Adaptive group-sequential design with population enrichment in phase 3 randomized controlled trials with two binary co-primary endpoints.

The use of co-primary endpoints in drug development allows investigators to capture an experimental intervention's multidimensional effect more comprehensively than a single primary endpoint. We propose the theoretical basis and development of an adaptive population enrichment design with co-primary endpoints, provide stage-wise boundary values for futility and efficacy, and discuss power under different efficacy configurations, subgroup prevalence, and analysis times using a pre-specified decision criterion. We considered a two-arm, two-stage, parallel group design where population enrichment occurs at the interim analysis by dropping any non-responsive subgroups. A test for efficacy is conducted only in the enriched population. Two binary endpoints are evaluated as co-primary endpoints. Our trial objective is to determine whether the experimental intervention is superior to the control intervention, with superiority required in both endpoints. We define the stopping boundary using alpha spending functions. Using a 0.025 significance level for each endpoint, we obtain the stage I threshold boundary values for futility and efficacy as -0.1040 and 2.2761, respectively, and the stage II boundary value for futility and efficacy is 2.2419. We show that in the presence of substantial heterogeneity of treatment effect, we gain more power to observe an effect in the subgroup where the benefits are greater. By allowing the dropping of non-responsive subgroups at an early stage, our design reduces the likelihood of obtaining false-negative results due to inclusion of the heterogeneous treatment effects of both subgroups, which would dilute the responsive subgroup's results.

Genetic Counseling Referral Rates in Long-Term Survivors of Triple-Negative Breast Cancer.

Background: Inherited BRCA gene mutations (pathogenic variants) cause 10% of breast cancers. BRCA pathogenic variants predispose carriers to triple-negative breast cancer (TNBC); around 30% of patients with TNBC carry BRCA pathogenic variants. The 2018 NCCN Guidelines for Genetic/Familial High-Risk Assessment: Breast and Ovarian recommend genetic counseling referrals for patients with TNBC diagnosed at age ≤60 years. This study sought to describe genetic counseling referral patterns among long-term TNBC survivors at The University of Texas MD Anderson Cancer Center. Methods: This single-institution retrospective analysis of female long-term (disease-free for ≥5 years) TNBC survivors sought to determine the rate of genetic counseling referral among patients diagnosed at age ≤60 years between 1992 and 2008. Patients who underwent treatment and surveillance visits at our institution and were followed until 2017 were included. We collected BRCA pathogenic variant status among tested patients. Descriptive statistical methods and a univariate analysis were used to identify patient characteristics associated with genetic counseling referral. Results: We identified 646 female long-term TNBC survivors with a median age at diagnosis of 47 years. Of these, 245 (38%) received a recommendation for a genetic counseling referral. Among those referred, 156 (64%) underwent genetic testing, and 35% of those tested had BRCA pathogenic variants. Interestingly, among those referred, 20% declined genetic testing. The rate of genetic referrals improved over time, from 25% among TNBC survivors whose last surveillance visit was between 2011 and 2013 to 100% among those whose last surveillance visit was between 2014 or later. Younger age and premenopausal status at diagnosis and a family history of breast or ovarian cancer were associated with an increased rate of referral for genetic counseling. Conclusions: Among long-term TNBC survivors, the rate of referral to genetic counseling increased over time, and among those tested, 35% carried a BRCA pathogenic variant. Survivorship care provides an excellent opportunity to refer eligible patients for genetic counseling.

Outcomes in patients with early-stage breast cancer who underwent a 21-gene expression assay.

BACKGROUND: Invasive disease-free survival (IDFS) rates are excellent in patients with breast cancer (BC) with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), axillary lymph node-negative (LN-) tumors with a 21-gene expression assay recurrence score (RS) of 0 to 10. However, to the authors' knowledge, the outcomes among patients with an RS of 11 to 25 who are treated with endocrine therapy alone are unknown. METHODS: In this retrospective single-institution study, the authors described the characteristics of patients with HR+, HER2-, LN- BC who underwent a 21-gene expression assay. In addition, among those individuals diagnosed between 2005 and 2011, we measured IDFS, recurrence-free survival, distant recurrence-free survival, and overall survival rates, focusing on patients with an RS of 11 to 25 by receipt of chemotherapy. The Kaplan-Meier method was used to estimate survival rates and multivariable Cox proportional hazards models were used to calculate hazard ratios and 95% confidence intervals (95% CIs). RESULTS: Among 1424 patients, the RS distribution was 0 to 10 in 297 patients (21%), 11 to 25 in 894 patients (63%), and >25 in 233 patients (16%); of these, 1.7%, 15%, and 73.4% of patients, respectively, received chemotherapy. With a median follow-up of 58 months, those patients with an RS of 11 to 25 had an IDFS rate at 5 years of 92.6% (95% CI, 89.6%-94.7%), which was comparable between those who received chemotherapy and those who did not. The hazard ratios of the effect of chemotherapy were 1.64 for IDFS (95% CI, 0.73-3.71), 1.46 for recurrence-free survival (95% CI, 0.41-5.23), 1.25 for distant recurrence-free survival (95% CI, 0.32-4.92), and 2.19 for overall survival (95% CI, 0.44-11.0). CONCLUSIONS: The results of the current study demonstrate similar outcomes with or without chemotherapy in patients with HR+, HER2-, LN- BC who have an RS of 11 to 25, but a benefit from chemotherapy in this group cannot be ruled out. Cancer 2017;123:2422-31. © 2017 American Cancer Society.

Mammographic breast density is associated with the development of contralateral breast cancer.

BACKGROUND: Women with dense mammographic breast density (BD) have a 2-fold increased risk of developing primary breast cancer (BC). The authors hypothesized that dense mammographic BD also is associated with an increased risk of developing contralateral breast cancer (CBC). METHODS: Among female patients treated at The University of Texas MD Anderson Cancer Center for sporadic, AJCC stage I to stage III BC between January 1997 and December 2012, the authors identified patients who had developed metachronous CBC (cases) and selected 1:2 matched controls who did not develop CBC using incidence density sampling, matched on attainted age, year of diagnosis, and hormone receptor status of the first BC. Mammographic BD, assessed at the time of first BC diagnosis, was categorized as "nondense" (American College of Radiology breast categories of fatty or scattered density) or "dense" (American College of Radiology categories of heterogeneously dense or extremely dense). Multivariable conditional logistic regression models were used for statistical analysis. RESULTS: A total of 229 cases and 451 controls were evaluated. Among the cases, approximately 39.3% had nondense breast tissue and 60.7% had dense breast tissue. Among controls, approximately 48.3% had nondense breast tissue and 51.7% had dense breast tissue. After adjustment for potential prognostic risk factors for BC, the odds of developing CBC were found to be significantly higher for patients with dense breasts (odds ratio, 1.80; 95% confidence interval, 1.22-2.64 [P<.01]) than for those with nondense breasts. Patients who received chemotherapy or endocrine therapy were less likely to develop CBC. CONCLUSIONS: In women with primary BC, mammographic BD appears to be a risk factor for the development of CBC. Cancer 2017;123:1935-1940. © 2017 American Cancer Society.

Five-year all-cause mortality rates across five categories of substantiated elder abuse occurring in the community.

Elder abuse increases the likelihood of early mortality, but little is known regarding which types of abuse may be resulting in the greatest mortality risk. This study included N = 1,670 cases of substantiated elder abuse and estimated the 5-year all-cause mortality for five types of elder abuse (caregiver neglect, physical abuse, emotional abuse, financial exploitation, and polyvictimization). Statistically significant differences in 5-year mortality risks were found between abuse types and across gender. Caregiver neglect and financial exploitation had the lowest survival rates, underscoring the value of considering the long-term consequences associated with different forms of abuse. Likewise, mortality differences between genders and abuse types indicate the need to consider this interaction in elder abuse case investigations and responses. Further mortality studies are needed in this population to better understand these patterns and implications for public health and clinical management of community-dwelling elder abuse victims.

FDA Approval Summary: Eflornithine for High-Risk Neuroblastoma Following Prior Multiagent, Multimodality Therapy.

On December 13, 2023, the U.S. Food and Drug Administration (FDA) approved eflornithine (IWILFIN, US WorldMeds) to reduce the risk of relapse in adult and pediatric patients with high-risk neuroblastoma who have demonstrated at least a partial response to prior multiagent, multimodality therapy including anti-GD2 immunotherapy. The approval was based on an externally controlled trial (ECT) consisting of a single-arm trial, Study 3(b), compared to an external control derived from a National Cancer Institute (NCI)/Children's Oncology Group (COG)-sponsored clinical trial (Study ANBL0032) and supported by confirmatory evidence. In the protocol-specified primary analysis, the event-free survival (EFS) hazard ratio (HR) was 0.48 (95% confidence interval [CI]: 0.27, 0.85) and overall survival (OS) HR was 0.32 (95% CI: 0.15, 0.70). The most common adverse reactions (≥5%) were hearing loss, otitis media, pyrexia, pneumonia, and diarrhea. Notably, this is the first oncology drug approval which relies on an ECT as the primary clinical data to support substantial evidence of effectiveness. This was made possible by a distinctly high-quality, comparable external control dataset with consistent treatment effect estimations demonstrated in multiple sensitivity and supportive analyses. Eflornithine's manageable safety profile and strong nonclinical and mechanistic data provided further support for the approval, and the evidentiary package was evaluated in the context of high unmet need in a rare, life-threatening cancer.

FDA Approval Summary: Atezolizumab as Adjuvant Treatment following Surgical Resection and Platinum-Based Chemotherapy for Stage II to IIIA NSCLC.

On October 15, 2021, the FDA approved atezolizumab as adjuvant therapy in patients with stage II to IIIA non-small cell lung cancer (NSCLC) whose tumors have programmed cell death ligand 1 (PD-L1) expression on ≥1% of tumor cells (TC), as detected by an FDA-approved test. The approval was based on results from the IMpower010 trial, in which 1,005 patients with NSCLC who had completed tumor resection and cisplatin-based adjuvant chemotherapy were randomly assigned 1:1 to receive atezolizumab for 16 cycles or best supportive care. The primary endpoint of disease-free survival (DFS) as assessed by investigator was tested hierarchically in the following analysis populations: stage II-IIIA NSCLC with PD-L1 expression on ≥1% of TCs (PD-L1 ≥ 1% TC); all randomly assigned patients with stage II-IIIA NSCLC; and the intent-to-treat population comprising all randomly assigned patients. At the prespecified interim DFS analysis, IMpower010 demonstrated a statistically significant and clinically meaningful improvement in DFS in the stage II-IIIA PD-L1 ≥ 1% TC analysis population, with an HR of 0.66 (95% confidence interval, 0.50-0.88; P = 0.004) favoring the atezolizumab arm. The safety profile of atezolizumab was generally consistent with known toxicities of anti-PD-(L) antibodies. The VENTANA PD-L1 (SP263) Assay (Ventana Medical Systems, Inc.) was contemporaneously approved as a companion diagnostic device to select patients with NSCLC who are PD-L1 ≥ 1% TC for adjuvant treatment with atezolizumab. Atezolizumab is the first immune checkpoint inhibitor approved by FDA for the adjuvant treatment of NSCLC.

Subgroup Analyses in Oncology Trials: Regulatory Considerations and Case Examples.

Subgroup analyses are assessments of treatment effects based on certain patient characteristics out of the total study population and are important for interpretation of pivotal oncology trials. However, appropriate use of subgroup analyses results for regulatory decision-making and product labeling is challenging. Typically, drugs approved by the FDA are indicated for use in the total patient population studied; however, there are examples of restriction to a subgroup of patients despite positive study results in the entire study population and also extension of an indication to the entire study population despite positive results appearing primarily in one or more subgroups. In this article, we summarize key issues related to subgroup analyses in the benefit-risk assessment of cancer drugs and provide case examples to illustrate approaches that the FDA Oncology Center of Excellence has taken when considering the appropriate patient population for cancer drug approval. In general, if a subgroup is of interest, the subgroup analysis should be hypothesis-driven and have adequate sample size to demonstrate evidence of a treatment effect. In addition to statistical efficacy considerations, the decision on what subgroups to include in labeling relies on the pathophysiology of the disease, mechanistic justification, safety data, and external information available. The oncology drug review takes the totality of the data into consideration during the decision-making process to ensure the indication granted and product labeling appropriately reflect the scientific evidence to support patient population for whom the drug is safe and effective.

Medication Regimen Complexity and Low Adherence in Older Community-Dwelling Adults With Substantiated Self-Neglect.

OBJECTIVE: Determine whether medication regimen complexity predicts medication adherence levels in a sample of community-dwelling adults 65 years and older with Adult Protective Services-substantiated self-neglect. METHODS: A cross-sectional analysis of baseline data ( N = 31 participants) from a pilot intervention to increase medication adherence among the target group was performed. The Medication Regimen Complexity Index (MRCI) and the 8-item Morisky Medication Adherence Scale (MMAS-8)™ were the primary independent and dependent measures, respectively. A multivariable linear regression analysis, adjusting for potential confounders, was conducted to estimate the association between complexity and adherence. RESULTS: Regimen complexity was high (mean MRCI = 19.6) and adherence was low (mean MMAS = 5.1). Even after controlling for confounders, increased complexity was significantly associated with lower adherence. DISCUSSION: Older community-dwelling adults who self-neglect have complex medication regimens that contribute to low medication adherence. Medication regimen complexity may be a modifiable contributor to low adherence that can be targeted by future interventions to reduce self-neglect and its consequences.

Determinants of Weight Gain During Adjuvant Endocrine Therapy and Association of Such Weight Gain With Recurrence in Long-term Breast Cancer Survivors.

BACKGROUND: Weight gain is a negative prognostic factor in breast cancer (BC) patients. The risk factors for weight gain during adjuvant endocrine therapy (ET) and the extent to which such weight gain is associated with disease recurrence remain unclear. PATIENTS AND METHODS: We retrospectively identified a cohort of women with a diagnosis of stage I-III, hormone receptor-positive, human epidermal growth factor receptor 2-negative BC from January 1997 to August 2008, who had received initial treatment at the MD Anderson Cancer Center, had completed 5 years of ET, and had remained free of locoregional or distant relapse or contralateral BC for ≥ 5 years after diagnosis. The weight change at the end of 5 years of ET was measured as the percentage of the change in weight from the start of ET, with a weight gain of > 5% considered clinically significant. Multivariable logistic regression and Cox proportional hazards models were used to assess the determinants of such weight gain and the risk of recurrence after 5 years. RESULTS: Of 1282 long-term BC survivors, 432 (33.7%) had a weight gain of > 5% after 5 years of ET. Women who were premenopausal at diagnosis were 1.40 times more likely than women who were postmenopausal at diagnosis to have a weight gain of > 5%. Asian women had the lowest risk of gaining weight. The recurrence risks of patients who had gained weight and those who had not were not significantly different. CONCLUSION: Premenopausal BC patients had an increased risk of weight gain after 5 years of ET; however, BC patients with a weight gain of > 5% did not have an increased risk of disease recurrence.

Location of Receipt of Initial Treatment and Outcomes in Long-Term Breast Cancer Survivors.

PURPOSE: Cancer outcomes differ depending on where treatment is received. We assessed differences in outcomes in long-term breast cancer survivors at a specialty care hospital by location of their initial treatment. METHODS: We retrospectively examined a cohort of women diagnosed with invasive early-stage breast cancer who did not experience recurrence for at least 5 years after the date of diagnosis and were evaluated at The University of Texas MD Anderson Cancer Center between January 1997 and August 2008. The location of initial treatment was categorized as MD Anderson (MDA-treated) or other (OTH-treated). Outcomes analyzed included recurrence-free survival (RFS), distant relapse-free survival (DRFS), and overall survival (OS). The Kaplan-Meier product-limit method was used to compare outcomes between the two groups. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI). RESULTS: We identified 5,091 breast cancer survivors (median follow-up 8.6 years), of whom 89.1% were MDA-treated. The 10-year OS, RFS, and DRFS rates were 90.9%, 88.4%, and 89.0% in the MDA-treated group and 74.3%, 49.8%, and 52.7% in the OTH-treated group, respectively. We observed worse outcomes in the OTH-group in both the univariate analysis and the multivariable analysis (OS: HR = 4.8, 95% CI = 3.9-6.0; RFS: HR = 5.8, 95% CI = 4.8-7.0; DRFS: HR = 5.4, 95% CI = 4.5-6.6). CONCLUSION: Long-term breast cancer survivors who initiated their treatment at MD Anderson had better outcomes. Location of initial treatment could be an independent risk factor for survival outcomes at specialty care hospitals. This analysis has limitations inherent to retrospective observational studies such as other unmeasured variables may be associated with worse prognosis.

Comparison of the global statistical test and composite outcome for secondary analyses of multiple coronary heart disease outcomes.

Multiple outcomes (or multiple endpoints), such as mortality and recurrent myocardial infarction, are increasingly common in clinical trials and are often of interest in secondary analyses. Traditionally, a clinical trial protocol is built around a single event as its primary outcome, with several secondary outcomes specified, the analyses for which lack the same level of power. To accommodate all the relevant outcomes and to increase the power of the comparison in trials evaluating the efficacy of treatments for coronary heart disease, investigators often chose to construct a composite outcome. The more conventional composite outcome fails to account for the relative importance and the relationship (correlation) among its components. The purpose of this work is to demonstrate the usefulness of the Global Statistical Test, which considers the correlation between multiple outcomes, as an alternative strategy for these situations and to demonstrate its effect on hypothesis testing and power analysis issues in comparison with the traditional composite outcome analysis. Data from the cardiovascular clinical trial Systolic Hypertension in the Elderly Population are used as an example.