Changes in Key Recruitment Performance Metrics from 2008-2019 in
Industry-sponsored Phase III Clinical Trials Registered at
ClinicalTrials.gov
Abstract
Background: Increasing costs and complexity in clinical trials requires
recruitment of more narrowly defined patient populations. However,
recruitment for clinical trials remains a considerable challenge. Aim:
Our overall aim was to quantify recruitment performance in
industry-sponsored phase III clinical trials conducted globally during
2008-2019 with primary aim to examine development of overall clinical
trial measures (number of trials completed, number of participants
enrolled, trial duration in months) and key recruitment metrics
(recruitment rate, number of sites, number of patients enrolled per
site). Methods: The publicly available AACT database containing data on
all trials registered at ClinicalTrials.gov since 2008 was used. The
analysis was completed during three time periods from 2008-2019 of 4
years each. Results and conclusion: Recruitment duration for
industry-sponsored phase III clinical trials have increased
significantly during the last 12 years from an average recruitment
period of 13 months (IQR 7-23) in 2008-2011 to 18 months (IQR 11-28) in
2016-2019 (p = 0.0068). Further, phase III clinical trials have
increased the number of registered sites per clinical trial by more than
30% during the last 12 years from a median number 43 sites (IQR 17-84)
in 2012-2015 to 64 sites (IQR 30-118) in 2016-2019 (p = 0.025), and
concurrently, the number of participants enrolled in clinical research
has decreased significantly from 2012-2015 and 2016-2019 (p = 0.046). We
believe that these findings indicate that recruitment for phase III
clinical trials is less effective today compared to 12 years ago.