Social determinants of health influence the outcome of many diseases and childhood cancer is no exception. In fact, children with acute lymphoblastic leukemia (ALL) who live in poverty have a significantly higher risk of relapsing and dying from their disease than children from wealthier backgrounds. While socioeconomic status often influences survival outcomes, children with relapsed/refractory ALL treated with CAR-T cell therapy and living in poverty are just as likely to achieve overall survival as children from wealthier households, according to a study published today in study blood.
CAR-T cell therapy is a type of immunotherapy in which a patient’s T cells, immune cells in the body that fight infection are removed, genetically modified in a laboratory to help them identify and fight cancer cells, and then infused back into the patient’s bloodstream, where they find and destroy cancer cells. This therapy has proven successful in improving outcomes for people with ALL, but it can be expensive, time-consuming, and largely unattainable for many marginalized groups.
Additionally, some researchers argue that marginalized groups may be less able to cope with CAR-T cell therapy due to lower overall survival rates. However, the results of this new blood Study can change that narrative.
What we see here is that in this cohort, CAR-T cell therapy is equally effective regardless of poverty risk. This study suggests that CAR-T cell therapies are equivalent.”
Haley Newman, MD, Pediatric Oncology Fellow in the Department of Oncology and Cancer Immunotherapy Program, Children’s Hospital of Philadelphia (CHOP)
dr Newman and colleagues examined the outcomes of 206 CHOP-treated children and young adults with a mean age of 12.5 years with reduced/refractory ALL who were in one of five CD19-targeted CAR T-cell clinical trials or who had a commercial CAR -T, Tisagenlecleucel. They collected data from clinical CAR-T cell datasets and electronic medical records from patients treated between April 2012 and December 2020. The researchers then sorted the patients according to socioeconomic and neighborhood opportunities, which they determined based on insurance types and patient addresses.
Children with statutory health insurance were considered to be affected by household poverty, while children with private or commercial insurance were not. Researchers used a census district-based multidimensional quality measure of US neighborhood metrics to determine a household’s neighborhood opportunities, or a household’s access to resources that affect child health and development, based on the patient’s location.
“Many previous neighborhood studies sorted data at the zip code level. We actually had address data for these patients that allowed us to geocode their census district on which the Childhood Chances Index is measured,” explained Dr. newman .
The results showed no significant difference in overall survival or complete remission rate between patients exposed to household poverty and fewer neighborhood opportunities and patients from better-off households (those not exposed to household poverty or living in neighborhoods with good opportunities) .
Interestingly, the data also showed that children from wealthier households were significantly more likely to have a high disease burden at the time of referral for CAR T-cell infusion. Because a high burden of disease is associated with poorer outcomes and greater risk of toxicity, patients with severe disease are generally considered to be at higher risk for CAR-T cell treatment.
dr Leahy, an oncologist in CHOP’s Division of Oncology, explains that while we know that patients with a higher burden of disease are generally sicker, the data suggest that patients from wealthier households with a high burden of disease are still more likely to T cells are referred for therapy, while people from lower socioeconomic groups may not be referred or may have more difficulty advocating for the same treatment.
“We can’t say exactly why we’re seeing a difference in disease burden, but it could be due to bias in provider referral, families from more privileged households with more resources to access CAR-T, and more flexibility in taking time off from the work or there may be a difference in how families can advocate for their children to receive this therapy,” explained Dr. Leahy.
While these results offer both hope and evidence for improved access to CAR-T for individuals from disadvantaged households, the researchers continue to emphasize the importance of replicating these results in larger populations outside of clinical trial settings. dr Newman noted that this study contains data from a single center, so its results cannot be generalized to populations outside of the CHOP community.
“This study shows us that patients from disadvantaged households are doing well with CAR-T cell therapy,” said Dr. newman “To me, that means we need to make this therapy more accessible, whether that’s through new interventions or by providing more resources for families, like transportation and funding for sick leave.”
American Society of Hematology
Neumann, H. et al. (2022) Impact of neighborhood poverty and opportunity on outcomes for children treated with CD19-targeted CAR-T cell therapy. Blood. doi.org/10.1182/blood.2022017866.