A matching-adjusted indirect comparison of combination nivolumab plus ipilimumab with BRAF plus MEK inhibitors for the treatment of BRAF-mutant advanced melanoma☆

Background

Approved first-line treatments for patients with BRAF V600–mutant advanced melanoma include nivolumab (a programmed cell death protein 1 inhibitor) plus ipilimumab (a cytotoxic T lymphocyte antigen-4 inhibitor; NIVO+IPI) and the BRAF/MEK inhibitors dabrafenib plus trametinib (DAB+TRAM), encorafenib plus binimetinib (ENCO+BINI), and vemurafenib plus cobimetinib (VEM+COBI). Results from prospective randomized clinical trials (RCTs) comparing these treatments have not yet been reported. This analysis evaluated the relative efficacy and safety of NIVO+IPI versus DAB+TRAM, ENCO+BINI, and VEM+COBI in patients with BRAF-mutant advanced melanoma using a matching-adjusted indirect comparison (MAIC).

Patients and methods

A systematic literature review identified RCTs for DAB+TRAM, ENCO+BINI, and VEM+COBI in patients with BRAF-mutant advanced melanoma. Individual patient-level data for NIVO+IPI were derived from the phase III CheckMate 067 trial (BRAF-mutant cohort) and restricted to match the inclusion/exclusion criteria of the comparator trials. Treatment effects for overall survival (OS) and progression-free survival (PFS) were estimated using Cox proportional hazards and time-varying hazard ratio (HR) models. Safety outcomes (grade 3 or 4 treatment-related adverse events) with NIVO+IPI and the comparators were compared.

Results

In the Cox proportional hazards analysis, NIVO+IPI showed improved OS compared with DAB+TRAM (HR = 0.53; 95% confidence interval [CI], 0.39-0.73), ENCO+BINI (HR = 0.60; CI, 0.42-0.85), and VEM+COBI (HR = 0.50; CI, 0.36-0.70) for the overall study period. In the time-varying analysis, NIVO+IPI was associated with significant improvements in OS and PFS compared with the BRAF/MEK inhibitors 12 months after treatment initiation. There were no significant differences between NIVO+IPI and BRAF/MEK inhibitor treatment from 0 to 12 months. Safety outcomes favored DAB+TRAM over NIVO+IPI, whereas NIVO+IPI was comparable to VEM+COBI.

Conclusion

Results of this MAIC demonstrated durable OS and PFS benefits for patients with BRAF-mutant advanced melanoma treated with NIVO+IPI compared with BRAF/MEK inhibitors, with the greatest benefits noted after 12 months.

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First-line treatments for BRAF V600-mutant melanoma include NIVO+IPI and BRAF/MEK inhibitors.

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Results from prospective RCTs comparing NIVO+IPI and BRAF/MEK inhibitors have not yet been reported.

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This MAIC evaluated NIVO+IPI versus BRAF/MEK inhibitors for BRAF-mutant advanced melanoma.

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OS and PFS benefits were noted with NIVO+IPI versus BRAF/MEK inhibitors beginning at 12 months.

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These findings may provide information relevant to the selection of treatments for BRAF-mutant advanced melanoma.

Ventilatory and chronotropic incompetence during incremental and constant load exercise in end-stage renal disease: a comparative physiology study

Maximal O₂ uptake is impaired in end-stage renal disease (ESRD), reducing quality of life and longevity. While determinants of maximal exercise intolerance are well defined, little is known of limitation during submaximal constant load exercise. By comparing individuals with ESRD and healthy controls, the aim of this exploratory study was to characterize mechanisms of exercise intolerance in participants with ESRD by assessing cardiopulmonary physiology at rest and during exercise. Resting spirometry and echocardiography were performed in 20 dialysis-dependent participants with ESRD (age: 59 ± 12 yr, 14 men and 6 women) and 20 healthy age- and sex-matched controls. Exercise tolerance was assessed with ventilatory gas exchange and central hemodynamics during a maximal cardiopulmonary exercise test and 30 min of submaximal constant load exercise. Left ventricular mass (292 ± 102 vs. 185 ± 83 g, P = 0.01) and filling pressure (E/e': 6.48 ± 3.57 vs. 12.09 ± 6.50 m/s, P = 0.02) were higher in participants with ESRD; forced vital capacity (3.44 ± 1 vs. 4.29 ± 0.95 L/min, P = 0.03) and peak O₂ uptake (13.3 ± 2.7 vs. 24.6 ± 7.3 mL·kg^-1·min^-1, P < 0.001) were lower. During constant load exercise, the relative increase in the arterial-venous O₂ difference (13 ± 18% vs. 74 ± 18%) and heart rate (32 ± 18 vs. 75 ± 29%) were less in participants with ESRD despite exercise being performed at a higher percentage of maximum minute ventilation (48 ± 3% vs. 39 ± 3%) and heart rate (82 ± 2 vs. 64 ± 2%). Ventilatory and chronotropic incompetence contribute to exercise intolerance in individuals with ESRD. Both are potential targets for medical and lifestyle interventions.

A systematic review and network meta-analysis of adjuvant therapy for curatively resected biliary tract cancers

Background

Recent randomized controlled trials (rcts) have contributed high-quality data about adjuvant therapy in curatively resected biliary tract cancer (btc); however, a standard approach to treating those patients still has not been developed.

Methods

We conducted a systematic review of published studies and abstracts up to and including June 2018, choosing rcts involving patients with btc receiving adjuvant chemotherapy after complete surgical resection. Network meta-analysis methods were used for indirect comparisons of overall survival (os) and relapse-free survival (rfs) for various adjuvant therapies.

Results

Five rcts were included in qualitative synthesis, and three rcts (bilcap, prodige 12-accord 18, and bcat) had data sufficient for inclusion in the meta-analysis. Results from the indirect comparison demonstrated no significant improvement in os for capecitabine compared with gemcitabine or with gemcitabine-oxaliplatin (gemox), the hazard ratios (hrs) being 0.82 [95% confidence interval (ci): 0.53 to 1.27] and 0.86 (95% ci: 0.56 to 1.34) respectively. Similarly, no significant improvement in rfs was observed for capecitabine compared with gemcitabine or gemox.

Conclusions

Although in the present analysis, we found no statistically significant improvements in os or rfs for capecitabine compared with gemox or gemcitabine, capecitabine can-until further prospective trials are completed-be considered the standard of care in the adjuvant setting based on a single randomized phase iii study.

Vismodegib for periocular basal cell carcinoma: an international multicentre case series

INTRODUCTION

Vismodegib (Erivedge, Genentech) is a first-in-class inhibitor of the hedgehog (Hh) pathway, which is licensed for use in locally advanced basal cell carcinoma (BCC) and metastatic BCC. The National Institute for Health and Care Excellence withdrew recommendation for use of vismodegib secondary to a lack of data comparing vismodegib to standard supportive care. The purpose of this multicentre, international case series is to report outcomes of patients with locally advanced periocular BCC who have been treated with vismodegib.

METHODS

The medical records of all patients treated with vismodegib were retrospectively reviewed across seven institutions in the United Kingdom, Australia, and New Zealand.

RESULTS

Thirteen patients were identified. Seven (54%) patients were male. All BCCs were ill-defined, with seven (58%) having orbital involvement at presentation. Median treatment time was 7 months (range 2-36 months). Eleven out of 13 patients developed side effects, the most common being fatigue in six patients (46%). Median follow-up was 24 months (range 12-48 months). Complete response was found in 5/13 patients (38%) and a partial response in 8/13 patients (62%). Six patients had further surgery after vismodegib, with three classed as globe-sparing operations. Three patients developed recurrence (23%). Three patients (23%) ultimately underwent exenteration.

DISCUSSION

This study demonstrates vismodegib to be a well-tolerated treatment which may, in some cases, facilitate globe-sparing surgery and hence avoid disfiguring operations such as exenteration. Uncertainty does remain regarding the long-term outcomes of patients treated with vismodegib.

The Application of Non-linear Flow Resistance in Cerebral Artery: Compared with Windkessel Model based on Genetic Algorithm

Continuous blood pressure is measured from various extracranial body sites, with difference in amplitude and phase with intracranial blood pressure. Consequent influences on the accuracy of Windkessel model need further investigation. Between blood pressure and intracranial flow rate, a model with non-linear flow resistance (R-DT) was proposed and compared with the 3-element Windkessel (RCR) model. From the measured blood flow velocity in middle cerebral artery, the blood pressure was estimated by R-DT and RCR models respectively. The parameters in the models were optimized by genetic algorithm. The accuracies of R-DT and RCR models were compared based on their estimation errors to the measured blood pressure. The capacitance element in RCR model indicated limited ability to take the time shift into account. Compared with RCR model, R-DT model had less error (averaged relative error: 5.19% and 2.49% for RCR and RDT models). The non-linear flow resistance was applicable in simulating cerebral arteries.

P5604Combining aortic size with measures of aortic stiffness and pulsatile hemodynamics enhances prediction of future thoracic aortic aneurysm expansion

Introduction

Thoracic aortic aneurysm (TAA) is a clinically silent disease which can lead to significant morbidity when complicated by an acute aortic syndrome. Although TAA size is the only variable used in decision-making, it is an imperfect predictor of risk. Conversely, hemodynamic measures that reflect the aorta's function, such as aortic stiffness and pulsatile hemodynamics, may provide additional insights into risk of TAA expansion.

Purpose

We hypothesized that combining aortic size with measures of arterial function (stiffness and pulsatile hemodynamics) would improve prediction of TAA expansion, as compared to aortic size alone.

Methods

105 unoperated participants with TAA were recruited between 2014 and 2017 and followed prospectively for ≥1 yr. TAA size was measured at enrolment and at the latest imaging study according to published consensus; TAA expansion was calculated as mm/year. Arterial function was non-invasively assessed at baseline with validated methods that integrate arterial tonometry with echocardiography. Multivariable linear regression assessed independent associations of baseline TAA size and each arterial function measure, initially separately and then in combination (by multiplying them when direction of association was the same, and dividing them when direction of association was opposite), with future TAA expansion. Standardized beta coefficients were calculated to allow direct comparisons. Models were adjusted for age, sex, body size, aneurysm location and etiology, type of imaging modality, follow-up time, mean arterial pressure, and history of hypertension, diabetes and smoking.

Results

Seventy-seven percent of participants were men, and the ratio of degenerative to heritable TAAs was 62/43. Mean ± SD age, baseline TAA size, and follow-up time were 62.8±11.3yrs, 46.3±3.9cm, and 2.2±0.7 years, respectively. Results of the multivariable linear regression models are summarized in the Table. While baseline TAA size and each arterial function measure were independently associated with TAA expansion, some of the arterial function measures were superior in predicting TAA growth (Table, left). In addition, combining aortic size and function further improved the prediction of TAA growth beyond each variable alone (Table, right).

Conclusion(s)

Combining aortic size with arterial function improved prediction of TAA expansion over any individual variable alone, independently of confounders. Assessing arterial function may confer a clinical advantage, when compared to current practice, in determining TAA disease activity and estimating one's TAA-related risk.

Acknowledgement/Funding

Canadian Institute of Health Research, Canadian Vascular Network, and Heart and Stroke Foundation of Canada

P4427Cardiovascular outcomes among runners of a marathon race - a 17 years' experience

Introduction

Over the past 17 years (2002–2018), 898,831 people participated in the Hong Kong Standard Chartered Marathon (HKSCM).

Purpose

We aim to study the incidence of marathon-related sudden cardiac arrest (SCA) and non-fatal myocardial injury (NFMI).

Methods

All the HKSCM related admissions between 2002 and 2017 were retrieved from the accident and emergency department admission records. We reviewed the data of HKSCM runners admitted for SCA and NFMI.

Results

Fourteen and thirty-nine runners were admitted for SCA (Mean age 38±13 years-old, 12 men) and NFMI (Mean age 42±12 years-old; 34 men) respectively.

Among the SCA runners, the arrest rhythms could not be retrieved in 3 cases. In the remaining 11 SCA runners, the arrest rhythms were ventricular fibrillation (VF) (N=6), pulseless-electrical activity (PEA) (N=3), and asystole (N=2). Nine of the 14 SCA runners were successfully resuscitated. Only 2 out of the 14 SCA runners had significant atherosclerotic coronary artery disease (CAD) requiring coronary angioplasty. Among the SCA runners, the etiologies of cardiac arrest were myocardial infarction (MI) (N=2), ischemic cardiomyopathy with VF (N=1), idiopathic VF (N=3), malignant coronary anomaly (N=1), and idiopathic (N=5). Percutaneous coronary intervention (PCI) was performed in 2 SCA runner with MI. Implantable cardioverter-defibrillators were implanted in 1 resuscitated runner with VF. Postmortem examination of the 3 deceased runners showed significant CAD in two and was unrevealing in one.

Among the 39 NFMI runners, coronary angiograms (CAG) or CT coronary angiogram were performed in 14 cases (36%), which showed minor CAD or unremarkable findings in 7 runners, and significant CAD in 7 runners. PCI and coronary artery bypass were performed in 5 and 2 NFMI runners respectively. Only 8 out of 39 NFMI runners reported chest pain. Significant ischemic ECG changes were detected in 9 out of 39 NFMI runners. Invasive CAGs were not performed in the remaining NFMI runners due to low pre-test likelihood of CAD and normal non-invasive test results.

Conclusions

The incidence of SCA and mortality among HKSCM runners was 1.56 per 100,000 and 0.56 per 100,000 respectively. The incidence of NFMI was 4.3 per 100,000. Coronary artery disease, coronary anomaly and idiopathic VF were the commonest etiologies of SCA.

2378Blunted stress myocardial oxygenation and not myocardial perfusion reserve is associated with arrhythmic risk in hypertrophic cardiomyopathy

Background

In hypertrophic cardiomyopathy (HCM), myocardial ischaemia is believed to play a role in fatal life-threatening ventricular arrhythmias and caused by microvascular dysfunction manifesting as impaired myocardial perfusion. However, previous studies suggest that myocardial oxygenation during vasodilator stress may also be blunted when perfusion is normal, due to increased metabolic demands conferred by energy-costly sarcomeric mutations, left ventricular hypertrophy and outflow obstruction. Whether or not impaired myocardial perfusion reserve or blunted stress oxygenation on cardiac magnetic resonance (CMR) predict the risk of ventricular arrhythmia in HCM is unknown.

Purpose

We sought to investigate if impaired myocardial perfusion reserve or stress oxygenation is associated with an increased risk of ventricular arrhythmia in HCM.

Methods

103 genotyped HCM patients (mean age 47±15 years) and 32 age- and sex-matched healthy controls underwent adenosine stress blood oxygen level dependent (BOLD) imaging, first pass perfusion and late gadolinium imaging (LGE) on CMR to assess stress oxygenation (BOLD ΔSI), myocardial perfusion reserve index (MPRI), and fibrosis respectively. All HCM patients were monitored for ventricular tachycardia (≥3 beats, ≥120 beats per minute) on a 24-hour Holter.

Results

As expected, MPRI was significantly reduced in HCM (1.5±0.4 vs 2.0±0.3, p<0.0001) compared to controls. Stress oxygenation response was blunted in HCM versus controls (9.1±4.1% vs 17.0±1.6%, p<0.0001, Figure 1B). Twenty-six (25%) patients developed ventricular tachycardia on Holter monitoring. On univariate analysis, only stress oxygenation and not MPRI associated with ventricular tachycardia. The prevalence of ventricular tachycardia in HCM increased with decreasing quartiles of stress oxygenation (Figure 1D). HCM patients in the lowest quartile of oxygenation (BOLD ΔSI <6.5%) were at a three-fold risk of ventricular tachycardia (OR 3.04, 95% confidence interval 1.02–9.05, p=0.04) on multivariable analysis (after adjusting for sudden cardiac death risk factors and LGE mass) compared to other patients. Sarcomeric mutation status was an independent determinant of stress oxygenation on multivariable analysis. Stress oxygenation was impaired in phenotype-negative sarcomeric mutation carriers (Sarc+P-, n=16) despite normal perfusion (Figure 1C, E). Sarcomeric HCM (Sarc+HCM) had more severe impairment in stress oxygenation than genotype negative HCM (G-HCM) and controls (Figure 1E).

Figure 1

Conclusion

In HCM, blunted stress-induced oxygenation is associated with an increased risk of ventricular arrhythmia and may represent a novel biomarker of arrhythmic risk. Sarcomeric mutation status is an important determinant of stress oxygenation response.

Acknowledgement/Funding

National Institute for Health Research Oxford Biomedical Centre and British Heart Foundation.

Impact of a novel prioritization framework on clinician-led oncology drug submissions

Background

In Canada, requests for public reimbursement of cancer drugs are predominately initiated by pharmaceutical manufacturers. Clinician-led submissions provide a mechanism to initiate the drug funding process when industry does not submit a request for funding consideration. Although such requests are resource-intensive to produce, Cancer Care Ontario (cco) has the capacity to facilitate clinician-led submissions. In 2014, cco began developing a cancer drug prioritization framework that allocates resources to systematically address a growing number of clinician-identified funding gaps with clinician-led submissions.

Methods

Cancer site-specific drug advisory committees established by cco consist of health care practitioners whose roles include identifying and prioritizing funding gaps. The committees submit their identified gaps to a cross-cancer-site prioritization exercise in which the requests are ranked based on a set of guiding principles derived from health technology assessment. The requests are then sequentially allocated the resources needed to meet submission requirements. Whether the funding gap is of provincial or pan-Canadian relevance determines where the submission is filed for assessment.

Results

Since its inception, the cco framework has identified 17 funding gaps in 9 cancer sites. In 4 prioritizations, the framework supported 6 submissions. As of June 2018, the framework had contributed to the eventual funding of more than 9 new drug-indication pairs, with more awaiting funding consideration.

Conclusions

The cco prioritization framework has enabled clinicians to effectively and systematically identify, prioritize, and fill funding gaps not addressed by industry. Ultimately, the framework helps to ensure that patients can access evidence-informed and cost-effective therapies. The framework will continue to evolve as it encounters new challenges, including funding requests for rare indications.