Single-arm studies involving patient-reported outcome data in oncology: a literature review on current practice.

Patient-reported outcomes (PROs) are increasingly used in single-arm cancer studies. We reviewed 60 papers published between 2018 and 2021 of single-arm studies of cancer treatment with PRO data for current practice on design, analysis, reporting, and interpretation. We further examined the studies' handling of potential bias and how they informed decision making. Most studies (58; 97%) analysed PROs without stating a predefined research hypothesis. 13 (22%) of the 60 studies used a PRO as a primary or co-primary endpoint. Definitions of PRO objectives, study population, endpoints, and missing data strategies varied widely. 23 studies (38%) compared the PRO data with external information, most often by using a clinically important difference value; one study used a historical control group. Appropriateness of methods to handle missing data and intercurrent events (including death) were seldom discussed. Most studies (51; 85%) concluded that PRO results supported treatment. Conducting and reporting of PROs in cancer single-arm studies need standards and a critical discussion of statistical methods and possible biases. These findings will guide the Setting International Standards in Analysing Patient-Reported Outcomes and Quality of Life Data in Cancer Clinical Trials-Innovative Medicines Initiative (SISAQOL-IMI) in developing recommendations for the use of PRO-measures in single-arm studies.

Time to deterioration of symptoms or function using patient-reported outcomes in cancer trials.

Time-to-event endpoints for patient-reported outcomes, such as time to deterioration of symptoms or function, are frequently used in cancer clinical trials. Although time-to-deterioration endpoints might seem familiar to cancer researchers for being similar to survival or disease-progression endpoints, there are unique considerations associated with their use. The complexity of time-to-deterioration endpoints should be weighed against the information that they add to the tumour, survival, and safety data used to inform the risks and benefits of an investigational drug. Here we use the estimand framework to show how analytical decisions answer different clinical questions of interest, some of which might be uninformative. Challenges including the consideration of intercurrent events, the difficulty in maintaining adequate completion rates, and considerable patient and trial burden from long-term, serial, patient-reported outcome measurements render time to deterioration a problematic approach for widespread use. For trials in which a comparative benefit in symptoms or function is an objective, an analysis at pre-specified relevant timepoints could be a better approach.

US Food and Drug Administration Analysis of Patient-Reported Diarrhea and Its Impact on Function and Quality of Life in Patients Receiving Treatment for Breast Cancer.

OBJECTIVES: Many trials conclude "no clinically meaningful detriment" to health-related quality of life (HRQL) or function between arms, even when notable differential toxicity is observed. Mean change from baseline analyses of function or HRQL can possibly obscure important change in subgroups experiencing symptomatic toxicity. We evaluate the impact of diarrhea, a key treatment arm toxicity, on patient-reported HRQL and functioning in clinical trials submitted to US Food and Drug Administration. METHODS: This study used 4 randomized, breast cancer trials (adjuvant to late-line metastatic) as case examples. Diarrhea, physical functioning (PF), and global health status and quality of life (GHS/QoL) from the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-C30 were analyzed at baseline and approximately 3 and 6 months. RESULTS: Generally, patients reporting very much diarrhea at months 3 and 6 had worse PF (9-19 points lower) and GHS/QoL (16-19 points lower) than patients reporting no diarrhea regardless of treatment arm. In the change from baseline analysis, patients reporting very much diarrhea also experienced a greater decrease in PF (6-13 points) and GHS/QoL (6-16 points) versus patients reporting no diarrhea in both arms. CONCLUSIONS: In trials with moderate to large differences in symptomatic toxicity by arm, reporting "no meaningful difference in functioning and HRQL between arms" based on mean change from baseline analysis is insufficient and may obscure important impacts on subgroups experiencing symptomatic adverse events. Additional exploratory analyses with simple data visualizations evaluating functioning or HRQL in patient subgroups experiencing expected symptomatic toxicities can further inform the safety and tolerability of an investigational agent.

Demystifying the estimand framework: a case study using patient-reported outcomes in oncology.

Patient-reported outcome (PRO) measures describe how a patient feels or functions and are increasingly being used in benefit-risk assessments in the development of cancer drugs. However, PRO research objectives are often ill-defined in clinical cancer trials, which can lead to misleading conclusions about patient experiences. The estimand framework is a structured approach to aligning a clinical trial objective with the study design, including endpoints and analysis. The estimand framework uses a multidisciplinary approach and can improve design, analysis, and interpretation of PRO results. On the basis of the International Council for Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use E9(R1) addendum, we provide an overview of the estimand framework intended for a multistakeholder audience. We apply the estimand framework to a hypothetical trial for breast cancer, using physical function to develop specific PRO research objectives. This Policy Review is not an endorsement of a specific study design or outcome; rather, it is meant to show the application of principles of the estimand framework to research study design and add to ongoing discussion. Use of the estimand framework to review medical products and label PROs in oncology can improve communication between stakeholders and ultimately provide a clearer interpretation of patient experience in the development of oncological drugs.

US Food and Drug Administration review of statistical analysis of patient-reported outcomes in lung cancer clinical trials approved between January, 2008, and December, 2017.

With the advent of patient-focused drug development, the US Food and Drug Administration (FDA) has redoubled its efforts to review patient-reported outcome (PRO) data in cancer trials submitted as part of a drug's marketing application. This Review aims to characterise the statistical analysis of PRO data from pivotal lung cancer trials submitted to support FDA drug approval between January, 2008, and December, 2017. For each trial and PRO instrument identified, we evaluated prespecified PRO concepts, statistical analysis, missing data and sensitivity analysis, instrument completion, and clinical relevance. Of the 37 pivotal lung cancer trials used to support FDA drug approval, 25 (68%) trials included PRO measures. The most common prespecified PRO concepts were cough, dyspnoea, and chest pain. At the trial level, the most common statistical analyses were descriptive (24 trials [96%]), followed by time-to-event analyses (19 trials [76%]), longitudinal analyses (12 trials [48%]), and basic inferential tests or general linear models (10 trials [40%]). Our findings indicate a wide variation in the analytic techniques and data presentation methods used, with very few trials reporting clear PRO research objectives and sensitivity analyses for PRO results. Our work further supports the need for focused research objectives to justify and to guide the analytic strategy of PROs to facilitate the interpretation of patient experience.

FDA Benefit-Risk Assessment of Osimertinib for the Treatment of Metastatic Non-Small Cell Lung Cancer Harboring Epidermal Growth Factor Receptor T790M Mutation.

On March 30, 2017, the U.S. Food and Drug Administration (FDA) approved osimertinib for the treatment of patients with metastatic, epidermal growth factor receptor (EGFR) T790M mutation-positive, non-small cell lung cancer (NSCLC), as detected by an FDA-approved test, whose disease has progressed following EGFR tyrosine kinase inhibitor (TKI) therapy. Approval was based on demonstration of a statistically significant difference in the primary endpoint of progression-free survival (PFS) when comparing osimertinib with chemotherapy in an international, multicenter, open-label, randomized trial (AURA3). In this confirmatory trial, which enrolled 419 patients, the PFS hazard ratio for osimertinib compared with chemotherapy per investigator assessment was 0.30 (95% confidence interval 0.23-0.41), p < .001, with median PFS of 10.1 months in the osimertinib arm and 4.4 months in the chemotherapy arm. Supportive efficacy data included PFS per blinded independent review committee demonstrating similar PFS results and an improved confirmed objective response rate per investigator assessment of 65% and 29%, with estimated median durations of response of 11.0 months and 4.2 months, in the osimertinib and chemotherapy arms, respectively. Patients received osimertinib 80 mg once daily and had a median duration of exposure of 8 months. The toxicity profile of osimertinib compared favorably with the profile of other approved EGFR TKIs and chemotherapy. The most common adverse drug reactions (>20%) in patients treated with osimertinib were diarrhea, rash, dry skin, nail toxicity, and fatigue. Herein, we review the benefit-risk assessment of osimertinib that led to regular approval, for patients with metastatic NSCLC harboring EGFR TKI whose disease has progressed on or after EGFR TKI therapy. IMPLICATIONS FOR PRACTICE: Osimertinib administered to metastatic non-small cell lung cancer (NSCLC) patients harboring an EGFR T790M mutation, who have progressed on or following EGFR TKI therapy, demonstrated a substantial improvement over platinum-based doublet chemotherapy as well as durable intracranial responses. The ability to test for the T790M mutation in plasma using the FDA-approved cobas EGFR Mutation Test v2 (Roche, Basel, Switzerland) identifies patients with NSCLC tumors not amenable to biopsy. Since a 40% false-negative rate has been observed with the circulating tumor DNA test, re-evaluation of the feasibility of tissue biopsy is recommended to identify patients with a false-negative plasma test result who may benefit from osimertinib.

Informing the Tolerability of Cancer Treatments Using Patient-Reported Outcome Measures: Summary of an FDA and Critical Path Institute Workshop.

The US Food and Drug Administration and the Critical Path Institute's Patient-Reported Outcome (PRO) Consortium convened a cosponsored workshop on the use of PRO measures to inform the assessment of safety and tolerability in cancer clinical trials. A broad array of international stakeholders involved in oncology drug development and PRO measurement science provided perspectives on the role of PRO measures to provide complementary clinical data on the symptomatic side effects of anticancer agents. Speakers and panelists explored the utility of information derived from existing and emerging PRO measures, focusing on the PRO version of the National Cancer Institute's Common Terminology Criteria for Adverse Events. Panelists and speakers discussed potential ways to improve the collection, analysis, and presentation of PRO data describing symptomatic adverse events to support drug development and better inform regulatory and treatment decisions. Workshop participants concluded the day with a discussion of possible approaches to the patient-reported assessment of an investigational drug's overall side effect burden as a potential clinical trial end point. The Food and Drug Administration reiterated its commitment to collaborate with international drug development stakeholders to identify rigorous methods to incorporate the patient perspective into the development of cancer therapeutics.

Missing data handling in non-inferiority and equivalence trials: A systematic review.

BACKGROUND: Non-inferiority (NI) and equivalence clinical trials test whether a new treatment is therapeutically no worse than, or equivalent to, an existing standard of care. Missing data in clinical trials have been shown to reduce statistical power and potentially bias estimates of effect size; however, in NI and equivalence trials, they present additional issues. For instance, they may decrease sensitivity to differences between treatment groups and bias toward the alternative hypothesis of NI (or equivalence). AIMS: Our primary aim was to review the extent of and methods for handling missing data (model-based methods, single imputation, multiple imputation, complete case), the analysis sets used (Intention-To-Treat, Per-Protocol, or both), and whether sensitivity analyses were used to explore departures from assumptions about the missing data. METHODS: We conducted a systematic review of NI and equivalence trials published between May 2015 and April 2016 by searching the PubMed database. Articles were reviewed primarily by 2 reviewers, with 6 articles reviewed by both reviewers to establish consensus. RESULTS: Of 109 selected articles, 93% reported some missing data in the primary outcome. Among those, 50% reported complete case analysis, and 28% reported single imputation approaches for handling missing data. Only 32% reported conducting analyses of both intention-to-treat and per-protocol populations. Only 11% conducted any sensitivity analyses to test assumptions with respect to missing data. CONCLUSION: Missing data are common in NI and equivalence trials, and they are often handled by methods which may bias estimates and lead to incorrect conclusions.

A pattern-mixture model approach for handling missing continuous outcome data in longitudinal cluster randomized trials.

We extend the pattern-mixture approach to handle missing continuous outcome data in longitudinal cluster randomized trials, which randomize groups of individuals to treatment arms, rather than the individuals themselves. Individuals who drop out at the same time point are grouped into the same dropout pattern. We approach extrapolation of the pattern-mixture model by applying multilevel multiple imputation, which imputes missing values while appropriately accounting for the hierarchical data structure found in cluster randomized trials. To assess parameters of interest under various missing data assumptions, imputed values are multiplied by a sensitivity parameter, k, which increases or decreases imputed values. Using simulated data, we show that estimates of parameters of interest can vary widely under differing missing data assumptions. We conduct a sensitivity analysis using real data from a cluster randomized trial by increasing k until the treatment effect inference changes. By performing a sensitivity analysis for missing data, researchers can assess whether certain missing data assumptions are reasonable for their cluster randomized trial.

Impact of caregiver activities and social supports on multidimensional caregiver burden: analyses from nationally-representative surveys of cancer patients and their caregivers.

PURPOSE: Informal caregivers of individuals with cancer may experience substantial burdens. To develop interventions to support these caregivers, it is crucial to quantify and understand the domains of burdens potentially experienced by caregivers and factors contributing to each domain. METHODS: Using data from two national surveys, the National Survey of Caregiving (NSOC) linked to the National Health and Aging Trends Survey (NHATS), we identified all participants in the NHATS diagnosed with cancer who had a caregiver participating in the NSOC. Guided by a theoretical model, twenty-two items in the NSOC related to caregiver health, mood and outlook were included in factor analysis to develop scales capturing domains of burden. Multivariable regression analyses examined whether activities performed by caregivers and supports for caregivers were associated with these burden scales. RESULTS: Analysis of responses from 373 caregivers of cancer patients identified three scales: emotional burden; psychological burden; and relationship with the patient. Providing assistance managing medical care was associated with increased emotional and psychological burden, while assistance with non-medical issues increased psychological burden and worsened relationships with patients. Caregiver provision of direct patient care activities was also associated with increased burden but improved relationships with patients. Use of caregiver supports showed mixed associations with burden. CONCLUSIONS: Using a nationally-representative sample of cancer patients and their caregivers and brief publicly-available survey questions, we present three scales addressing different aspects of caregiver burden that are responsive to caregiver activities and social supports. This may assist in developing and evaluating intervention to decrease caregiver burden.

Generalized estimating equations in cluster randomized trials with a small number of clusters: Review of practice and simulation study.

BACKGROUND/AIMS: Generalized estimating equations are a common modeling approach used in cluster randomized trials to account for within-cluster correlation. It is well known that the sandwich variance estimator is biased when the number of clusters is small (≤40), resulting in an inflated type I error rate. Various bias correction methods have been proposed in the statistical literature, but how adequately they are utilized in current practice for cluster randomized trials is not clear. The aim of this study is to evaluate the use of generalized estimating equation bias correction methods in recently published cluster randomized trials and demonstrate the necessity of such methods when the number of clusters is small. METHODS: Review of cluster randomized trials published between August 2013 and July 2014 and using generalized estimating equations for their primary analyses. Two independent reviewers collected data from each study using a standardized, pre-piloted data extraction template. A two-arm cluster randomized trial was simulated under various scenarios to show the potential effect of a small number of clusters on type I error rate when estimating the treatment effect. The nominal level was set at 0.05 for the simulation study. RESULTS: Of the 51 included trials, 28 (54.9%) analyzed 40 or fewer clusters with a minimum of four total clusters. Of these 28 trials, only one trial used a bias correction method for generalized estimating equations. The simulation study showed that with four clusters, the type I error rate ranged between 0.43 and 0.47. Even though type I error rate moved closer to the nominal level as the number of clusters increases, it still ranged between 0.06 and 0.07 with 40 clusters. CONCLUSIONS: Our results showed that statistical issues arising from small number of clusters in generalized estimating equations is currently inadequately handled in cluster randomized trials. Potential for type I error inflation could be very high when the sandwich estimator is used without bias correction.

Feasibility of Cognitively-Based Compassion Training (CBCT) for breast cancer survivors: a randomized, wait list controlled pilot study.

PURPOSE: This study assessed the feasibility of a meditation-based program called Cognitively-Based Compassion Training (CBCT) with breast cancer survivors. Enrollment and participant satisfaction with a novel intervention, adherence to program requirements, and differences between the intervention group and wait list controls on self-report measures were also assessed. Additionally, cortisol, a stress-related endocrine biomarker, was assessed. METHODS: Participants (n = 33) were randomly assigned to CBCT or the wait list. CBCT provided eight weekly, 2-h classes and a "booster" CBCT session 4 weeks later. CBCT participants were expected to attend classes and meditate between classes at least three times per week. Pre-/post-intervention and follow-up questionnaires measured symptom change (depression, intrusive thoughts, perceived stress, fear of cancer recurrence, fatigue/vitality, loneliness, and quality of life). Saliva samples were collected at the same periods to assess the slope of diurnal cortisol activity. RESULTS: Enrollment, class attendance, home practice time, and patient satisfaction exceeded expectations. Compared to controls, post-intervention, the CBCT group showed suggestions of significant improvements in depression, avoidance of intrusive thoughts, functional impairment associated with fear of recurrence, mindfulness, and vitality/fatigue. At follow-up, less perceived stress and higher mindfulness were also significant in the CBCT group. No significant changes were observed on any other measure including diurnal cortisol activity. CONCLUSIONS: Within the limits of a pilot feasibility study, results suggest that CBCT is a feasible and highly satisfactory intervention potentially beneficial for the psychological well-being of breast cancer survivors. However, more comprehensive trials are needed to provide systematic evidence. RELEVANCE: CBCT may be very beneficial for improving depression and enhancing well-being during breast cancer survivorship.

Handling missing data in RCTs; a review of the top medical journals.

BACKGROUND: Missing outcome data is a threat to the validity of treatment effect estimates in randomized controlled trials. We aimed to evaluate the extent, handling, and sensitivity analysis of missing data and intention-to-treat (ITT) analysis of randomized controlled trials (RCTs) in top tier medical journals, and compare our findings with previous reviews related to missing data and ITT in RCTs. METHODS: Review of RCTs published between July and December 2013 in the BMJ, JAMA, Lancet, and New England Journal of Medicine, excluding cluster randomized trials and trials whose primary outcome was survival. RESULTS: Of the 77 identified eligible articles, 73 (95%) reported some missing outcome data. The median percentage of participants with a missing outcome was 9% (range 0 - 70%). The most commonly used method to handle missing data in the primary analysis was complete case analysis (33, 45%), while 20 (27%) performed simple imputation, 15 (19%) used model based methods, and 6 (8%) used multiple imputation. 27 (35%) trials with missing data reported a sensitivity analysis. However, most did not alter the assumptions of missing data from the primary analysis. Reports of ITT or modified ITT were found in 52 (85%) trials, with 21 (40%) of them including all randomized participants. A comparison to a review of trials reported in 2001 showed that missing data rates and approaches are similar, but the use of the term ITT has increased, as has the report of sensitivity analysis. CONCLUSIONS: Missing outcome data continues to be a common problem in RCTs. Definitions of the ITT approach remain inconsistent across trials. A large gap is apparent between statistical methods research related to missing data and use of these methods in application settings, including RCTs in top medical journals.

Equipoise Lost? Trial Conduct Challenges in an Era of Breakthrough Therapies.

FDA Oncology Center's @Falleh_Fallah and colleagues discuss loss of equipoise and other trial conduct challenges in an era of breakthrough therapies - via @JCO_ASCO.

False-Positive Circulating Tumor DNA Results Do Not Explain Lack of Efficacy for PARP Inhibitors in Patients With Castration-Resistant Prostate Cancer Harboring ATM and CHEK2 Mutations.

False-positive ctDNA results do not explain lack of efficacy for PARPi in patients with ATMm and CHEK2m CRPC.

FDA Approval Summary: Belzutifan for Patients with Advanced Renal Cell Carcinoma.

On December 14, 2023, the United States Food and Drug Administration (FDA) approved belzutifan (Welireg, Merck & Co., Inc.) for patients with advanced renal cell carcinoma (RCC) following a programmed death receptor-1 or programmed death-ligand 1 (PD-1/PD-L1) inhibitor and a vascular endothelial growth factor tyrosine kinase inhibitor (VEGF-TKI). FDA granted traditional approval based on LITESPARK-005 (NCT04195750), an open-label, randomized, head-to-head trial of 746 patients with advanced RCC that progressed following both a PD-1/PD-L1 inhibitor and a VEGF-TKI. Patients were randomized (1:1) to receive belzutifan or everolimus. The primary endpoints were progression-free survival (PFS) assessed by blinded independent central review (BICR) and overall survival (OS). A statistically significant improvement in PFS was demonstrated for belzutifan compared with everolimus [hazard ratio (HR)=0.75 (95% CI: 0.63, 0.90); 1-sided p-value=0.0008]. Kaplan-Meier curves reflected non-proportional hazards with similar median PFS estimates of 5.6 months (95% CI: 3.9, 7.0) in the belzutifan arm and 5.6 months (95% CI: 4.8, 5.8) in the everolimus arm. While not reaching full maturity, OS results appeared to show a favorable trend in the belzutifan arm compared to everolimus [HR=0.88 (95% CI: 0.73, 1.07)]. The confirmed objective response rate by BICR was 22% and 3.6% in belzutifan and everolimus arms, respectively. Observed toxicities differed between treatment arms, but drug discontinuations and interruptions due to treatment-emergent adverse events were lower on the belzutifan arm compared to the everolimus arm, and a descriptive analysis of patient-reported symptom and functional outcomes was suggestive of favorable tolerability for belzutifan compared to everolimus.

FDA Approval Summary: Enfortumab Vedotin Plus Pembrolizumab for Locally Advanced or Metastatic Urothelial Carcinoma.

On December 15, 2023, the FDA granted traditional approval to enfortumab vedotin-ejfv plus pembrolizumab (EV + Pembro) for patients with locally advanced or metastatic urothelial carcinoma (la/mUC). Substantial evidence of effectiveness was obtained from EV-302/KEYNOTE-A39 (NCT04223856), an open-label, randomized, trial evaluating EV + Pembro versus cisplatin or carboplatin plus gemcitabine (Plat + Gem) in patients with previously untreated la/mUC. A total of 886 patients were randomized (1:1) to receive EV 1.25 mg/kg intravenously on days 1 and 8 of each 21-day cycle until disease progression or unacceptable toxicity plus pembrolizumab 200 mg intravenously on day 1 of each 21-day cycle for up to 35 cycles, or Plat + Gem for up to 6 cycles. Dual primary endpoints were progression-free survival (PFS) determined by blinded independent central review and overall survival (OS). Median PFS was 12.5 months (95% CI: 10.4, 16.6) in the EV + Pembro arm and 6.3 months (95% CI: 6.2, 6.5) in the Plat + Gem arm (HR 0.450 [95% CI: 0.377, 0.538]; p-value < 0.0001). Median OS was 31.5 months (95% CI: 25.4, NE) in the EV + Pembro arm and 16.1 months (95% CI: 13.9, 18.3) in the Plat + Gem arm (HR 0.468 [95% CI: 0.376, 0.582]; p-value < 0.0001). The safety profile of EV + pembrolizumab was similar to that observed in EV-103/KEYNOTE-869 in cisplatin-ineligible patients with la/mUC. This article summarizes the data and the FDA thought process supporting traditional approval of EV + pembrolizumab, as well as additional exploratory analyses conducted by FDA.

Integrating 4 methods to evaluate physical function in patients with cancer (In4M): protocol for a prospective cohort study.

INTRODUCTION: Accurate, patient-centred evaluation of physical function in patients with cancer can provide important information on the functional impacts experienced by patients both from the disease and its treatment. Increasingly, digital health technology is facilitating and providing new ways to measure symptoms and function. There is a need to characterise the longitudinal measurement characteristics of physical function assessments, including clinician-reported outcome, patient-reported ported outcome (PRO), performance outcome tests and wearable data, to inform regulatory and clinical decision-making in cancer clinical trials and oncology practice. METHODS AND ANALYSIS: In this prospective study, we are enrolling 200 English-speaking and/or Spanish-speaking patients with breast cancer or lymphoma seen at Mayo Clinic or Yale University who will receive intravenous cytotoxic chemotherapy. Physical function assessments will be obtained longitudinally using multiple assessment modalities. Participants will be followed for 9 months using a patient-centred health data aggregating platform that consolidates study questionnaires, electronic health record data, and activity and sleep data from a wearable sensor. Data analysis will focus on understanding variability, sensitivity and meaningful changes across the included physical function assessments and evaluating their relationship to key clinical outcomes. Additionally, the feasibility of multimodal physical function data collection in real-world patients with breast cancer or lymphoma will be assessed, as will patient impressions of the usability and acceptability of the wearable sensor, data aggregation platform and PROs. ETHICS AND DISSEMINATION: This study has received approval from IRBs at Mayo Clinic, Yale University and the US Food and Drug Administration. Results will be made available to participants, funders, the research community and the public. TRIAL REGISTRATION NUMBER: NCT05214144; Pre-results.

US Food and Drug Administration Approval Summary: Elacestrant for Estrogen Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative, ESR1-Mutated Advanced or Metastatic Breast Cancer.

PURPOSE: The US Food and Drug Administration (FDA) approved elacestrant for the treatment of postmenopausal women or adult men with estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2-), estrogen receptor 1 (ESR1)-mutated advanced or metastatic breast cancer with disease progression after at least one line of endocrine therapy (ET). PATIENTS AND METHODS: Approval was based on EMERALD (Study RAD1901-308), a randomized, open-label, active-controlled, multicenter trial in 478 patients with ER+, HER2- advanced or metastatic breast cancer, including 228 patients with ESR1 mutations. Patients were randomly assigned (1:1) to receive either elacestrant 345 mg orally once daily (n = 239) or investigator's choice of ET (n = 239). RESULTS: In the ESR1-mut subgroup, EMERALD demonstrated a statistically significant improvement in progression-free survival (PFS) by blinded independent central review assessment (n = 228; hazard ratio [HR], 0.55 [95% CI, 0.39 to 0.77]; P value = .0005). Although the overall survival (OS) end point was not met, there was no trend toward a potential OS detriment (HR, 0.90 [95% CI, 0.63 to 1.30]) in the ESR1-mut subgroup. PFS also reached statistical significance in the intention-to-treat population (ITT, N = 478; HR, 0.70 [95% CI, 0.55 to 0.88]; P value = .0018). However, improvement in PFS in the ITT population was primarily attributed to results from patients in the ESR1-mut subgroup. More patients who received elacestrant experienced nausea, vomiting, and dyslipidemia. CONCLUSION: The approval of elacestrant in ER+, HER2- advanced or metastatic breast cancer was restricted to patients with ESR1 mutations. Benefit-risk assessment in the ESR1-mut subgroup was favorable on the basis of a statistically significant improvement in PFS in the context of an acceptable safety profile including no evidence of a potential detriment in OS. By contrast, the benefit-risk assessment in patients without ESR1 mutations was not favorable. Elacestrant is the first oral estrogen receptor antagonist to receive FDA approval for patients with ESR1 mutations.

FDA Approval Summary: Olaparib in Combination With Abiraterone for Treatment of Patients With BRCA-Mutated Metastatic Castration-Resistant Prostate Cancer.

PURPOSE: This article summarizes the US Food and Drug Administration (FDA) review of the data leading to approval of olaparib plus abiraterone for the treatment of patients with deleterious or suspected deleterious BRCA-mutated (BRCAm) metastatic castration-resistant prostate cancer (mCRPC), as determined by an FDA-approved companion diagnostic test. PATIENTS AND METHODS: Approval was based on the results from PROpel, a double-blind trial that randomly assigned 796 patients with mCRPC to abiraterone plus prednisone or prednisolone with either olaparib or placebo. The primary end point was radiographic progression-free survival (rPFS) per investigator assessment. RESULTS: There was a statistically significant improvement in rPFS for olaparib plus abiraterone versus placebo plus abiraterone, with a median rPFS of 25 versus 17 months and a hazard ratio (HR) of 0.66 (95% CI, 0.54 to 0.81) in the intention-to-treat population. In an exploratory analysis of the subgroup of 85 patients with BRCAm mCRPC, the HR for rPFS was 0.24 (95% CI, 0.12 to 0.45) and the HR for overall survival (OS) was 0.30 (95% CI, 0.15 to 0.59). In an exploratory analysis of the subgroup of 711 patients without an identified BRCA mutation, the HR for rPFS was 0.77 (95% CI, 0.63 to 0.96) and the HR for OS was 0.92 (95% CI, 0.74 to 1.14). Adding olaparib to abiraterone resulted in increased toxicity, including anemia requiring transfusion in 18% of patients. CONCLUSION: In patients with mCRPC, efficacy of the combination of olaparib plus abiraterone was primarily attributed to the treatment effect in the BRCAm subgroup, the indicated population for the approval. For patients without BRCAm, the FDA determined that the modest rPFS improvement, combined with clinically significant toxicities, did not demonstrate a favorable risk/benefit assessment.