Social determinants of health affect the outcomes of many illnesses, and pediatric cancer is not any exception. In reality, children with acute lymphoblastic leukemia (ALL) living in poverty are significantly more prone to relapse and die from their disease than those from wealthier backgrounds. While socioeconomic status often influences survival outcomes, children with relapsed/refractory ALL treated with CAR T-cell therapy living in poverty are equally prone to achieve overall survival as children from more socioeconomically advantaged households, in keeping with a study published today in Blood.

CAR T-cell therapy is a sort of immunotherapy by which a patient’s T-cells, immune cells within the body that fight infection, are removed, genetically modified in a laboratory to assist them discover and goal cancer cells, after which infused back into the patient’s bloodstream where they find and destroy cancer cells. This therapy has been shown to achieve success in improving outcomes for those with ALL, yet it could be expensive, time-intensive, and largely out of reach for a lot of marginalized groups.

Further, some researchers argue that because marginalized groups have lower overall survival rates, they could be less prone to fare well with CAR T-cell therapy. Nonetheless, the outcomes of this recent Blood study may change this narrative.

What we see here is that amongst this cohort, CAR T-cell therapy is equally effective no matter poverty exposure. This study suggests that CAR T-cell therapies work equivalently.”

Haley Newman, MD, a fellow in pediatric oncology within the division of oncology and cancer immunotherapy program, Kid’s Hospital of Philadelphia (CHOP)

Dr. Newman and colleagues studied the outcomes of 206 children and young adults treated at CHOP, with a median age of 12.5 years with reduced/refractory ALL treated on one in all five CD19-directed CAR T-cell clinical trials or with a industrial CAR-T, tisagenlecleucel. They collected data from CAR T-cell clinical trial datasets and electronic medical records from patients treated between April of 2012 and December of 2020. Researchers then sorted patients by socioeconomic and neighborhood opportunity exposures, which they determined using insurance types and patient addresses.

Children with public insurance coverage were considered household-poverty exposed, while those with private or industrial insurances weren’t. Researchers used a census tract-based multidimensional quality measure of US neighborhood metrics to find out neighborhood opportunity, or the access a household has to resources that influence kid’s health and development, based on where patients were living.

“Many previous neighborhood studies have sorted data on the zip code level. We actually had address data for these patients, which allowed us to geocode their census tract, which is the extent at which the childhood opportunity index is measured,” explained Dr. Newman.

Results revealed no significant difference in overall survival or complete remission rates between household-poverty exposed patients with lower neighborhood opportunity and people from more advantaged households (unexposed to household poverty or living in high opportunity neighborhoods).

Interestingly, the information also demonstrated that children from more advantaged households were significantly more prone to present with high disease burden on the time of referral for CAR T-cell infusion. Because high-disease burden is related to inferior outcomes and greater risks for toxicity, those presenting with severe types of disease are generally considered at greater risk with CAR T-cell treatment.

Dr. Leahy, an oncologist within the division of oncology at CHOP, explains that while we all know patients with higher disease burdens are generally sicker, the information suggest that those from more advantaged households with high disease burdens are still being referred for CAR T-cell therapy, while those from lower socioeconomic groups will not be referred or can have more challenges to advocating for a similar treatment.

“We will not say exactly why we’re seeing a difference in disease burden, nevertheless it may very well be because of provider referral biases, families from more advantaged households having more resources to access CAR-T and more flexibility to take time without work work for treatments, or there could also be a difference in how families are capable of advocate for his or her children to receive this therapy,” explained Dr. Leahy.

While these results provide each hope and evidence to extend access to CAR-T for those from disadvantaged households, investigators still voice the importance of replicating these findings in larger populations outside of clinical trial settings. Dr. Newman noted that this study incorporates data from a single center, so its results can’t be generalized to populations outside of the CHOP community.

“This study shows us that patients from disadvantaged households do well with CAR T-cell therapy,” said Dr. Newman. “To me, that claims that we’d like to make this therapy more accessible, whether that be through recent interventions, or providing more resources for families, like transportation and funding for medical leave.”

Source:

American Society of Hematology

Journal reference:

Newman, H., et al. (2022) Impact of poverty and neighborhood opportunity on outcomes for kids treated with CD19-directed CAR T-cell therapy. Blood. doi.org/10.1182/blood.2022017866.