Temporal trends and predictors for cancer clinical trial availability for medically underserved populations

Background. Lack of access to available cancer clinical trials has been cited as a key factor limiting trial accrual, particularly among medically underserved populations. We examined the trends and factors in clinical trial availability within a major U.S. safety-net hospital system. Materials and Methods.We identified cancer clinical trials activated at the Harold C. Simmons Cancer from 1991 to 2014 and recorded the characteristics of the trials that were and were not activated at the Parkland Health and Hospital System satellite site. We used univariate and multivariate logistic regression to determine the association between trial characteristics and nonactivation status, and chi-square analysis to determine the association between the trial characteristics and the reasons for nonactivation. Results. A total of 773 trials were identified, of which 152 (20%) were not activated at Parkland. In multivariable analysis, nonactivation at Parkland was associated with trial year, sponsor, and phase. Compared with the 1991-2006 period, clinical trials in the 2007-2014 period were almost eightfold more likely not to be activated at Parkland. The most common reasons for nonactivation at Parkland were an inability to perform the study procedures (27%) and the startup costs (15%). Conclusion. Overtime, in this single-center setting, a decreasing proportion of cancer clinical trials were available to underserved populations. Trial complexity and costs appeared to account for much of this trend. Efforts to overcome these barriers will be key to equitable access to clinical trials, efficient accrual, and the generalizability of the results. Disclosures of potential conflicts of interest may be found at the end of this article.