Dataset Information

Fragility of randomized trials supporting cancer drug approvals stratified by approval pathway and review designations.

ABSTRACT:

Background

It has been suggested that the results from fragile trials are less likely to translate into benefit in routine clinical practice.

Methods

We searched the Food and Drug Administration (FDA) archives to identify drug approvals for solid organ malignancies between 2010 and 2019. We calculated the Fragility Index (FI) supporting each approval, using methods to account for time-to-event. We compared FI and trial and approval characteristics using Mann-Whitney U and Kruskal-Wallis test. Using logistic regression, we examined study characteristics associated with withdrawal of consent or lost to follow-up (WCLFU) exceeding the calculated FI.

Results

The median FI among 125 included studies was 23 (range 1-322). The FI was ≤10 in 35 studies (28%), 11-20 in 21 (17%), and >20 in 69 (55%). The median FI/Nexp was 7.7% (range 0.1-51.7%). The median FI was significantly lower among approvals processed through the accelerated vs regular pathway (5.5 vs 25, p = 0.001), but there was no difference in median FI/Nexp. The WCLFU exceeded FI in 42% of studies. Overall survival endpoints were more likely to have a WCLFU exceeding FI (OR 3.16, p = 0.003). WCLFU exceeding FI was also associated with a lesser magnitude of effect (median HR 0.69 vs 0.55, p < 0.001). In a sensitivity analysis including only studies with 1:1 randomization, 51% of studies had WCLFU >FI.

Conclusion

The median FI among all trials was 23, and WCLFU exceeded FI in 42%. Comparative trials in solid tumors supporting approval through the accelerated pathway are more fragile compared to trials approved through the regular pathway, an observation likely explained by a lower sample size in the experimental arm.

SUBMITTER: Wilson BE

PROVIDER: S-EPMC8366090 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BackgroundCardiovascular disease (CVD) has become an increasingly common limitation to effective anticancer therapy. Yet, whether CVD events were consistently reported in pivotal trials supporting contemporary anticancer drugs is unknown.ObjectivesThe authors sought to evaluate the incidence, consistency, and nature of CVD event reporting in cancer drug trials.MethodsFrom the Drugs@FDA, clinicaltrials.gov, MEDLINE, and publicly available U.S. Food and Drug Administration (FDA) drug reviews, all reported CVD events across latter-phase (II and III) trials supporting FDA approval of anticancer drugs from 1998 to 2018 were evaluated. The primary outcome was the report of major adverse cardiovascular events (MACE), defined as incident myocardial infarction, stroke, heart failure, coronary revascularization, atrial fibrillation, or CVD death, irrespective of treatment arm. The secondary outcome was report of any CVD event. Pooled reported annualized incidence rates of MACE in those without baseline CVD were compared with reported large contemporary population rates using relative risks. Population risk differences for MACE were estimated. Differences in drug efficacy using pooled binary endpoint hazard ratios on the basis of the presence or absence of reported CVD were also assessed.ResultsOverall, there were 189 trials, evaluating 123 drugs, enrolling 97,365 participants (58.5 ± 5 years, 46.0% female, 72.5% on biologic, targeted, or immune-based therapies) with 148,138 person-years of follow-up. Over a median follow-up of 30 months, 1,148 incidents of MACE (375 heart failure, 253 myocardial infarction, 180 strokes, 65 atrial fibrillation, 29 revascularizations, and 246 CVD deaths; 792 in the intervention vs. 356 in the control arm; p < 0.01) were reported from the 62.4% of trials noting any CVD. The overall weighted-average incidence was 542 events per 100,000 person-years (716 per 100,000 in the intervention arm), compared with 1,408 among similar-aged non-cancer trial subjects (relative risk: 0.38; p < 0.01), translating into a risk difference of 866. There was no association between reporting CVD events and drug efficacy (hazard ratio: 0.68 vs. 0.67; p = 0.22).ConclusionsAmong pivotal clinical trials linked to contemporary FDA-approved cancer drugs, reported CVD event rates trail expected population rates.

Project description:ImportanceWhile there have been multiple assessments of clinical trials leading to anticancer drug approvals by the US Food and Drug Administration (FDA), the cumulative percentage of approvals based on trials with a limitation remains uncertain.ObjectiveTo assess the percentage of clinical trials with limitations in 4 domains-lack of randomization, lack of significant overall survival advantage, inappropriate use of crossover, and use of suboptimal control arms-that led to FDA approvals from June 30, 2014, to July 31, 2019.Design, setting, and participantsThis observational analysis included all anticancer drug indications approved by the FDA from June 30, 2014, through July 31, 2019. All indications were investigated, and each clinical trial was evaluated for design, enrollment period, primary end points, and presence of a limitation in the domains of interest. The standard-of-care therapy was determined by evaluating the literature and published guidelines 1 year prior to the start of clinical trial enrollment. Crossover was examined and evaluated for optimal use. The percentage of approvals based on clinical trials with any or all limitations of interest was then calculated.Main outcomes and measuresEstimated percentage of clinical trials with limitations of interest that led to an anticancer drug marketing authorization by the FDA.ResultsA total of 187 trials leading to 176 approvals for 75 distinct novel anticancer drugs by the FDA were evaluated. Sixty-four (34%) were single-arm clinical trials, and 123 (63%) were randomized clinical trials. A total of 125 (67%) had at least 1 limitation in the domains of interest; 60 of the 125 trials (48%) were randomized clinical trials. Of all 123 randomized clinical trials, 37 (30%) lacked overall survival benefit, 31 (25%) had a suboptimal control, and 17 (14%) used crossover inappropriately.Conclusions and relevanceTwo-thirds of cancer drugs are approved based on clinical trials with limitations in at least 1 of 4 essential domains. Efforts to minimize these limitations at the time of clinical trial design are essential to ensure that new anticancer drugs truly improve patient outcomes over current standards.

Project description:ImportanceTo date, an empirical evaluation of the quality of control arms in randomized clinical trials (RCTs) leading to anticancer drug approvals by the US Food and Drug Administration (FDA) has not been undertaken.ObjectiveWe sought to estimate the percentage of RCTs that used a control arm deemed suboptimal and led to FDA approval of anticancer drugs from January 1, 2013, to July 31, 2018.Design, setting, and participantsThis quality improvement study included 143 anticancer drug approvals granted by the FDA from January 1, 2013, to July 31, 2018. All approvals based on single-arm studies (48 approvals) were excluded. Approvals based on RCTs were further investigated and each trial was analyzed for design, time of patient accrual, control arm, and primary end point. Standard-of-care therapy was determined by evaluating the literature and published guidelines 1 year prior to the start of trial enrollment. The percentage of approvals based on RCTs that used suboptimal control arms was then calculated. The quality of the control arm was deemed suboptimal if the choice of control agent was restricted to exclude a recommended agent, the control arm was specified but the recommended agent was unspecified, and if prior RCT data had demonstrated that the control agent was inferior to an available alternative.Main outcomes and measuresEstimated percentage of RCTs that used suboptimal control arms that led to FDA approval of anticancer agents between January 1, 2013, to July 31, 2018.ResultsA total of 145 studies that led to 143 drug approvals between January 1, 2013, and July 31, 2018, were included. Of these studies, 48 single-arm studies were excluded. The remaining 97 studies led to 95 drug approvals. Of these 95 approvals, 16 (17%) were based on RCTs with suboptimal control arms; 15 were international trials, and 1 was conducted in the United States. The type of approval was regular in 15 trials and accelerated in 1 trial. When categorized by the nature of suboptimal control, 4 (25%) trials omitted active treatment in control arm by limiting investigator's choice, 11 (63%) trials omitted active treatment in the control arm by using a control agent known to be inferior to other available agents or not allowing combinations, and 1 (13%) trial used a previously used treatment in the control arm with a known lack of benefit associated with reexposure.Conclusions and relevanceAlthough anticancer drug approvals are increasing, a proportion of these drugs are reaching the market without proven superiority to what is considered the standard of care at the time of patient enrollment in pivotal trials. The choice of control arm should be optimized to ensure that new anticancer agents being marketed are truly superior to what most clinicians would prescribe outside a clinical trial setting.

Project description:Background In 1993, the US Food and Drug Administration established guidelines to increase diversity by sex and race/ethnicity of participants in clinical trials supporting novel drug approvals. In this study we investigated the 10-year trends of participation of women and minorities in pivotal trials supporting approval of new molecular entities in cardiometabolic drugs from January 2008 to December 2017. Methods and Results A list of new molecular entities was abstracted from publicly available data at Drugs@Fda. Sex and race/ethnicity data were collected from trial publications. Linear regression analysis was performed to assess the relation between drug approval year and proportion of women and minorities enrolled. Thirty-five novel cardiovascular (n=24) and diabetes mellitus (n=11) drugs were approved by the US Food and Drug Administration during the study period. The median number of participants supporting each drug was 5930 (interquartile range, 3175-10 942). Women represented 36% (n=108 052) of trial participants (n=296 163). Women were underrepresented compared with their proportion of the disease population in trials of coronary heart disease (participation-to-prevalence ratio, 0.52), heart failure (participation-to-prevalence ratio, 0.58), and acute coronary syndrome (participation-to-prevalence ratio, 0.68). Among trial participants, 81% were white, 4% black, 12% Asian, and 11% Hispanic/Latino. There was no significant association between enrollment of women (P=0.29) or underrepresented minorities (P=0.45) with the drug approval year. Conclusions Over the past decade (2008-2017), women and minorities, particularly blacks, have continued to be inadequately represented in pivotal cardiometabolic clinical trials that support US Food and Drug Administration approval of new molecular entities. This may have major implications in determining efficacy of such therapies in these groups, and may impair generalizability of trial results to routine clinical practice.