Temporal Trends and Predictors for Cancer Clinical Trial Availability for Medically Underserved Populations

Abstract

Background. Lack of access to available cancer clinical trials has beencited as a key factor limiting trial accrual, particularly amongmedically underserved populations. We examined the trends and factors inclinical trial availability within a major U.S. safety-net hospitalsystem.Materials and Methods. We identified cancer clinical trials activated atthe Harold C. Simmons Cancer from 1991 to 2014 and recorded thecharacteristics of the trials that were and were not activated at theParkland Health and Hospital System satellite site. We used univariateand multivariate logistic regression to determine the associationbetween trial characteristics and nonactivation status, and chi-squareanalysis to determine the association between the trial characteristicsand the reasons for nonactivation.Results. A total of 773 trials were identified, of which 152 (20%) werenot activated at Parkland. In multivariable analysis, nonactivation atParkland was associated with trial year, sponsor, and phase. Comparedwith the 1991-2006 period, clinical trials in the 2007-2014 period werealmost eightfold more likely not to be activated at Parkland. The mostcommon reasons for nonactivation at Parkland were an inability toperform the study procedures (27%) and the startup costs (15%).Conclusion. Over time, in this single-center setting, a decreasingproportion of cancer clinical trials were available to underservedpopulations. Trial complexity and costs appeared to account for much ofthis trend. Efforts to overcome these barriers will be key to equitableaccess to clinical trials, efficient accrual, and the generalizabilityof the results.