Interpretability of Cancer Clinical Trial Results Using Restricted Mean Survival Time as an Alternative to the Hazard Ratio

Navigating the landscape of liver cancer management: Study designs in clinical trials and clinical practice

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer death worldwide and its prognosis is highly heterogeneous, being related not only to tumour burden but also to the severity of underlying chronic liver disease. Moreover, advances in systemic therapies for HCC have increased the complexity of patient management. Randomised-controlled trials represent the gold standard for evidence generation across all areas of medicine and especially in the oncology field, as they allow for unbiased estimates of treatment effect without confounders. Observational studies have many problems that could reduce their internal and external validity. However, large prospective (well-conducted) observational real-world studies can detect rare adverse events or monitor the occurrence of long-term adverse events. How best to harness real world data, which refers to data generated from the routine care of patients, and real-world 'evidence', which is the evidence generated from real-world data, represents an open challenge. In this review article, we aim to provide an overview of the benefits and limitations of different study designs, particularly focusing on randomised-controlled trials and observational studies, to address important and not fully resolved questions in HCC research.

Assessing the effect of metastasis-directed therapy in oligometastatic disease using the restricted mean survival time

BACKGROUND

Metastasis-directed therapy (MDT) with stereotactic body radiotherapy (SBRT) is emerging as an effective therapeutic option for oligometastatic disease (OMD). However, a lack of phase III data, consensus guidelines, and toxicity concerns limit its widespread use. Randomized controlled trials (RCTs) routinely report hazard ratios (HRs) and medians that lack clear clinical and robust interpretation. Restricted-mean survival time (RMST) is the duration of time a patient is expected to survive over the follow-up period, providing a robust and interpretable alternative. We analyzed the efficacy of SBRT using RMST.

METHODS

All registered RCTs of ablative radiotherapy in OMD in ClinicalTrials.gov through 2022 were identified. Data were reconstructed from Kaplan-Meier curves, and the HRs and RMST differences were estimated for surrogate endpoints (SEs) and overall survival (OS).

RESULTS

Six studies comprising 426 patients met the inclusion criteria. The RMST differences for SEs ranged from 4.6 months in a study by Iyengar et al. to 11.1 months in SABR-COMET. The RMST differences for OS in SABR-COMET, Gomez et al., and SINDAS studies were 12.6, 15 and 7.9 months, respectively.

CONCLUSION

RMST demonstrates the efficacy of local treatment in OMD. Representing the expected survival time, this method effectively communicates outcomes to patients and clinicians.

Optimal Donor Selection Across Multiple Outcomes For Hematopoietic Stem Cell Transplantation By Bayesian Nonparametric Machine Learning

Allogeneic hematopoietic cell transplantation (HCT) is one of the only curative treatment options for patients suffering from life-threatening hematologic malignancies; yet, the possible adverse complications can be serious even fatal. Matching between donor and recipient for 4 of the HLA genes is widely accepted and supported by the literature. However, among 8/8 allele matched unrelated donors, there is less agreement among centers and transplant physicians about how to prioritize donor characteristics like additional HLA loci (DPB1 and DQB1), donor sex/parity, CMV status, and age to optimize transplant outcomes. This leads to varying donor selection practice from patient to patient or via center protocols. Furthermore, different donor characteristics may impact different post transplant outcomes beyond mortality, including disease relapse, graft failure/rejection, and chronic graft-versus-host disease (components of event-free survival, EFS). We develop a general methodology to identify optimal treatment decisions by considering the trade-offs on multiple outcomes modeled using Bayesian nonparametric machine learning. We apply the proposed approach to the problem of donor selection to optimize overall survival and event-free survival, using a large outcomes registry of HCT recipients and their actual and potential donors from the Center for International Blood and Marrow Transplant Research (CIBMTR). Our approach leads to a donor selection strategy that favors the youngest male donor, except when there is a female donor that is substantially younger.

Identification of red blood cell distribution width as a prognostic factor in acute myeloid leukemia

Many prognostic factors have been identified in acute myeloid leukemia (AML). In this study, we investigated novel prognostic biomarkers using machine learning and Cox regression models in a prospective cohort of 591 patients with AML and tried to identify potential therapeutic targets based on transcriptomic data. We found that elevated red blood cell distribution width (RDW) at diagnosis was an adverse prognostic factor for AML, independent of the 2022 European LeukemiaNet (ELN2022) genetic risk. As a continuous variable, higher RDW was associated with shorter overall survival (OS) (hazard ratio [HR] 1.087, 95% confidence interval [CI] 1.036-1.139, p < 0.001) and event-free survival (EFS) (HR 1.078, 95% CI 1.033-1.124, p < 0.001). Elevated RDW returned to normal after consolidation therapy, which indicated that leukemia cells resulted in abnormal RDW. We further investigated the relationship between RDW and transcriptome in another cohort of 191 patients with AML and public datasets using gene set enrichment analysis (GSEA) and cell-type identification by estimating relative subsets of RNA transcripts (CIBERSORT). We found that patients in the high-RDW group were significantly enriched in the positive regulation of erythroid differentiation and inflammation-related pathways. Finally, we identified the inflammation-associated gene IL12RB2 and verified its prognostic relevance with patients with AML in public databases, suggesting it as a potential therapy target.

Adherence to GLP1-RA and SGLT2-I affects clinical outcomes and costs in patients with type 2 diabetes

AIMS

To evaluate the impact of adherence to glucagon like peptide-1 receptor agonists (GLP1-RA) and sodium-glucose transporter two inhibitors (SGLT2-I) on clinical outcomes and costs in patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

The 121,115 residents of the Lombardy Region (Italy) aged ≥40 years newly treated with metformin during 2007-2015 were followed to identify those who started therapy with GLP1-RA or SGLT2-I. Adherence to drug therapy over the first year was defined as the proportion of days covered >80%. Within each drug class, for each adherent patient, one non-adherent patient was matched for age, sex, duration, adherence to metformin treatment and propensity score. The primary clinical outcome was a composite of insulin initiation, hospitalisation for micro- and macrovascular complications and all-cause mortality after the first year of drug treatment. Costs were evaluated based on reimbursements from the national healthcare system.

RESULTS

After matching, 1182 pairs of adherent and non-adherent GLP1-RA users and 1126 pairs of adherent and non-adherent SGLT2-I users were included. In both groups, adherent patients experienced a significantly lower incidence of the primary outcome (HR: 0.85, 95% CI 0.72-0.98 for GLP1-RA and HR: 0.69, 95% CI 0.55-0.87 for SGLT2-I). A significant reduction in hospitalizations was found for adherent patients in the GLP1-RA group but not for the SGLT2-I group. Results were consistent when analyses were stratified by age and sex. While higher drug-related costs in the adherent group were counterbalanced by decreased hospitalisation costs in SGLT2-I treated patients, this was not the case for GLP1-RA.

CONCLUSIONS

Higher adherence to drug treatment with GLP1-RA and SGLT2-I during the first year of the drug intake is associated with a lower incidence of adverse clinical outcomes in a real-world setting.

Radiographic Progression Without Corresponding Prostate-specific Antigen Progression in Patients with Metastatic Castration-sensitive Prostate Cancer Receiving Apalutamide: Secondary Analysis of the TITAN Trial

BACKGROUND AND OBJECTIVE

In prostate cancer treated with androgen deprivation therapy (ADT), the initial sign of treatment resistance is often prostate-specific antigen (PSA) progression, followed by radiographic progression. However, the association between these two forms of progression remains unclear, especially in patients with metastatic castration-sensitive prostate cancer (mCSPC) treated with androgen receptor pathway inhibitors. We sought to evaluate the association between radiographic progression, PSA progression, and outcomes of apalutamide therapy in mCSPC.

METHODS

We analyzed individual participant-level data for patients randomized within the TITAN trial who experienced radiographic progression during follow-up (N = 326). This study investigated radiographic progression without simultaneous or preceding PSA progression, as defined by the Prostate Cancer Working Group 2 (discordant progression), and explored the association of such progression with radiographic progression-free survival.

KEY FINDINGS AND LIMITATIONS

Among the patients who developed radiographic progression, 115 (35.3%) had been treated with apalutamide plus ADT (the apalutamide group) and 211 (64.7%) with placebo plus ADT (the placebo group). Discordant progression occurred in 52.2% of patients (60 of 115) in the apalutamide group and 27.5% (58 of 211) in the placebo group (p < 0.001). A multivariable logistic regression analysis showed that discordant progression was associated with apalutamide treatment. We found evidence of an association between discordant progression and shorter radiographic progression-free survival.

CONCLUSIONS AND CLINICAL IMPLICATIONS

This study found that nearly half of the patients with mCSPC treated with apalutamide who experienced radiographic progression developed it without corresponding PSA progression, suggesting that heavy reliance on PSA monitoring may be inadequate for assessing disease activity in this context.

PATIENT SUMMARY

In patients who have metastatic castration-sensitive prostate cancer (mCSPC) and are being treated with apalutamide, radiographic images may show cancer progression even if prostate-specific antigen tests indicate no change. This highlights the importance of regular imaging when using apalutamide to manage mCSPC.

Simultaneous inference procedures for the comparison of multiple characteristics of two survival functions

Survival time is the primary endpoint of many randomized controlled trials, and a treatment effect is typically quantified by the hazard ratio under the assumption of proportional hazards. Awareness is increasing that in many settings this assumption is a priori violated, for example, due to delayed onset of drug effect. In these cases, interpretation of the hazard ratio estimate is ambiguous and statistical inference for alternative parameters to quantify a treatment effect is warranted. We consider differences or ratios of milestone survival probabilities or quantiles, differences in restricted mean survival times, and an average hazard ratio to be of interest. Typically, more than one such parameter needs to be reported to assess possible treatment benefits, and in confirmatory trials, the according inferential procedures need to be adjusted for multiplicity. A simple Bonferroni adjustment may be too conservative because the different parameters of interest typically show considerable correlation. Hence simultaneous inference procedures that take into account the correlation are warranted. By using the counting process representation of the mentioned parameters, we show that their estimates are asymptotically multivariate normal and we provide an estimate for their covariance matrix. We propose according to the parametric multiple testing procedures and simultaneous confidence intervals. Also, the logrank test may be included in the framework. Finite sample type I error rate and power are studied by simulation. The methods are illustrated with an example from oncology. A software implementation is provided in the R package nph.

Balancing Efficacy and Tolerability of First-Line Systemic Therapies for Advanced Hepatocellular Carcinoma: A Network Meta-Analysis

Background

Atezolizumab + bevacizumab represent the current standard of care for first-line treatment of advanced hepatocellular carcinoma (HCC). However, direct comparison with other combination treatments including immune checkpoint inhibitors (ICI) + tyrosine kinase inhibitors (TKIs) are lacking.

Objectives

This network meta-analysis (NMA) aims to indirectly compare the efficacy and the safety of first-line systemic therapies for unresectable advanced HCC.

Method

A literature search of MEDLINE, Embase, and SCOPUS databases was conducted up to October 31, 2022. Phase 3 randomized controlled trials (RCTs) testing TKIs, including sorafenib and lenvatinib, or ICIs reporting overall survival (OS) and progression-free survival (PFS) were included. Individual survival data were extracted from OS and PFS curves to calculate restricted mean survival time. A Bayesian NMA was performed to compare treatments in terms of efficacy (15- and 30-month OS, 6-month PFS) and safety, represented by grade ≥3 (severe) adverse events (SAEs). The incremental safety-effectiveness ratio as measure of net health benefit was calculated as the difference in SAE probability divided by survival difference between the 2 most effective treatments.

Results

Nine RCTs enrolling 6,600 patients were included. Atezolizumab plus bevacizumab showed the highest probability (88%) of achieving the 30-month OS landmark. Lenvatinib showed a probability of 86% of achieving best PFS outcomes. ICI monotherapies ranked as most tolerable. Atezolizumab plus bevacizumab showed the best net health benefit for OS, compared to durvalumab plus tremelimumab. When evaluating the net health benefit for PFS, at a willingness-to-risk threshold of 10% of SAEs for life-month gained, atezolizumab plus bevacizumab was favoured in 78% of cases, while at threshold of 30% of SAEs for life-month gained, lenvatinib was favoured in 76% of cases.

Conclusions

Atezolizumab plus bevacizumab is the best treatment in terms of net benefit and therefore it should be recommended as standard of care. Compared to atezolizumab plus bevacizumab, lenvatinib monotherapy had the best net benefit for PFS when physicians and patients are available to accept a higher risk of toxicity.

Effect of Laparoscopic and Open Pancreaticoduodenectomy for Pancreatic or Periampullary Tumors: Three-year Follow-up of a Randomized Clinical Trial

OBJECTIVE

This study aimed to estimate whether the potential short-term advantages of laparoscopic pancreaticoduodenectomy (LPD) could allow patients to recover in a more timely manner and achieve better long-term survival than with open pancreaticoduodenectomy (OPD) in patients with pancreatic or periampullary tumors.

BACKGROUND

LPD has been demonstrated to be feasible and may have several potential advantages over OPD in terms of shorter hospital stay and accelerated recovery than OPD.

METHODS

This noninferiority, open-label, randomized clinical trial was conducted in 14 centers in China. The initial trial included 656 eligible patients with pancreatic or periampullary tumors enrolled from May 18, 2018, to December 19, 2019. The participants were randomized preoperatively in a 1:1 ratio to undergo either LPD (n=328) or OPD (n=328). The 3-year overall survival (OS), quality of life, which was assessed using the 3-level version of the European Quality of Life-5 Dimensions, depression, and other outcomes were evaluated.

RESULTS

Data from 656 patients [328 men (69.9%); mean (SD) age: 56.2 (10.7) years] who underwent pancreaticoduodenectomy were analyzed. For malignancies, the 3-year OS rates were 59.1% and 54.3% in the LPD and OPD groups, respectively ( P =0.33, hazard ratio: 1.16, 95% CI: 0.86-1.56). The 3-year OS rates for others were 81.3% and 85.6% in the LPD and OPD groups, respectively ( P =0.40, hazard ratio: 0.70, 95% CI: 0.30-1.63). No significant differences were observed in quality of life, depression and other outcomes between the 2 groups.

CONCLUSION

In patients with pancreatic or periampullary tumors, LPD performed by experienced surgeons resulted in a similar 3-year OS compared with OPD.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03138213.

Association of Active Renin Content With Mortality in Critically Ill Patients: A Post hoc Analysis of the Vitamin C, Thiamine, and Steroids in Sepsis (VICTAS) Trial

OBJECTIVE

Sepsis is a leading cause of mortality. Predicting outcomes is challenging and few biomarkers perform well. Defects in the renin-angiotensin system (RAS) can predict clinical outcomes in sepsis and may outperform traditional biomarkers. We postulated that RAS dysfunction (elevated active renin, angiotensin 1-7 [Ang-(1-7)], and angiotensin-converting enzyme 2 (ACE2) activity with depressed Ang-II and ACE activity) would be associated with mortality in a cohort of septic patients.

DESIGN

Post hoc analysis of patients enrolled in the Vitamin C, Thiamine, and Steroids in Sepsis (VICTAS) randomized controlled trial.

SETTING

Forty-three hospitals across the United States.

PATIENTS

Biorepository samples of 103 patients.

INTERVENTIONS

We analyzed day 0 (within 24 hr of respiratory failure, septic shock, or both) and day 3 samples ( n = 103 and 95, respectively) for assessment of the RAS. The association of RAS values with 30-day mortality was determined using Cox proportional hazards regression with multivariable adjustments for age, sex, VICTAS treatment arm, systolic blood pressure, Sequential Organ Failure Assessment Score, and vasopressor use.

MEASUREMENTS AND MAIN RESULTS

High baseline active renin values were associated with higher 30-day mortality when dichotomized to the median of 188.7 pg/mL (hazard ratio [HR] = 2.84 [95% CI, 1.10-7.33], p = 0.031) or stratified into quartiles (Q1 = ref, HR Q2 = 2.01 [0.37-11.04], HR Q3 = 3.22 [0.64-16.28], HR Q4 = 5.58 [1.18-26.32], p for linear trend = 0.023). A 1- sd (593.6 pg/mL) increase in renin from day 0 to day 3 was associated with increased mortality (HR = 3.75 [95% CI, 1.94-7.22], p < 0.001), and patients whose renin decreased had improved survival compared with those whose renin increased (HR 0.22 [95% CI, 0.08-0.60], p = 0.003). Ang-(1-7), ACE2 activity, Ang-II and ACE activity did not show this association. Mortality was attenuated in patients with renin over the median on day 0 who received the VICTAS intervention, but not on day 3 ( p interaction 0.020 and 0.137, respectively). There were no additional consistent patterns of mortality on the RAS from the VICTAS intervention.

CONCLUSIONS

Baseline serum active renin levels were strongly associated with mortality in critically ill patients with sepsis. Furthermore, a greater relative activation in circulating renin from day 0 to day 3 was associated with a higher risk of death.

Identifying optimal ALK inhibitors in first- and second-line treatment of patients with advanced ALK-positive non-small-cell lung cancer: a systematic review and network meta-analysis

OBJECTIVES

To compare the efficacy, safety and effects on quality of life of different ALK-inhibitors for global and Asian patients with advanced ALK-positive non-small-cell lung cancer (NSCLC).

METHODS

The included RCTs were identified through a systematic search of PubMed, EMBASE, Cochrane Library, Clinical Trials.gov, and major cancer conferences. The assessment of progression-free survival (PFS), intracranial PFS, overall survival (OS), and patient-reported outcomes (PROs) was carried out using restricted mean survival time (RMST) model, fractional polynomial model and Royston-Parmar model. Time-invariant hazard ratio (HR) models were also used to validate and supplement the primary analysis. Objective response rate (ORR) and adverse events with any grade, grade 3-5 were assessed through a Bayesian network meta-analysis. The primary measures for OS, PFS, and PROs were HR and RMST. The odds ratio was the metric for evaluating safety, ORR, 12-month PFS rate, 24-month OS rate, and the 12-month non-deterioration rate of PROs. Subgroup analyses based on patient characteristics were performed.

RESULTS

A total of fourteen studies (ten for first-line, four for second-line) consisting of nine treatments (chemotherapy, crizotinib, alectinib [600mg BID], low-dose alectinib [300mg BID], brigatinib, ceritinib, ensartinib, envonalkib, and lorlatinib) were included. In the first-line setting, alectinib showed a significant advantage over crizotinib and had the longest OS among all ALK-inhibitors. Compared to crizotinib, lorlatinib had the best efficacy regarding PFS for global patients, followed closely by alectinib and brigatinib. For Asian patients, alectinib significantly improved PFS compared to other treatments. In second-line, alectinib had the highest PFS for patients pretreated with crizotinib, followed by brigatinib, ceritinib and chemotherapy. Alectinib, irrespective of the dose, was the safest first-line option, whereas lorlatinib, brigatinib, and ceritinib showed poorer safety profiles. Alectinib was also the safest ALK-inhibitor for crizotinib-resistant patients. Brigatinib had the best performance in terms of PROs.

CONCLUSIONS

Considering both efficacy and safety, alectinib appears to be the preferable treatment in first-line and second-line, particularly for Asian patients.

Real-World Treatment Patterns and Clinical Outcomes With Brentuximab Vedotin or Other Standard Therapies in Patients With Previously Treated Cutaneous T-Cell Lymphoma in the United States

INTRODUCTION/BACKGROUND

Primary cutaneous anaplastic large-cell lymphomas (pcALCLs) are a type of cutaneous T-cell lymphoma (CTCL) in which CD30 is uniformly expressed. In mycosis fungoides (MF), another CTCL, CD30 is heterogeneously expressed. In ALCANZA, patients with pcALCLs or CD30-positive MF randomized to brentuximab vedotin (BV) vs. physician's choice of methotrexate or bexarotene had significantly improved outcomes, including higher objective response rates (ORR) lasting ≥4 months (ORR4), as well as longer median progression-free survival (PFS) and time to next treatment (TTNT). In this study, we sought to assess the real-world impact of treatment with BV in second or later lines of therapy for CTCL.

MATERIALS AND METHODS

This retrospective chart review describes patient characteristics, treatment patterns, clinical outcomes, and healthcare resource use (HRU) in patients with pcALCLs or MF previously treated with ≥1 systemic therapy and subsequently treated with BV (n = 139) or other standard therapy (OST; n = 164).

RESULTS

Most patients in the BV cohort (96.4%) received BV as second-line (2L) systemic therapy. The most common OSTs were methotrexate (11.6%), mogamulizumab (9.1%), and bendamustine (9.1%) monotherapies. For 2L BV and OST, median duration of therapy was 8.4 and 5.2 months, real-world ORR was 82.1% and 66.5%, and real-world ORR4 was 42.5% and 25.0%. Real-world 1- and 2-year PFS, TTNT, and OS were significantly longer (all P < .01) and HRU was lower for BV vs. OST.

CONCLUSION

These real-world outcomes are consistent with ALCANZA results, demonstrating favorable outcomes with BV vs. OST in patients with CTCL previously treated with ≥1 systemic therapy.

Long-term outcomes of neoadjuvant immunotherapy plus chemotherapy in patients with early-stage triple-negative breast cancer: an extracted individual patient data and trial-level meta-analysis

BACKGROUND

Neoadjuvant immunotherapy (nIO) has emerged as a treatment option for stage II-III triple-negative breast cancer (TNBC). While randomised clinical trials (RCTs) demonstrated pathological complete response rate benefit to nIO added to chemotherapy, additional data on long-term outcomes is warranted. We performed this analysis to evaluate long-term efficacy outcomes of nIO in TNBC.

METHODS

We searched databases for RCTs evaluating nIO in early-stage TNBC. A meta-analysis of extracted individual patient data (EIPD) was performed to evaluate EFS and OS, with data from reported Kaplan-Meier plots. Additionally, we conducted a trial-level meta-analysis using fixed and random effects models.

RESULTS

The literature search resulted in four included RCTs with available EFS or OS (KEYNOTE-522, IMpassion031, I-SPY2 and GeparNuevo). EIPD showed that the addition of nIO to chemotherapy provides statistically significant benefits in EFS (HR 0.62, 0.50-0.76; p < 0.001) and OS (HR 0.62, 0.46-0.82, p < 0.001). Number needed to treat to avoid one EFS or OS event in 4 years was 9 and 14, respectively. Trial-level meta-analysis yielded similar results (EFS: HR 0.64, 0.51-0.79; OS: 0.57, 0.37-0.89).

CONCLUSIONS

Results show that nIO combined with chemotherapy can provide significant EFS and OS benefits, supporting its use as standard treatment for early-stage TNBC.

Long-term oncological outcomes of robotic versus laparoscopic gastrectomy for gastric cancer: multicentre cohort study

BACKGROUND

The aim of this multicentre cohort study was to compare the long-term oncological outcomes of robotic gastrectomy (RG) and laparoscopic gastrectomy (LG) for patients with gastric cancer.

METHODS

Patients with gastric cancer who underwent radical gastrectomy by robotic or laparoscopic approaches from 1 March 2010 to 31 December 2018 at 10 high-volume centres in China were selected from institutional databases. Patients receiving RG were matched 1 : 1 by propensity score with patients undergoing LG. The primary outcome was 3-year disease-free survival. Secondary outcomes were overall survival and disease recurrence.

RESULTS

Some 2055 patients who underwent RG and 4309 patients who had LG were included. The propensity score-matched cohort comprised 2026 RGs and 2026 LGs. Median follow-up was 41 (i.q.r. 39-58) months for the RG group and 39 (38-56) months for the LG group. The 3-year disease-free survival rates were 80.8% in the RG group and 79.5% in the LG group (log rank P = 0.240; HR 0.92, 95% c.i. 0.80 to 1.06; P = 0.242). Three-year OS rates were 83.9 and 81.8% respectively (log rank P = 0.068; HR 0.87, 0.75 to 1.01; P = 0.068) and the cumulative incidence of recurrence over 3 years was 19.3% versus 20.8% (HR 0.95, 0.88 to 1.03; P = 0.219), with no difference between groups.

CONCLUSION

RG and LG in patients with gastric cancer are associated with comparable disease-free and overall survival.

Sample size calculation for multi-arm parallel design with restricted mean survival time

With the recent advances in oncology treatment, restricted mean survival time (RMST) is increasingly being used to replace the routine approach based on hazard ratios in randomized controlled trials for time-to-event outcomes. While RMST has been widely applied in single-arm and two-arm designs, challenges still exist in comparing RMST in multi-arm trials with three or more groups. In particular, it is unclear in the literature how to compare more than one intervention simultaneously or perform multiple testing based on RMST, and sample size determination is a major obstacle to its penetration to practice. In this paper, we propose a novel method of designing multi-arm clinical trials with right-censored survival endpoint based on RMST that can be applied in both phase II/III settings using a global χ 2 test as well as a modeling-based multiple comparison procedure. The framework provides a closed-form sample size formula built upon a multi-arm global test and a sample size determination procedure based on multiple-comparison in the phase II dose-finding study. The proposed method enjoys strong robustness and flexibility as it requires less a priori set-up than conventional work, and obtains a smaller sample size while achieving the target power. In the assessment of sample size, we also incorporate practical considerations, including the presence of non-proportional hazards and staggered patient entry. We evaluate the validity of our method through simulation studies under various scenarios. Finally, we demonstrate the accuracy and stability of our method by implementing it in the design of two real clinical trial examples.

Prevention of atopic dermatitis in high-risk neonates via different types of moisturizer application: A randomized, blinded, parallel, three-group, phase II trial (PAF study)

BACKGROUND

The effectiveness of moisturizers in preventing infant atopic dermatitis (AD) remains unclear. We previously showed that using 2e moisturizer of commercial moisturizer (Shiseido Japan Co., Ltd.) at least once a day significantly prevented AD in infants as compared with as-needed petroleum jelly. This trial aimed to determine the effectiveness of twice- or once-daily application of Fam's Baby moisturizer (Fam's Inc.) in preventing AD compared with once-daily 2e moisturizer.

METHODS

This trial was a single-centre, three-parallel-group, assessor-blinded, superiority, individually randomized, controlled, phase II trial that was conducted from 25 August 2020 to 28 September 2021. We randomly assigned 60 newborns with at least one parent or sibling who has AD to receive Fam's Baby moisturizer twice daily (Group A) or once daily (Group B), or 2e once daily (Group C) in a 1:1:1 ratio until they were 32 weeks old. The primary outcome was the time of AD onset.

RESULTS

Atopic dermatitis was observed in 11/20 (55%), 5/20 (25%) and 10/20 (50%), infants in Groups A, B and C, respectively. Cumulative incidence values for AD according to the Kaplan-Meier method showed that infants in Group B tended to maintain an intact skin for a longer period than those in Group C (median time, not reached [NR] vs. 212 days, log-rank test, p = 0.064). Cox regression analysis showed that the risk of AD tended to be lower in Group B (hazard ratio with group C as control, 0.36; 95% confidential intervals: 0.12-1.06). No serious adverse events occurred in any of the enrolled infants.

CONCLUSION

Fam's Baby moisturizer may better prevent AD than 2e. Further large-scale trials should be performed to confirm the efficacy of Fam's Baby moisturizer in preventing AD in infants.

Statistical considerations in long-term efficacy evaluation of anti-cancer therapies

Anti-cancer therapy has been a significant focus of research. Developing and marketing various types and mechanisms of anti-cancer therapies benefit a variety of patients significantly. The long-term benefit to patients in evaluating the risk-benefit ratio of anti-cancer therapy has become a significant concern. This paper discusses the evaluation of long-term efficacy within the estimand framework and summarizes the various strategies for addressing potential intercurrent events. Non-proportional hazards of survival data may arise with novel anti-cancer therapies, leading to potential bias in conventional evaluation methods. This paper reviews statistical methods for addressing this issue, including novel endpoints, hypothesis testing, and efficacy estimation methods. We also discuss the influences of treatment switching. Although advanced methods have been developed to address the non-proportional hazard, they still have limitations that require continued collaborative efforts to resolve issues.

Challenges, Complexities, and Considerations in the Design and Interpretation of Late-Phase Oncology Trials

Optimal management of cancer patients relies heavily on late-phase oncology randomized controlled trials. A comprehensive understanding of the key considerations in designing and interpreting late-phase trials is crucial for improving subsequent trial design, execution, and clinical decision-making. In this review, we explore important aspects of late-phase oncology trial design. We begin by examining the selection of primary endpoints, including the advantages and disadvantages of using surrogate endpoints. We address the challenges involved in assessing tumor progression and discuss strategies to mitigate bias. We define informative censoring bias and its impact on trial results, including illustrative examples of scenarios that may lead to informative censoring. We highlight the traditional roles of the log-rank test and hazard ratio in survival analyses, along with their limitations in the presence of nonproportional hazards as well as an introduction to alternative survival estimands, such as restricted mean survival time or MaxCombo. We emphasize the distinctions between the design and interpretation of superiority and noninferiority trials, and compare Bayesian and frequentist statistical approaches. Finally, we discuss appropriate utilization of phase II and phase III trial results in shaping clinical management recommendations and evaluate the inherent risks and benefits associated with relying on phase II data for treatment decisions.

Trial Design for Cancer Immunotherapy: A Methodological Toolkit

Immunotherapy with checkpoint inhibitors (CPIs) and cell-based products has revolutionized the treatment of various solid tumors and hematologic malignancies. These agents have shown unprecedented response rates and long-term benefits in various settings. These clinical advances have also pointed to the need for new or adapted approaches to trial design and assessment of efficacy and safety, both in the early and late phases of drug development. Some of the conventional statistical methods and endpoints used in other areas of oncology appear to be less appropriate in immuno-oncology. Conversely, other methods and endpoints have emerged as alternatives. In this article, we discuss issues related to trial design in the early and late phases of drug development in immuno-oncology, with a focus on CPIs. For early trials, we review the most salient issues related to dose escalation, use and limitations of tumor response and progression criteria for immunotherapy, the role of duration of response as an endpoint in and of itself, and the need to conduct randomized trials as early as possible in the development of new therapies. For late phases, we discuss the choice of primary endpoints for randomized trials, review the current status of surrogate endpoints, and discuss specific statistical issues related to immunotherapy, including non-proportional hazards in the assessment of time-to-event endpoints, alternatives to the Cox model in these settings, and the method of generalized pairwise comparisons, which can provide a patient-centric assessment of clinical benefit and be used to design randomized trials.

Staging Chest CT in Patients With Early-Stage Colon Cancer: Analysis of Impact on Survival Using Inverse Probability Weighting and Causal Diagram

BACKGROUND. Staging chest CT has been shown to have negligible diagnostic yield for detecting lung metastases in patients with early-stage colon cancer. Nonetheless, staging chest CT may have potential survival benefits, including opportunistic screening of comorbidity and provision of a baseline examination for future comparisons. Evidence is lacking regarding the impact of staging chest CT on survival in patients with early-stage colon cancer. OBJECTIVE. The purpose of this study was to determine whether the performance of staging chest CT affects survival in patients with early-stage colon cancer. METHODS. This retrospective study included patients with early-stage colon cancer (defined as clinical stage 0 or I on staging abdominal CT) at a single tertiary hospital between January 2009 and December 2015. Patients were divided into two groups according to the presence of a staging chest CT examination. To ensure comparability between the two groups, inverse probability weighting was applied to adjust for the confounders derived from a causal diagram. The between-group differences in adjusted restricted mean survival time at 5 years were measured for overall survival, relapse-free survival, and thoracic metastasis-free survival. Sensitivity analyses were performed. RESULTS. A total of 991 patients (618 men and 373 women; median age, 64 years [IQR, 55-71 years]) were included: 606 patients (61.2%) had staging chest CT. For overall survival, the difference between groups in restricted mean survival time at 5 years was not significant (0.4 months [95% CI, -0.8 to 2.1 months]). The differences between groups in restricted mean survival at 5 years were also not significant for relapse-free survival (0.4 months [95% CI, -1.1 to 2.3 months]) and for thoracic metastasis-free survival (0.6 months [95% CI, -0.8 to 2.4 months]). Similar results were observed in sensitivity analyses that tested 3- and 10-year RMST differences, excluded patients who underwent FDG PET/CT during staging workup, and added treatment decision (surgery vs no surgery) to the causal diagram. CONCLUSION. The use of staging chest CT did not affect survival in patients with early-stage colon cancer. CLINICAL IMPACT. Staging chest CT may be omitted from the staging workup for patients with colon cancer of clinical stage 0 or I.

Adjuvant Therapy After Neoadjuvant Therapy for Esophageal Cancer: Who Needs It?

OBJECTIVE

We hypothesized that, on average, patients do not benefit from additional adjuvant therapy after neoadjuvant therapy for locally advanced esophageal cancer, although subsets of patients might. Therefore, we sought to identify profiles of patients predicted to receive the most survival benefit or greatest detriment from adding adjuvant therapy.

BACKGROUND

Although neoadjuvant therapy has become the treatment of choice for locally advanced esophageal cancer, the value of adding adjuvant therapy is unknown.

METHODS

From 1970 to 2014, 22,123 patients were treated for esophageal cancer at 33 centers on 6 continents (Worldwide Esophageal Cancer Collaboration), of whom 7731 with adenocarcinoma or squamous cell carcinoma received neoadjuvant therapy; 1348 received additional adjuvant therapy. Random forests for survival and virtual-twin analyses were performed for all-cause mortality.

RESULTS

Patients received a small survival benefit from adjuvant therapy (3.2±10 months over the subsequent 10 years for adenocarcinoma, 1.8±11 for squamous cell carcinoma). Consistent benefit occurred in ypT3-4 patients without nodal involvement and those with ypN2-3 disease. The small subset of patients receiving most benefit had high nodal burden, ypT4, and positive margins. Patients with ypT1-2N0 cancers had either no benefit or a detriment in survival.

CONCLUSIONS

Adjuvant therapy after neoadjuvant therapy has value primarily for patients with more advanced esophageal cancer. Because the benefit is often small, patients considering adjuvant therapy should be counseled on benefits versus morbidity. In addition, given that the overall benefit was meaningful in a small number of patients, emerging modalities such as immunotherapy may hold more promise in the adjuvant setting.

Omnibus test for restricted mean survival time based on influence function

The restricted mean survival time (RMST), which evaluates the expected survival time up to a pre-specified time point τ , has been widely used to summarize the survival distribution due to its robustness and straightforward interpretation. In comparative studies with time-to-event data, the RMST-based test has been utilized as an alternative to the classic log-rank test because the power of the log-rank test deteriorates when the proportional hazards assumption is violated. To overcome the challenge of selecting an appropriate time point τ , we develop an RMST-based omnibus Wald test to detect the survival difference between two groups throughout the study follow-up period. Treating a vector of RMSTs at multiple quantile-based time points as a statistical functional, we construct a Wald χ 2 test statistic and derive its asymptotic distribution using the influence function. We further propose a new procedure based on the influence function to estimate the asymptotic covariance matrix in contrast to the usual bootstrap method. Simulations under different scenarios validate the size of our RMST-based omnibus test and demonstrate its advantage over the existing tests in power, especially when the true survival functions cross within the study follow-up period. For illustration, the proposed test is applied to two real datasets, which demonstrate its power and applicability in various situations.

Testing the "RCT augmentation" methodology: A trial simulation study to guide the broadening of trials eligibility criteria and inform on effectiveness

Background

Exclusion criteria that are treatment effect modifiers (TEM) decrease RCTs results generalisability and the potentials of effectiveness estimation. In "augmented RCTs", a small proportion of otherwise-excluded patients are included to allow for effectiveness estimation. In Hodgkin Lymphoma (HL) RCTs, older age and comorbidity are common exclusion criteria, while also TEM. We simulated HL RCTs augmented with age or comorbidity, and explored in each scenario the impact of augmentation on effectiveness estimation accuracy.

Methods

Simulated data with a population of HL individuals initiating drug A or B was generated. There were drug-age and drug-comorbidity interactions in the simulated data, with a greater magnitude of the former compared to the latter. Multiple augmented RCTs were simulated by randomly selecting patients with increasing proportions of older, or comorbid patients. Treatment effect size was expressed using the between-group Restricted Mean Survival Time (RMST) difference at 3 years. For each augmentation proportion, a model estimating the "real-world" treatment effect (effectiveness) was fitted and the estimation error measured (Root Mean Square Error, RMSE).

Results

In simulated RCTs including none (0%), or the real-world proportion (30%) of older patients, the interquartile range of RMST difference was 0.4-0.5 years and 0.2-0.3 years, respectively, and RMSE were 0.198 years (highest possible error) and 0.056 years (lowest), respectively. Augmenting RCTs with 5% older patients decreased estimation error substantially (RMSE = 0.076 years). Augmentation with comorbid patients proved less useful for effectiveness estimation.

Conclusion

In augmented RCTs aiming to inform the effectiveness of drugs, augmentation should concern in priority those exclusion criteria of suspected important TEM magnitude, so as to minimie the proportion of augmentation necessary for good effectiveness estimations.

Regorafenib versus Cabozantinib as a Second-Line Treatment for Advanced Hepatocellular Carcinoma: An Anchored Matching-Adjusted Indirect Comparison of Efficacy and Safety

INTRODUCTION

The tyrosine kinase inhibitors regorafenib and cabozantinib remain the mainstay in second-line treatment of advanced hepatocellular carcinoma (HCC). There is currently no clear evidence of superiority in efficacy or safety to guide choice between the two treatments.

METHODS

We conducted an anchored matching-adjusted indirect comparison using individual patient data from the RESORCE trial of regorafenib and published aggregate data from the CELESTIAL trial of cabozantinib. Second-line HCC patients with prior sorafenib exposure of ≥3 months were included in the analyses. Hazard ratios (HRs) and restricted mean survival time (RMST) were estimated to quantify differences in overall survival (OS) and progression-free survival (PFS). Safety outcomes compared were rates of grade 3 or 4 adverse events (AEs), occurring in >10% of patients, and discontinuation or dose reduction due to treatment-related AEs.

RESULTS

After matching adjustment for differences in baseline patient characteristics, regorafenib showed a favorable OS (HR, 0.80; 95% CI: 0.54, 1.20) and ∼3-month-longer RMST over cabozantinib (RMST difference, 2.76 months; 95% CI: -1.03, 6.54), although not statistically significant. For PFS, there was no numerical difference in HR (HR, 1.00; 95% CI: 0.68, 1.49) and no clinically meaningful difference based on RMST analyses (RMST difference, -0.59 months; 95% CI: -1.83, 0.65). Regorafenib showed a significantly lower incidence of discontinuation (risk difference, -9.2%; 95% CI: -17.7%, -0.6%) and dose reductions (-15.2%; 95% CI: -29.0%, -1.5%) due to treatment-related AEs (any grade). Regorafenib was also associated with a lower incidence (not statistically significant) of grade 3 or 4 diarrhea (risk difference, -7.1%; 95% CI: -14.7%, 0.4%) and fatigue (-6.3%; 95% CI: -14.6%, 2.0%).

CONCLUSION

This indirect treatment comparison suggests, relative to cabozantinib, that regorafenib could be associated with favorable OS (not statistically significant), lower rates of dose reductions and discontinuation due to treatment-related AEs, and lower rates of severe diarrhea and fatigue.

Assessment of Median and Mean Survival Time in Cancer Clinical Trials

This cohort study assesses the relative stability of median and mean survival time estimates reported in cancer clinical trials.

Quantifying and Interpreting the Prediction Accuracy of Models for the Time of a Cardiovascular Event-Moving Beyond C Statistic: A Review

Importance

For personalized or stratified medicine, it is critical to establish a reliable and efficient prediction model for a clinical outcome of interest. The goal is to develop a parsimonious model with fewer predictors for broad future application without compromising predictability. A general approach is to construct various empirical models via individual patients' specific baseline characteristics/biomarkers and then evaluate their relative merits. When the outcome of interest is the timing of a cardiovascular event, a commonly used metric to assess the adequacy of the fitted models is based on C statistics. These measures quantify a model's ability to separate those who develop events earlier from those who develop them later or not at all (discrimination), but they do not measure how closely model estimates match observed outcomes (prediction accuracy). Metrics that provide clinically interpretable measures to quantify prediction accuracy are needed.

Observations

C statistics measure the concordance between the risk scores derived from the model and the observed event time observations. However, C statistics do not quantify the model prediction accuracy. The integrated Brier Score, which calculates the mean squared distance between the empirical cumulative event-free curve and its individual patient's counterparts, estimates the prediction accuracy, but it is not clinically intuitive. A simple alternative measure is the average distance between the observed and predicted event times over the entire study population. This metric directly quantifies the model prediction accuracy and has often been used to evaluate the goodness of fit of the assumed models in settings other than survival data. This time-scale measure is easier to interpret than the C statistics or the Brier score.

Conclusions and Relevance

This article enhances our understanding of the model selection/evaluation process with respect to prediction accuracy. A simple, intuitive measure for quantifying such accuracy beyond C statistics can improve the reliability and efficiency of the selected model for personalized and stratified medicine.

Fixation of intra-articular calcaneal fractures: A comparative study of the postoperative outcome between HA/PPLA screws and locking plates

Background

Forged unsintered hydroxyapatite and poly l-lactic acid (F-u-HA/PLLA) screw is bioactivite, bioabsorbable, and radiopaque with high mechanical strength. Its efficacy has been previously demonstrated in the treatment of lateral humeral condylar, lateral tibial condylar, ankle, and patellar fractures. However, studies on its efficacy in treatment of calcaneal fractures is lacking. This study aimed to compare the postoperative results of F-u-HA/PLLA screw fixation and locking plate fixation for intra-articular calcaneal fractures.

Methods

From January 2013 to December 2019, 47 closed intra-articular fractures treated with either F-u-HA/PLLA screws (group S, 18 feet in 17 patients) or locking plates (group P, 29 feet in 28 patients) in a single trauma center were retrospectively reviewed. The sinus tarsi approach was used in both groups. The time to bone union, step-off, varus deformity, Bohler's angle, and width and height of the calcaneus were assessed after surgery. Ankle joint range of motion (ROM) and postoperative complications were also assessed.

Results

All fractures were successfully treated. The Kaplan-Meier curves of the two groups showed similar trends. The log-rank test showed no significant difference in the time to bone union between the two groups (p = 0.48). In the Cox proportional hazards model adjusted for preoperative width and Bohler's angle, the hazard ratio for bone union was not statistically significant (HR: 1.13, 95%CI: 0.50-2.56, p = 0.78). Other variables included step-off (group S: 2.0 vs group P: 2.2 mm, p = 0.84), varus deformity (2.0° vs. 3.0°, p = 0.7), Gissane's angle (103.5° vs 104.0°, p = 0.84), width (38.0 vs 34.8 mm, p = 0.12), height (42.1 vs 44.0 mm, p = 0.07), and ankle ROM degrees (dorsal flexion, 20.0° vs. 20.0°, p = 0.13; plantar flexion 40.0° vs 40.0°, p = 0.56), which were not significantly different between groups P and S. The Bohler's angle was smaller in group S than in group P (20.5° vs 27.0°, p < 0.01). No skin necrosis or infection was observed in either group.

Conclusion

Postoperative results of F-u-HA/PLLA screw fixation using the sinus tarsi approach for intra-articular calcaneal fractures were as good as those of locking plate fixation.

Sensitivity Analysis for Restricted Mean Survival Time When Survival Curves Have Divergent Tails

New immunotherapy methods are being developed to provide cancer patients with survival benefit. The tail effect of immuno-oncology (IO) therapy resulting in diverse tails of survival curves between treatment arms may provide important information for physicians to guide treatment decisions in clinical practice. The hazard ratio (HR) and the log-rank test may not be suitable for quantifying and interpreting the between-group difference in IO clinical trials because the underlying assumption that the HR is constant over time is not valid. As an alternative summary measure, the restricted mean survival time (RMST) has been attracting more attention for comparing survival curves. The RMST is defined as the mean survival time to a specific threshold timepoint τ and is calculated as the area under the curve within a specific time window from 0 to τ. Although physicians may wish to compare the RMST up to the end timepoint of a longer curve to elucidate the tail effect of the IO treatment, with the currently available statistical methods, τ is required to be set at the end timepoint of a shorter curve or before. To address this issue, we propose a sensitivity analysis approach to evaluating the between-group difference in the RMST at any timepoint that clinical investigators consider clinically relevant, thus being free from such a statistical constraint. Notably, this analysis can only provide complementary results; thus, it cannot function as the primary analysis.

Performance of Restricted Mean Survival Time Based Methods and Traditional Survival Methods: An Application in an Oncological Data

Objective

To compare restricted mean survival time- (RMST-) based methods with traditional survival methods when multiple covariates are of interest.

Methods

4405 osteosarcomas were captured from Surveillance, Epidemiology, and End Results Program Database. RMST-based methods included group comparison using Kaplan-Meier (KM) method, pseudovalue (PV) regression, and inverse probability of censoring probability (IPCW) regressions with group-specific and individual weights. Log-rank test, Wilcoxon test, Cox regression, and its extension with time-dependent variables were selected as traditional methods. Proportional hazard (PH) assumption and homogeneity of censoring mechanism assumption were assessed. We estimated hazard ratio (HR) and difference in RMST and explored their relationships.

Results

When covariate violated PH assumption, time-varying HR was inconvenient to report as a single value but PH assumption-free RMST allowed to report a single value of difference in RMST. In univariable analyses, using the difference in RMST calculated by KM method as reference, PV regressions (slope = 1.02 and R ² = 0.98) and IPCW regressions with group-specific weights (slope = 0.98 and R ² = 0.99) gave more consistent estimation than IPCW with individual weights (slope = 0.31 and R ² = 0.06), moreover, PV regressions presented more robust statistical power than IPCW regressions with group-specific weights. In multivariable analyses, IPCW regression with group-specific weights was limited when multiple covariates violated homogeneity of censoring mechanism assumption. For covariates met PH assumption, well-fitted logarithmic relationships between HR and difference in RMST estimated by PV regression were observed in both univariable and multivariable analyses (R ² = 0.97 and R ² = 0.94, respectively), which supported the robustness of PV regression and possible conversion between the two effect measures.

Conclusions

Difference in RMST is more interpretable than time-varying HR. The performance supports KM method and PV regression to be the preferred ones in RMST-based methods. IPCW regression can be an alternative sensitivity analysis. We encourage adoption of both traditional methods and RMST-based methods to present effects of covariates comprehensively.

Analysis of new treatments proposed for malignant pleural mesothelioma raises concerns about the conduction of clinical trials in oncology

In this commentary, using existing clinical trial data and FDA approvals we propose that there is currently a critical need for an appropriate balancing between the financial impact of new cancer drugs and their actual benefit for patients. By adopting "pleural mesothelioma" as our clinical model we summarize the most relevant pertinent and available literature on this topic, and use an analysis of the reliability of the trials submitted for registration and/or recently published as a case in point to raise concerns with respect to appropriate trial design, biomarker based stratification and to highlight the ongoing need for balancing the benefit/cost ratio for both patients and healthcare providers.

Restricted Mean Survival Time Analysis to Estimate SGLT2i-Associated Heterogeneous Treatment Effects on Primary and Secondary Prevention of Cardiorenal Outcomes in Patients With Type 2 Diabetes in Taiwan

IMPORTANCE

Increasing numbers of post hoc analyses have applied restricted mean survival time (RMST) analysis on the aggregated-level data from clinical trials to report treatment effects, but studies that use individual-level claims data are needed to determine the feasibility of RMST analysis for quantifying treatment effects among patients with type 2 diabetes in routine clinical settings.

OBJECTIVES

To apply RMST analysis for assessing sodium-glucose cotransporter-2 inhibitor (SGLT2i)-associated cardiovascular (CV) events and estimating heterogenous treatment effects (HTEs) on CV and kidney outcomes in routine clinical settings.

DESIGN, SETTING, AND PARTICIPANTS

This comparative effectiveness study of Taiwan's National Health Insurance Research Database examined 21 144 propensity score (PS)-matched pairs of patients with type 2 diabetes with SGLT2i and dipeptidyl peptidase-4 inhibitor (DPP4i) treatment for assessing CV outcomes, and 19 951 PS-matched pairs of patients with type 2 diabetes with SGLT2i and DPP4i treatment for assessing kidney outcomes. Patients were followed until December 31, 2018. Statistical analysis was performed from August 2021 to April 2022.

EXPOSURES

Newly stable SGLT2i or DPP4i use in 2017.

MAIN OUTCOMES AND MEASURES

Study outcomes were CV events including hospitalization for heart failure (HHF), 3-point major adverse CV events (3P-MACE: nonfatal myocardial infarction [MI], nonfatal stroke, and CV death), 4-point MACE (4P-MACE: HHF and 3P-MACE), and all-cause death, and chronic kidney disease (CKD). RMST and Cox modeling analyses were applied to estimate treatment effects on study outcomes.

RESULTS

After PS matching, the baseline patient characteristics were comparable between 21 144 patients with stable SGLT2i use (eg, mean [SD] age: 58.3 [10.7] years; 11 990 [56.7%] male) and 21 144 patients with stable DPP4i use (eg, mean [SD] age: 58.1 [11.6] years; 12 163 [57.5%] male) for assessing CV outcomes, and those were also comparable between 19 951 patients with stable SGLT2i use (eg, mean [SD] age: 58.1 [10.7] years; 11 231 [56.2%] male) and 19 951 patients with stable DPP4i use (eg, mean [SD] age: 57.9 [11.5] years; 11 340 [56.8%] male) for assessing kidney outcome. The 2-year difference in RMST between patients with SGLT2i use and patients with DPP4i use was 4.99 (95% CI, 3.56-6.42) days for HHF, 4.12 (95% CI, 2.72-5.52) days for 3P-MACE, 7.72 (95% CI, 5.83-9.61) days for 4P-MACE, 1.26 (95% CI, 0.47-2.04) days for MI, 2.70 (95% CI, 1.57-3.82) days for stroke, 0.69 (95% CI, 0.28-1.11) days for CV death, 6.05 (95% CI, 4.89-7.20) days for all-cause death, and 14.75 (95% CI, 12.99-16.52) days for CKD. Directions of hazard ratios from Cox modeling analyses were consistent with RMST estimates. No association was found between study treatment and the negative control outcome (dental visits for tooth care). Consistent results across sensitivity analyses using high-dimensional PS-matched and PS-weighting approaches supported the validity of primary analysis results. Largest difference in RMST of SGLT2i vs DPP4i use for HHF and CKD was found among patients with established heart failure (30.80 [95% CI, 5.08-56.51] days) and retinopathy (40.43 [95% CI, 31.74-49.13] days), respectively.

CONCLUSIONS AND RELEVANCE

In this comparative effectiveness study, RMST analysis was feasible for translating treatment effects into more clinical intuitive estimates and valuable for quantifying HTEs among diverse patients in routine clinical settings.

Association of systemic inflammatory and autoimmune manifestations with myelodysplastic syndromes: A systematic review and meta-analysis

BACKGROUND

Systemic inflammatory and autoimmune manifestations (SIAMs) are frequently reported in Myelodysplastic syndromes (MDS). Studies focused on the impact of SIMAs on survival outcomes of MDS remains controversial. We performed this systematic review and meta-analysis to determine the association of SIAMs with overall survival, median survival, rate of acute myeloid leukemia transformation and mortality of MDS.

MATERIALS AND METHODS

An electronic search was conducted in 4 databases without any language restrictions, including PubMed, EMBASE, Medicine and Cochrane library up to April 30, 2021.

RESULTS

The 18 studies included a total of 4603 MDS patients, of which 1175 (25.5%) patients had SIAMs. MDS patients with SIAMs had a statistically shorter overall survival compared with patient without SIAMs (Hazard ratio, 2.43; 95% confidence interval [CI], 1.34-4.41; P < .01). Our results were most compatible with no effect of SIAMs on median survival, rate of acute myeloid leukemia transformation and mortality (Median survival ratio, 1.16; 95% CI, 0.91-1.47; Odds ratio, 0.96; 95% CI, 0.63-1.45 and 1.2; 95% CI, 0.84-1.7, respectively).

CONCLUSION

In this systematic review and meta-analysis, SIAMs appeared to have an adverse effect on overall survival of MDS patients. This finding suggested that SIAMs may be a potential independent prognostic factor for MDS.

A systematic review and network meta-analysis of first-line immune checkpoint inhibitor combination therapies in patients with advanced non-squamous non-small cell lung cancer

Introduction

Clinical evidence suggests that first-line immune checkpoint inhibitor (ICI) combination therapies can improve survival in patients with advanced non-squamous non-small cell lung cancer (nsq-NSCLC). However, the optimal strategy remains unknown without a systematic comparison of their long-term effects.

Methods

We performed a systematic review and network meta-analysis by retrieving up-to-date literature from PubMed® (National Library of Medicine, Bethesda, MD, USA), Embase® (Elsevier, Amsterdam, Netherlands), MEDLINE® (National Library of Medicine), ClinicalTrials.gov (National Library of Medicine), and major international conference publications. Published studies and abstracts comparing first-line ICI combination therapies with other treatments for patients with advanced nsq-NSCLC were included. Restricted mean survival time (RMST) was measured over 12 months for progression-free survival (PFS) and 18 months for overall survival (OS), and the Royston–Parmar model was used to extrapolate and compare data for the long-term outcomes.

Results

We included a total of 11 trials involving 12 therapies and 6,130 patients. Pembrolizumab plus chemotherapy exhibited the best overall survival (OS) benefit at both 18 and 60 months [RMST = 2.95, 95% confidence interval (CI) 1.96 to 3.97; life-years gained over a 5-year period = 2.18 years]. Nivolumab plus bevacizumab plus chemotherapy was found to present the best progression-free survival (PFS) benefit at 12 months (RMST 3.02, 95% CI 2.11 to 3.91), whereas atezolizumab plus bevacizumab plus chemotherapy showed the best PFS benefit at 36 months (life-years gained over 3 years = 1.22 years). Subgroup analyses showed that among patients with programmed death-ligand 1 (PD-L1) expression ≥ 50%, atezolizumab plus chemotherapy and nivolumab plus ipilimumab resulted in superior OS benefits at 18 and 60 months, respectively. Among patients with PD-L1 expression&lt; 1%, pembrolizumab plus chemotherapy was associated with OS benefits at both 18 and 60 months. Sintilimab plus chemotherapy was associated with relatively fewer grade ≥ 3 adverse events than other ICI combination therapies.

Conclusion

Our results show that ICI combination therapies showed better survival benefits than chemotherapy. Pembrolizumab plus chemotherapy could provide the best OS benefits to patients with advanced nsq-NSCLC, whereas atezolizumab plus bevacizumab plus chemotherapy could bring the best PFS benefits. The optimal ICI combination therapy varies depending on PD-L1 expression level.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=325005, identifier CRD42022325005.

EUS-guided ablation with the HybridTherm Probe as second-line treatment in patients with locally advanced pancreatic ductal adenocarcinoma: A case-control study

Background and Objectives

Data on the clinical efficacy of EUS-guided ablation using the HybridTherm-Probe (EUS-HTP) in locally advanced pancreatic ductal adenocarcinoma (LA-PDAC) are lacking. The aim of the study was to assess the impact of EUS-HTP added to chemotherapy (CT) on overall survival (OS) and progression-free survival (PFS) of LA-PDAC patients with local disease progression (DP) after first-line therapy, compared to CT alone in controls.

Methods

LA-PDAC cases, prospectively treated by EUS-HTP, were retrospectively compared to matched controls (1:2) receiving standard treatment. Study endpoints were the OS and PFS from local DP after first-line therapy, compared through log-rank test calculating hazard ratios and differences in restricted mean OS/PFS time (RMOST/RMPFST) within prespecified time points (4, 6, and 12 months).

Results

Thirteen cases and 26 controls were included. Clinical, tumor, and therapy features before and after first-line therapy were case-control balanced. The median OS and PFS were not significantly improved in cases over controls (months: 7 vs. 5 and 5 vs. 3, respectively). At 4 and 6 months, the RMPFST difference was in favor of cases (P = 0.0001 and P = 0.003, respectively). In cases and controls not candidate to further CT (N = 5 and N = 9), the median OS and PFS were not significantly improved in cases over controls (months: 6 vs. 3 and 4 vs. 2, respectively), but the RMPFST difference was in favor of cases at 4 months (P = 0.002).

Conclusions

In locally progressive PDAC patients experiencing failure of first-line therapy, EUS-HTP achieves a significantly better RMPFST up to 6 months compared to standard treatment, although without a significant impact on OS.

The Impact of Sequence of Therapy for Older Patients With Follicular Lymphoma: SEER-Medicare Analysis

BACKGROUND

One key clinical challenge remains in how to sequence treatments in follicular lymphoma (FL). The chemoimmunotherapy rituximab cyclophosphamide, doxorubicin, vincristine (Oncovin), and prednisone (R-CHOP) has been a standard treatment option for two decades. However, there are limited data to suggest in which line R-CHOP should be used for older patients.

PATIENTS AND METHODS

We leveraged population-based surveillance, epidemiology, and end results-medicare data and identified 675 patients aged ≥65 years newly diagnosed with FL from 2000 to 2009 who received R-CHOP in either the first or second line. We estimated restricted mean survival time using Kaplan-Meier curves, propensity scores (PS), and regression models comparing patients who received R-CHOP as a first versus second line.

RESULTS

We found that patients who received R-CHOP as first line had significantly longer 9-year RMST than those who received R-CHOP in the second line using Kaplan-Meier curves (P = .01), PS stratification (P = .002), PS matching (P = .005), and the inverse of PS as the treatment weight (P < .0001). The subgroup analyses using linear regression models showed that the 9-year restricted mean survival time of patients who received R-CHOP as the first line was longer in patients aged ≥80 years (P = .002) and with histological grade 1 or 2 (P = .02), compared to those who received R-CHOP as second line.

CONCLUSION

R-CHOP given in the first line was associated with longer overall survival compared to R-CHOP given as second line for older patients with FL.

Handling Informative Premature Treatment or Study Discontinuation for Assessing Between-Group Differences in a Comparative Oncology Trial

This decision analytical model study examines premature treatment discontinuation in clinical trials for patients with advanced renal cell carcinoma.

Immunotherapy in advanced kidney cancer: an alternative meta-analytic method using reconstructed survival data in case of proportional hazard assumption violation

Background

With the advent of immuno-oncology compounds in randomized trials, we observe more and more survival curves crossing. From a statistical standpoint this corresponds to violation of the proportional hazard assumption. When this occurs, the hazard ratio from the Cox regression is not reliable as an estimate. Herein, we aimed to identify the most appropriate IO-based therapy for metastatic renal cell carcinoma applying an alternative method to overcome the issue of hazard assumption violation for meta-analyses.

Methods

Pubmed, EMBASE, Web of Science and Scopus databases were searched. Only phase III randomized clinical trials on IO-IO (nivo-ipi) or IO-TKI combinations were included. An algorithm to obtain survival data from published Kaplan-Meier curves was used to reconstruct data on overall survival (OS), progression-free survival (PFS) and duration of response (DoR). Differences in restricted mean survival time (RMST) were used for comparisons.

Results

individual survival data from 4,206 patients from five trials were reconciled. Patients who received nivo-ipi or IO-TKI had better OS, PFS and DoR relative to sunitinib (all p<0.001). Patients who received IO-TKI had similar OS and PFS relative to nivo-ipi, with a 36-month ΔRMST of -0.55 (95% CI: -1.71-0.60; p=0.3) and -1.5 (95% CI: -2.9-0.0; p=0.051) months, respectively. Regarding DoR, patients who received nivo-ipi had longer duration of response relative to IO-TKI, with a 24-month ΔRMST of 1.5 (95% CI: 0.2-2.8; p=0.02) months.

Conclusion

Despite overall similar OS and PFS for patients receiving nivo-ipi and IO-TKI combinations, DoR was more favorable in patients who received nivo-ipi compared to IO-TKI. A meta-analysis based on differences in RMST is a useful alternative whenever the proportional hazard assumption is violated.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/, identifier CRD42021241421.