Replication of randomized clinical trial results using real-world data: paving the way for effectiveness decisions

Comparing Survival Outcomes between Hemodialysis and Hemodiafiltration Using Real-World Data from Brazil

The CONVINCE trial demonstrates that high-dose hemodiafiltration offers a survival advantage for patients in the high-flux hemodiafiltration group compared to hemodialysis. We compared the outcomes of hemodialysis and hemodiafiltration using real-world data. We conducted an analysis on a cohort of patients who underwent hemodiafiltration therapy (HDF) at a single center, NefroStar Clinics. The results obtained were then compared with data from patients receiving hemodialysis (HD) therapy within the Brazilian Public Health System (SUS). The primary outcome was mortality from any cause. Results: A total of 85 patients undergoing hemodiafiltration were compared with 149,372 patients receiving hemodialysis through the Brazilian Public Health System (SUS). Using a 2:1 propensity score, we compared the 170 best-match HD patients with 85 HDF patients. In the Cox analysis, HDF therapy showed a reduced risk of mortality with an HR of 0.29 [0.11-0.77]. The propensity score analysis showed a HR of 0.32 [95% CI: 0.11-0.91]. This analysis was adjusted for age, type of access, KT/v, hemoglobin, and phosphorus. The Kaplan-Meier analysis showed respective survival rates for HDF and HD at the end of one year, 92.1% and 79.9%, p < 0.001. These results suggest high-flux hemodiafiltration has survival advantages over hemodialysis in a real-world scenario.

Real-World Progression-Free Survival as an Endpoint in Lung Cancer: Replicating Atezolizumab and Docetaxel Arms of the OAK Trial Using Real-World Data

Evaluating cancer treatments in real-world data (RWD) requires informative endpoints. This study replicated the atezolizumab and docetaxel arms of the OAK trial using RWD and compared progression-free survival (PFS) outcomes derived from abstracted physician's notes in RWD (rwPFS) against PFS outcomes derived from the clinical trial PFS (ctPFS). Atezolizumab and docetaxel arms of the phase III OAK randomized controlled trial (RCT; NCT02008227) were replicated in a US nationwide real-world database using selected OAK inclusion/exclusion criteria and propensity score-based adjustment for baseline prognostic variables. Concordance of outcomes was assessed using Kaplan-Meier medians and hazard ratios (HRs). The RWD cohorts comprised 133 patients on atezolizumab and 479 patients on docetaxel. After adjustment, prognostic variables were balanced between RCT arms and corresponding RWD cohorts. The rwPFS and ctPFS outcomes showed better concordance for docetaxel (2.99 vs. 3.52 months; HR: 0.99, 95% confidence interval (CI): 0.85-1.15) than for atezolizumab (3.71 vs. 2.76 months; HR: 0.8, 95% CI: 0.61-1.02). Excluding events labeled "pseudo-progression" from both RWD and RCT improved concordance for atezolizumab (4.24 vs. 4.14 months; HR: 0.95, 95% CI: 0.70-1.25). These findings were robust across sensitivity analyses. Replicating RCTs using RWD and comparing outcomes can help characterize RWD endpoints. Similarity of results between rwPFS and ctPFS at the cohort level may depend on drug category, highlighting the need for further studies to verify and understand when the corresponding outcomes can be compared, including within the same patient.

Real-world patient characteristics, treatment patterns, and clinical outcomes associated with tucatinib therapy in HER2-positive metastatic breast cancer

Background

Tucatinib is an oral human epidermal growth factor receptor 2 (HER2)-directed therapy approved in combination with trastuzumab and capecitabine for use in patients with previously treated HER2+ metastatic breast cancer (MBC) with/without brain metastases (BM). To inform clinical decision-making, it is important to understand tucatinib use in real-world clinical practice. We describe patient characteristics, treatment patterns, and clinical outcomes for tucatinib treatment in the real-world setting.

Methods

This retrospective cohort study included patients diagnosed with HER2+ MBC (January 2017-December 2022) who received tucatinib treatment in a nationwide, de-identified electronic health record-derived metastatic breast cancer database. Patient demographics and clinical characteristics were described at baseline (prior to tucatinib initiation). Key outcomes included real-world time to treatment discontinuation (rwTTD), time to next treatment (rwTTNT), and overall survival (rwOS).

Results

Of 3,449 patients with HER2+ MBC, 216 received tucatinib treatment (n=153 with BM; n=63 without BM) and met inclusion criteria. Median (range) age of patients was 56 (28-84) years, 57.9% were White, and 68.5% had Eastern Cooperative Oncology Group performance status ≤1. Median (IQR) follow-up from start of tucatinib treatment was 12 (6-18) months. Among all patients who received tucatinib treatment, median (95% CI) rwTTD was 6.5 (5.4-8.8) months with 39.8% and 21.4% remaining on treatment at 12 and 24 months, respectively. Median (95% CI) rwTTNT was 8.7 (6.8-10.7) months. Patients who received the approved tucatinib triplet combination after ≥1 HER2-directed regimen in the metastatic setting had a similar median (95% CI) rwTTD (any line: 8.1 [5.7-9.5] months; second-line (2L) and third-line (3L): 9.4 [6.3-14.1] months) and rwTTNT (any line: 8.8 [7.1-11.8] months; 2L and 3L: 9.8 [6.8-14.1] months) to the overall population. Overall, median (95% CI) rwOS was 26.6 (20.2-not reached [NR]) months, with similar findings for patients who received the tucatinib triplet (26.1 [18.8-NR] months) and was NR in the subgroup limited to the 2L/3L population.

Conclusion

Tucatinib treatment in the real-world setting was associated with a similar median rwTTD, rwTTNT, and rwOS as in the pivotal HER2CLIMB trial, with particular effectiveness in patients in the 2L/3L setting. These results highlight the importance of earlier use of tucatinib in HER2+ MBC.

Biosimilars versus the originator of follitropin alfa: Randomized controlled trials are still the best way to evaluate their comparative effectiveness in assisted reproduction

Biosimilars of follitropin alfa have been introduced in many countries as more affordable alternatives to the reference product for patients undergoing ovarian stimulation for assisted reproductive technology cycles. A recent meta-analysis, by reviewing available evidence originating from randomised controlled trials, has shown that based on the best available evidence, biosimilars of follitropin alfa are associated with lower live birth, ongoing and clinical pregnancy rates compared to the reference product. A subsequently published opinion paper challenges the methodology and results of this meta-analysis and suggests that these data should be ignored. In the present paper, it is clearly demonstrated why this criticism is largely unfounded and in stark contradiction with basic principles of evidence-based medicine. Furthermore, it is presented why the results of this meta-analysis provide the best available evidence to date and therefore the base that should inform clinical practice and, importantly, stimulate further research.

An Attempt to Replicate Randomized Trials of Diabetes Treatments Using a Japanese Administrative Claims and Health Checkup Database: A Feasibility Study

BACKGROUND

Use of real-world evidence (RWE) has been limited for evaluating effectiveness because of the lack of confidence in its reliability. Examining whether a rigorously designed observational study using real-world data (RWD) can reproduce the results of a randomized controlled trial (RCT) will provide insights into the implementation of high-quality RWE studies that can produce valid conclusions.

OBJECTIVE

We aimed to replicate published RCTs using a Japanese claims and health checkup database and examine whether the emulated RWE studies' results agree with those of the original RCTs.

METHODS

We selected three RCTs on diabetes medications for replication in patients with type 2 diabetes. The study outcome was either the change or percentage change in HbA1c levels from baseline. We designed three observational studies using the RWD to mimic the critical study elements of the respective RCTs as closely as possible. We performed 1:1 propensity score nearest-neighbor matching to balance the groups for potential confounders. The differences in outcomes between the groups and their 95% confidence intervals (CIs) were calculated in each RWE study, and the results were compared with those of the RCT.

RESULTS

Patient characteristics, such as age, sex, and duration of diabetes, differed between the RWE studies and RCTs. In Trial 1 emulation, the percentage changes in HbA1c levels were larger in the treatment group than in the comparator group (difference -6.21, 95% confidence interval (CI) -11.01 to -1.40). In Trial 2, the change in HbA1c level was larger in the treatment group (difference -0.01; 95% CI -0.25 to 0.23), and in Trial 3, it was smaller in the treatment group (difference 0.46; 95% CI -0.01 to 0.94). These results did not show regulatory or estimate agreement with the RCTs.

CONCLUSIONS

None of the three emulated RWE studies using this claims and health checkup database reproduced the same conclusions as the RCTs. These discrepancies could largely be attributed to design differences between RWE studies and RCTs, primarily due to the lack of necessary data in the database. This particular RWD source may not be the best fit for evaluating treatment effects using laboratory data as the study outcome.

Causal analyses with target trial emulation for real-world evidence removed large self-inflicted biases: systematic bias assessment of ovarian cancer treatment effectiveness

BACKGROUND AND OBJECTIVES

Drawing causal conclusions from real-world data (RWD) poses methodological challenges and risk of bias. We aimed to systematically assess the type and impact of potential biases that may occur when analyzing RWD using the case of progressive ovarian cancer.

METHODS

We retrospectively compared overall survival with and without second-line chemotherapy (LOT2) using electronic medical records. Potential biases were determined using directed acyclic graphs. We followed a stepwise analytic approach ranging from crude analysis and multivariable-adjusted Cox model up to a full causal analysis using a marginal structural Cox model with replicates emulating a reference randomized controlled trial (RCT). To assess biases, we compared effect estimates (hazard ratios [HRs]) of each approach to the HR of the reference trial.

RESULTS

The reference trial showed an HR for second line vs. delayed therapy of 1.01 (95% confidence interval [95% CI]: 0.82-1.25). The corresponding HRs from the RWD analysis ranged from 0.51 for simple baseline adjustments to 1.41 (95% CI: 1.22-1.64) accounting for immortal time bias with time-varying covariates. Causal trial emulation yielded an HR of 1.12 (95% CI: 0.96-1.28).

CONCLUSION

Our study, using ovarian cancer as an example, shows the importance of a thorough causal design and analysis if one is expecting RWD to emulate clinical trial results.

A pragmatic effectiveness-implementation study comparing trial evidence with routinely collected outcome data for patients receiving the REACH-HF home-based cardiac rehabilitation programme

BACKGROUND

Cardiac rehabilitation for heart failure continues to be greatly underused worldwide despite being a Class I recommendation in international clinical guidelines and uptake is low in women and patients with mental health comorbidities.

METHODS

Rehabilitation EnAblement in CHronic Heart Failure (REACH-HF) programme was implemented in four UK National Health Service early adopter sites ('Beacon Sites') between June 2019 and June 2020. Implementation and patient-reported outcome data were collected across sites as part of the National Audit of Cardiac Rehabilitation. The change in key outcomes before and after the supervised period of REACH-HF intervention across the Beacon Sites was assessed and compared to those of the intervention arm of the REACH-HF multicentre trial.

RESULTS

Compared to the REACH-HF multicentre trial, patients treated at the Beacon Site were more likely to be female (33.8% vs 22.9%), older (75.6 vs 70.1), had a more severe classification of heart failure (26.5% vs 17.7%), had poorer baseline health-related quality of life (MLHFQ score 36.1 vs 31.4), were more depressed (HADS score 6.4 vs 4.1) and anxious (HADS score 7.2 vs 4.7), and had lower exercise capacity (ISWT distance 190 m vs 274.7 m). There appeared to be a substantial heterogeneity in the implementation process across the four Beacon Sites as evidenced by the variation in levels of patient recruitment, operationalisation of the REACH-HF intervention and patient outcomes. Overall lower improvements in patient-reported outcomes at the Beacon Sites compared to the trial may reflect differences in the population studied (having higher morbidity at baseline) as well as the marked challenges in intervention delivery during the COVID-19 pandemic.

CONCLUSION

The results of this study illustrate the challenges in consistently implementing an intervention (shown to be clinically effective and cost-effective in a multicentre trial) into real-world practice, especially in the midst of a global pandemic. Further research is needed to establish the real-world effectiveness of the REACH-HF intervention in different populations.

Bridging the gap between oncology clinical trials and real-world data: evidence on replicability of efficacy results using German claims data

Aims: Using German claims, the authors replicated the CHAARTED trial in metastatic hormone-sensitive prostate cancer. Methods: The authors identified metastatic hormone-sensitive prostate cancer patients replicating the inclusion/exclusion criteria of CHAARTED. Patients treated with docetaxel in combination with androgen deprivation therapy (ADT) at first line (docetaxel group) were compared with patients treated with ADT monotherapy (ADT mono group). After propensity score matching, overall survival was compared between the matched cohorts. Results: The authors included 441 patients. After propensity score matching, two equally sized matched cohorts of 74 patients each were compared in terms of overall survival. The hazard ratio (HR) was 0.71 (95% CI: 0.42-1.19), comparable to the HR in CHAARTED (HR: 0.72; 95% CI: 0.59-0.89). Conclusions: Using early comparative evidence from real-world data for regulatory and health technology assessment decisions is useful.

Effects of ACE inhibitors and angiotensin receptor blockers: protocol for a UK cohort study using routinely collected electronic health records with validation against the ONTARGET trial

INTRODUCTION

Cardiovascular disease is a leading cause of death globally, responsible for nearly 18 million deaths worldwide in 2017. Medications to reduce the risk of cardiovascular events are prescribed based on evidence from clinical trials which explore treatment effects in an indicated sample of the general population. However, these results may not be fully generalisable because of trial eligibility criteria that generally restrict to younger patients with fewer comorbidities. Therefore, evidence of effectiveness of medications for groups underrepresented in clinical trials such as those aged ≥75 years, from ethnic minority backgrounds or with low kidney function may be limited.Using individual anonymised data from the Ongoing Telmisartan Alone and the Ramipril Global Endpoint Trial (ONTARGET) trial, in collaboration with the original trial investigators, we aim to investigate clinical trial replicability within a real-world setting in the area of cardiovascular disease. If the original trial results are replicable, we will estimate treatment effects and risk in groups underrepresented and excluded from the original clinical trial.

METHODS AND ANALYSIS

We will develop a cohort analogous to the ONTARGET trial within the Clinical Practice Research Datalink between 1 January 2001 and 31 July 2019 using the trial eligibility criteria and propensity score matching. The primary outcome is a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke and hospitalisation for congestive heart failure. If results from the cohort study fall within pre-specified limits, we will expand the cohort to include under represented and excluded groups.

ETHICS AND DISSEMINATION

Ethical approval has been granted by the London School of Hygiene & Tropical Medicine Ethics Committee (Ref: 22658). The study has been approved by the Independent Scientific Advisory Committee of the UK Medicines and Healthcare Products Regulatory Agency (protocol no. 20_012). Access to the individual patient data from the ONTARGET trial was obtained by the trial investigators. Findings will be submitted to peer-reviewed journals and presented at conferences.

Comparative Effectiveness of Dexamethasone in Hospitalized COVID-19 Patients in the United States

INTRODUCTION

To compare the mortality of hospitalized patients with COVID-19 between those that required supplemental oxygen and received dexamethasone with a comparable set of patients who did not receive dexamethasone.

METHODS

We utilized the Premier Health Database to identify hospitalized adult patients with COVID-19 from July 1, 2020-January 31, 2021. Index date was when patients first initiated oxygen therapy. The primary endpoint was in-hospital mortality for patients receiving dexamethasone versus those not receiving dexamethasone 1-day pre- to 1-day post-index period. Secondary endpoints included 28-day mortality, time to in-hospital mortality, progression to invasive mechanical ventilation or death, time to discharge, and proportion discharged alive by day 28. Twenty-three models using weighting, matching, stratification, and regression were deployed through the concept of frequentist model average (FMA) to estimate the effect of dexamethasone on all-cause mortality up to the 28-day hospitalization period.

RESULTS

A total of 1,208,881 patients with COVID-19 were screened; as an inpatient 255,216 used oxygen, and 251,536 were included in the analysis. In the dexamethasone group, odds of in-hospital mortality were higher than those of the comparator (FMA: odds ratio [OR] 1.15, 95% CI 1.08, 1.22). Using a best fit model, OR for in-hospital mortality was non-significant for the dexamethasone group compared with the comparator (OR 1.02, 95% CI 0.92, 1.14). Dexamethasone treatment was associated with poorer outcomes versus the comparator group across the majority of secondary endpoints, except for number of days in hospital, which was lower in the dexamethasone group versus the comparator group (mean difference - 2.14, 95% CI - 2.43, - 1.47).

CONCLUSIONS

Hospitalized adult patients with COVID-19 who required supplemental oxygen and received dexamethasone did not have a survival benefit versus similar patients not receiving dexamethasone. The dexamethasone group was not associated with favorable responses for outcomes such as progression to death or mechanical ventilation and time to in-hospital death.