Implementing multi-level network meta-regression for time-to-event outcomes: A case study in relapsed refractory multiple myeloma

OBJECTIVES

Multi-level network meta-regression (ML-NMR) leverages individual patient data (IPD) and aggregate data (AD) from a network of randomized controlled trials (RCTs) to assess the comparative efficacy of multiple treatments, while adjusting for between-study differences. We provide an overview of ML-NMR for time-to-event outcomes and apply it to an illustrative case study, including example R code.

METHODS

The case study evaluated the comparative efficacy of idecabtagene vicleucel (ide-cel), selinexor+dexamethasone (Sd), belantamab mafodotin (BM), and conventional care (CC) for patients with triple class exposed relapsed/refractory multiple myeloma in terms of overall survival (OS). Single-arm clinical trials and real-world data were naively combined to create an AD artificial RCT (aRCT) (MAMMOTH-CC versus DREAMM-2-BM verus STORM-2-Sd) and an IPD aRCT (KarMMa-ide-cel versus KarMMa-RW-CC). With some assumptions, we incorporated continuous covariates with skewed distributions, reported as median and range. The ML-NMR models adjusted for number of prior lines, triple-class refractory (TCR) status, and age and were compared via the leave-one-out information criterion (LOOIC). We summarized predicted hazard ratios and survival (95% credible intervals) in the IPD aRCT population.

RESULTS

The Weibull ML-NMR model had the lowest LOOIC. Ide-cel was more efficacious than Sd, BM, and CC in terms of OS. Effect modifiers had minimal impact on the model and only TCR was a prognostic factor.

CONCLUSIONS

We demonstrate an application of ML-NMR for time-to-event outcomes and introduce code that can be used to aid implementation. Given its benefits, we encourage practitioners to utilize ML-NMR when population adjustment is necessary for comparisons of multiple treatments.

Unanchored Population-Adjusted Indirect Comparison Methods for Time-to-Event Outcomes Using Inverse Odds Weighting, Regression Adjustment, and Doubly Robust Methods With Either Individual Patient or Aggregate Data

OBJECTIVES

Several methods for unanchored population-adjusted indirect comparisons (PAICs) are available. Exploring alternative adjustment methods, depending on the available individual patient data (IPD) and the aggregate data (AD) in the external study, may help minimize bias in unanchored indirect comparisons. However, methods for time-to-event outcomes are not well understood. This study provides an overview and comparison of methods using a case study to increase familiarity. A recent method is applied to marginalize conditional hazard ratios, which allows for the comparisons of methods, and a doubly robust method is proposed.

METHODS

The following PAIC methods were compared through a case study in third-line small cell lung cancer, comparing nivolumab with standard of care based on a single-arm phase II trial (CheckMate 032) and real-world study (Flatiron) in terms of overall survival: IPD-IPD analyses using inverse odds weighting, regression adjustment, and a doubly robust method; IPD-AD analyses using matching-adjusted indirect comparison, simulated treatment comparison, and a doubly robust method.

RESULTS

Nivolumab extended survival versus standard of care with hazard ratios ranging from 0.63 (95% CI 0.44-0.90) in naive comparisons (identical estimates for IPD-IPD and IPD-AD analyses) to 0.69 (95% CI 0.44-0.98) in the IPD-IPD analyses using regression adjustment. Regression-based and doubly robust estimates yielded slightly wider confidence intervals versus the propensity score-based analyses.

CONCLUSIONS

The proposed doubly robust approach for time-to-event outcomes may help to minimize bias due to model misspecification. However, all methods for unanchored PAIC rely on the strong assumption that all prognostic covariates have been included.

A Comparison of Alternative Network Meta-Analysis Methods in the Presence of Nonproportional Hazards: A Case Study in First-Line Advanced or Metastatic Renal Cell Carcinoma

OBJECTIVES

Network meta-analysis (NMA) of time-to-event outcomes based on constant hazard ratios can result in biased findings when the proportional hazards (PHs) assumption does not hold in a subset of trials. We aimed to summarize the published non-PH NMA methods for time-to-event outcomes, demonstrate their application, and compare their results.

METHODS

The following non-PH NMA methods were compared through an illustrative case study in oncology of 4 randomized controlled trials in terms of progression-free survival and overall survival: (1) 1-step or (2) 2-step multivariate NMAs based on traditional survival distributions or fractional polynomials, (3) NMAs with restricted cubic splines for baseline hazard, and (4) restricted mean survival NMA.

RESULTS

For progression-free survival, the PH assumption did not hold across trials and non-PH NMA methods better reflected the relative treatment effects over time. The most flexible models (fractional polynomials and restricted cubic splines) fit better to the data than the other approaches. Estimated hazard ratios obtained with different non-PH NMA methods were similar at 5 years of follow-up but differed thereafter in the extrapolations. Although there was no strong evidence of PH violation for overall survival, non-PH NMA methods captured this uncertainty in the relative treatment effects over time.

CONCLUSIONS

When the PH assumption is questionable in a subset of the randomized controlled trials, we recommend assessing alternative non-PH NMA methods to estimate relative treatment effects for time-to-event outcomes. We propose a transparent and explicit stepwise model selection process considering model fit, external constraints, and clinical validity. Given inherent uncertainty, sensitivity analyses are suggested.

Structured expert elicitation to inform long-term survival extrapolations using alternative parametric distributions: a case study of CAR T therapy for relapsed/ refractory multiple myeloma

Background

Our aim was to extend traditional parametric models used to extrapolate survival in cost-effectiveness analyses (CEAs) by integrating individual-level patient data (IPD) from a clinical trial with estimates from experts regarding long-term survival. This was illustrated using a case study evaluating survival of patients with triple-class exposed relapsed/refractory multiple myeloma treated with the chimeric antigen receptor (CAR) T cell therapy idecabtagene vicleucel (ide-cel, bb2121) in KarMMa (a phase 2, single-arm trial).

Methods

The distribution of patients expected to be alive at 3, 5, and 10 years given the observed survival from KarMMa (13.3 months of follow-up) was elicited from 6 experts using the SHeffield ELicitation Framework. Quantities of interest were elicited from each expert individually, which informed the consensus elicitation including all experts. Estimates for each time point were assumed to follow a truncated normal distribution. These distributions were incorporated into survival models, which constrained the expected survival based on standard survival distributions informed by IPD from KarMMa.

Results

Models for ide-cel that combined KarMMa data with expert opinion were more consistent in terms of survival as well as mean survival at 10 years (survival point estimates under different parametric models were 29–33% at 3 years, 5–17% at 5 years, and 0–6% at 10 years) versus models with KarMMa data alone (11–39% at 3 years, 0–25% at 5 years, and 0–11% at 10 years).

Conclusion

This case study demonstrates a transparent approach to integrate IPD from trials with expert opinion using traditional parametric distributions to ensure long-term survival extrapolations are clinically plausible.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01745-z.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Indirect treatment comparison of idecabtagene vicleucel versus conventional care in triple-class exposed multiple myeloma

Aim: To compare the efficacy of idecabtagene vicleucel (ide-cel, bb2121) versus conventional care (CC) in triple-class exposed relapsed and refractory multiple myeloma (RRMM) patients. Patients & methods: A matching-adjusted indirect comparison was conducted using individual patient-level data from the pivotal, phase II, single-arm KarMMa trial (NCT03361748) and aggregate-level data from MAMMOTH, the largest independent observational study of CC in heavily pretreated RRMM patients. Results: Ide-cel improved overall response rate (odds ratio: 5.30; 95% CI: 2.96-9.51), progression-free survival (hazard ratio: 0.50; 95% CI: 0.36-0.70) and overall survival (hazard ratio: 0.37; 95% CI: 0.25-0.56) versus CC. Conclusion: These results suggest ide-cel offers improvements in clinical outcomes relative to CC in this heavily pretreated RRMM population.

Cost-effectiveness analysis of cemiplimab vs pembrolizumab for treatment of advanced cutaneous squamous cell carcinoma

BACKGROUND: Most cutaneous squamous cell carcinomas (CSCCs) can be treated with surgical excision or radiation; however, approximately 1% of patients develop advanced disease. In 2018, the FDA approved cemiplimab-rwlc as the first programmed cell death-1 (PD-1) monoclonal antibody for the treatment of patients with metastatic CSCC or locally advanced CSCC who are not candidates for curative surgery or curative radiation. In June 2020, pembrolizumab, another PD-1 monoclonal antibody, was approved for the treatment of patients with recurrent or metastatic CSCC who are not candidates for curative surgery or radiation. We previously reported on the cost-effectiveness of cemiplimab vs historical standard of care for the treatment of advanced CSCC from a US perspective. OBJECTIVE: To estimate the cost-effectiveness of cemiplimab vs pembrolizumab for patients with advanced CSCC in the United States. METHODS: A "partitioned survival" framework was used to assess the cost-effectiveness of cemiplimab vs pembrolizumab. Clinical inputs were based on the most recent data cut of the phase 2 trials for cemiplimab (EMPOWER-CSCC-1; NCT02760498) and pembrolizumab (KEYNOTE-629). Progression-free survival and overall survival were extrapolated using parametric models until all patients had progressed or died. Health state utilities were derived from data collected in the EMPOWER-CSCC-1 trial. Costs included drug acquisition, drug administration, disease management, terminal care, and adverse events and were based on published 2020 US list prices. To assess model uncertainty, 1-way sensitivity and probabilistic sensitivity analyses (PSA) were conducted, alongside scenario analyses evaluating key modeling assumptions. RESULTS: In the base case, cemiplimab resulted in an incremental gain of 3.44 life-years (discounted) and incremental cost-effectiveness ratio (ICER) of $130,329 per quality-adjusted life-year (QALY) vs pembrolizumab. At a willingness-to-pay threshold of $150,000/QALY, PSA indicated a 71% probability that cemiplimab is cost-effective when compared with pembrolizumab. Scenario analysis resulted in ICERs ranging from $115,909 to $187,374. CONCLUSIONS: Findings suggest that cemiplimab is a cost-effective treatment for patients with advanced CSCC, compared with pembrolizumab. These results should be interpreted cautiously in the absence of head-to-head trials; however, in the absence of such data, these results can be used to inform health care decisions over resource allocation. DISCLOSURES: This study was supported by Regeneron Pharmaceuticals, Inc., and Sanofi. Paul, Cope, Keeping, Mojebi, and Ayers are employees of PRECISIONheor, which received funding to produce this work. Chen, Kuznik, and Xu are employees and stockholders of Regeneron Pharmaceuticals, Inc. Sasane is an employee and stockholder of Sanofi, Inc. Konidaris, Atsou, and Guyot are employees of Sanofi, Inc. The authors were responsible for all content and editorial decisions and received no honoraria related to the development of this publication.

Budget impact (BI) analysis of cemiplimab-rwlc for advanced basal cell carcinoma (BCC) after hedgehog inhibitor (HHI) therapy in the United States

e18830

Background: A small proportion of patients (pts) with BCC develop advanced disease (locally advanced [la] and metastatic [m] BCC). Until recently, there was no standard treatment regimen for advanced BCC following progression on or intolerance to HHIs. Some pts received systemic therapy (ST), but most received best supportive care (BSC). Cemiplimab-rwlc is the first immunotherapy indicated in the US, fully for pts with laBCC and accelerated for mBCC, post HHIs or for whom HHIs are not appropriate. This study estimated the BI of introducing cemiplimab-rwlc in the US from a healthcare payer’s perspective. Methods: A decision analytic model was developed to estimate the BI of introducing cemiplimab-rwlc to a US healthcare system over 3 years for advanced BCC treatment following HHIs. Published data were used to estimate eligible patient population size. Reference case market shares for platinum chemotherapy (CT; 4%), nivolumab (3%), pembrolizumab (2%), vismodegib (1%), sonidegib (1%), and BSC (89%) were based on market research, as were predicted uptake of cemiplimab-rwlc and changes in market distribution of STs and BSC post-cemiplimab-rwlc launch, with most pts moving from BSC. Treatment costs were sourced from the ProspectoRx drug pricing database. Total costs (2020 US dollars [$]) to the healthcare system included costs related to treatment, disease monitoring, and mitigation of Grade 3–4 adverse events. Results: In a hypothetical US healthcare plan of 1,000,000 members, ̃32 pts per year with advanced BCC would be eligible for cemiplimab-rwlc, resulting in an average additional cost of cemiplimab-rwlc introduction of $0.12 per member per month (PMPM) over 3 years. The proportion of pts receiving ST rather than BSC was estimated to increase from 11% in 2020, prior to cemiplimab-rwlc approval, to 50% in 2023. Cemiplimab-rwlc market share is projected to increase by 41% by year 3 taking shares from BSC (–39%), HHIs (–1%), and CT (–1%). Given the large proportion of pts who currently receive BSC, the availability of cemiplimab-rwlc is expected to increase payers’ 3-year budget from $978,955 to $5,487,507 post-launch. A one-way sensitivity analysis showed that BI estimates were most sensitive to estimation of the size of the eligible population (health plan population [±20%], proportion of pts with advanced BCC [±20%], and those eligible for treatment post-HHI [±19%]), cemiplimab-rwlc treatment duration (±17%), and the cost of cemiplimab-rwlc (±17%). Changes to all other inputs had a < 5% impact. Conclusions: The introduction of cemiplimab-rwlc had a minimal BI on the average PMPM cost. Modest incremental BI is directly attributable to the projected uptake of cemiplimab-rwlc in a market where pts previously received no ST. These analyses provide new insights in the management of advanced BCC noting limited available evidence for post-HHI treatment.

Matching adjusted indirect comparisons of efficacy outcomes for idecabtagene vicleucel (ide-cel, bb2121) versus selinexor + dexamethasone and belantamab mafodotin in relapsed and refractory multiple myeloma

Idecabtagene vicleucel (ide-cel, bb2121), a chimeric antigen receptor (CAR) T cell therapy, has been investigated in patients with relapsed and refractory multiple myeloma (RRMM) who have received an immunomodulatory drug, proteasome inhibitor, and anti-CD38 antibody in the single-arm phase 2 KarMMa clinical trial. Two therapies with distinct mechanisms of action - selinexor plus dexamethasone (Sd) and belantamab mafodotin (BM) - are currently approved in the United States for heavily pretreated patients, including those who are triple-class refractory. To compare ide-cel versus Sd and ide-cel versus BM, matching-adjusted indirect comparisons were performed. Ide-cel extended progression-free survival (PFS) and overall survival (OS) versus both Sd and BM (hazard ratio (HR); 95% confidence interval (CI)). PFS: ide-cel versus Sd, 0.46; 0.28-0.75; ide-cel versus BM, 0.45; 0.27-0.77. OS: ide-cel versus Sd, 0.23; 0.13-0.42; ide-cel versus BM, 0.35; 0.14-0.87. These results suggest ide-cel offers clinically meaningful improvements over currently approved regimens for patients with heavily pretreated RRMM.

Assessing the Value of Cemiplimab for Adults With Advanced Cutaneous Squamous Cell Carcinoma: A Cost-Effectiveness Analysis

OBJECTIVES

To evaluate the cost-effectiveness of cemiplimab in patients with advanced cutaneous squamous cell carcinoma (CSCC) from a payer perspective in the United States.

METHODS

A partitioned survival model was developed to assess the cost-effectiveness of cemiplimab versus historical standard of care (SOC). All inputs were identified based on a systematic literature review, supplemented by expert opinion where necessary. Clinical inputs for cemiplimab were based on individual patient data from a cemiplimab phase 2 single-arm trial (NCT27060498). For SOC, analysis was based on a pooled analysis of single-arm clinical trials and retrospective studies evaluating chemotherapy and epidermal growth factor receptor inhibitors (cetuximab, erlotinib, and gefitinib) identified via a systematic literature review (6 of the 27 included studies). Overall survival and progression-free survival were extrapolated over a lifetime horizon. Costs were included for drug acquisition, drug administration, management of adverse events, subsequent therapy, disease management, and terminal care. Unit costs were based on published 2019 US list prices.

RESULTS

In the base case, cemiplimab versus SOC resulted in an incremental cost-effectiveness ratio of $99 447 per quality adjusted-life year (QALY), where incremental costs and QALYs were $372 108 and 3.74, respectively. At a willingness-to-pay threshold of $150 000/QALY, the probabilistic sensitivity analysis suggests a 90% probability that cemiplimab is cost-effective compared to SOC. Scenario analyses resulted in incremental cost-effectiveness ratios ranging from $90 590 to $148 738.

CONCLUSIONS

Compared with historical SOC, cemiplimab is a cost-effective use of US payer resources for the treatment of advanced CSCC and is expected to provide value for money.

Aligning text mining and machine learning algorithms with best practices for study selection in systematic literature reviews

BACKGROUND

Despite existing research on text mining and machine learning for title and abstract screening, the role of machine learning within systematic literature reviews (SLRs) for health technology assessment (HTA) remains unclear given lack of extensive testing and of guidance from HTA agencies. We sought to address two knowledge gaps: to extend ML algorithms to provide a reason for exclusion-to align with current practices-and to determine optimal parameter settings for feature-set generation and ML algorithms.

METHODS

We used abstract and full-text selection data from five large SLRs (n = 3089 to 12,769 abstracts) across a variety of disease areas. Each SLR was split into training and test sets. We developed a multi-step algorithm to categorize each citation into the following categories: included; excluded for each PICOS criterion; or unclassified. We used a bag-of-words approach for feature-set generation and compared machine learning algorithms using support vector machines (SVMs), naïve Bayes (NB), and bagged classification and regression trees (CART) for classification. We also compared alternative training set strategies: using full data versus downsampling (i.e., reducing excludes to balance includes/excludes because machine learning algorithms perform better with balanced data), and using inclusion/exclusion decisions from abstract versus full-text screening. Performance comparisons were in terms of specificity, sensitivity, accuracy, and matching the reason for exclusion.

RESULTS

The best-fitting model (optimized sensitivity and specificity) was based on the SVM algorithm using training data based on full-text decisions, downsampling, and excluding words occurring fewer than five times. The sensitivity and specificity of this model ranged from 94 to 100%, and 54 to 89%, respectively, across the five SLRs. On average, 75% of excluded citations were excluded with a reason and 83% of these citations matched the reviewers' original reason for exclusion. Sensitivity significantly improved when both downsampling and abstract decisions were used.

CONCLUSIONS

ML algorithms can improve the efficiency of the SLR process and the proposed algorithms could reduce the workload of a second reviewer by identifying exclusions with a relevant PICOS reason, thus aligning with HTA guidance. Downsampling can be used to improve study selection, and improvements using full-text exclusions have implications for a learn-as-you-go approach.

Comparative effectiveness of nivolumab versus standard of care for third-line patients with small-cell lung cancer

Aim: To estimate the comparative effectiveness of nivolumab versus standard of care (SOC) in terms of overall survival (OS) for small-cell lung cancer patients treated with two prior lines of chemotherapy, in other words, third line in the USA. Materials & methods: Data were from CheckMate 032, a single-arm trial of nivolumab, and real-world electronic patient records. Comparisons of OS were conducted using three different methods to adjust for differences (regression, weighting and doubly robust) between the populations. Results: Nivolumab was associated with longer survival compared with SOC (hazard ratio for OS: 0.58-0.70) across all methods for adjustment. Conclusion: Nivolumab was more efficacious in terms of OS as third-line treatment for small-cell lung cancer compared with current SOC in the USA.

Comparative efficacy of cemiplimab versus other systemic treatments for advanced cutaneous squamous cell carcinoma

Aim: To estimate the comparative efficacy of cemiplimab, a programmed cell death protein 1 inhibitor, versus EGFR inhibitors, pembrolizumab and platinum-based chemotherapy in terms of overall survival (OS) and progression-free survival. Patients & methods: We performed an indirect treatment comparison of cemiplimab and other available systemic therapies for patients with advanced cutaneous squamous cell carcinoma. Results: Cemiplimab was associated with benefits in OS (hazard ratios range: 0.07-0.52) and progression-free survival (hazard ratios range: 0.30-0.67) versus EGFR inhibitors and pembrolizumab (data from KEYNOTE-629). Cemiplimab was more efficacious versus platinum-based chemotherapy in terms of OS. Conclusion: Cemiplimab may offer improvements in survival for advanced cutaneous squamous cell carcinoma patients compared with existing systemic therapies.

Assessing the value of cemiplimab for adults with advanced cutaneous squamous cell carcinoma (CSCC): A cost-effectiveness analysis

e19397

Background: Cemiplimab is a high-affinity, human, hinge-stabilized, monoclonal antibody that potently blocks the interactions of programmed cell death-1 (PD-1) with programmed cell death ligand-1 (PD-L1) and PD-L2. In September 2018, cemiplimab-rwlc became the first systemic therapy approved by the US Food and Drug Administration for the treatment of patients with advanced CSCC ineligible for curative surgery or radiotherapy. In a single-arm Phase II study (NCT02760498), cemiplimab demonstrated substantial antitumor activity, durable responses, and acceptable safety profile in patients with advanced CSCC. The aim of this analysis was to evaluate the cost-effectiveness of cemiplimab in patients with advanced CSCC from a US payer perspective. Methods: A partitioned survival model was developed to assess the cost-effectiveness of cemiplimab versus historical standard of care (SOC). All inputs were identified based on a systematic literature review (SLR), which was supplemented by expert opinion where necessary. The clinical inputs for cemiplimab were based on the individual patient data from the cemiplimab Phase II trial, whereas for SOC, the analysis was based on a pooled analysis of single-arm clinical trials and retrospective studies evaluating chemotherapy and epidermal growth factor receptor inhibitors (cetuximab, erlotinib, and gefitinib) identified via the SLR (6 of the 27 included studies). Overall survival and progression-free survival were extrapolated over a lifetime horizon using parametric functions consistent with guidance from the National Institute for Health and Care Excellence Decision Support Unit. Costs were included for drug acquisition, drug administration, management of adverse events, subsequent therapy, disease management, and terminal care. Unit costs were based on published 2019 US list prices. Results: In the base case, cemiplimab versus SOC resulted in an incremental cost-effectiveness ratio (ICER) of $99,024 per quality adjusted-life year (QALY), where incremental costs and QALYs were $372,425 and 3.76, respectively. At a willingness-to-pay threshold of USD $150,000 per QALY, the probabilistic sensitivity analysis suggests a 91% probability that cemiplimab is cost-effective when compared to SOC. Scenario analyses resulted in ICERs ranging from $90,326 to $147,944. Conclusions: Compared with historical SOC, cemiplimab is a cost-effective use of US payer resources for the treatment of advanced CSCC and is expected to provide value for money.

Critical Appraisal of Published Indirect Comparisons and Network Meta-Analyses of Competing Interventions for Multiple Myeloma

OBJECTIVES

In the field of relapsed or refractory multiple myeloma (RRMM), between-trial or indirect comparisons are required to estimate relative treatment effects between competing interventions based on the available evidence. Two approaches are frequently used in RRMM: network meta-analysis (NMA) and unanchored matching-adjusted indirect comparison (MAIC). The objective of the current study was to evaluate the relevance and credibility of published NMA and unanchored MAIC studies aiming to estimate the comparative efficacy of treatment options for RRMM.

METHODS

Twelve relevant studies were identified in the published literature (n = 7) and from health technology assessment agencies (n = 5). Data from trials were extracted to identify between-trial differences that may have biased results. Credibility of the performed analyses and relevance of the research questions were critically appraised using the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) checklist and feedback based on consultations with clinical experts.

RESULTS

The identified studies concerned NMAs of randomized controlled trials (RCTs; n = 7), unanchored MAICs (n = 4), or both types of analyses (n = 1). According to clinical expert consultation, the majority of the identified NMAs did not consider differences in prior therapies or treatment duration across the RCTs included in the analyses, thereby compromising the relevance.

CONCLUSION

Based on the results and feedback from clinicians, the majority of NMAs did not consider prior treatment history or treatment duration, which resulted in nonrelevant comparisons. Furthermore, it may have compromised the credibility of the estimates owing to differences in effect-modifiers between the different trials. Pairwise comparisons by means of unanchored MAICs require clear justification given the reliance on non-randomized comparisons.

Comparative effectiveness of nivolumab versus clinical practice for advanced gastric or gastroesophageal junction cancer

Aim: To determine the effectiveness of nivolumab compared with routine clinical practice (RCP) for patients with gastric or gastroesophageal cancer refractory to, or intolerant of, two or more previous regimens, using real-world electronic patient records from a US population, a single-arm trial (CheckMate 032) and a randomized controlled trial in an Asian setting (ATTRACTION-2). Materials & methods: A simulated treatment comparison was conducted to predict overall survival for patients treated with nivolumab compared with RCP in the USA. Results: Results of the indirect simulated treatment comparison suggest that nivolumab is associated with a 50% reduction in the risk of all-cause mortality relative to RCP (Hazard ratio: 0.50; 95% CI: 0.36, 0.68). Conclusion: The survival benefit of nivolumab may extend more generally to the USA.

Integrating expert opinion with clinical trial data to extrapolate long-term survival: a case study of CAR-T therapy for children and young adults with relapsed or refractory acute lymphoblastic leukemia

BACKGROUND

Long-term clinical outcomes are necessary to assess the cost-effectiveness of new treatments over a lifetime horizon. Without long-term clinical trial data, current practice to extrapolate survival beyond the trial period involves fitting alternative parametric models to the observed survival. Choosing the most appropriate model is based on how well each model fits to the observed data. Supplementing trial data with feedback from experts may improve the plausibility of survival extrapolations. We demonstrate the feasibility of formally integrating long-term survival estimates from experts with empirical clinical trial data to provide more credible extrapolated survival curves.

METHODS

The case study involved relapsed or refractory B-cell pediatric and young adult acute lymphoblastic leukemia (r/r pALL) regarding long-term survival for tisagenlecleucel (chimeric antigen receptor T-cell [CAR-T]) with evidence from the phase II ELIANA trial. Seven pediatric oncologists and hematologists experienced with CAR-T therapies were recruited. Relevant evidence regarding r/r pALL and tisagenlecleucel provided a common basis for expert judgments. Survival rates and related uncertainty at 2, 3, 4, and 5 years were elicited from experts using a web-based application adapted from Sheffield Elicitation Framework. Estimates from each expert were combined with observed data using time-to-event parametric models that accounted for experts' uncertainty, producing an overall distribution of survival over time. These results were validated based on longer term follow-up (median duration 24.2 months) from ELIANA following the elicitation.

RESULTS

Extrapolated survival curves based on ELIANA trial without expert information were highly uncertain, differing substantially depending on the model choice. Survival estimates between 2 to 5 years from individual experts varied with a fair amount of uncertainty. However, incorporating expert estimates improved the precision in the extrapolated survival curves. Predictions from a Gompertz model, which experts believed was most appropriate, suggested that more than half of the ELIANA patients treated with tisagenlecleucel will survive up to 5 years. Expert estimates at 24 months were validated by longer follow-up.

CONCLUSIONS

This study provides an example of how expert opinion can be elicited and synthesized with observed survival data using a transparent and formal procedure, capturing expert uncertainty, and ensuring projected long-term survival is clinically plausible.

Indirect comparison of nivolumab ± ipilimumab (CheckMate 032) versus other treatments for recurrent small-cell lung cancer

Aim: To estimate the comparative efficacy of nivolumab ± ipilimumab versus alternative treatments for small-cell lung cancer after at least one prior line of chemotherapy. Materials & m ethods: A systematic literature review identified six randomized controlled trials (RCTs) that could be connected in a network. The Kaplan-Meier survival curves from these RCTs were synthesized using network meta-analysis models. Aggregate-level matching was used to connect CheckMate 032 to the RCTs. Results: CheckMate 032 was connected to the network by Amrubicin Clinical Trial-1. Nivolumab ± ipilimumab had a more durable tumor response and more favorable long-term survival versus topotecan via intravenous and versus amrubicin. Conclusion: Compared with chemotherapies for recurrent small-cell lung cancer, nivolumab ± ipilimumab improves response duration, which may translate to long-term survival benefits.

Comparative effectiveness of nivolumab (NIVO) relative to standard of care (SOC) for advanced/metastatic (adv/met) gastric or gastroesophageal junction cancer (GC/GEJC): A simulated treatment comparison (STC)

128

Background: The prognosis of adv/met GC/GEJC among patients receiving third and later lines (L) of therapy is poor, and effective treatment options are limited. The study objective was to estimate the relative effect of NIVO versus SOC for overall survival (OS), in the US among adv/met GC/GEJC patients who received ≥ 3L therapy. Methods: A STC was performed using individual patient data from the single-arm CheckMate 032 (CM032) trial, and the Flatiron Health (FH) database. Eligible patients had adv/met GC/GEJC and received NIVO (CM032) or SOC (FH) as ≥ 3L therapy; all patients met CM032 eligibility criteria. A regression model of OS was fit to CM032 data using prognostic factors and treatment effect modifiers identified through a systematic literature review. The regression model was used to predict OS for NIVO, using Flatiron patient characteristics as covariates, and to estimate the expected outcome if NIVO had been available in the Flatiron population. The observed and predicted OS for NIVO was compared against the observed OS for SOC to generate naïve and adjusted hazard ratio comparisons of NIVO vs SOC. Results: In total, 42 and 43 patients were included from CM032 and Flatiron, respectively. In the Cox model, 19 prognostic factors were considered and the final model adjusted for 6, based on data availability across the two sources: ECOG, alkaline phosphatase (ALP) and hemoglobin, sex, prior surgery, and tumor location. Median OS was 8.97 months in the NIVO group and 5.61 months in the SOC group. The STC adjustment yielded a hazard ratio of 0.66 (95% CI: 0.41 to 1.06) for NIVO vs SOC compared to the naïve estimate of 0.64 (0.40 to 1.03). Sensitivity analyses confirm this result. Conclusions: In the absence of head-to-head data, this study suggests that NIVO may confer a benefit in terms of OS versus SOC for patients with GC/GEJC in ≥ 3L therapy in the US setting. Despite the inherent limitations of using non-randomized comparisons of clinical trial data and real-world evidence, these findings provide insight into the potential benefit of novel agents such as NIVO.

Thirty Years of Evidence on the Efficacy of Drug Treatments for Chronic Heart Failure With Reduced Ejection Fraction: A Network Meta-Analysis

Supplemental Digital Content is available in the text.

Background—

Treatments that reduce mortality and morbidity in patients with heart failure with reduced ejection fraction, including angiotensin-converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARB), β-blockers (BB), mineralocorticoid receptor antagonists (MRA), and angiotensin receptor–neprilysin inhibitors (ARNI), have not been studied in a head-to-head fashion. This network meta-analysis aimed to compare the efficacy of these drugs and their combinations regarding all-cause mortality in patients with heart failure with reduced ejection fraction.

Methods and Results—

A systematic literature review identified 57 randomized controlled trials published between 1987 and 2015, which were compared in terms of study and patient characteristics, baseline risk, outcome definitions, and the observed treatment effects. Despite differences identified in terms of study duration, New York Heart Association class, ejection fraction, and use of background digoxin, a network meta-analysis was considered feasible and all trials were analyzed simultaneously. The random-effects network meta-analysis suggested that the combination of ACEI+BB+MRA was associated with a 56% reduction in mortality versus placebo (hazard ratio 0.44, 95% credible interval 0.26–0.66); ARNI+BB+MRA was associated with the greatest reduction in all-cause mortality versus placebo (hazard ratio 0.37, 95% credible interval 0.19–0.65). A sensitivity analysis that did not account for background therapy suggested that ARNI monotherapy is more efficacious than ACEI or ARB monotherapy.

Conclusions—

The network meta-analysis showed that treatment with ACEI, ARB, BB, MRA, and ARNI and their combinations were better than the treatment with placebo in reducing all-cause mortality, with the exception of ARB monotherapy and ARB plus ACEI. The combination of ARNI+BB+MRA resulted in the greatest mortality reduction.

Improving physical and mental health in frontline mental health care providers: Yoga-based stress management versus cognitive behavioral stress management

The need for brief, low-cost, easily disseminable and effective interventions to promote healthy lifestyles is high. This is especially true for mental health providers. We developed two studies to compare the impacts of Cognitive Behavioral Stress Management (CBSM) and Yoga Based Stress Management (YBSM) interventions for healthcare professionals. Study 1 offered an 8-week YBSM intervention to 37 mental healthcare participants and collected health data pre and post. Study 2 offered YBSM and CBSM classes to 40 randomly assigned mental healthcare providers and collected mental and physical health data at four time points. In Study 1, using t-tests, the YBSM intervention affected a number of mental and physical wellbeing indices pre to post. In Study 2, using linear mixed modeling, both YBSM and CBSM groups improved significantly (p <.05) in fruit and vegetable intake, heart rate, alcohol consumption, relaxation and awareness, professional quality of life, compassion satisfaction, burnout, depression, and stress levels. There was a group by time effect for coping confidence (CBSM increased more, p<.05, F = 4.34), physical activity (YBSM increased more, p<.05, F = 3.47), overall mental health (YBSM increased more, p<.10, F =5.32), and secondary traumatic stress (YBSM decreased more, p<.10, F = 4.89). YBSM and CBSM appear to be useful for healthcare professionals' mental and physical health. YBSM demonstrates some benefit above and beyond the extremely well-studied and empirically supported CBSM, including increased physical activity, overall mental health, and decreased secondary traumatic stress benefits.

Network meta-analysis of longitudinal data using fractional polynomials

Network meta-analysis of randomized controlled trials (RCTs) are often based on one treatment effect measure per study. However, many studies report data at multiple time points. Furthermore, not all studies measure the outcomes at the same time points. As an alternative to a network meta-analysis based on a synthesis of the results at one time point, a network meta-analysis method is presented that allows for the simultaneous analysis of outcomes at multiple time points. The development of outcomes over time of interventions compared in an RCT is modeled with fractional polynomials, and the differences between the parameters of these polynomials within a trial are synthesized across studies with a Bayesian network meta-analysis. The proposed models are illustrated with an analysis of RCTs evaluating interventions for osteoarthritis of the knee. Fixed and random effects second order fractional polynomials were applied to the case study. Network meta-analysis with models that represent the treatment effects in terms of several parameters using fractional polynomials can be considered a useful addition to models for network meta-analysis of repeated measures previously proposed. When RCTs report treatment effects at multiple follow-up times, these models can be used to synthesize the results even if reporting times differ across the studies.

Critical appraisal of network meta-analyses evaluating the efficacy and safety of new oral anticoagulants in atrial fibrillation stroke prevention trials

OBJECTIVES

To critically appraise published network meta-analyses (NMAs) evaluating the efficacy or safety of the new oral anticogulants (NOACs) dabigatran, rivaroxaban, and apixaban for the prevention of stroke in patients with nonvalvular atrial fibrillation (AF).

METHODS

A systematic literature review was performed to identify the relevant NMAs using MEDLINE, EMBASE, Cochrane Library, Database of Abstracts of Reviews of Effects, and Health Technology Assessment. The synthesis studies were evaluated using the "Questionnaire to assess the relevance and credibility of the NMA."

RESULTS

Eleven NMAs evaluating NOACs among adults with nonvalvular AF were identified. Most NMAs included three large phase III randomized controlled trials, comparing NOACs to adjusted-dose warfarin (Randomized Evaluation of Long-Term Anticoagulation Therapy [RE-LY], Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation [ROCKET-AF], and Apixaban for Reduction of Stroke and Other Thromboembolic Events in Atrial Fibrillation [ARISTOTLE]). The main differences identified related to potential treatment effect modifiers regarding the mean time spent in therapeutic range (TTR) in the warfarin arm, the risk of stroke or systemic embolism across the trials (mean CHADS2 score: C = congestive heart failure, H = hypertension, A = older than age 75 years, D = diabetes mellitus, S2 = prior stroke or history of transient ischemic attack) or primary versus secondary prevention, and type of populations used in the analysis. Kansal et al. [Kansal AR, Sharma M, Bradley-Kennedy C, et al. Dabigatran versus rivaroxaban for the prevention of stroke and systemic embolism in atrial fibrillation in Canada: comparative efficacy and cost-effectiveness. Thromb Haemost 2012;108:672-82] appropriately adjusted the ROCKET-AF TTR to match the RE-LY population on the basis of individual patient data. Meta-regressions are not expected to minimize confounding bias given limited data, whereas subgroup analyses had some impact on the point estimates for the treatment comparisons.

CONCLUSIONS

Results of the synthesis studies were generally comparable and suggested that the NOACs had similar efficacy, although some differences were identified depending on the outcome. The extent to which differences in the distribution of TTR, CHADS2 score, or primary versus secondary prevention biased the results remains unclear.

A process for assessing the feasibility of a network meta-analysis: a case study of everolimus in combination with hormonal therapy versus chemotherapy for advanced breast cancer

BACKGROUND

The aim of this study is to outline a general process for assessing the feasibility of performing a valid network meta-analysis (NMA) of randomized controlled trials (RCTs) to synthesize direct and indirect evidence for alternative treatments for a specific disease population.

METHODS

Several steps to assess the feasibility of an NMA are proposed based on existing recommendations. Next, a case study is used to illustrate this NMA feasibility assessment process in order to compare everolimus in combination with hormonal therapy to alternative chemotherapies in terms of progression-free survival for women with advanced breast cancer.

RESULTS

A general process for assessing the feasibility of an NMA is outlined that incorporates explicit steps to visualize the heterogeneity in terms of treatment and outcome characteristics (Part A) as well as the study and patient characteristics (Part B). Additionally, steps are performed to illustrate differences within and across different types of direct comparisons in terms of baseline risk (Part C) and observed treatment effects (Part D) since there is a risk that the treatment effect modifiers identified may not explain the observed heterogeneity or inconsistency in the results due to unexpected, unreported or unmeasured differences. Depending on the data available, alternative approaches are suggested: list assumptions, perform a meta-regression analysis, subgroup analysis, sensitivity analyses, or summarize why an NMA is not feasible.

CONCLUSIONS

The process outlined to assess the feasibility of an NMA provides a stepwise framework that will help to ensure that the underlying assumptions are systematically explored and that the risks (and benefits) of pooling and indirectly comparing treatment effects from RCTs for a particular research question are transparent.

Quantitative summaries of treatment effect estimates obtained with network meta-analysis of survival curves to inform decision-making

BACKGROUND

Increasingly, network meta-analysis (NMA) of published survival data are based on parametric survival curves as opposed to reported hazard ratios to avoid relying on the proportional hazards assumption. If a Bayesian framework is used for the NMA, rank probabilities associated with the alternative treatments can be obtained, which directly support decision-making. In the context of survival analysis multiple treatment effect measures are available to inform the rank probabilities.

METHODS

A fractional polynomial NMA of overall survival in advanced melanoma was performed as an illustrative example. Rank probabilities were calculated and presented for the following effect measures: 1) median survival; 2) expected survival; 3) mean survival at the follow-up time point of the trial with the shortest follow-up; 4) hazard or hazard ratio over time; 5) cumulative hazard or survival proportions over time; and 6) mean survival at subsequent time points. The advantages and disadvantages of the alternative measures were discussed.

RESULTS

Since hazard and survival estimates may vary over time for the compared interventions, calculations of rank probabilities for an NMA of survival curves may depend on the effect measure. With methods 1-3 rank probabilities do not vary over time, which are easier to understand and communicate than rank probabilities that vary over time as obtained with methods 4-6. However, rank probabilities based on methods 4-6 provide useful information regarding the relative treatment effects over time.

CONCLUSIONS

Different approaches to summarize results of a NMA of survival curves with rank probabilities have pros and cons. Rank probabilities of treatment effects over time provide a more transparent and informative approach to help guide decision-making than single rank probabilities based on collapsed measures, such as median survival or expected survival. Rank probabilities based on survival proportions are the most intuitive and straightforward to communicate, but alternatives based on the hazard function or mean survival over time may also be useful.

Comparative efficacy of long-acting bronchodilators for COPD: a network meta-analysis

BACKGROUND

Clinicians are faced with an increasingly difficult choice regarding the optimal bronchodilator for patients with chronic obstructive pulmonary disease (COPD) given the number of new treatments. The objective of this study is to evaluate the comparative efficacy of indacaterol 75/150/300 μg once daily (OD), glycopyrronium bromide 50 μg OD, tiotropium bromide 18 μg/5 μg OD, salmeterol 50 μg twice daily (BID), formoterol 12 μg BID, and placebo for moderate to severe COPD.

METHODS

Forty randomized controlled trials were combined in a Bayesian network meta-analysis. Outcomes of interest were trough and post-dose forced expiratory volume in 1 second (FEV1), St. George's Respiratory Questionnaire (SGRQ) score and responders (≥4 points), and Transition Dyspnea Index (TDI) score and responders (≥1 point) at 6 months.

RESULTS

Indacaterol was associated with a higher trough FEV1 than other active treatments (difference for indacaterol 150 μg and 300 μg versus placebo: 152 mL (95% credible interval (CrI): 126, 179); 160 mL (95% CrI: 133, 187)) and the greatest improvement in SGRQ score (difference for indacaterol 150 μg and 300 μg versus placebo: -3.9 (95% CrI -5.2, -2.6); -3.6 (95% CrI -4.8, -2.3)). Glycopyrronium and tiotropium 18 μg resulted in the next best estimates for both outcomes with minor differences (difference for glycopyrronium versus tiotropium for trough FEV1 and SGRQ: 18 mL (95% CrI: -16, 51); -0.55 (95% CrI: -2.04, 0.92).

CONCLUSION

In terms of trough FEV1 and SGRQ score indacaterol, glycopyrronium, and tiotropium are expected to be the most effective bronchodilators.

Progression-free survival with fulvestrant 500 mg and alternative endocrine therapies as second-line treatment for advanced breast cancer: a network meta-analysis with parametric survival models

BACKGROUND

Ouwens et al. and Jansen have presented methods for (network) meta-analysis of survival data by using a multidimensional treatment effect as an alternative to the synthesis of constant hazards ratios, which allow for a better fit to the data and the expected survival of competing interventions for cost-effectiveness analysis. However, results may be sensitive to the assumed underlying survival function.

OBJECTIVE

To estimate the expected progression-free survival (PFS) for fulvestrant 500 mg versus alternative hormonal therapies for postmenopausal women with advanced breast cancer who relapsed previously by means of a network meta-analysis of currently available randomized controlled trials using alternative underlying survival functions.

METHODS

Eleven randomized controlled trials were included that evaluated fulvestrant 500 mg (n = 3), fulvestrant 250 mg (n = 5), fulvestrant 250 mg loading dose (n = 3), anastrozole 1 mg (n = 3), megestrol acetate (n = 4), letrozole 2.5 mg (n = 3), letrozole 0.5 mg (n = 3), and exemestane (n = 2). PFS percentages and numbers at risk were derived from Kaplan-Meier curves and combined by means of Bayesian network meta-analysis on the basis of the difference in the shape and scale parameters of the Weibull, log-normal, and log-logistic parametric survival functions.

RESULTS

The log-normal distribution provided the best fit, suggesting that the proportional hazard assumption was not valid. Based on the difference in expected PFS, it was found that fulvestrant 500 mg is more efficacious than fulvestrant 250 mg, megestrol acetate, and anastrozole (-5.73 months; 95% credible interval [CrI]-10.67,-1.67). Expected PFS for fulvestrant 500 mg ranged from 10.87 (95% CrI 9.21, 13.07) to 17.02 (95% CrI 13.33, 22.02) months for the Weibull versus log-logistic distribution.

CONCLUSIONS

Fulvestrant 500 mg is expected to be more efficacious than fulvestrant 250 mg, megestrol acetate, and anastrozole 1 mg and at least as efficacious as exemestane and letrozole 2.5 mg in terms of PFS among postmenopausal women with advanced breast cancer after failure on endocrine therapy. The findings were not sensitive to the distribution, although the expected PFS varied substantially, emphasizing the importance of performing sensitivity analyses.

Meta-regression models to address heterogeneity and inconsistency in network meta-analysis of survival outcomes

BACKGROUND

Recently, network meta-analysis of survival data with a multidimensional treatment effect was introduced. With these models the hazard ratio is not assumed to be constant over time, thereby reducing the possibility of violating transitivity in indirect comparisons. However, bias is still present if there are systematic differences in treatment effect modifiers across comparisons.

METHODS

In this paper we present multidimensional network meta-analysis models for time-to-event data that are extended with covariates to explain heterogeneity and adjust for confounding bias in the synthesis of evidence networks of randomized controlled trials. The impact of a covariate on the treatment effect can be assumed to be treatment specific or constant for all treatments compared.

RESULTS

An illustrative example analysis is presented for a network of randomized controlled trials evaluating different interventions for advanced melanoma. Incorporating a covariate related to the study date resulted in different estimates for the hazard ratios over time than an analysis without this covariate, indicating the importance of adjusting for changes in contextual factors over time.

CONCLUSION

Adding treatment-by-covariate interactions to multidimensional network meta-analysis models for published survival curves can be worthwhile to explain systematic differences across comparisons, thereby reducing inconsistencies and bias. An additional advantage is that heterogeneity in treatment effects can be explored.

Gabapentin in the treatment of post-dural puncture headache: a case series

Gabapentin has been reported to be useful in the management of epilepsy, neuropathic pain and post-dural puncture headache. Seventeen obstetric cases are presented in which gabapentin was used either as a primary therapy for the management of severe headache following a diagnosed dural puncture or as an analgesic adjunct in patients with dural puncture headache unresponsive to epidural blood patch. In our patients, analgesic therapy was essential to enable care of their newborns as other management options had failed or were unavailable. In nine patients we observed an excellent result with reduction of headache severity within 24 hours. Gabapentin appears potentially beneficial in the management of patients with post-dural puncture headaches.

Efficacy of indacaterol 75 μg versus fixed-dose combinations of formoterol-budesonide or salmeterol-fluticasone for COPD: a network meta-analysis

Background

The purpose of this study was to update our network meta-analysis in order to compare the efficacy of indacaterol 75 μg with that of a fixed-dose combination of formoterol and budesonide (FOR/BUD) and a fixed-dose combination salmeterol and fluticasone (SAL/FP) for the treatment of chronic obstructive pulmonary disease (COPD) based on evidence identified previously in addition to two new randomized clinical trials.

Methods

Fifteen randomized, placebo-controlled clinical trials including COPD patients were evaluated: indacaterol 75 μg once daily (n = 2 studies), indacaterol 150 μg once daily (n = 5), indacaterol 300 μg once daily (n = 4), FOR/BUD 9/160 μg twice daily (n = 2), FOR/BUD 9/320 μg twice daily (n = 2), SAL/FP 50/500 μg twice daily (n = 4), and SAL/FP 50/250 μg twice daily (n = 1). All trials were analyzed simultaneously using a Bayesian network meta-analysis and relative treatment effects between all regimens were obtained. Treatment-by-covariate interactions were included where possible to improve the similarity of the trials. Outcomes of interest were trough forced expiratory volume in 1 second (FEV₁) and transitional dyspnea index at 12 weeks.

Results

Based on the results without adjustment for covariates, indacaterol 75 μg resulted in a greater improvement in FEV₁ at 12 weeks compared with FOR/BUD 9/160 μg (difference in change from baseline 0.09 L [95% credible interval 0.04–0.13]) and FOR/BUD 9/320 μg (0.07 L [0.03–0.11]) and was comparable with SAL/FP 50/250 μg (0.00 L [−0.07–0.07]) and SAL/FP 50/500 μg (0.01 L [−0.04–0.05]). For transitional dyspnea index, data was available only for indacaterol 75 μg versus SAL/FP 50/500 μg (−0.49 points [−1.87–0.89]).

Conclusion

Based on results of a network meta-analysis with and without covariates, indacaterol 75 μg is expected to be at least as efficacious as FOR/BUD (9/320 μg and 9/160 μg) and comparable with SAL/FP (50/250 μg and 50/500 μg) in terms of lung function. In terms of breathlessness (transitional dyspnea index) at 12 weeks, the results are inconclusive given the limited data.

Efficacy of once-daily indacaterol 75 μg relative to alternative bronchodilators in COPD: a study level and a patient level network meta-analysis

BACKGROUND

The objective of this study was to evaluate the comparative efficacy of indacaterol 75 μg once daily (OD), tiotropium 18 μg OD, salmeterol 50 μg twice daily (BID), formoterol 12 μg BID, and placebo for the treatment of chronic obstructive pulmonary disease (COPD) based on individual patient data (IPD) from randomized controlled trials (RCTs) from the indacaterol trial program and aggregate data (AD) identified from a systematic review of RCTs.

METHODS

22 RCTs were included in the AD analysis that evaluated: indacaterol 75 μg (n = 2 studies), indacaterol 150 μg n = 5 (i.e. salmeterol 50 μg) (n = 5), indacaterol 300 μg (n = 2), tiotropium 18 μg (n = 10), salmeterol 50 μg (n = 7), and formoterol 12 μg (n = 4). All of the studies except for one head-to-head comparison (tiotropium vs. salmeterol) were placebo controlled. Outcomes of interest were trough forced expiratory volume in 1 second (FEV1) and St. George's Respiratory Questionnaire (SGRQ) total score at week 12. The AD from all trials was analysed simultaneously using a Bayesian network meta-analysis (NMA) and relative treatment effects between all regimens were obtained. In a separate analysis, the IPD available from the 6 indacaterol RCTs was analysed in a NMA. Treatment-by-covariate interactions were included in both analyses to improve similarity of the trials.

RESULTS

All interventions compared were more efficacious than placebo regarding FEV1 at 12 weeks. Indacaterol 75 μg is expected to result in a comparable FEV1 at 12 weeks to tiotropium and salmeterol based on both IPD and AD analyses. In comparison to formoterol, the IPD and AD results indicate indacaterol 75 μg is more efficacious (IPD = 0.07 L difference; 95%Credible Interval (CrI) 0.02 to 0.11; AD = 0.05 L difference; 95%CrI 0.01; 0.09). In terms of SGRQ total score at 12 weeks, indacaterol 75 μg and formoterol were more efficacious than placebo, whereas for tiotropium and salmeterol the credible intervals included zero for the AD results only (tiotropium: -2.99 points improvement versus placebo; 95%CrI -6.48 to 0.43; salmeterol:-2.52; 95%CrI: -5.34; 0.44). Both IPD and AD results suggest that indacaterol 75 μg is expected to be comparable to all active treatments.

CONCLUSIONS

Based on a synthesis of currently available AD RCT evidence as well as an IPD network meta-analysis of six RCTs, indacaterol 75 μg is expected to be at least as efficacious as formoterol and comparable to tiotropium and salmeterol regarding FEV1. Furthermore, indacaterol 75 μg shows comparable level of improvement in health-related quality of life to tiotropium, salmeterol, and formoterol, as measured by the SGRQ.

Efficacy of once-daily indacaterol relative to alternative bronchodilators in COPD: a patient-level mixed treatment comparison

OBJECTIVE

Indacaterol was evaluated versus placebo, formoterol, and salmeterol in randomized controlled trials. No direct comparisons, however, are available for indacaterol 150 μg with formoterol or indacaterol 300 μg with salmeterol. Indacaterol trial evidence was synthesized to provide coherent estimates of indacaterol 150 μg and indacaterol 300 μg relative to formoterol, salmeterol, and tiotropium.

METHODS

Four randomized controlled trials were combined with Bayesian mixed treatment comparisons by using individual patient-level data. End points of interest were trough forced expiratory volume in 1 second (FEV(1)), St. George's Respiratory Questionnaire (SGRQ) total score and response (≥ 4 points), and Transition Dyspnea Index total score and response (≥ 1 point).

RESULTS

Indacaterol 150 μg demonstrated a higher FEV(1) than did formoterol at 12 weeks and 6 months (0.10 L difference; 95% credible interval [CrI] = 0.06-0.14), as did indacaterol 300 μg versus salmeterol (0.06 L difference at 12 weeks; CrI = 0.02-0.10; 0.06 L at 6 months; CrI = 0.02-0.11). Regarding SGRQ, indacaterol 150 μg demonstrated a comparable proportion of responders versus formoterol, as did indacaterol 300 μg versus salmeterol. In comparison to tiotropium, indacaterol 150 μg demonstrated a greater proportion of responders (odds ratio = 1.52 at 12 weeks; CrI 1.15-2.00). For Transition Dyspnea Index, indacaterol 150 μg and formoterol showed a similar response. Indacaterol 300 μg was more efficacious than salmeterol (odds ratio = 1.65 at 12 weeks; CrI 1.16-2.34). Overall, indacaterol 150 μg showed the greatest efficacy for SGRQ and indacaterol 300 μg for FEV(1) and Transition Dyspnea Index.

CONCLUSION

Indacaterol is expected to be comparable to formoterol, salmeterol, and tiotropium, providing higher FEV(1) than formoterol and salmeterol and greater improvement in the SGRQ total score than tiotropium. Indacaterol 150 μg provided comparable improvement in dyspnea, while indacaterol 300 μg demonstrated the greatest response overall.

Comparative efficacy of indacaterol 150 μg and 300 μg versus fixed-dose combinations of formoterol + budesonide or salmeterol + fluticasone for the treatment of chronic obstructive pulmonary disease--a network meta-analysis

Objective:

To compare efficacy of indacaterol to that of fixed-dose combination (FDC) formoterol and budesonide (FOR/BUD) and FDC salmeterol and fluticasone (SAL/FP) for the treatment of chronic obstructive pulmonary disease (COPD) based on the available randomized clinical trials (RCTs).

Methods:

Fifteen placebo-controlled RCTs were included that evaluated: indacaterol 150 μg (n = 5 studies), indacaterol 300 μg (n = 4), FOR/BUD 9/160 μg (n = 2), FOR/BUD 9/320 μg (n = 3), SAL/FP 50/500 μg (n = 5), and SAL/FP 50/250 μg (n = 1). Outcomes of interest were trough forced expiratory volume in 1 second (FEV₁), total scores for St. George’s Respiratory Questionnaire (SGRQ), and transition dyspnea index (TDI). All trials were analyzed simultaneously using a Bayesian network meta-analysis and relative treatment effects between all regimens were obtained. Treatment-by-covariate interactions were included where possible to improve the similarity of the trials.

Results:

Indacaterol 150 μg resulted in a higher change from baseline (CFB) in FEV₁ at 12 weeks compared to FOR/BUD 9/160 μg (difference in CFB 0.11 L [95% credible intervals: 0.08, 0.13]) and FOR/BUD 9/320 μg (0.09 L [0.06, 0.11]) and was comparable to SAL/FP 50/250 μg (0.02 L [−0.04, 0.08]) and SAL/FP 50/500 μg (0.03 L [0.00, 0.06]). Similar results were observed for indacaterol 300 μg at 12 weeks and indacaterol 150/300 μg at 6 months. Indacaterol 150 μg demonstrated comparable improvement in SGRQ total score at 6 months versus FOR/BUD (both doses), and SAL/FP 50/500 μg (−2.16 point improvement [−4.96, 0.95]). Indacaterol 150 and 300 μg demonstrated comparable TDI scores versus SAL/FP 50/250 μg (0.21 points (−0.57, 0.99); 0.39 [−0.39, 1.17], respectively) and SAL/FP 50/500 μg at 6 months.

Conclusion:

Indacaterol monotherapy is expected to be at least as good as FOR/BUD (9/320 and 9/160 μg) and comparable to SAL/FP (50/250 and 50/500 μg) in terms of lung function. Indacaterol is also expected to be comparable to FOR/BUD (9/320 and 9/160 μg) and SAL/FP 50/500 μg in terms of health status and to SAL/FP (50/250 and 50/500 μg) in terms of breathlessness.

Evaluation of novel particles as an inhalation system for GLP-1

AIM

The feasibility of administering native glucagon-like peptide 1 (GLP-1) as GLP-1 Technosphere Inhalation Powder for diabetes therapy has been demonstrated in a rat model.

METHODS

GLP-1 Technosphere Inhalation Powders containing 5, 10 and 15% GLP-1 were prepared and administered to healthy female Sprague-Dawley rats and to male Zucker diabetic obese rats. Rats received a single dose of GLP-1 Technosphere Powder by pulmonary insufflation. GLP-1 pharmacokinetic and pharmacodynamic responses were measured.

RESULTS

Maximum circulating GLP-1 concentrations were achieved at approximately 10 min after dosing with detectable levels at 40 min. In a food consumption study, Sprague-Dawley rats receiving GLP-1 Technosphere Powder once-daily consumed less food than control rats for up to 24 h after dosing. Cumulative food consumption was decreased approximately 10% after 78 h. In an intraperitoneal glucose tolerance test, Zucker diabetic fatty rats receiving 2 mg GLP-1 Technosphere Powder (0.3 mg GLP-1) by pulmonary insufflation exhibited lower glucose concentrations and higher insulin concentrations than control rats. Pancreatic evaluations showed no differences in apoptotic index or cell proliferation of beta-cells. In addition, a dose-related increase in insulin expression within the pancreas was observed.

CONCLUSIONS

These data demonstrate the feasibility of administering native GLP-1 as GLP-1 Technosphere Inhalation Powder for diabetes therapy.