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Analysis of terminated pulmonary hypertension clinical trials. What are we doing wrong?
Mohammad Abdulelah1, Zaid A Abdulelah2, Muayad Azzam3
1Department of Internal Medicine, University of Massachusetts Chan Medical School - Baystate, Springfield, MA 01199, USA.
Abstract:
Despite significant interest in the diagnosis and treatment of pulmonary hypertension (PH) over the past two decades, there have been no notable advancements in reducing mortality. One contributing factor to this lack of progress is the insufficient number of well-designed and conducted trials. We aimed to evaluate factors associated with termination of PH clinical trials, to serve as a reference when designing future trials. We searched the ClinicalTrials.gov database for PH clinical trials conducted between January 1st 2000 to December 31st 2020. Information collected and analyzed included trial design, status, and publication status. Of the 240 analyzed clinical trials, 81% evaluated therapeutic interventions. Around 30.4% of the trials were terminated, most commonly due to recruitment issues. Terminated trials had a significantly lower number of enrolled patients when compared to trials that were completed (p= .017). Furthermore, there was an overall negative correlation between the year of trial initiation and the total number of enrolled patients (r= -0.18; p= .013). The likelihood of termination decreased by 1.9% for every additional enrolled patient. Ultimately, only 37.5% of the trials have been published. There was a significant positive correlation between number of patients enrolled and the journal's impact factor (r = 0.4, p < 0.05). Pharmaceutical companies sponsored the majority of the trials. The termination rate of PH trials is higher than other conditions. Factors such as recruitment contribute significantly to termination. Further studies are required to evaluate the challenges associated with recruiting this patient population.
Insights
Pulmonary hypertension (PH) clinical trials face high termination rates, often due to recruitment challenges. Increasing patient enrollment can decrease trial termination likelihood, improving research outcomes for PH treatments.
Area of Science:
- Cardiology
- Clinical Trials
- Pulmonary Medicine
Background:
- Pulmonary hypertension (PH) diagnosis and treatment have seen limited mortality reduction over 20 years.
- Insufficiently designed and conducted clinical trials contribute to the lack of progress in PH.
- Understanding factors leading to PH trial termination is crucial for future study design.
Purpose of the Study:
- To evaluate factors associated with the termination of pulmonary hypertension clinical trials.
- To provide insights for designing more successful future PH clinical trials.
Main Methods:
- A systematic search of the ClinicalTrials.gov database for PH trials (2000-2020).
- Analysis of trial design, status, and publication data for 240 trials.
- Statistical evaluation of factors influencing trial termination, including patient enrollment numbers.
Main Results:
- 30.4% of analyzed PH trials were terminated, primarily due to recruitment issues.
- Terminated trials enrolled significantly fewer patients than completed trials (p=0.017).
- Only 37.5% of trials were published, with enrollment correlating positively with journal impact factor.
Conclusions:
- Recruitment challenges significantly contribute to the high termination rate of PH clinical trials.
- Increasing patient enrollment is associated with a decreased likelihood of trial termination.
- Further research is needed to address recruitment difficulties in the PH patient population.
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