Reasons for Premature Conclusion of Late Phase Clinical Trials: An Analysis of ClinicalTrials.gov Registered Phase III Trials

Premature termination of clinical trials in Spain: reasons, characteristics, and opportunities to improve

PURPOSE

The aim of this study is to determine the rate of prematurely terminated clinical trials (CTs) and describe primary reasons and characteristics, and suggest strategies to improve.

METHODS

We performed a retrospective, observational, cross-sectional study including all CTs registered in the Spanish Registry of Clinical Studies (REec) from January 1, 2013 to November 31, 2021. A descriptive analysis of reasons for premature termination was made. To assess characteristics associated with a premature termination, the relative risks (RR) with a 95% confidence interval were calculated.

RESULTS

In total, 21% (718) of CT were prematurely terminated. Reasons for premature termination included patient recruitment issues in 25% (179) of cases, efficacy or futility problems in 18% (132), and commercial or strategic decisions from the sponsor in 12% (87). Characteristics significantly associated with an increased risk of premature termination included the following: presence of placebo (RR 2.08); multiple study sites (RR 1.32); pediatric and geriatric populations (RR 1.29 children; RR 1.47 preschoolers; RR 1.92 newborns; RR 1.27 > 64 years of age). In addition, circumstances such as investigations in phase II (RR 1.21), of cancer (RR 1.37), and of digestive pathology (RR 1.65) were also associated with increased risk of premature termination.

CONCLUSION

Recruitment of the study subjects in a CT must be meticulous and account for age of participants. In addition, CT study sites should be evaluated to ensure they have appropriate resources and the desired patient population. Based on intermediate analyses, CT protocols should describe the criteria to terminate a study due to futility. These approaches are essential to avoid harm to participants, ensure internal validity of studies, and improve the use of resources in CT development.

Evolving a national clinical trials learning health system

Clinical trials generate key evidence to inform decision making, and also benefit participants directly. However, clinical trials frequently fail, often struggle to enroll participants, and are expensive. Part of the problem with trial conduct may be the disconnected nature of clinical trials, preventing rapid data sharing, generation of insights and targeted improvement interventions, and identification of knowledge gaps. In other areas of healthcare, a learning health system (LHS) has been proposed as a model to facilitate continuous learning and improvement. We propose that an LHS approach could greatly benefit clinical trials, allowing for continuous improvements to trial conduct and efficiency. A robust trial data sharing system, continuous analysis of trial enrollment and other success metrics, and development of targeted trial improvement interventions are potentially key components of a Trials LHS reflecting the learning cycle and allowing for continuous trial improvement. Through the development and use of a Trials LHS, clinical trials could be treated as a system, producing benefits to patients, advancing care, and decreasing costs for stakeholders.

Room4Birth - The effect of giving birth in a hospital birthing room designed with person-centred considerations: A Swedish randomised controlled trial

OBJECTIVE

To evaluate if a birthing room designed with person-centred considerations improves labour and birth outcomes for nulliparous women when compared to regular birthing rooms.

METHODS

A randomised controlled trial was conducted at a Swedish labour ward between January 2019 and October 2020. Nulliparous women in spontaneous labour were randomised either to a birthing room designed with person-centred considerations (New room) or a Regular room. The primary outcome was a composite of four variables: vaginal non-instrumental birth; no oxytocin augmentation; postpartum blood loss < 1000 ml; and a positive childbirth experience. To detect a difference of 8% between the groups, 1274 study participants were needed, but the trial was terminated early due to consequences of the Covid-19 pandemic.

RESULTS

A total of 406 women were randomised; 204 to the New room and 202 to the Regular room. There was no significant difference in the primary outcome between the groups (42.2% versus 35.1%; odds ratio: 1.35, 95% Confidence Interval 0.90-2.01; p = 0.18). Participants in the New room used epidural analgesia to a lower extent (54.4% versus 65.3%, relative risk: 0.83, 95% Confidence Interval 0.71-0.98; p = 0.03) and reported to a higher degree that the room contributed to a sense of safety, control, and integrity (p=<0.001).

CONCLUSIONS

The hypothesis that the New room would improve the primary outcome could not be verified. Considering the early discontinuation of the study, results should be interpreted with caution. Nevertheless, analyses of our secondary outcomes emphasise the experiential value of the built birth environment in improving care for labouring women.

Obstacles to the reuse of study metadata in ClinicalTrials.gov

Metadata that are structured using principled schemas and that use terms from ontologies are essential to making biomedical data findable and reusable for downstream analyses. The largest source of metadata that describes the experimental protocol, funding, and scientific leadership of clinical studies is ClinicalTrials.gov. We evaluated whether values in 302,091 trial records adhere to expected data types and use terms from biomedical ontologies, whether records contain fields required by government regulations, and whether structured elements could replace free-text elements. Contact information, outcome measures, and study design are frequently missing or underspecified. Important fields for search, such as condition and intervention, are not restricted to ontologies, and almost half of the conditions are not denoted by MeSH terms, as recommended. Eligibility criteria are stored as semi-structured free text. Enforcing the presence of all required elements, requiring values for certain fields to be drawn from ontologies, and creating a structured eligibility criteria element would improve the reusability of data from ClinicalTrials.gov in systematic reviews, metanalyses, and matching of eligible patients to trials.

Optimizing clinical trial design using prospective cohort study data: a case study in neuro-urology

Study Design

Simulations using data from a prospective cohort study.

Objectives

To illustrate how prospective cohort data can be employed in randomized controlled trial (RCT) planning to assess feasibility and operational challenges, using TASCI (Transcutaneous tibial nerve stimulation in patients with Acute Spinal Cord Injury to prevent neurogenic detrusor overactivity: a nationwide randomized, sham-controlled, double-blind clinical trial) as a case study.

Setting

Spinal cord injury rehabilitation centers in Switzerland.

Methods

TASCI is nested in the multicenter Swiss Spinal Cord Injury Cohort Study (SwiSCI), which prospectively includes patients with acute spinal cord injury. In simulations, data from 640 patients, collected by SwiSCI, were used to investigate different scenarios of patient eligibility and study consent, as well as the performance of the randomization list. Descriptive analysis was used to describe the population of interest and the simulation results; multivariable logistic regression analysis was performed to identify predictors of discharge within the TASCI intervention time period.

Results

The recruitment target of 114 patients is obtainable within the originally envisioned three-year time period under the most favorable recruitment scenario examined. The distribution of the primary prognostic factor produced imbalance in the randomization lists and informed further discussion of the cut-off values used in stratification. Influxes of patients resulted in overlapping intervention periods for multiple participants, which guided resource allocation. Early discharge was related to the primary prognostic factor and study center, but is only anticipated in about 8% of participants.

Conclusions

Prospective cohort data are a very valuable resource for planning RCTs.

How to deal with a temporary suspension and restarting your trial: our experiences and lessons learnt

Whilst the issues around early termination of randomised controlled trials (RCTs) are well documented in the literature, trials can also be temporarily suspended with the real prospect that they may subsequently restart. There is little guidance in the literature as to how to manage such a temporary suspension. In this paper, we describe the temporary suspension of a trial within our clinical trials unit because of concerns over the safety of transvaginal synthetic mesh implants. We also describe the challenges, considerations, and lessons learnt during the suspension that we are now applying in the current COVID-19 pandemic which has led to activities in many RCTs across the world undergoing a temporary suspension.

There were three key phases within the temporary suspension: the decision to suspend, implementation of the suspension, and restarting. Each of these phases presented individual challenges which are discussed within this paper, along with the lessons learnt. There were obvious challenges around recruitment, delivery of the intervention, and follow-up. Additional challenges included communication between stakeholders, evolving risk assessment, updates to trial protocol and associated paperwork, maintaining site engagement, data-analysis, and workload within the trial team and Sponsor organisation.

Based on our experience of managing a temporary suspension, we developed an action plan and guidance (see Additional File 1) for managing a significant trial event, such as a temporary suspension. We have used this document to help us manage the suspension of activities within our portfolio of trials during the current COVID-19 pandemic.