Analysis of the Frequency, Characteristics, and Reasons for Termination of Spine-related Clinical Trials

Why are clinical trials of deep brain stimulation terminated? An analysis of clinicaltrials.gov

Background

Although deep brain stimulation (DBS) has established uses for patients with movement disorders and epilepsy, it is under consideration for a wide range of neurologic and neuropsychiatric conditions.

Objective

To review successful and unsuccessful DBS clinical trials and identify factors associated with early trial termination.

Methods

The ClinicalTrials.gov database was screened for all studies related to DBS. Information regarding condition of interest, study aim, trial design, trial success, and, if applicable, reason for failure was collected. Trials were compared and logistic regression was utilized to identify independent factors associated with trial termination.

Results

Of 325 identified trials, 79.7% were successful and 20.3% unsuccessful. Patient recruitment, sponsor decision, and device issues were the most cited reasons for termination. 242 trials (74.5%) were interventional with 78.1% successful. There was a statistically significant difference between successful and unsuccessful trials in number of funding sources (p = 0.0375). NIH funding was associated with successful trials while utilization of other funding sources (academic institutions and community organizations) was associated with unsuccessful trials. 83 trials (25.5%) were observational with 84.0% successful; there were no statistically significant differences between successful and unsuccessful observational trials.

Conclusion

One in five clinical trials for DBS were found to be unsuccessful, most commonly due to patient recruitment difficulties. The source of funding was the only factor associated with trial success. As DBS research continues to grow, understanding the current state of clinical trials will help design successful future studies, thereby minimizing futile expenditures of time, cost, and patient engagement.

Sponsorship of clinical trials related to the spine: Trends over time and comparative analysis of trial characteristics by sponsorship type

Background

Clinical trials are crucial to advance products and procedures related to the spine. ClinicalTrials.gov is an internet-based registry and results database that catalogs trial characteristics, such as intervention types, phase, randomization, and blinding. Sponsorship trends have not been specifically evaluated for spine-related clinical trials, nor have trial characteristics been compared among spine-related trials sponsored by institutions, industries, and federal agencies. The purpose of this cross-sectional analysis of spine-related clinical trials was to characterize the types and trends of sponsorship for spine-related clinical trials, and compare trial characteristics among trials sponsored by institutions, industries, and federal agencies.

Methods

ClinicalTrials.gov was queried for clinical trials started from the launch of ClinicalTrials.gov (February 29, 2000) through December 31, 2022, using the term "spine." Trial characteristics were abstracted, including start year, intervention type, phase, randomization, and blinding. Univariate and multivariate analyses were performed to determine associations between sponsorship type and other trial characteristics.

Results

A total of 4,484 clinical trials were identified, of which 78 trials were excluded due to incomplete reporting of trial registration data. From 2000 through 2022, the number of spine-related trials initiated annually markedly increased (from 21 to 453, representing an increase of 2,057%). This was predominantly driven by an increase in the number of institutionally sponsored trials. Relative to trials with institutional sponsorship, industry sponsorship was independently associated with different intervention types, phases of study, lack of randomization, and lack of blinding. Relative to trials with institutional sponsorship, federal sponsorship was independently associated with intervention type, and phase of study.

Conclusions

From 2000 through 2022, the number of spine-related clinical trials initiated annually markedly increased, driven by an increase in institutionally sponsored trials. Specific trial characteristics were more or less likely for industrially or federally sponsored trials relative to institutionally sponsored trials suggesting the types of clinical trials are shifting over time.

Sponsorship of Clinical Trials Related to the Shoulder and Elbow: Trends Over Time and Comparative Analysis of Trial Characteristics by Sponsorship Type

INTRODUCTION

Sponsorship trends have not been specifically evaluated for shoulder and elbow clinical trials, nor have trial characteristics been compared among shoulder and elbow trials sponsored by institutions, industries, and federal agencies.

METHODS

ClinicalTrials.gov was queried for clinical trials using the terms 'shoulder' and 'elbow.' Trial characteristics were abstracted, including start year, intervention type, phase, randomization, and blinding. Univariate and multivariate analyses were performed to determine associations between sponsorship type and other trial characteristics.

RESULTS

In total, 4,945 shoulder clinical trials and 1,517 elbow clinical trials were identified, of which 26 shoulder clinical trials and seven elbow clinical trials were excluded due to incomplete data. From 2000 to 2022, the number of shoulder and elbow trials initiated annually markedly increased driven by an increase in the number of institutional trials. Relative to trials with institutional sponsorship, industry sponsorship was independently associated with different intervention types, phase of study, lack of randomization, and blinding.

DISCUSSION

From 2000 to 2022, the number of shoulder and elbow clinical trials initiated annually markedly increased, driven by an increase in institutionally sponsored trials. For clinical trials related to the shoulder, design characteristics were found to differ based on study sponsorship type. This suggests that the design characteristics of shoulder-related clinical trials are shifting over time.

Analysis of Terminated Hand and Wrist-Related Clinical Trials

Purpose

While clinical trials provide high-quality evidence guiding medical decision-making, early trial termination can result in both lost time and resources. Our purpose was to investigate the rate of and reasons for clinical trial termination for hand and wrist-related conditions and identify study characteristics associated with early trial termination.

Methods

The ClinicalTrials.gov database was queried for all hand and wrist-related clinical trials. All terminated and completed trials were reviewed, with characteristics and reasons for termination recorded. Study characteristics included type, purpose, intervention assessed, enrollment, group allocation, blinding, trial phase, sponsor type, and geographic region. Chi-square test was used to identify associations between trial characteristics and terminated versus completed status.

Results

A total of 793 hand and wrist-related clinical trials were identified, with 77 trials (10%) terminated prior to completion. The most common reason for termination was "recruitment/retention difficulty," reported in 37 (48%) terminated trials. In comparing competed versus terminated trials, primary purpose (nonobservational studies), enrollment (<50 patients), and geographic region (North America) were all significantly more likely to be terminated. Terminated trials were more likely to have an intervention type investigating a specific device or drug.

Conclusions

Early trial termination for hand and wrist-related conditions is common (10%), with patient recruitment and retention identified as the leading cause of termination. Trials involving potential commercial incentives (those investigating a device or drug) were associated with an increased rate of trial termination.

Clinical relevance

An emphasis on patient enrollment during study design may aid in mitigating the most common cause of early clinical trial termination.

Early Termination of Oncology Clinical Trials in the United States

PURPOSE

The aim of this study was to evaluate the rate of early trial discontinuation of oncology trials and reasons for early termination, to assess potential trends in rates of oncology trial termination, and to perform a comprehensive analysis of predictors of early termination. This study intends to inform efforts in improving efficiency of the oncology clinical trial enterprise.

METHODS

We conducted a cross-sectional study of interventional cancer clinical trials registered in ClinicalTrials.gov database from September 27, 2007 to June 30, 2015, with at least one site listed in the United States. We evaluated predictors of early trial termination using Fisher exact or χ² tests and logistic regression.

RESULTS

Of 8687 trials, 22.74% (n = 1975) were terminated trials. Rates of early trial termination appeared stable over the study. Statistically significant univariate predictors of early termination for any reason include cancer category, phase, funding source, location, and age. In multivariable analysis, trials spanning multiple cancer categories and international trials were less likely to terminate early whereas phase 2 trials and trials funded by academia/foundation were more likely to terminate early. The most common reason for early termination was "Other, Multiple Reasons, or Unknown" (36.9%), followed by accrual issues (34.5%). In multivariate analysis among all terminated trials, supportive care trials, phase 2 trials, and non-industry funded trials had significantly higher odds of trial discontinuation specifically due to poor accrual.

CONCLUSION

In this national sample of cancer clinical trials, early trial discontinuation was common. Many factors influenced early trial termination with poor accrual being a common reason. Specific trial features are associated with differential likelihood of early trial termination for any reason and for early trial termination due to poor accrual.