In-vitro assays for immuno-oncology drug efficacy assessment and screening for personalized cancer therapy: scopes and challenges.

INTRODUCTION: Immunotherapies have revolutionized cancer treatment, but often fail to produce desirable therapeutic outcomes in all patients. Due to the inter-patient heterogeneity and complexity of the tumor microenvironment, personalized treatment approaches are gaining demand. Researchers have long been using a range of in-vitro assays including 2D models, organoid co-cultures, and cancer-on-a-chip platforms for cancer drug screening. A comparative analysis of these assays with their suitability, high-throughput capacity, and clinical translatability is required for optimal translational use. AREAS COVERED: The review summarized in-vitro platforms with their comparative advantages and limitations including construction strategies, and translational potential for immuno-oncology drug efficacy assessment. We also discussed end-point analysis strategies so that researchers can contextualize their usefulness and optimally design experiments for personalized immunotherapy efficacy prediction. EXPERT OPINION: Researchers developed several in-vitro platforms that can provide information on personalized immunotherapy efficacy from different angles. Image-based assays are undoubtedly more suitable to gather a wide range of information including cellular morphology and phenotypical behaviors but need significant improvement to overcome issues including background noise, sample preparation difficulty, and long duration of experiment. More studies and clinical trials are needed to resolve these issues and validate the assays before they can be used in real-life scenarios.

A three-arm randomised phase II study of the MEK inhibitor selumetinib alone or in combination with paclitaxel in metastatic uveal melanoma.

AIMS: The MAPK pathway is constitutively activated in uveal melanoma (UM). Selumetinib (AZD6244, ARRY-142886), a MEK inhibitor, has shown limited activity as monotherapy in metastatic UM. Pre-clinical studies support synergistic cytotoxic activity for MEK inhibitors combined with taxanes, and here we sought to assess the clinical efficacy of combining selumetinib and paclitaxel. PATIENTS AND METHODS: Seventy-seven patients with metastatic UM who had not received prior chemotherapy were randomised to selumetinib alone, or combined with paclitaxel with or without interruption in selumetinib two days before paclitaxel. The primary endpoint was progression free survival (PFS). After amendment, the combination arms were combined for analysis and the sample size adjusted to detect a hazard ratio (HR): 0.55, 80% power at 1-sided 5% significance level. RESULTS: The median PFS in the combination arms was 4.8 months (95% CI: 3.8 - 5.6) compared with 3.4 months (2.0 - 3.9) in the selumetinib arm (HR 0.62 [90% CI 0.41 - 0.92], 1-sided p-value = 0.022). ORR was 14% and 4% in the combination and monotherapy arms respectively. Median OS was 9 months for the combination and was not significantly different from selumetinib alone (10 months) with HR of 0.98 [90% CI 0.58 - 1.66], 1-sided p-value = 0.469. Toxicity was in keeping with the known profiles of the agents involved. CONCLUSIONS: SelPac met its primary endpoint, demonstrating an improvement in PFS for combination selumetinib and paclitaxel. No improvement in OS was observed, and the modest improvement in PFS is not practice changing.

A randomised phase 2 study of intermittent versus continuous dosing of dabrafenib plus trametinib in patients with BRAFV600 mutant advanced melanoma (INTERIM).

BACKGROUND: BRAF+MEK inhibitors extend life expectancy of patients with BRAFV600 mutant advanced melanoma. Acquired resistance limits duration of benefit, but preclinical and case studies suggest intermittent dosing could overcome this limitation. INTERIM was a phase 2 trial evaluating an intermittent dosing regimen. METHODS: Patients with BRAFV600 mutant advanced melanoma due to start dabrafenib+trametinib were randomised to receive either continuous (CONT), or intermittent (INT; dabrafenib d1-21, trametinib d1-14 every 28 days) dosing. A composite primary endpoint included progression-free survival (PFS) and quality of life (QoL). Secondary endpoints included response rate (ORR), overall survival (OS) and adverse events (AEs). Mutant BRAFV600E ctDNA was measured by droplet digital PCR (ddPCR), using mutant allele frequency of > 1 % as the detection threshold. RESULTS: 79 patients (39 INT, 40 CONT) were recruited; median age 67 years, 65 % AJCC (7th ed) stage IV M1c, 29 % had brain metastases. With 19 months median follow-up, INT was inferior in all efficacy measures: median PFS 8.5 vs 10.7mo (HR 1.39, 95 %CI 0.79-2.45, p = 0.255); median OS 18.1mo vs not reached (HR 1.69, 95 %CI 0.87-3.28, p = 0.121), ORR 57 % vs 77 %. INT patients experienced fewer treatment-related AEs (76 % vs 88 %), but more grade > 3 AEs (53 % vs 42 %). QoL favoured CONT. Detection of BRAFV600E ctDNA prior to treatment correlated with worse OS (HR 2.55, 95 %CI 1.25-5.21, p = 0.01) in both arms. A change to undetected during treatment did not significantly predict better OS. CONCLUSION: INTERIM findings are consistent with other recent clinical trials reporting that intermittent dosing does not improve efficacy of BRAF+MEK inhibitors.

Exercise to transform tumours from cold to hot and improve immunotherapy responsiveness.

Exercise provides significant health benefits to patients diagnosed with cancer including improved survival outcomes, quality of life and reduced cancer recurrence. Across multiple murine cancer models, aerobic exercise and resistance training has exhibited anti-tumour properties illustrated by inhibited tumour growth, reduced metastatic potential and modulation of the tumour microenvironment to allow the recognition and destruction of cancer cells. Clinical studies have demonstrated the rapid mobilisation and circulatory release of mature lymphoid populations, myokines and cytokines that occurs with exercise along with tumour vasculature normalisation. Tumour microenvironments enriched with immune cells with anti-cancer potential, such as CD8+ T cells, are termed 'hot', whilst those favouring an immunosuppressive environment and lacking in effector immune cells are classed as 'cold'. Pre-clinical evidence suggests exercise training has the potential to reprogramme cold tumours to become hot, although this requires validation in clinical studies. This hot environment could potentiate immunotherapy responsiveness, improving survival outcomes of patients undergoing cancer immunotherapy and allow those with typically cold tumours to benefit from immunotherapy. This review discusses the complex interactions between exercise and cancer, including exercise-induced alterations within the tumour microenvironment and systemic immunity. The potential role exercise may play in improving cancer immunotherapy responsiveness is explored. This review also highlights the need for translational studies exploring the role of exercise in patients with cancer with the potential to widen the spectrum of tumours that derive significant benefit from immunotherapy.

Ex-vivo drug screening of surgically resected glioma stem cells to replace murine avatars and provide personalise cancer therapy for glioblastoma patients.

With diminishing returns and high clinical failure rates from traditional preclinical and animal-based drug discovery strategies, more emphasis is being placed on alternative drug discovery platforms. Ex vivo approaches represent a departure from both more traditional preclinical animal-based models and clinical-based strategies and aim to address intra-tumoural and inter-patient variability at an earlier stage of drug discovery. Additionally, these approaches could also offer precise treatment stratification for patients within a week of tumour resection in order to direct tailored therapy. One tumour group that could significantly benefit from such ex vivo approaches are high-grade gliomas, which exhibit extensive heterogeneity, cellular plasticity and therapy-resistant glioma stem cell (GSC) niches. Historic use of murine-based preclinical models for these tumours has largely failed to generate new therapies, resulting in relatively stagnant and unacceptable survival rates of around 12-15 months post-diagnosis over the last 50 years. The near universal use of DNA damaging chemoradiotherapy after surgical resection within standard-of-care (SoC) therapy regimens provides an opportunity to improve current treatments if we can identify efficient drug combinations in preclinical models that better reflect the complex inter-/intra-tumour heterogeneity, GSC plasticity and inherent DNA damage resistance mechanisms. We have therefore developed and optimised a high-throughput ex vivo drug screening platform; GliExP, which maintains GSC populations using immediately dissociated fresh surgical tissue. As a proof-of-concept for GliExP, we have optimised SoC therapy responses and screened 30+ small molecule therapeutics and preclinical compounds against tumours from 18 different patients, including multi-region spatial heterogeneity sampling from several individual tumours. Our data therefore provides a strong basis to build upon GliExP to incorporate combination-based oncology therapeutics in tandem with SoC therapies as an important preclinical alternative to murine models (reduction and replacement) to triage experimental therapeutics for clinical translation and deliver rapid identification of effective treatment strategies for individual gliomas.

A Phase 1/2 trial of SRA737 (a Chk1 inhibitor) administered orally in patients with advanced cancer.

BACKGROUND: This was a first-in-human Phase 1/2 open-label dose-escalation study of the novel checkpoint kinase 1 (Chk1) inhibitor SRA737. METHODS: Patients with advanced solid tumours enrolled in dose-escalation cohorts and received SRA737 monotherapy orally on a continuous daily (QD) dosing schedule in 28-day cycles. Expansion cohorts included up to 20 patients with prospectively selected, pre-specified response predictive biomarkers. RESULTS: In total, 107 patients were treated at dose levels from 20-1300 mg. The maximum tolerated dose (MTD) of SRA737 was 1000 mg QD, the recommended Phase 2 dose (RP2D) was 800 mg QD. Common toxicities of diarrhoea, nausea and vomiting were generally mild to moderate. Dose-limiting toxicity at daily doses of 1000 and 1300 mg QD SRA737 included gastrointestinal events, neutropenia and thrombocytopenia. Pharmacokinetic analysis at the 800 mg QD dose showed a mean Cmin of 312 ng/mL (546 nM), exceeding levels required to cause growth delay in xenograft models. No partial or complete responses were seen. CONCLUSIONS: SRA737 was well tolerated at doses that achieved preclinically relevant drug concentrations but single agent activity did not warrant further development as monotherapy. Given its mechanism of action resulting in abrogating DNA damage repair, further clinical development of SRA737 should be as combination therapy. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov NCT02797964.

Mental health burden for NHS healthcare staff during the COVID-19 pandemic: First results of a longitudinal survey.

Background: The current investigation aimed to assess the mental health burden on healthcare workers during the early stages of the COVID-19 pandemic. Methods: A link to an online survey was sent to an estimate of 18,100 employees of Sheffield Teaching Hospitals NHS Foundation Trust (STH) who had access to email. The survey was completed between 2nd and June 12, 2020.1390 healthcare workers (medical, nursing, administrative and other professions) participated in the first survey. Data from a general population sample (n = 2025) was used for comparison. Severity of somatic symptoms was measured by the PHQ-15. Severity and probable diagnosis of depression, anxiety, and PTSD were measured by the PHQ-9, GAD-7, and ITQ. Linear and logistic regressions were performed to determine if population group predicted the severity of mental health outcomes, and probable diagnosis of depression, anxiety, and PTSD. Additionally, ANCOVAs were performed to compare mental health outcomes between occupational roles in HCWs. Analysis was performed using SPSS. Findings: Healthcare workers are more likely to experience greater severity of somatic symptoms, as well as severity and probable diagnosis of depression and anxiety, compared to the general population, but not increased traumatic stress symptoms. Scientific and technical, nursing and admin staff were more likely to experience worse mental health outcomes, compared to medical staff. Interpretation: The COVID-19 pandemic has led to increased mental health burden in some, but not all healthcare workers during the first acute phase of the pandemic. The findings from the current investigation provide valuable insights into which healthcare workers are particularly vulnerable to developing adverse mental health outcomes during and after a pandemic.

Assessment of RANK/RANK-L prevalence and clinical significance in NSCLC European Thoracic Oncology Platform Lungscape cohort and SPLENDOUR randomized clinical trial.

BACKGROUND: The primary objective of this study is to evaluate the clinical significance of RANK/L expression, in both a retrospective cohort of surgically resected stage I-III NSCLC (Lungscape) and a randomized clinical trial-cohort (SPLENDOUR) of advanced NSCLC treated with chemotherapy alone or in combination with denosumab. METHODS: RANK-L expression was assessed on tissue microarrays (TMAs) in Lungscape and whole sections in SPLENDOUR, using immunohistochemistry, with H-scores values > 0 indicating positivity. Prevalence of RANK positivity and its association with clinicopathological characteristics, and patient outcome was explored in a subset of the ETOP Lungscape cohort and in SPLENDOUR. Also investigated were the prevalence of RANK overexpression (proportion of positive cancer cells ≥ 50%) in the Lungscape cohort, and RANK-L in the SPLENDOUR trial. RESULTS: In the Lungscape cohort, RANK expression was assessed at a median follow-up of 46 months (N = 488 patients; 4 centers); 35% were female, 44/49/6% adenocarcinomas (AC)/squamous cell carcinomas (SCC)/other, 48/27/25% with stage I/II/III. Median RFS/TTR/OS were 58/Not reached/74 months. Prevalence of RANK expression was 31% (95%CI:27%-35%); significantly higher in AC: 50% (95%CI:43%-57%) vs SCC: 12% (95%CI:8%-16%) (p < 0.001); more frequent in females (42% vs 25%, p < 0.001) and tumors ≤ 4 cm (35.3% vs 23.3%, p = 0.0065). No association with outcome was found. In the SPLENDOUR trial (463 patients), the prevalence of membranous and cytoplasmic RANK positivity was 34% (95%CI:30%-38%) and 9% (95%CI:7%-12%), respectively, while prevalence for RANK-L was 5% (95%CI:3%-7%) and 36% (95%CI:31%-40%), respectively. Cytoplasmic RANK-L positivity was more common among females (47% vs 31%, p = 0.001) and in non-SCC histology (45% vs 10%, p < 0.0001). At the pre-specified 1% significance level, no prognostic or predictive effect was found. CONCLUSIONS: Both cohorts indicate that RANK expression is more common in adenocarcinoma/non-squamous NSCLC and in female patients. No prognostic effect is found, and in the clinical trial involving addition of denosumab to chemotherapy no predictive effect is detected.

Precision oncology using ex vivo technology: a step towards individualised cancer care?

Despite advances in cancer genomics and the increased use of genomic medicine, metastatic cancer is still mostly an incurable and fatal disease. With diminishing returns from traditional drug discovery strategies, and high clinical failure rates, more emphasis is being placed on alternative drug discovery platforms, such as ex vivo approaches. Ex vivo approaches aim to embed biological relevance and inter-patient variability at an earlier stage of drug discovery, and to offer more precise treatment stratification for patients. However, these techniques also have a high potential to offer personalised therapies to patients, complementing and enhancing genomic medicine. Although an array of approaches are available to researchers, only a minority of techniques have made it through to direct patient treatment within robust clinical trials. Within this review, we discuss the current challenges to ex vivo approaches within clinical practice and summarise the contemporary literature which has directed patient treatment. Finally, we map out how ex vivo approaches could transition from a small-scale, predominantly research based technology to a robust and validated predictive tool. In future, these pre-clinical approaches may be integrated into clinical cancer pathways to assist in the personalisation of therapy choices and to hopefully improve patient experiences and outcomes.

Olaparib maintenance versus placebo monotherapy in patients with advanced non-small cell lung cancer (PIN): A multicentre, randomised, controlled, phase 2 trial.

Background: Impaired double strand DNA repair by homologous repair deficiency (HRD) leads to sensitivity to poly ADP ribose polymerase (PARP) inhibition. Poly-ADP ribose polymerase (PARP) inhibitors target HRD to induce synthetic lethality and are used routinely in the treatment of BRCA1 mutated ovarian cancer in the platinum-sensitive maintenance setting. A subset of non-small cell lung cancers (NSCLCs) harbour impaired DNA double strand break repair. We therefore hypothesised that patients with metastatic non-small cell lung cancer exhibiting partial responses to platinum doublet-based chemotherapy, might enrich for impaired HRD, rendering these tumours more sensitive to inhibition of PARP inhibition by olaparib. Methods: The Olaparib Maintenance versus Placebo Monotherapy in Patients with Advanced Non-Small Cell Lung Cancer trial (PIN) was a multicentre double-blind placebo controlled randomised phase II screening trial. This study was conducted at 23 investigative hospital sites in the UK. Patients had advanced (stage IIIB/IV) squamous (Sq) or non-squamous (NSq) NSCLC, and had to be chemo-naive, European Cooperative Oncology Group (ECOG) performance status 0-1. Prior immunotherapy with a PD1 or PDL1 inhibitor was allowed. Patients could be registered for PIN prior to (stage 1), or after (stage 2) initiation of induction chemotherapy. If any tumour shrinkage was observed (any shrinkage of RECIST target lesions), following a minimum of 3 cycles of platinum doublet chemotherapy, patients were randomised 1:1 using a centralised online system, to either olaparib (300 mg twice daily by mouth in 21-day cycles) or placebo, which was continued until disease progression, or unacceptable toxicity. Intention to treat (ITT) analyses of the primary endpoint included all randomised participants. Per protocol (PP) safety analysis included all participants who received at least one dose of study drug. Primary endpoint was progression-free survival (PFS), with a one-sided p-value of 0.2 to demonstrate statistical significance. Hazard ratios (HR) for PFS were both unadjusted and adjusted for the randomisation balancing factors (smoking status and histology). The trial was registered with ClinicalTrials.gov (NCT01788332) and EudraCT (2012-003383-51). Findings: A total of 940 patients were assessed for stage 1 eligibility of whom 263 were registered between Feb 24, 2014 and Nov 7, 2017. 194 patients were excluded prior to stage 2 (no tumour shrinkage or unevaluable) and 70 were randomised; 32 (46%) to Olaparib and 38 (54%) to placebo. 4% (3/70) of patients randomised had a CR and 96% (67/70) had a PR (or other evidence of tumour response/mixed stable) during induction therapy. A total of 36 patients were registered in stage 2 only, i.e., post induction therapy. Intention to treat (ITT) unadjusted analysis showed a PFS hazard ratio (HR) of 0.83 (one-sided 80% CI upper limit 1.03, one-sided unadjusted log rank test p-value=0.23). ITT Cox-adjusted model showed a HR 0.73 (one-sided 80% CI upper limit 0.91, one sided p-value 0.11). Adverse events were reported in 31/32 subjects (97%) in the olaparib arm and 38/38 (100%) in the placebo group. The most commonly reported adverse events in the olaparib group were fatigue (20/31; 65%), nausea (17/31; 55%), anaemia (15/31; 48%) and dyspnea (13/31; 42%). In the placebo group the most common adverse events were fatigue (25/38; 66%), coughing (22/38; 58%), dyspnea (15/38; 39%) and nausea (11/38; 29%). There were no treatment-related deaths. Interpretation: PFS was longer in the olaparib arm, but this did not reach statistical significance. When the PFS HR was adjusted for smoking status and histology, a significant difference at the one-sided 0.2 level was observed, suggesting that tumour control may be achieved for chemosensitive NSCLC treated with PARP monotherapy. We speculate that this signal may be driven by a molecular subgroup harbouring HRD. Funding: This study was funded between AstraZeneca CRUK, National Cancer Research Institute, and Cancer Research UK Feasibility Study Committee.

Olaparib as maintenance treatment in patients with chemosensitive small cell lung cancer (STOMP): A randomised, double-blind, placebo-controlled phase II trial.

OBJECTIVES: Small cell lung cancer (SCLC) responds well to chemoradiotherapy but frequently relapses. Here, we evaluate activity and safety of the poly (adenosine diphosphate (ADP)-ribose) polymerase (PARP) inhibitor olaparib as maintenance treatment for patients with chemoresponsive SCLC. MATERIALS AND METHODS: Eligible patients had complete or partial response to first line chemotherapy or chemoradiotherapy for SCLC. Patients were randomised 2:2:1:1 to olaparib 300 mg twice a day (BD), olaparib 200 mg three times a day (TDS), placebo BD or placebo TDS. The primary outcome was progression-free survival time (PFS). The trial design had 80% power to detect a 3-month difference in median PFS based on a one-sided 5% significance level. Secondary outcome measures included overall survival time (OS), adverse events and quality of life. ISRCTN 73164486, EudraCT 2010-021165-76. RESULTS: 220 patients were randomised: 74 placebo, 73 olaparib BD, 73 olaparib TDS. Median PFS (90% confidence interval (CI)) was 2·5 (1·8, 3·7), 3·7 (3·1, 4·6) and 3·6 (2·8, 4·7) months in the placebo, olaparib BD and TDS arms, respectively. There was no significant difference in PFS between olaparib and placebo for either BD (Hazard Ratio (HR) (90%CI) 0·76 (0·57, 1·02), P = 0·125 or TDS 0·86, (0·64, 1·15), P = 0·402. Common adverse events on olaparib were fatigue, nausea, anaemia, vomiting and anorexia. Of 214 patients who discontinued treatment before 24 months, toxicity was the reason cited for 66 (18 placebo, 24 olaparib BD, 24 olaparib TDS). CONCLUSION: This trial does not provide sufficient evidence that either the BD or TDS regimen for maintenance olaparib monotherapy improves PFS or OS in an unselected SCLC population to warrant further research. Toxicity for olaparib was similar to other studies.

Inconsistencies in Modeling the Efficacy of the Oncolytic Virus HSV1716 Reveal Potential Predictive Biomarkers for Tolerability.

Treatment with HSV1716 via intralesional administration has proven successful for melanoma patients with the hope that oncolytic virotherapy would become another weapon in the systemic anticancer therapy (SACT) arsenal. In addition to challenges surrounding the systemic delivery of oncolytic viruses (OVs), problems associated with its in vivo modeling have resulted in low predictive power, contributing to the observed disappointing clinical efficacy. As OV's efficacy is elicited through interaction with the immune system, syngeneic orthotopic mouse models offer the opportunity to study these with high reproducibility and at a lower cost; however, inbred animals display specific immune characteristics which may confound results. The systemic delivery of HSV1716 was, therefore, assessed in multiple murine models of breast cancer. Tolerability to the virus was strain-dependent with C57/Bl6, the most tolerant and Balb/c experiencing lethal side effects, when delivered intravenously. Maximum tolerated doses were not enough to demonstrate efficacy against tumor growth rates or survival of Balb/c and FVB mouse models; therefore; the most susceptible strain (Balb/c mice) was treated with immunomodulators prior to virus administration in an attempt to reduce side effects. These studies demonstrate the number of variables to consider when modeling the efficacy of OVs and the complexities involved in their interpretation for translational purposes. By reporting these observations, we have potentially revealed a role for T-cell helper polarization in viral tolerability. Importantly, these findings were translated to human studies, whereby a Th1 cytokine profile was expressed in pleural effusions of patients that responded to HSV1716 treatment for malignant pleural mesothelioma with minimal side effects, warranting further investigation as a biomarker for predictive response.

Active symptom control with or without oral vinorelbine in patients with relapsed malignant pleural mesothelioma (VIM): A randomised, phase 2 trial.

Background: Currently, there is no US Food and Drug Administration approved therapy for patients with pleural mesothelioma who have relapsed following platinum-doublet based chemotherapy. Vinorelbine has demonstrated useful clinical activity in mesothelioma, however its efficacy has not been formally evaluated in a randomised setting. BRCA1 expression is required for vinorelbine induced apoptosis in preclinical models. Loss of expression may therefore correlate with vinorelbine resistance. Methods: In this randomised, phase 2 trial, patients were eligible if they met the following criteria: age ≥ 18 years, Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1, histologically confirmed pleural mesothelioma, post platinum-based chemotherapy, and radiological evidence of disease progression. Consented patients were randomised 2:1 to either active symptom control with oral vinorelbine versus active symptom control (ASC) every 3 weeks until disease progression, unacceptable toxicity or withdrawal at an initial dose of 60 mg/m2 increasing to 80 mg/m2 post-cycle 1. Randomisation was stratified by histological subtype, white cell count, gender, ECOG performance status and best response during first-line therapy. The study was open label. The primary endpoint was progression-free survival (PFS), measured from randomisation to time of event (or censoring). Analyses were carried out according to intention-to-treat (ITT) principles. Recruitment and trial follow-up are complete. This trial is registered with ClinicalTrials.gov, number NCT02139904. Findings: Between June 1, 2016 and Oct 31, 2018, we performed a randomised phase 2 trial in 14 hospitals in the United Kingdom. 225 patients were screened for eligibility, of whom 154 were randomly assigned to receive either ASC + vinorelbine (n = 98) or ASC (n = 56). PFS was significantly longer for ASC+vinorelbine compared with ASC alone; 4.2 months (interquartile range (IQR) 2.2-8.0) versus 2.8 months (IQR 1.4-4.1) for ASC, giving an unadjusted hazard ratio (HR) of 0·60 (80% CI upper limit 0.7, one-sided unadjusted log rank test p = 0.002); adjusted HR 0.6 (80% CI upper limit 0.7, one-sided adjusted log rank test p < 0.001). BRCA1 did not predict resistance to ASC+vinorelbine. Neutropenia was the most common grades 3, 4 adverse events in the ASC +vinorelbine arm. Interpretation: Vinorelbine plus ASC confers clinical benefit to patients with relapsed pleural mesothelioma who have progressed following platinum-based doublet chemotherapy. Funding: This study was funded by Cancer Research UK (grant CRUK A15569).

Nivolumab versus placebo in patients with relapsed malignant mesothelioma (CONFIRM): a multicentre, double-blind, randomised, phase 3 trial.

BACKGROUND: No phase 3 trial has yet shown improved survival for patients with pleural or peritoneal malignant mesothelioma who have progressed following platinum-based chemotherapy. The aim of this study was to assess the efficacy and safety of nivolumab, an anti-PD-1 antibody, in these patients. METHODS: This was a multicentre, placebo-controlled, double-blind, parallel group, randomised, phase 3 trial done in 24 hospitals in the UK. Adult patients (aged ≥18 years) with an Eastern Cooperative Oncology Group performance status of 0 or 1, with histologically confirmed pleural or peritoneal mesothelioma, who had received previous first-line platinum-based chemotherapy and had radiological evidence of disease progression, were randomly assigned (2:1) to receive nivolumab at a flat dose of 240 mg every 2 weeks over 30 min intravenously or placebo until disease progression or a maximum of 12 months. The randomisation sequence was generated within an interactive web response system (Alea); patients were stratified according to epithelioid versus non-epithelioid histology and were assigned in random block sizes of 3 and 6. Participants and treating clinicians were masked to group allocation. The co-primary endpoints were investigator-assessed progression-free survival and overall survival, analysed according to the treatment policy estimand (an equivalent of the intention-to-treat principle). All patients who were randomly assigned were included in the safety population, reported according to group allocation. This trial is registered with Clinicaltrials.gov, NCT03063450. FINDINGS: Between May 10, 2017, and March 30, 2020, 332 patients were recruited, of whom 221 (67%) were randomly assigned to the nivolumab group and 111 (33%) were assigned to the placebo group). Median follow-up was 11·6 months (IQR 7·2-16·8). Median progression-free survival was 3·0 months (95% CI 2·8-4·1) in the nivolumab group versus 1·8 months (1·4-2·6) in the placebo group (adjusted hazard ratio [HR] 0·67 [95% CI 0·53-0·85; p=0·0012). Median overall survival was 10·2 months (95% CI 8·5-12·1) in the nivolumab group versus 6·9 months (5·0-8·0) in the placebo group (adjusted HR 0·69 [95% CI 0·52-0·91]; p=0·0090). The most frequently reported grade 3 or worse treatment-related adverse events were diarrhoea (six [3%] of 221 in the nivolumab group vs two [2%] of 111 in the placebo group) and infusion-related reaction (six [3%] vs none). Serious adverse events occurred in 90 (41%) patients in the nivolumab group and 49 (44%) patients in the placebo group. There were no treatment-related deaths in either group. INTERPRETATION: Nivolumab represents a treatment that might be beneficial to patients with malignant mesothelioma who have progressed on first-line therapy. FUNDING: Stand up to Cancer-Cancer Research UK and Bristol Myers Squibb.

Combined, patient-level, analysis of two randomised trials evaluating the addition of denosumab to standard first-line chemotherapy in advanced NSCLC - The ETOP/EORTC SPLENDOUR and AMGEN-249 trials.

INTRODUCTION: The efficacy of adding denosumab to standard first-line chemotherapy for advanced NSCLC patients has been evaluated in two separate randomised trials (SPLENDOUR and AMGEN-249). In this pooled analysis, we will assess the combination-treatment effect in the largest available population, in order to conclude about the potential impact of denosumab in NSCLC. METHODS: Both trials included in this combined analysis, were randomised (SPLENDOUR 1:1, AMGEN-249 2:1) multi-centre trials stratified by histology, bone metastasis, geographical region and for SPLENDOUR only, ECOG PS. Cox proportional hazards models, were used to assess the treatment effect with respect to overall survival (OS; primary endpoint) and progression-free survival (PFS; secondary endpoint). Heterogeneity between trials was assessed, and subgroup analyses were performed. RESULTS: The pooled analysis was based on 740 randomised patients (SPLENDOUR:514; AMGEN-249:226), with 407 patients in the chemotherapy-denosumab arm and 333 in the chemotherapy-alone arm. In the chemotherapy-denosumab arm, at a median follow-up of 22.0 months, 277 (68.1%) deaths were reported with median OS 9.2 months (95%CI:[8.0-10.7]), while in the chemotherapy-alone arm, with similar median follow-up of 20.3 months, 230 (69.1%) deaths with median OS 9.9 months (95%CI:[8.2-11.2]). No significant denosumab effect was found (HR = 0.98; 95%CI:[0.82-1.18]; P = 0.85). Among subgroups, interaction was found between treatment and histology subtypes (P = 0.020), with a statistically significant benefit in the squamous group (HR = 0.70; 95%CI:[0.49-0.98]; P = 0.038), from 7.6 to 9.0 months median OS. With respect to PFS, 363 (89.2%) and 298 (89.5%) events were reported in the chemotherapy-denosumab and chemotherapy-alone arms, respectively, with corresponding medians 4.8 months (95%CI:[4.4-5.3]) and 4.9 months (95%CI:[4.3-5.4]). HR for PFS was 0.97(95%CI:[0.83-1.15]; P = 0.76), indicating that no significant denosumab benefit existed for PFS. CONCLUSION: In this pooled analysis, no statistically significant improvement was shown in PFS/OS with the combination of denosumab and chemotherapy for advanced NSCLC and no meaningful benefit in any of the subgroups.

The DANTE trial protocol: a randomised phase III trial to evaluate the Duration of ANti-PD-1 monoclonal antibody Treatment in patients with metastatic mElanoma.

BACKGROUND: Immunotherapy is revolutionising the treatment of patients diagnosed with melanoma and other cancers. The first immune checkpoint inhibitor, ipilimumab (targeting cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4)), showed a survival advantage over standard chemotherapy. Subsequently the anti-programmed cell death protein 1 (PD-1) antibodies, nivolumab and pembrolizumab were shown to be more effective than ipilimumab. Ipilimumab combined with nivolumab gives an incremental gain in overall survival compared with nivolumab alone but increases the risk of severe, potentially life-threatening toxicities. In contrast to ipilimumab monotherapy, anti-PD-1 antibodies are licensed to be continued until disease progression. Follow-up of patients recruited to the first trials evaluating 2 years of pembrolizumab showed that three-quarters of responding patients continue responding after stopping treatment. Suggestive of early response, we hypothesised that continuing anti-PD-1 treatment beyond 1 year in progression-free patients may be unnecessary and so designed the DANTE trial. METHODS: DANTE is a multicentre, randomised, phase III, non-inferiority trial to evaluate the duration of anti-PD-1 therapy in patients with metastatic (unresectable stage III and stage IV) melanoma. It uses a two-stage recruitment strategy, registering patients before they complete 1 year of first-line anti-PD-1 +/- CTLA-4 therapy and randomising eligible patients who have received 12 months of treatment and are progression-free at 1 year. At randomisation, 1208 patients are assigned (1:1) to either 1) continue anti-PD-1 treatment until disease progression/ unacceptable toxicity/ for at least 2 years in the absence of disease progression/ unacceptable toxicity or 2) to stop treatment. Randomisation stratifies for baseline prognostic factors. The primary outcome is progression-free survival at 3, 6, 9 and 12 months and then, 6-monthly for up to 4-years. Secondary outcomes collected at all timepoints include overall survival, response-rate and duration and safety, with quality of life and cost-effectiveness outcomes collected 3-monthly for up to 18-months. Sub-studies include a qualitative analysis of patient acceptance of randomisation and sample collection to inform future translational studies into response/ toxicity biomarkers. DISCUSSION: DANTE is a unique prospective trial investigating the optimal duration of anti-PD-1 therapy in metastatic melanoma patients. Outcomes will inform future use of these high burden drugs. TRIAL REGISTRATION: ISRCTN15837212 , 31 July 2018.

Phase I Trial of DNA Methyltransferase Inhibitor Guadecitabine Combined with Cisplatin and Gemcitabine for Solid Malignancies Including Urothelial Carcinoma (SPIRE).

PURPOSE: Preclinical data indicate that DNA methyltransferase inhibition will circumvent cisplatin resistance in various cancers. PATIENT AND METHODS: SPIRE comprised a dose-escalation phase for incurable metastatic solid cancers, followed by a randomized dose expansion phase for neoadjuvant treatment of T2-4a N0 M0 bladder urothelial carcinoma. The primary objective was a recommended phase II dose (RP2D) for guadecitabine combined with gemcitabine and cisplatin. Treatment comprised 21-day gemcitabine and cisplatin cycles (cisplatin 70 mg/m2, i.v., day 8 and gemcitabine 1,000 mg/m2, i.v., days 8 + 15). Guadecitabine was injected subcutaneously on days 1-5, within escalation phase cohorts, and to half of 20 patients in the expansion phase. Registration ID: ISRCTN 16332228. RESULTS: Within the escalation phase, dose-limiting toxicities related predominantly to myelosuppression requiring G-CSF prophylaxis from cohort 2 (guadecitabine 20 mg/m2, days 1-5). The most common grade ≥3 adverse events in 17 patients in the dose-escalation phase were neutropenia (76.5%), thrombocytopenia (64.7%), leukopenia (29.4%), and anemia (29.4%). Addition of guadecitabine to gemcitabine and cisplatin in the expansion phase resulted in similar rates of severe hematologic adverse events, similar cisplatin dose intensity, but modestly reduced gemcitabine dose intensity. Radical treatment options after chemotherapy were not compromised. Pharmacodynamics evaluations indicated guadecitabine maximal target effect at the point of cisplatin administration. Pharmacokinetics were consistent with prior data. No treatment-related deaths occurred. CONCLUSIONS: The guadecitabine RP2D was 20 mg/m2, days 1-5, in combination with gemcitabine and cisplatin and required GCSF prophylaxis. Gene promoter methylation pharmacodynamics are optimal with this schedule. Addition of guadecitabine to gemcitabine and cisplatin was tolerable, despite some additional myelosuppression, and warrants further investigation to assess efficacy.