A patient advocacy group sued the National Institutes of Health over its intention to grant Gilead an exclusive license for its experimental CAR-T cell therapy.

The advocacy group, Knowledge Ecology International, claimed the experimental cancer treatment’s high drug price could exclude many patients from gaining access to the drug and place “severe burdens” on consumers, patients, taxpayers and health budgets.

The exclusive license involves a set of patent applications regarding the development of the medicine, a CAR-based immunotherapy using autologous T-cells for treating certain types of lymphoma.