Clinical Trials in Gastroesophageal Cancers: An Analysis of the Global Landscape of Interventional Trials From ClinicalTrials.gov.

PURPOSE

To describe the global landscape of clinical research into interventions for gastroesophageal cancers (GECs), with examination of trial characteristics, geographic distribution of trial sites, and factors associated with trial termination.

METHODS

We queried ClinicalTrials.gov to identify all completed or terminated phase III interventional studies investigating GECs (esophageal squamous cell carcinoma [ESCC], esophageal adenocarcinoma [EAC], gastroesophageal junctional [GEJ], and gastric adenocarcinoma). Data on all reported trial characteristics were extracted. Pearson's chi-square and Fisher's exact tests were used to compare differences in completed and terminated trials. Multivariate logistic regression evaluated predictors of termination.

RESULTS

A total of 179 trials were identified; of these, 90% were therapeutic. Most included sites in Asia (61%) and Europe (32%); few included sites in Africa (4%). Thirty percent included sites in low- and middle-income countries (LMICs). Most (70%) focused on gastric or GEJ adenocarcinoma, 13% on EAC and ESCC, and 9% on ESCC alone. Sixteen percent (n = 29) of trials terminated prematurely. In multivariate analysis, study site number, location of recruitment sites, and patient population emerged as predictors of termination. Trials recruiting from US-based sites were more likely to terminate (odds ratio [OR], 7.22 [95% CI, 1.59 to 32.69]). Trials conducted exclusively in LMICs were less likely to terminate (OR, 0.04 [95% CI, 0.01 to 0.59] conducted in high-income countries [HICs] alone). Studies on ESCC were more likely to terminate (OR, 17.74 [95% CI, 1.49 to 210.69]).

CONCLUSION

Although 80% of GECs occur in LMICs, trial activity disproportionately occurs in HICs. Few trials focus on EAC/ESCC despite being highly fatal, highlighting an unmet need. Overall, this study highlights (1) a missed opportunity to recruit patients from high-incidence regions globally; and (2) a pressing need for increasing funding, infrastructure, and support for GEC trials in LMICs.