Social vulnerability and clinical trial access for older adults with myeloma in North Carolina.

Abstract

e18540 Background: Multiple myeloma (MM) is a disease of aging, associated with one of the greatest black-white disparities in incidence and mortality among all US cancer types. Clinical trials provide the critical evidence-base to inform clinical management in all cancers, including MM. However, clinical trial participants are often younger (age < 65 years) and white, limiting the generalizability of published data to real-world MM care. Although geographical and financial barriers to clinical trial participation are well recognized, less is known about the association of county-level social vulnerability with MM trial availability. We examined county-level variation in the number of registered myeloma trials per 10,000 North Carolina (NC) residents age ≥ 65 years as a function of social vulnerability and the presence of a National Cancer Institute Comprehensive Cancer Center (CCC). Methods: We conducted a cross-sectional study using data from ClinicalTrials.gov to identify all registered interventional myeloma trials involving adults age ≥ 65 years with sites in NC. Records were downloaded on January 24th, 2021. This strategy yielded 456 non-unique NC sites for 223 trials. We obtained county locations for all trial sites by matching city, zip code, or institution name. We obtained NC population data for residents age ≥ 65 years (in 2019) from the American Community Survey. The four themes (socioeconomic status, household composition, ethnic and racial minority status/language, housing/transportation) within the Centers for Disease Control Social Vulnerability Index (CDC SVI) (composite score: 0-1, with a higher number indicating more vulnerability) were used to characterize county-level social vulnerability. We performed negative binomial regression and tabulations using R, version 3.6.1. A p-value < 0.05 was considered statistically significant. Results: Across 100 counties in NC, trial site counts by county per 10,000 residents age ≥ 65 years ranged from 0 to 23.2 (mean: 1.5, median: 0; IQR, 0-0.7). Controlling for the 4 SVI themes, counties with CCCs (Durham, Forsyth, Orange) had 77% more trials than those without CCCs [Incidence Rate Ratio (IRR): 7.74; p = 0.05]. We observed a 3.3% reduction in trial counts with each percentile increase in socioeconomic vulnerability (IRR: 0.97; p = 0.008). Counties with higher representation by racial and ethnic minorities had similar trial site counts to counties with lower minority populations (IRR: 1.01; p = 0.08). Sub-group analyses of early-stage studies (phase 1/2 and phase 2; n = 268) and late-stage studies (phase 2/3 and phase 3; n = 168) were similar. Conclusions: Our preliminary results suggest county-level socioeconomic status is associated with the distribution of MM clinical trial sites across NC. Further work is planned to explore whether additional variances in trial distribution could be explained by site- and study-specific characteristics.