Timeliness of completion of NCI cooperative group trials.

490 Background: In response to efficiency concerns, the NCI cooperative group trial system was redesigned in 2014 to streamline trial design and conduct. As timely evidence is vital to high-quality cancer care, we examined trial accrual and timeliness in recent NCI cooperative group trials, focusing on meeting accrual targets and time to completion. Methods: We used the Aggregate Analysis of ClinicalTrials.gov (AACT) database to identify phase II or III interventional trials that were initiated between 2011 and 2019 and had an NCI cooperative group listed as the sponsor, responsible party, or principal investigator. To assess a study’s time to completion, we quantified the time between its “start date” and “primary completion date” (date when the final data to fulfill the primary outcome were ascertained) listed on ClinicalTrials.gov. The primary outcome was trial primary completion within 5 years of initiation (for trials initiated before 2019); we also assessed 8-year trial completion (for trials initiated prior to 2016). To examine the timeliness of recent NCI cooperative group trials, we used chi-square tests and adjusted logistic regressions to compare the five-year completion status of trials initiated in 2011–2013 (T1: prior to the 2014 redesign of the National Clinical Trials Network (NCTN)) versus 2016–2018 (T2: after NCTN redesign), adjusting for trial phase and cancer type. A subgroup analysis was conducted among phase III trials. Results: We included 323 studies, and 196 were classified as phase II, 17 were phase II/III, and 110 were phase III. Hematologic (n=49), breast (n=36), and non-small cell lung (n=39) were the most common cancer types researched. NRG Oncology (n=75), Alliance for Clinical Trials in Oncology (n=64), and Eastern Cooperative Oncology Group (n=61) were the most represented cooperative groups. Overall, 40 studies had a final study status of either terminated (0.8%), withdrawn (0.2%), or unknown (0.2%). 50.2% of studies reached their primary outcome within five years (24.5% of phase III and 62.2% of phase II trials). Among the 194 studies initiated prior to 2016, 147 (75.8%) were completed at 8 years (60% of the 70 phase III trials; 84.8% of the 112 phase II trials). Of the 2011–2013 (T1) trials (n=119), 5-year completion status was 46.2%, compared to 58.9% of the 95 studies in T2 (p=0.09). Among phase III trials, the 5-year completion status was 25.6% (T1) and 28.5% (T2) (p=1.00). Adjusting for trial phase and cancer type, there was no significant association between time period and five-year completion status (Odds ratio for T2 vs T1: 1.27; 95% CI: 0.66 to 2.48). Conclusions: Half of NCI cooperative group trials reached primary completion within 5 years, with only one quarter of phase III trials completed in this same time frame. There was no significant improvement in time to completion of phase III trials after the 2014 NCTN redesign, although the COVID epidemic may have hampered trial conduct during the latter time period.