Evaluating niraparib versus active symptom control in patients with previously treated mesothelioma (NERO): a study protocol for a multicentre, randomised, two-arm, open-label phase II trial in UK secondary care centres.

BACKGROUND: Malignant mesothelioma is a rapidly lethal cancer that has been increasing at an epidemic rate over the last three decades. Targeted therapies for mesothelioma have been lacking. A previous study called MiST1 (NCT03654833), evaluated the efficacy of Poly (ADP-ribose) polymerase (PARP) inhibition in mesothelioma. This study met its primary endpoint with 15% of patients having durable responses exceeding 1 year. Therefore, there is a need to evaluate PARP inhibitors in relapsed mesothelioma patients, where options are limited. Niraparib is the PARP inhibitor used in NERO. METHODS: NERO is a multicentre, two-arm, open-label UK randomised phase II trial designed to evaluate the efficacy of PARP inhibition in relapsed mesothelioma. 84 patients are being recruited. NERO is not restricted by line of therapy; however, eligible participants must have been treated with an approved platinum based systemic therapy. Participants will be randomised 2:1, stratified according to histology and response to prior platinum-based chemotherapy, to receive either active symptom control (ASC) and niraparib or ASC alone, for up to 24 weeks. Participants will be treated until disease progression, withdrawal, death or development of significant treatment limiting toxicity. Participants randomised to niraparib will receive 200 or 300 mg daily in a 3-weekly cycle. The primary endpoint is progression-free survival, where progression is determined by modified Response Evaluation Criteria in Solid Tumors (mRECIST) or RECIST 1.1; investigator reported progression; or death from any cause, whichever comes first. Secondary endpoints include overall survival, best overall response, 12-week and 24 week disease control, duration of response, treatment compliance and safety/tolerability. If NERO shows niraparib to be safe and biologically effective, it may lead to future late phase randomised controlled trials in relapsed mesothelioma. ETHICS AND DISSEMINATION: The study received ethical approval from London-Hampstead Research Ethics Committee on 06-May-2022 (22/LO/0281). Data from all centres will be analysed together and published as soon as possible. TRIAL REGISTRATION NUMBER: ISCRTN16171129; NCT05455424.

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.

CONFIRM: a double-blind, placebo-controlled phase III clinical trial investigating the effect of nivolumab in patients with relapsed mesothelioma: study protocol for a randomised controlled trial.

BACKGROUND: Mesothelioma is an incurable, apoptosis-resistant cancer caused in most cases by previous exposure to asbestos and is increasing in incidence. It represents a growing health burden but remains under-researched, with limited treatment options. Early promising signals of activity relating to both PD-L1- and PD-1-targeted treatment in mesothelioma implicate a dependency of mesothelioma on this immune checkpoint. There is a need to evaluate checkpoint inhibitors in patients with relapsed mesothelioma where treatment options are limited. METHODS: The addition of 12 months of nivolumab (anti-PD1 antibody) to standard practice will be conducted in the UK using a randomised, placebo-controlled phase III trial (the Cancer Research UK CONFIRM trial). A total of 336 patients with pleural or peritoneal mesothelioma who have received at least two prior lines of therapy will be recruited from UK secondary care sites. Patients will be randomised 2:1 (nivolumab:placebo), stratified according to epithelioid/non-epithelioid, to receive either 240 mg nivolumab monotherapy or saline placebo as a 30-min intravenous infusion. Treatment will be for up to 12 months. We will determine whether the use of nivolumab increases overall survival (the primary efficacy endpoint). Secondary endpoints will include progression-free survival, objective response rate, toxicity, quality of life and cost-effectiveness. Analysis will be performed according to the intention-to-treat principle using a Cox regression analysis for the primary endpoint (and for other time-to-event endpoints). DISCUSSION: The outcome of this trial will provide evidence of the potential benefit of the use of nivolumab in the treatment of relapsed mesothelioma. If found to be clinically effective, safe and cost-effective it is likely to become the new standard of care in the UK. TRIAL REGISTRATION: EudraCT Number: 2016-003111-35 (entered on 21 July 2016); ClinicalTrials.gov, ID: NCT03063450 . Registered on 24 February 2017.