Using Bayesian statistics in confirmatory clinical trials in the regulatory setting: a tutorial review.

Bayesian statistics plays a pivotal role in advancing medical science by enabling healthcare companies, regulators, and stakeholders to assess the safety and efficacy of new treatments, interventions, and medical procedures. The Bayesian framework offers a unique advantage over the classical framework, especially when incorporating prior information into a new trial with quality external data, such as historical data or another source of co-data. In recent years, there has been a significant increase in regulatory submissions using Bayesian statistics due to its flexibility and ability to provide valuable insights for decision-making, addressing the modern complexity of clinical trials where frequentist trials are inadequate. For regulatory submissions, companies often need to consider the frequentist operating characteristics of the Bayesian analysis strategy, regardless of the design complexity. In particular, the focus is on the frequentist type I error rate and power for all realistic alternatives. This tutorial review aims to provide a comprehensive overview of the use of Bayesian statistics in sample size determination, control of type I error rate, multiplicity adjustments, external data borrowing, etc., in the regulatory environment of clinical trials. Fundamental concepts of Bayesian sample size determination and illustrative examples are provided to serve as a valuable resource for researchers, clinicians, and statisticians seeking to develop more complex and innovative designs.

Reporting of interventional clinical trial results in an academic center: a survey of completed studies.

BACKGROUND: The dissemination of clinical trial results is an important scientific and ethical endeavour. This survey of completed interventional studies in a French academic center describes their reporting status. METHODS: We explored all interventional studies sponsored by Rennes University Hospital identified on the French Open Science Monitor which tracks trials registered on EUCTR or clinicaltrials.gov, and provides an automatic assessment of the reporting of results. For each study, we ascertained the actual reporting of results using systematic searches on the hospital internal database, bibliographic databases (Google Scholar, PubMed), and by contacting all principal investigators (PIs). We describe several features (including total budget and numbers of trial participants) of the studies that did not report any results. RESULTS: The French Open Science Monitor identified 93 interventional studies, among which 10 (11%) reported results. In contrast, our survey identified 36 studies (39%) reporting primary analysis results and an additional 18 (19%) reporting results for secondary analyses (without results for their primary analysis). The overall budget for studies that did not report any results was estimated to be €5,051,253 for a total of 6,735 trial participants. The most frequent reasons for the absence of results reported by PIs were lack of time for 18 (42%), and logistic difficulties (e.g. delay in obtaining results or another blocking factor) for 12 (28%). An association was found between non-publication and negative results (adjusted Odds Ratio = 4.70, 95% Confidence Interval [1.67;14.11]). CONCLUSIONS: Even allowing for the fact that automatic searches underestimate the number of studies with published results, the level of reporting was disappointingly low. This amounts to a waste of trial participants' implication and money. Corrective actions are needed. TRIAL REGISTRATION: https://osf.io/q5hcs.

Comparison of revision rates and epidemiological data of a single total knee arthroplasty system of different designs (cruciate retaining, posterior stabilized, mobile bearing, and fixed bearing): a meta-analysis and systematic review of clinical trials and national arthroplasty registries.

BACKGROUND: This study aimed to meta-analyze epidemiological data, revision rates, and incidences of different designs of a single Total Knee Arthroplasty System and compare these factors across different countries. METHODS: A systematic review was conducted on clinical studies and arthroplasty registries of ATTUNE TKA from 1999 to 2020. The main endpoints analyzed were revision rates and epidemiological data. RESULTS: The average age of patients was 67.8 years, with a gender distribution of 60% female and 40% male. The pooled average BMI was 29.4 kg/m2. Eight clinical studies showed a pooled revision rate per 100 observed CY of 0.5 (n = 1343 cases). Cumulative revision rates after 1, 3, and 5 years varied among registries, with the Swiss registry having the highest revision data (after 5 years: 6.3%) and the American registry having the lowest revision data (after 5 years: 1.7%). A comparison of the revision rates of mobile bearing and fixed bearing (41,200 cases) as well as cruciate retaining and posterior stabilized (n = 123,361 cases) showed no significant advantage in the first 5 years after implantation. CONCLUSION: In conclusion, pooled data from 41,200 cases of TKA with a single Total Knee Arthroplasty System in two arthroplasty registries revealed that there was no significant difference in revision rates between the mobile bearing and fixed bearing design within the first 5 years after implantation. In addition, a comparison of the revision rates in n = 123,361 cases showed no significant advantage for cruciate retaining or posterior stabilized in the first 5 years after implantation.

Toward Equitable Precision Oncology: Monitoring Racial and Ethnic Inclusion in Genomics and Clinical Trials.

PURPOSE: Ethnic diversity in cancer research is crucial as race/ethnicity influences cancer incidence, survival, drug response, molecular pathways, and epigenetic phenomena. In 2018, we began a project to examine racial/ethnic diversity in cancer research, with a commitment to review these disparities every 4 years. This report is our second assessment, detailing the present state of racial/ethnic diversity in cancer genomics and clinical trials. METHODS: To study racial/ethnic inclusion in cancer genomics, we extracted ethnic records from all data sets available at cBioPortal (n = 125,128 patients) and cancer-related genome-wide association studies (n = 28,011,282 patients) between 2018 and 2022. Concerning clinical trials, we selected studies related to breast cancer (n = 125,518 patients, 181 studies), lung cancer (n = 34,329 patients, 119 studies), and colorectal cancer (n = 40,808 patients, 105 studies). RESULTS: In cancer genomics (N = 28,136,410), 3% of individuals lack racial/ethnic registries; tumor samples were collected predominantly from White patients (89.14%), followed by Asian (7%), African American (0.55%), and Hispanic (0.21%) patients and other populations (0.1%). In clinical trials (N = 200,655), data on race/ethnicity are missing for 60.14% of the participants; for individuals whose race/ethnicity was recorded, most were characterized as White (28.33%), followed by Asian (7.64%), African (1.79), other ethnicities (1.37), and Hispanic (0.73). Racial/ethnic representation significantly deviates from global ethnic proportions (P ≤ .001) across all data sets, with White patients outnumbering other ethnic groups by a factor of approximately 4-6. CONCLUSION: Our second update on racial/ethnic representation in cancer research highlights the persistent overrepresentation of White populations in cancer genomics and a notable absence of racial/ethnic information across clinical trials. To ensure more equitable and effective precision oncology, future efforts should address the reasons behind the insufficient representation of ethnically diverse populations in cancer research.

Are orthopedic clinical trials representative? An analysis of race and ethnicity reported in clinical trials between 2007 and 2022 : Running title: representation of clinical trials in orthopedic surgery.

INTRODUCTION: Prior studies investigating the racial and ethnic representation of orthopedic trial participants have found low rates of reporting, but these studies are dated due to the passing of the National Institutes of Health Final Rule in 2017 requiring the reporting of racial and ethnic data among clinical trials. Therefore, we evaluated the representativeness of orthopedic clinical trials before and after the Final Rule. METHODS: A cross-sectional survey of orthopaedic clinical trials registered at ClinicalTrials.gov between October 1, 2007 and May 20, 2023 was conducted. After identifying and screening 23,752 clinical trials, 1564 trials were included in the analysis. Trials started before the implementation of the Final Rule on January 18, 2017 were grouped and compared to trials that began after. Odds ratios (OR) were utilized to identify trial characteristics associated with reporting race/ethnicity data. One-proportion z tests compared the representation of each racial and ethnic category to the 2020 United States Census. RESULTS: In total, 34% (544 of 1564) of orthopedic clinical trials evaluated reported the race of participants, while 28% (438 of 1564) reported ethnicity. Trials registered after the Final Rule were more likely to report racial (OR: 5.15, 95%CI: 3.72-7.13, p < 0.001) and ethnic (OR: 3.23, 95%CI: 2.41-4.33, p < 0.001) representation of participants. Compared with the distribution of race and ethnicity reported by the United States 2020 Census, orthopedic trials had 16.6% more White participants (95% CI 16.4%, 16.8%; p < 0.001), 3.2% fewer Black participants (95%CI 3.1%, 3.3%; p < 0.001), and 5.7% fewer Hispanic/Latino participants (95%CI 5.2%, 6.2%; p < 0.001). Trials with enrollment sizes over 100 participants were also more likely to report race and ethnicity, with odds increasing with increased sample size. CONCLUSIONS: The Final Rule marginally improved the reporting of race and ethnicity in orthopedic clinical trials, and underrepresentation of Black or African American, Multiracial, and Hispanic populations persists. LEVEL OF EVIDENCE: III.

Diversity of US participants in AstraZeneca-sponsored clinical trials.

BACKGROUND: To develop medicines that are safe and efficacious to all patients, clinical trials must enroll appropriate target populations, but imbalances related to race, ethnicity and sex have been reported. A comprehensive analysis and improvement in understanding representativeness of patient enrollment in industry-sponsored trials are key public health needs. METHODS: We assessed race/ethnicity and sex representation in AstraZeneca (AZ)-sponsored clinical trials in the United States (US) from 2010 to 2022, compared with the 2019 US Census. RESULTS: In total, 246 trials representing 95,372 patients with complete race/ethnicity and sex records were analyzed. The proportions of different race/ethnicity subgroups in AZ-sponsored clinical trials and the US Census were similar (White: 69.5% vs 60.1%, Black or African American: 13.3% vs 12.5%, Asian: 1.8% vs 5.8%, Hispanic: 14.4% vs 18.5%). We also observed parity in the proportions of males and females between AZ clinical trials and US Census (males: 52.4% vs 49.2%, females: 47.6% vs 50.8%). Comparisons of four distinct therapy areas within AZ (Respiratory and Immunology [R&I]; Cardiovascular, Renal, and Metabolism [CVRM]; Solid Tumors; and Hematological Malignancies), including by trial phases, revealed greater variability, with proportions observed above and below US Census levels. CONCLUSION: This analysis provides the first detailed insights into the representativeness of AZ trials. Overall, the proportions of different race/ethnicity and sex subgroups in AZ-sponsored clinical trials were broadly aligned with the US Census. We outline some of AZ's planned health equity initiatives that are intended to continue to improve equitable patient enrollment.

Neighborhood socioeconomic disadvantage measures in rehabilitation clinical trials: Lessons learned in recruitment.

PURPOSE: The Area Deprivation Index (ADI) measures the relative disadvantage of an individual or social network using US Census indicators. Although a strong re-hospitalization predictor, ADI has not been routinely incorporated into rehabilitation research. The purposes of this paper are to examine the use of ADI related to study recruitment, association with carepartner psychosocial factors, and recruitment strategies to increase participant diversity. METHODS: Descriptive analysis of baseline data from a pilot stroke carepartner-integrated therapy trial. Participants were 32 carepartners (N = 32; 62.5 % female; mean age 57.8 ± 13.0 years) and stroke survivors (mean age (60.6 ± 14.2) residing in an urban setting. Measures included ADI, Bakas Caregiver Outcome Scale, Caregiver Strain Index, and Family Assessment Device. RESULTS: Most carepartners were Non-Hispanic White participants (61.3 %), part or fully employed (43 %), with >$50,000 (67.7 %) income, and all had some college education. Most stroke survivors were Non-Hispanic White participants (56.3 %) with some college (81.3 %). Median ADI state deciles were 3.0 (interquartile range 1.5-5, range 1-9), and mean national percentiles were 41.7 ± 23.5 with only 6.3 % of participants from the most disadvantaged neighborhoods. For the more disadvantaged half of the state deciles, the majority were Black or Asian participants. No ADI and carepartner factors were statistically related. CONCLUSIONS: The use of ADI data highlighted a recruitment gap in this stroke study, lacking the inclusivity of participants from disadvantaged neighborhoods and with lower education. Using social determinants of health indicators to identify underrepresented neighborhoods may inform recruitment methods to target marginalized populations and broaden the generalizability of clinical trials.

Disparities in clinical trial participation in ovarian cancer: A real-world analysis.

BACKGROUND: Significant disparities exist in clinical trial participation in non-gynecologic cancers, but little is known about disparities in ovarian cancer trial participation. Our objective was to examine patient, sociodemographic (race/ethnicity, insurance), cancer, and health system factors associated with clinical trial participation in ovarian cancer. METHODS: We conducted a retrospective cohort study of patients with epithelial ovarian cancer diagnosed from 2011 to 2021, using a real-world electronic health record derived database, representing around 800 sites of care in US academic and community practices. We used multivariable Poisson regression modeling to analyze the association of ever participating in an ovarian cancer clinical drug trial with patient, sociodemographic, health system, and cancer factors. RESULTS: Of the 7540 patients with ovarian cancer, 5.0% (95% CI 4.5-5.5) ever participated in a clinical drug trial. Patients of Hispanic or Latino ethnicity were 71% less likely to participate in clinical trials (RR 0.29, 95% CI 0.13-0.61) than non-Hispanic patients, and patients whose race was unknown or other than Black or White were 40% less likely to participate in clinical trials (RR 0.68, 95% CI 0.52-0.89). Patients who had Medicaid insurance were 51% less likely (RR 0.49, 95% CI 0.28-0.87) and those with Medicare were 32% (RR 0.48-0.97) less likely to participate in clinical trials than privately-insured patients. CONCLUSION: In this national cohort study, only 5% of patients with ovarian cancer participated in clinical drug trials. Interventions are needed to decrease race, ethnicity, and insurance disparities in clinical trial participation.

Differential patient travel distance and time to psoriasis clinical trial sites.

Considering the known disparities in racial representation in psoriasis clinical trials, this study sought to characterize travel distance and time to reach a psoriasis clinical trial site as a potential barrier to trial participation for multiple demographic and geographic variables. We determined travel distance and time from every census tract population center in the United States to the nearest psoriasis clinical trial site using ArcGIS and linked travel estimates to demographic characteristics in each census tract based on 2020 American Community Survey. The average distance and time traveled to reach a psoriasis clinical trial site nationally were 45.6 miles and 51.8 min, respectively. Urban residence and Northeast location had significantly lower travel distance and time relative to their geographic counterparts. Travel burden was significantly greater among Native American and Black races, individuals without college education and Veterans Affairs beneficiaries relative to their counterparts. These findings reveal disparate access regarding rurality, race, education and insurance type, which may encourage investigators to increase travel funding for underrepresented groups and diversity recruitment efforts to promote access to psoriasis clinical trials.

Eligibility criteria and enrollment of a diverse racial and ethnic population in multiple myeloma clinical trials.

The narrow eligibility criteria may contribute to the underrepresentation of racial and ethnic subgroups in cancer clinical trials. We conducted a retrospective pooled analysis of multicenter global clinical trials submitted to the US Food and Drug Administration between 2006 and 2019 to support the approval of the use of multiple myeloma (MM) therapies that analyze the rates and reasons for trial ineligibility based on race and ethnicity in MM clinical trials. Race and ethnicity were coded per Office of Management and Budget standards. Patients flagged as having screen failures were identified as ineligible. Ineligibility rates were calculated as the percentage of patients who were ineligible compared with the screened population within the respective racial and ethnic subgroups. Trial eligibility criteria were grouped into specific categories to analyze the reasons for trial ineligibility. Black patients (24%) and other (23%) race subgroups had higher ineligibility rates than White patients (17%). The Asian race had the lowest ineligibility rate (12%) among all racial subgroups. Failure to meet the hematologic laboratory criteria (19%) and treatment-related criteria (17%) were the most common reasons for ineligibility among Black patients and were more common in Black patients than in other races. Failure to meet disease-related criteria was the most common reason for ineligibility among White (28%) and Asian (29%) participants. Our analysis indicates that specific eligibility criteria may contribute to enrollment disparities for racial and ethnic subgroups in MM clinical trials. However, the small number of screened patients in the underrepresented racial and ethnic subgroups limits definitive conclusions.

Racial and ethnic underrepresentation in dermatology clinical trials.

BACKGROUND: Including participants of diverse racial and ethnic populations in clinical trials is important to reduce disparities and promote health care equity. OBJECTIVE: To evaluate racial and ethnic representation in dermatology clinical trials. METHODS: Participant data from dermatology trials completed in the United States from 2017 to 2021 from ClinicalTrials.gov were compared to census data to determine if minority groups were represented at rates that reflect population demographics. Participation was compared with prevalence rates for the most underrepresented racial group. RESULTS: Of 246 trials that met inclusion criteria, 87.4% (215) reported racial data. Compared to census data, Black/African American, American Indian/Alaskan Native, and 2 or more races were underrepresented. Hispanic or Latinos were an underrepresented ethnic group. LIMITATIONS: The search was limited to ClinicalTrials.gov registered studies that fell within search parameters. Race reporting methods were not specified. Detailed analysis was only performed for the most underrepresented racial group. CONCLUSION: Certain minority groups were underrepresented in dermatology trials. Black/African Americans were most underrepresented and underrepresented even when accounting for prevalence rates. Trial representation that accurately reflects population demographics and subgroup prevalence rates can help reduce health inequity, improve clinical understanding, and enhance treatment access for the growing diverse population.

A scoping review on patient heterogeneity in economic evaluations of precision medicine based on basket trials.

INTRODUCTION: Considerable challenges in the economic evaluation of precision medicines have been mentioned in previous studies. However, they have not addressed how an economic assessment would be conducted based on basket trials (novel studies for evaluation of precision medicine effects) in which the included populations have specific biomarkers and various cancers. Since basket trial populations have remarkable heterogeneity, this study aims to investigate the concept of heterogeneity and specific method(s) for considering it in economic evaluations through guidelines and studies that could be applicable in economic evaluation based on basket trials. AREA COVERED: We searched PubMed, Web of Science, Scopus, Google Scholar, and Google to find studies and pharmacoeconomics guidelines. The inclusion criteria included subjects of patient heterogeneity and suggested explicit method(s). Thirty-nine guidelines and 43 studies were included and evaluated. None of these materials mentioned disease types in a target population as a factor causing heterogeneity. Moreover, in economic evaluations, patient heterogeneity has been considered with four general approaches subgroup analysis, individual-based models, sensitivity analysis, and regression models. EXPERT OPINION: Type of disease is not considered a contributing factor in population heterogeneity, and the probable appropriate method for this issue could be individual-based models.

Association of Remote Technology Use and Other Decentralization Tools With Patient Likelihood to Enroll in Cancer Clinical Trials.

Importance: Logistical challenges such as travel time and distance to a clinical trial site can be a barrier to patient participation. The association of remote technology use and other decentralization tools that can reduce these barriers with likelihood to enroll in cancer trials is not well understood. Objective: To assess the association of remote technology and other decentralization tools used to reduce participation-related time and travel with the likelihood to enroll in cancer clinical trials. Design, Setting, and Participants: Between July 6 and September 8, 2021, a 41-question, cross-sectional, internet-based survey was administered to patients with cancer and survivors of cancer in the US who had been diagnosed with or treated for cancer in the past 7 years. Main Outcomes and Measures: Increase in self-reported likelihood to enroll in cancer clinical trials that use remote technology and other decentralization tools to decrease the need for travel to the trial site. Results: There were 1183 survey respondents, with a mean (SD) age of 58.2 (12.5) years. Respondents self-reported their gender, race and ethnicity, cancer type, and treatment status. Of the 1183 respondents, 848 (72%) were female, 296 (25%) were male, 8 (1%) were other/nonbinary, and 31 (3%) declined to answer. With regard to race, 28 respondents (3%) were American Indian or Alaska Native, 25 (2%) were Asian, 234 (20%) were Black or African American, 20 (2%) were Native Hawaiian or Other Pacific Islander, 825 (70%) were White, and 51 (4%) declined to answer. With regard to ethnicity, 115 respondents (10%) were Hispanic, Latino/Latina, or of Spanish origin, whereas 1017 (86%) were not and 51 (4%) declined to answer. Regarding cancer type and treatment status, 483 respondents (41%) either had or had survived breast cancer and 325 (28%) were being treated for cancer during the survey period. Individuals older than 55 years were more likely to say that they would only participate in trials no farther from their home than their regular care health care practitioner compared with younger respondents (26% vs 16%, respectively; P = .02). Higher-income earners (ie, those in households earning >$125 000/y) were significantly more likely than lower-income earners (ie, those in households earning <$70 000/y) to say they would participate in trials requiring additional effort (62% vs 41%, respectively; P = .03). If given the opportunity to enroll in a cancer clinical trial that required travel farther than their regular care, a majority of respondents (range, 60%-85%) indicated that they would be more likely to participate if the trial used remote technology and other tools to decrease the need for travel to a trial site. Conclusions and Relevance: In this cross-sectional study, the survey findings suggest that cancer clinical trials leveraging remote technology and decentralization tools to reduce patient time and travel burden associated with participation may increase the patient consent rate.

The comprehensive analysis of clinical trials registration for IgA nephropathy therapy on ClinicalTrials.gov.

OBJECTIVES: IgA Nephropathy (IgAN) is common chronic kidney disease with a high incidence. This study aims to analyze comprehensively therapeutic clinical trials for IgAN registered on ClinicalTrials.gov. METHODS: Therapeutic trials for IgAN registered on ClinicalTrials.gov. up to 15 August 2021 were obtained. The general characteristics, features of experimental design, treatment strategies, and some main inclusion criteria and outcome measures were accessed. RESULTS: A total of 104 therapeutic clinical trials for IgAN were extracted on ClinicalTrials.gov up to 15 August 2021. Most of these trials explored the treatment for primary IgAN confirmed by renal biopsy in adults. Only 9% of all selected trials had results. Forty-five percent of trials recruited 50 or fewer participants, and 73% were adults or older adults. 99% of trials were interventional studies, and of all the interventional trials, 70% of trials were randomized, and 68% exercised a parallel assignment of intervention model. Immunosuppression was the most studied for the treatment of IgAN. Moreover, many novel agents had been increasingly studied in recent years. Furthermore, the inclusion criteria and primary outcome measures in these trials were diverse, and the level of proteinuria and change of proteinuria levels were the most used as inclusion criteria and primary outcome, respectively. CONCLUSIONS: The majority of therapeutic trials for IgAN were randomized, none masking and parallel-assignment interventional studies, primarily recruiting adult patients as research subjects. These trials had relatively small sample sizes and short observation. Thus, more large-scale, multicenter, and randomized controlled trials are still needed to improve the management for IgAN.