U.S. trials sponsored by industry have a higher completion rate, but remain a smaller part of the trial landscape overall and are also completing trials faster with larger enrollments, says a new analysis.

The data show that the composition and design of trials changed between 2000 and 2019 and differed substantially by sponsor type. The number of industry-sponsored trial starts increased almost four-fold in the past 20 years while completion rates fell by more than 50 percent.

The analysis conducted by researchers from Cedars-Sinai Medical Center and Johns Hopkins University looked at 245,999 interventional studies started between 2000 and 2019, analyzing the approximately 55 percent of those that were completed. The research was based on trials listed on ClinicalTrials.gov (CT.gov), with only 47.7 percent of NIH and government-funded trials, 37.8 percent of industry and 16 percent of other sources posting data.

Industry-sponsored trials in 2000 to 2004 numbered 6,772 with a 90.5 percent completion rate. By the period 2015-2019, the number of starts soared to 22,821 but completion dropped to 42 percent. Meanwhile, trial size decreased to a median size of 53 participants from 140 in the period from 2000 to 2004. The median length of industry trials dropped to 1.2 years in 2019 from 3.2 years in 2000.

Even though industry sponsors are outperforming other sponsor types, the assessment of nearly two decades of CT.gov data indicates that trials have diminished in both size and time to completion across the board, leading the study’s authors to conclude that today’s trials may not have the depth of data needed to produce valid results.

The overall median sample size across sponsor types was 60 participants, and patient population sizes decreased over time while studies took less time to finish. Reasons for that trend could include “changes in the types of outcomes being used (e.g., surrogate outcomes and biomarkers as well as patient-reported outcomes), increasing trial-associated costs and greater budget constraints,” the researchers wrote in the study published in the Journal of the American Medical Association.

“With an overall median sample size of 60 persons per trial, the ability to generate meaningful, reproducible differences with such a sample size remains questionable,” wrote Gillian Gresham, Arthur G. Gresham, Jill L. Meinert and Curtis L. Meinert. All four authors work at the Center for Clinical Trials and Evidence Synthesis at Johns Hopkins University in Baltimore and Gillian Gresham works in the department of medicine at Cedars-Sinai Medical Center in Los Angeles.

The study’s authors concluded that “increased funding toward larger randomized clinical trials may be warranted to inform clinical decision-making and guide future research.”

However, the study’s findings contrast with figures from a recent report from the Tufts Center for the Study of Drug Development (CSDD) that found the average length of industry-sponsored trials has increased by almost five months in the past decade (CenterWatch Weekly, July 20).

“Based on an analysis of all drug approvals (2008-2018),” said CSDD director Ken Getz, “the clinical phase is getting longer and the average number of participants per clinical trial is rising, with the exception of Phase 4.”

Industry was the lead sponsor for more phase 3 to 4 trials completed over time, the CT.gov study found, with the NIH and government agencies taking the lead on completed phase 1 to 2 trials.

The researchers noted that industry completed trials at the fastest rates, “possibly in association with more efficient trial startup processes and higher recruitment rates.”

Median time to trial completion differed substantially by sponsor type, the study showed, with NIH and government-funded trials decreasing to 3.4 years (down from 5.4 years), and 2.1 years for other sponsors (down from six years in 2000).

The number of trials involving drugs also decreased over time, which the researchers reasoned could be due to the increasing costs and complexity involved in late-stage drug trials. Additionally, the overall percentage of drug trials that were completed decreased sharply in the 19-year timeframe. From 2000-2004, 70.5 percent of trials crossed the finish line; but that number dropped to 61.8 percent between 2005-2009, 48.9 percent from 2010-2014, and 40 percent between 2015-2019.

“These trends are reflected in the decreasing number of phase 1 to 2 and phase 3 to 4 trials being completed and the increasing number of trials lacking an FDA-defined phase,” the researchers wrote. They added that increasing interest in other types of interventions — medical devices, biologics, imaging and behavioral interventions — may have also played a part in the decrease in drug trials.

Most of the completed trials in the CT.gov study across all three sponsor types were single center (61.3 percent) and randomized (65.6 percent), and just over one-third of the trials were phase 1 to 2 (35.5 percent) or had no FDA-defined phase (38.4 percent).

To read the report, click here: https://bit.ly/32IpS9W.