Characteristics and Research Waste Among Randomized Clinical Trials in Gastric Cancer

IMPORTANCE

The results of numerous large randomized clinical trials (RCTs) have changed clinical practice in gastric cancer (GC). However, research waste (ie, unpublished data, inadequate reporting, or avoidable design limitations) is still a major challenge for evidence-based medicine.

OBJECTIVES

To determine the characteristics of GC RCTs in the past 20 years and the presence of research waste and to explore potential targets for improvement.

DESIGN, SETTING, AND PARTICIPANTS

In this cross-sectional study of GC RCTs, ClinicalTrials.gov was searched for phase 3 or 4 RCTs registered from January 2000 to December 2019 using the keyword gastric cancer. Independent investigators undertook assessments and resolved discrepancies via consensus. Data were analyzed from August through December 2020.

MAIN OUTCOMES AND MEASURES

The primary outcomes were descriptions of the characteristics of GC RCTs and the proportion of studies with signs of research waste. Research waste was defined as unpublished data, inadequate reporting, or avoidable design limitations. Publication status was determined by searching PubMed and Scopus databases. The adequacy of reporting was evaluated using the Consolidated Standards of Reporting Trials (CONSORT) reporting guideline checklist. Avoidable design limitations were determined based on existing bias or lack of cited systematic literature reviews. In the analyses of research waste, 125 RCTs that ended after June 2016 without publication were excluded.

RESULTS

A total of 262 GC RCTs were included. The number of RCTs increased from 25 trials in 2000 to 2004 to 97 trials in 2015 to 2019, with a greater increase among RCTs of targeted therapy or immunotherapy, which increased from 0 trials in 2000 to 2004 to 36 trials in 2015 to 2019. The proportion of RCTs that were multicenter was higher in non-Asian regions than in Asian regions (50 of 71 RCTs [70.4%] vs 96 of 191 RCTs [50.3%]; P = .004). The analysis of research waste included 137 RCTs, of which 81 (59.1%) were published. Among published RCTs, 65 (80.2%) were judged to be adequately reported and 63 (77.8%) had avoidable design defects. Additionally, 119 RCTs (86.9%) had 1 or more features of research waste. Study settings that included blinding (odds ratio [OR], 0.56; 95% CI, 0.33-0.93; P = .03), a greater number of participants (ie, ≥200 participants; OR, 0.07; 95% CI, 0.01-0.51; P = .01), and external funding support (OR, 0.22; 95% CI, 0.08-0.60; P = .004) were associated with lower odds of research waste. Additionally, 35 RCTs (49.3%) were referenced in guidelines, and 18 RCTs (22.2%) had their prospective data reused.

CONCLUSIONS AND RELEVANCE

To our knowledge, this study is the first to describe the characteristics of GC RCTs in the past 20 years, and it found a research waste burden, which may provide evidence for the development of rational RCTs and reduction of waste in the future.

Use of Both Qualitative and Quantitative Methods to Estimate Meaningful Change Thresholds for Key Endpoints in Pediatric Asthma Trials

INTRODUCTION

Diary-derived symptom score and rescue medication use endpoints, such as symptom-free days (SFDs) and rescue medication-free days (RFD), are frequently used as clinical trial endpoints. Estimates of meaningful change for SFDs and RFDs have not been generated in pediatric populations. This research aimed to generate evidence supporting estimates of the individual within-patient changes that constitute an important or meaningful change in SFDs, RFDs, and updated estimates on the Childhood Asthma Control Test (C-ACT) in pediatric asthma populations aged 5-11 years.

METHODS

Semistructured, qualitative interviews were conducted with children (ages 8-11 years) who had asthma and parents/caregivers of children (4-11 years) with asthma. Before the interview (4-9 days) participants were asked to complete a morning and evening diary.

RESULTS

On average, parent/caregiver estimates of the difference in SFDs between a "very bad" and a "little bad" week for their children's asthma were largely concordant with the values reported by their children (differences of 1.8 and 1.4 SFDs, respectively). Both parents/caregivers and children were able to articulate what a meaningful level of change would be on the C-ACT at the item level. This qualitative study generated C-ACT item-level meaningful change estimates in the region of 1-3 category change, which potentially suggests that, if scaled up to represent C-ACT total score, this would lead to change estimates of 7-15 points.

CONCLUSIONS

Our findings suggest that both children with asthma and parents/caregivers can quantitatively estimate and to some extent qualitatively articulate meaningful change in SFDs and RFDs.

Phase IV non-inferiority trials and additional claims of benefit

BACKGROUND

Non-inferiority (NI) trials in drug research are used to demonstrate that a new treatment is not less effective than an active comparator. Since phase IV trials typically aim at informing a clinical decision, the value of a phase IV non-inferiority trial hinges also on its clinical relevance. In such trials, clinical relevance would refer to the added benefit claims of a specific drug, apart from efficacy, relative to its comparator drug in the trial.

METHODS

In this study, we reviewed 41 phase IV trials and extracted information on whether the authors mentioned any additional benefit beyond the NI (efficacy) claim of the drug and whether the additional benefit was proven in the trial. We checked whether the additional claim was based on descriptions only or on formal statistical analyses.

RESULTS

Our results showed that 22 out of the 41 NI trials mentioned additional benefit of the test drug and most of these claims were related to the safety profile. Of all the post-authorization NI trials that claimed additional benefit, 10 out of 22 NI trials used formal statistical analyses to show additional benefit, and only one included a sample size calculation for the additional benefit prior to the trial.

CONCLUSION

We conclude that there is room for improvement in terms of designing phase IV NI trials with added benefit claims and in proving these additional claims.

Phase 4 research: what happens when the rubber meets the road?

Approval of a novel drug is oftentimes seen as the end of the development pathway. However, the appearance of rare but serious side effects in patients taking approved drugs has led to increased attention to phase 4, or postmarketing, research. Traditionally, postmarketing research relied on reports from clinicians to monitor for unexpected toxicity. However, such reporting will produce a biased assessment of risk due to underreporting of toxic effects in older medications. The availability of large, representative databases and more flexible analysis tools has led to comprehensive and near "real-time" surveillance programs. These programs have been used by the US Food and Drug Administration to explore toxicities of approved medications. The need for effective tools with which to monitor clinically relevant outcome events has been further increased by the development of accelerated pathways to drug approval. In areas without effective treatments, such pathways lead to licensure without rigorous clinical efficacy data. Continued approval is frequently made contingent on the availability of postmarketing surveillance data demonstrating improvements in clinical end points and these data can also be used to monitor for unexpected toxicity.

[The GCP directive--consequences for clinical drug research]

The contents and implications of the EU Directive on good clinical (research) practice (GCP) regarding drug trials are described. As of May 2003, clinical researchers in Denmark must have standard operation procedures, conduct monitoring, consider quality assurance, and expect inspections. The industry may be better prepared, but the Directive makes GCP part of the law and phase IV studies become subject to GCP. Patients will be assured the same quality in trials irrespective of the industry or investigator being the sponsor and may look forward to quality improvement of drug trials.

Problems with publishing results of interim analyses of randomized clinical trials

PURPOSE

This purpose of this study was to illustrate how publication of interim analyses of randomized clinical trials (RCTs) can cause problems in the interpretation of final results.

METHOD

The effect of publishing interim analyses on the results of a typical HIV RCT comparing regimens of registered antiretroviral drugs was illustrated using a simulation study. Simulations modeled an RCT comparing the effect of two treatment combinations on changes in log HIV viral load from baseline. Publication of interim results at 6 months was assumed to lead to 50% of patients switching from the poorer treatment if interim results were statistically significant (p <.05), 20% of patients switching from the poorer treatment if interim results were marginally significant (.05 < p <.20), and 10% of all patients switching treatment if interim results were not statistically significant. Three scenarios were simulated: a large treatment difference (0.4 log HIV viral load), a moderate difference (0.2 log), and no treatment difference (0.0 log).

RESULTS

The simulation study showed that if the true treatment difference was large (0.4 log) the power of the trial was reduced from over 80% at 6 months to under 37% at 12 months. Furthermore, given the statistical significance of the interim analysis results at 6 months, the simulations illustrated that the trial results would appear similar at 12 months, regardless of the true underlying treatment difference.

CONCLUSION

The simulations reinforce the fact that publication of interim analyses of RCTs can affect the future conduct of a trial and make interpretation of final results difficult.

"How much do you get paid if I volunteer?" Suggested institutional policy on reward, consent, and research

Pharmaceutical companies often ask practicing physicians to conduct phase IV or postmarketing research on new drugs. Companies pay physicians to enroll their patients and report dosage and side-effect information. Postmarketing research embraces a multibillion dollar effort at promotion and familiarization, but subjects' informed consent to it normally does not include physician reward. Improving investigators' financial status while increasing medical risks to phase IV subjects is ethically unsound, especially if subjects are unaware of investigators' rewards. We suggest a model policy and guidelines that affirm subjects' need for informed consent, investigators' need for recognition and support, and institutions' need to protect patients from undisclosed risk and relations.

[Ethics problems in phase IV of drug studies]

Phase IV clinical studies include all investigations carried out after the approval of drugs. The objective of these studies is well defined: to gain additional knowledge on efficacy and safety of drugs. There are uncertainties however with regard to which kind of study design is appropriate to provide scientifically valid contributions. In the present article we will clarify why an experimental design (e.g. randomized clinical trial) is ordinarily required, on the basis of scientific and ethical concerns, to answer questions concerning efficacy even after drug commercialization. Viceversa, non experimental designs (from case series analysis to cohort and case control studies) are indicated to investigate drug effects in current practice if the objective is to evaluate safety.

FDA perspective on specifications for biotechnology products--from IND to PLA

Quality standards are obligatory throughout development, approval and post-marketing phases of biotechnology-derived products, thus assuring product identity, purity, and potency/strength. The process of developing and setting specifications should be based on sound science and should represent a logical progression of actions based on the use of experiential data spanning manufacturing process validation, consistency in production, and characterization of relevant product properties/attributes, by multiple analytical means. This interactive process occurs in phases, varying in rigour. It is best described as encompassing a framework which starts with the implementation of realistic/practical operational quality limits, progressing to the establishment/adoption of more stringent specifications. The historical database is generated from preclinical, toxicology and early clinical lots. This supports the clinical development programme which, as it progresses, allows for further assay method validation/refinement, adoption/addition due to relevant or newly recognized product attributes or rejection due to irrelevance. In the next phase, (licensing/approval) specifications are set through extended experience and validation of both the preparative and analytical processes, to include availability of suitable reference standards and extensive product characterization throughout its proposed dating period. Subsequent to product approval, the incremental database of test results serves as a natural continuum for further evolving/refining specifications. While there is considerable latitude in the kinds of testing modalities finally adopted to establish product quality on a routine basis, for both drugs and drug products, it is important that the selection takes into consideration relevant (significant) product characteristics that appropriately reflect on identity, purity and potency.

Guidelines for the implementation of drug utilization observation (DUO) studies in psychopharmacological therapy. The "Phase IV Research" Task-Force of the Association for Neuropsychopharmacology and Pharmacopsychiatry (AGNP)

The task-force on Phase-IV-Research of the Association for Neuropharmacology and Pharmacopsychiatry (AGNP) has developed guidelines for the implementation of scientifically sound drug utilisation observation studies (DUO studies). These guidelines have been adopted by the executive committee as the position of the association. DUO studies are prospective pharmacoepidemiological studies, by which prescription, illness, and patient data of individual patients are collected without interference with the routine course of treatment. They can answer questions on the interaction of treatment modalities with positive and negative treatment outcome. Scientific standards require that there is a study protocol which describes the epidemiological, statistical, procedural, and quality assurance methodology and states who is responsible for what. As such studies can violate data protection regulations or can be used for sales instead of scientific purposes, consultation of an ethics committee is recommended.