Underrepresented groups with cystic fibrosis less likely to be eligible for CFTR modulators

Patients from minority racial and ethnic groups with cystic fibrosis are less likely to be eligible for cystic fibrosis transmembrane conductance regulator modulators, according to findings published in Pediatric Pulmonology.

“In this cross-sectional study, we found that patients of a minority group with [cystic fibrosis] were less likely to have CFTR genotypes eligible for disease-altering CFTR modulator therapies compared to non-Hispanic white patients. The lowest percentages in patients with CFTR genotypes eligible for any CFTR modulator were seen in Black, Hispanic and other race patients. Only two-thirds of Black and Asian patients and three-quarters of Hispanic patients had CFTR genotypes eligible for a CFTR modulatory therapy compared to over 90% of non-Hispanic white patients,” Meghan E. McGarry, MD, assistant professor in the department of pediatrics at the University of California, San Francisco, and colleagues wrote. “This pattern was true for all CFTR modulator therapies.”

The study included all patients from the 2018 CF Foundation Patient Registry, which includes 81% to 84% of U.S. patients with cystic fibrosis. Of those, 25,918 (84.2%) were non-Hispanic white, 1,351 (4.4%) were Black/African American, 2,763 (9%) were Hispanic and 743 (2.4%) were other races. Researchers analyzed the percentage of patients in each racial and ethnic group eligible for CFTR modulators based on approved FDA CFTR mutations followed by an analysis based on mutations and FDA approval by age.

Researchers identified 92.4% of non-Hispanic white patients, 69.7% of Black/African American patients, 75.6% of Hispanic patients and 80.5% of other race patients eligible for CFTR modulators based on CFTR mutations alone.

For ivacaftor (Kalydeco, Vertex Pharmaceuticals), only 11.4% of Black/African American patients were eligible compared with other races and ethnicities (P < .001). Researchers observed lower percentages of Black/African American patients, Hispanic patients and other race patients eligible for lumacaftor/ivacaftor therapy (Orkambi, Vertex; 19.2%, 24% and 31.6%, respectively), tezacaftor/ivacaftor therapy (Symdeko, Vertex; 21.5%, 29.8% and 35.9%, respectively) and elexacaftor/tezacaftor/ivacaftor therapy (Trikafta, Vertex; 62.5%, 67.3% and 71.9%, respectively) compared with non-Hispanic white patients (47.9%, 53.9% and 88%; P < .001 for all), according to the results.

Lowest pulmonary function measured by FEV1 was observed among non-Hispanic white patients (75.6%), Black/African American patients (77.6%) and Hispanic patients (78.8%) not eligible for CFTR modulators.

With the addition of current FDA approval by age, there was no difference between racial and ethnic group disparity, according to the results.

“These findings are alarming as patients of a minority group already suffer a greater burden from cystic fibrosis compared to non-Hispanic white patients,” the researchers wrote. “If a higher percentage of non-Hispanic white patients are on CFTR modulator therapy than patients of a minority group, the disparity will widen. These patients are in high need of the therapeutic benefits to pulmonary function that high-efficacy modulators provide.”