MTD) and the recommended dose/schedule of eribulin-LF. RESULTS: Totally, 58 patients were enroled (median age = 62 years). The MTD was 1.4 mg/m2 (Schedule 1) or 1.5 mg/m2 (Schedule 2), the latter dose selected for the dose-expansion phase. Dose-limiting toxicity (DLTs) in Schedule 1: hypophosphatemia and increased transaminase levels. DLTs in Schedule 2: stomatitis, increased alanine aminotransferase, neutropenia and febrile neutropenia. The pharmacokinetic profile of eribulin-LF showed a similar half-life to that of eribulin (~30 h), but with a 5-fold greater maximum serum concentration and a 40-fold greater area-under-the-curve. Eribulin-LF demonstrated clinical activity with approximately 10% of patients in both schedules achieving partial responses. CONCLUSIONS: Eribulin-LF was well tolerated with a favourable pharmacokinetic profile. Preliminary evidence of clinical activity in solid tumours was observed.

Radium-223 in combination with paclitaxel in cancer patients with bone metastases: safety results from an open-label, multicenter phase Ib study.

PURPOSE: Concomitant treatment with radium-223 and paclitaxel is a potential option for cancer patients with bone metastases; however, myelosuppression risk during coadministration is unknown. This phase Ib study in cancer patients with bone metastases evaluated the safety of radium-223 and paclitaxel. METHODS: Eligible patients had solid tumor malignancies with ≥2 bone metastases and were candidates for paclitaxel. Treatment included seven paclitaxel cycles (90 mg/m2 per week intravenously per local standard of care; 3 weeks on/1 week off) plus six radium-223 cycles (55 kBq/kg intravenously; one injection every 4 weeks, starting at paclitaxel cycle 2). The primary end point was percentage of patients with grade 3/4 neutropenia or thrombocytopenia during coadministration of radium-223 and paclitaxel (cycles 2, 3) versus paclitaxel alone (cycle 1). RESULTS: Of 22 enrolled patients, 15 were treated (safety population), with 7 completing all six radium-223 cycles. Treated patients had primary cancers of breast (n = 7), prostate (n = 4), bladder (n = 1), non-small cell lung (n = 1), myxofibrosarcoma (n = 1), and neuroendocrine (n = 1). No patients discontinued treatment from toxicity of the combination. In the 13 patients who completed cycle 3, the rates of grade 3 neutropenia in cycles 2 and 3 were 31% and 8%, respectively, versus 23% in cycle 1; there were no cases of grade 4 neutropenia or grade 3/4 thrombocytopenia. Breast cancer subgroup safety results were similar to the overall safety population. CONCLUSION: Radium-223 was tolerated when combined with weekly paclitaxel, with no clinically relevant additive toxicities. This combination should be explored further in patients with bone metastases.

The Ripoptosome, a signaling platform that assembles in response to genotoxic stress and loss of IAPs.

A better understanding of the mechanisms through which anticancer drugs exert their effects is essential to improve combination therapies. While studying how genotoxic stress kills cancer cells, we discovered a large ∼2MDa cell death-inducing platform, referred to as "Ripoptosome." It contains the core components RIP1, FADD, and caspase-8, and assembles in response to genotoxic stress-induced depletion of XIAP, cIAP1 and cIAP2. Importantly, it forms independently of TNF, CD95L/FASL, TRAIL, death-receptors, and mitochondrial pathways. It also forms upon Smac-mimetic (SM) treatment without involvement of autocrine TNF. Ripoptosome assembly requires RIP1's kinase activity and can stimulate caspase-8-mediated apoptosis as well as caspase-independent necrosis. It is negatively regulated by FLIP, cIAP1, cIAP2, and XIAP. Mechanistically, IAPs target components of this complex for ubiquitylation and inactivation. Moreover, we find that etoposide-stimulated Ripoptosome formation converts proinflammatory cytokines into prodeath signals. Together, our observations shed new light on fundamental mechanisms by which chemotherapeutics may kill cancer cells.

CARD-mediated autoinhibition of cIAP1's E3 ligase activity suppresses cell proliferation and migration.

E3 ligases mediate the covalent attachment of ubiquitin to target proteins thereby enabling ubiquitin-dependent signaling. Unraveling how E3 ligases are regulated is important because miscontrolled ubiquitylation can lead to disease. Cellular inhibitor of apoptosis (cIAP) proteins are E3 ligases that modulate diverse biological processes such as cell survival, proliferation, and migration. Here, we have solved the structure of the caspase recruitment domain (CARD) of cIAP1 and identified that it is required for cIAP1 autoregulation. We demonstrate that the CARD inhibits activation of cIAP1's E3 activity by preventing RING dimerization, E2 binding, and E2 activation. Moreover, we show that the CARD is required to suppress cell proliferation and migration. Further, CARD-mediated autoregulation is also necessary to maximally suppress caspase-8-dependent apoptosis and vascular tree degeneration in vivo. Taken together, our data reveal mechanisms by which the E3 ligase activity of cIAP1 is controlled, and how its deregulation impacts on cell proliferation, migration and cell survival.

Combining DNA damaging therapeutics with immunotherapy: more haste, less speed.

The idea that chemotherapy can be used in combination with immunotherapy may seem somewhat counterproductive, as it can theoretically eliminate the immune cells needed for antitumour immunity. However, much preclinical work has now demonstrated that in addition to direct cytotoxic effects on cancer cells, a proportion of DNA damaging agents may actually promote immunogenic cell death, alter the inflammatory milieu of the tumour microenvironment and/or stimulate neoantigen production, thereby activating an antitumour immune response. Some notable combinations have now moved forward into the clinic, showing promise in phase I-III trials, whereas others have proven toxic, and challenging to deliver. In this review, we discuss the emerging data of how DNA damaging agents can enhance the immunogenic properties of malignant cells, focussing especially on immunogenic cell death, and the expansion of neoantigen repertoires. We discuss how best to strategically combine DNA damaging therapeutics with immunotherapy, and the challenges of successfully delivering these combination regimens to patients. With an overwhelming number of chemotherapy/immunotherapy combination trials in process, clear hypothesis-driven trials are needed to refine the choice of combinations, and determine the timing and sequencing of agents in order to stimulate antitumour immunological memory and improve maintained durable response rates, with minimal toxicity.

Target-based therapeutic matching of phase I trials in patients with metastatic breast cancer in a tertiary referral centre.

BACKGROUND: Greater understanding of the molecular classification of breast cancer has permitted the development of rational drug design strategies. In a phase I clinical trial setting, molecular profiling with next-generation sequencing of individual tumour samples has been employed to guide treatment. METHODS: We conducted a retrospective evaluation of clinical outcomes of patients with metastatic breast cancer (MBC) treated in phase I clinical trials at our institution to assess the benefit of molecularly matched compared to non-matched treatments. RESULTS: A total of 97 consecutive patients with MBC were enrolled onto ≥1 trial between 2009 and 2015. Fourteen patients participated in multiple trials, and a total of 113 trial encounters were reviewed in this retrospective study. Eighty-three percent of patients with molecular data available were able to participate in trials matched to molecular aberrations. Patients who were treated on matched studies had improved clinical benefit (RR: 1.80, p = 0.005), progression-free (HR: 0.52, p = 0.003) and overall survival (HR: 0.54, p < 0.001). Treatment was well tolerated with low rates of treatment discontinuation for toxicity (8% overall) that did not differ between groups. No toxicity-related deaths were observed. CONCLUSIONS: Molecular profiling for MBC patients in a phase I setting is feasible and aids therapeutic decisions with improved patient outcomes.

Detection of circulating tumour cell clusters in human glioblastoma.

Human glioblastoma (GBM) is a highly aggressive, invasive and hypervascularised malignant brain cancer. Individual circulating tumour cells (CTCs) are sporadically found in GBM patients, yet it is unclear whether multicellular CTC clusters are generated in this disease and whether they can bypass the physical hurdle of the blood-brain barrier.  Here, we assessed CTC presence and composition at multiple time points in 13 patients with progressing GBM during an open-label phase 1/2a study with the microtubule inhibitor BAL101553. We observe CTC clusters ranging from 2 to 23 cells and present at multiple sampling time points in a GBM patient with pleomorphism and extensive necrosis, throughout disease progression. Exome sequencing of GBM CTC clusters highlights variants in 58 cancer-associated genes including ATM, PMS2, POLE, APC, XPO1, TFRC, JAK2, ERBB4 and ALK. Together, our findings represent the first evidence of the presence of CTC clusters in GBM.

Safety, efficacy and survival of patients with primary malignant brain tumours (PMBT) in phase I (Ph1) trials: the 12-year Royal Marsden experience.

BACKGROUND: Primary malignant brain tumours (PMBT) constitute less than 2% of all malignancies and carry a dismal prognosis. Treatment options at relapse are limited. First-in-human solid tumour studies have historically excluded patients with PMBT due to the poor prognosis, concomitant drug interactions and concerns regarding toxicities. METHODS: Retrospective data were collected on clinical and tumour characteristics of patients referred for consideration of Ph1 trials in the Royal Marsden Hospital between June 2004 and August 2016. Survival analyses were performed using the Kaplan-Meier method, Cox proportional hazards model. Chi squared test was used to measure bivariate associations between categorical variables. RESULTS: 100pts with advanced PMBT were referred. At initial consultation, patients had a median ECOG PS 1, median age 48 years (range 18-70); 69% were men, 76% had glioblastoma; 68% were on AEDs, 63% required steroid therapy; median number of prior treatments was two. Median OS for patients treated on a Ph1 trials was 9.3 months (95% CI 5.9-12.9) versus 5.3 months (95% CI 4.1-6.1) for patients that did not proceed with a Ph1 trial, p = 0.0094. Steroid use, poor PS, neutrophil-to-lymphocyte ratio and treatment on a Ph1 trial were shown to independently influence OS. CONCLUSIONS: We report a survival benefit for patients with PMBT treated on Ph1 trials. Toxicity and efficacy outcomes were comparable to the general Ph1 population. In the absence of an internationally recognized standard second line treatment for patients with recurrent PMBT, more Ph1 trials should allow enrolment of patients with refractory PMBT and Ph1 trial participation should be considered at an earlier stage.

Clinical safety and activity of pembrolizumab in patients with malignant pleural mesothelioma (KEYNOTE-028): preliminary results from a non-randomised, open-label, phase 1b trial.

BACKGROUND: Malignant pleural mesothelioma is a highly aggressive cancer with poor prognosis and few treatment options following progression on platinum-containing chemotherapy. We assessed the safety and efficacy of pembrolizumab (an anti-programmed cell death receptor 1 [PD-1] antibody) in advanced solid tumours expressing programmed cell death ligand 1 (PD-L1) and report here on the interim analysis of the malignant pleural mesothelioma cohort. METHODS: Previously treated patients with PD-L1-positive malignant pleural mesothelioma were enrolled from 13 centres in six countries. Patients received pembrolizumab (10 mg/kg every 2 weeks) for up to 2 years or until confirmed progression or unacceptable toxicity. Key eligibility criteria included measurable disease, failure of standard therapy, and Eastern Cooperative Oncology Group performance status of 0 or 1. PD-L1 positivity was defined as expression in 1% or more of tumour cells by immunohistochemistry. Response was assessed based on investigator review using the Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1). Primary endpoints were safety and tolerability, analysed in the all-patients-as-treated population, and objective response, analysed for the full-analysis set. This trial is registered with ClinicalTrials.gov, number NCT02054806, and is ongoing but not recruiting participants. FINDINGS: As of June 20, 2016, 25 patients received pembrolizumab. 16 (64%) patients reported a treatment-related adverse event; the most common adverse event were fatigue (six [24%]), nausea (six [24%]), and arthralgia (five [20%]). Five (20%) patients reported grade 3 treatment-related adverse events. Three (12%) patients required dose interruption because of immune-related adverse events: one (4%) of 25 each had grade 3 rhabdomyolysis and grade 2 hypothyroidism; grade 3 iridocyclitis, grade 1 erythema multiforme, and grade 3 erythema; and grade 2 infusion-related reaction. No treatment-related deaths or discontinuations occurred. Five (20%) patients had a partial response, for an objective response of 20% (95% CI 6·8-40·7), and 13 (52%) of 25 had stable disease. Responses were durable (median response duration 12·0 months [95% CI 3·7 to not reached]); two patients remained on treatment at data cutoff. INTERPRETATION: Pembrolizumab appears to be well tolerated and might confer anti-tumour activity in patients with PD-L1-positive malignant pleural mesothelioma. Response durability and efficacy in this patient population warrants further investigation. FUNDING: Merck.

A study of motivations and expectations of patients seen in phase 1 oncology clinics.

BACKGROUND: To better inform clinical practice, this study was aimed at capturing patients' motivations for enrolling in phase 1 trials and at quantifying their expectations of the benefits, risks, and commitment associated with clinical trials and the impact of the initial consultation on their expectations. METHODS: This was a single-center, prospective, quantitative study of newly referred adult patients considering their first phase 1 oncology trial. Participants completed questionnaires before they were seen and an abbreviated follow-up version after their consultation. RESULTS: Questionnaires were completed by 396 (99%) and 301 (76%) before and after the clinic, respectively. Participants ranked the possibility of tumor shrinkage (84%) as the most important motivation for considering a phase 1 trial; this was followed by no alternative treatments (56%), their physician's recommendation (44%), and the fact that the research might benefit others (38%). When they were asked about the potential personal benefit, 43% predicted tumor shrinkage initially. After the consultation, this increased to 47%. Fourteen percent of patients expected a cure. When asked about risks, 71% of the participants expected moderate side effects. When asked about expectations of time commitments, a majority of patients did not anticipate weekly visits, although this was understood by 93% of patients after the consultation. Overall, patients were keen to consider trials and when asked before and after the consultation 72% and 84% were willing to enroll in studies, respectively. CONCLUSIONS: This study reports that more than 80% of patients enroll in early-phase clinical oncology trials motivated by the potential of a clinical benefit, with approximately half expecting tumor shrinkage and approximately a tenth anticipating a cure. The typical phase 1 response rate is 4% to 20%, and this discrepancy exemplifies the challenges faced by patients and healthcare professionals during their interactions for phase 1 studies. Cancer 2016;122:3501-3508. © 2016 American Cancer Society.