Differences in cancer clinical trial activity and trial characteristics at metropolitan and rural trial sites in Victoria, Australia.

OBJECTIVE: Cancer clinical trials (CCTs) provide access to emerging therapies and extra clinical care. We aimed to describe the volume and characteristics of CCTs available across Victoria, Australia, and identify factors associated with rural trial location. METHODS: Quantitative analysis of secondary data from Cancer Council Victoria's Clinical Trials Management Scheme dataset. DESIGN: A cross-sectional study design was used. SETTING: CCTs were available Victoria-wide in 2018. PARTICIPANTS: There were 1669 CCTs and 5909 CCT participants. MAIN OUTCOME MEASURES: Rural CCT location was assessed as a binary variable with categories of 'yes' (modified Monash [MM] categories 2-7) and 'no' (MM category 1). MM categories were determined from postcodes. The highest ('least rural') MM category was used for postcodes with multiple MM categories. RESULTS: Of 1669 CCTs, 168 (10.1%) were conducted in rural areas. Of 5909 CCT participants, 315 (5.3%) participated in rural CCTs. There were 526 CCTs (31.5%) with 1907 (32.3%) newly enrolled participants. Of 1892 newly enrolled participants with postcode data, 488 (25.8%) were rural residents. Of them, 368 (75.4%) participated in metropolitan CCTs. In a multivariable logistic regression analysis for all 1669 CCTs, odds of a rural rather than metropolitan CCT location were significantly (p-value <0.05) lower for early-phase than late-phase trials and non-solid than solid tumour trials but significantly (p-value <0.05) higher for non-industry than industry-sponsored trials. CONCLUSIONS: In Victoria, 10% of CCTs are at rural sites. Most rural-residing CCT participants travel to metropolitan sites, where there are more late-phase, non-solid-tumour and industry-sponsored trials. Approaches to increase the volume and variety of rural CCTs should be considered.

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.

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.

Immuno-oncology combinations: raising the tail of the survival curve.

There have been exponential gains in immuno-oncology in recent times through the development of immune checkpoint inhibitors. Already approved by the U.S. Food and Drug Administration for advanced melanoma and non-small cell lung cancer, immune checkpoint inhibitors also appear to have significant antitumor activity in multiple other tumor types. An exciting component of immunotherapy is the durability of antitumor responses observed, with some patients achieving disease control for many years. Nevertheless, not all patients benefit, and efforts should thus now focus on improving the efficacy of immunotherapy through the use of combination approaches and predictive biomarkers of response and resistance. There are multiple potential rational combinations using an immunotherapy backbone, including existing treatments such as radiotherapy, chemotherapy or molecularly targeted agents, as well as other immunotherapeutics. The aim of such antitumor strategies will be to raise the tail on the survival curve by increasing the number of long term survivors, while managing any additive or synergistic toxicities that may arise with immunotherapy combinations. Rational trial designs based on a clear understanding of tumor biology and drug pharmacology remain paramount. This article reviews the biology underpinning immuno-oncology, discusses existing and novel immunotherapeutic combinations currently in development, the challenges of predictive biomarkers of response and resistance and the impact of immuno-oncology on early phase clinical trial design.

Current and advancing systemic treatment options for soft tissue sarcomas.

INTRODUCTION: Soft tissue sarcomas are a collection of rare malignancies, the treatment of which has evolved over time. Although cytotoxic chemotherapy remains the cornerstone of management of metastatic disease, many new treatments have been developed or show great promise in the treatment of soft tissue sarcoma. Research into the different underlying pathogenesis of individual subtypes has driven progress in treatment. This has allowed development of treatments targeted to specific subtypes of sarcoma. AREAS COVERED: We provide a review of the current field of systemic therapy in soft tissue sarcoma. This is followed by an in-depth analysis of recent developments in treatment, as well as new treatments that are aimed at specific subtypes of sarcoma, and the biological rationale behind these therapies. We also look in detail at the promising new agents currently in development. EXPERT OPINION: Much progression has been made in treatment of soft tissue sarcomas with multiple exciting new treatments in development. However outcomes in general remain poor. Further research into the underlying pathogenesis of soft tissue sarcomas may help deliver more effective systemic therapies. Increased collaboration between basic science, translational and clinical investigators is required at national and international levels to maximise progress.