About 20% of Cancer Clinical Trials Fail Due to Low Patient Recruitment 
​[Posted on: Thursday, 14 January, 2016] 

Patient recruitment challenges plague all clinical trials. Sponsors of clinical trials need to plan robust recruitment campaigns and involve creative solutions to find patients willing to participate in their trials. However, little systematic analysis has been conducted so far to evaluate the impact of poor recruitment on trial failure. That is till now. In a report published in the Journal of the National Cancer Institute, researchers at the University of Washington and the Fred Hutchinson Cancer Research Center reported a mathematical tool to predict how difficult it might be to attract trial participants depending on a range of trial-specific factors. The authors used their tool to evaluate 787 Phase II and III clinical trials sponsored by the National Cancer Institute over a 10 year period (between 2000 and 2011). Low accrual is defined as trials that closed with or were accruing at less than 50% of target. Overall, 18% of cancer clinical trials had very low accrual or were stopped due to low recruitment. The failure rate was almost 25% for randomized trials, and was lowest (11%) for a new investigational agent verses new formulations or new uses of older products. The study presented several interesting reasons for trials failing due to poor recruitment which could help sponsors predict potential challenges to patient recruitment. Open-label trials, where all patients were promised a treatment had lower failure rate compared to randomized trials where the patient may get an approved treatment option or placebo instead of the investigational drug. Trials that required tissue biopsies failed to recruit patient at a higher rate. Other factors include distance from the clinic, patient’s financial situation, and health insurance constraints.  There are some key take home points from this study. First, similar challenges are predicted for other clinical trials, as the reasons for low recruitment were not necessarily linked to the disease being investigated in the clinical trials but practical aspects. Second, this study did not evaluate the impact of recruitment campaign, whether trials with better educational resources and advertisement fared better. It is well-known that recruitment campaigns, advertisement and use of social media leads to higher enrolment. Third, the study pointed out that only about 3-5% of cancer patients participate in clinical trials indicating additional factors such as patient education and awareness of trial availability. Overall the study raises interesting questions but offers few solutions.