Tolerance Bio has vaulted into the clinic by agreeing to pay NeoImmuneTech up to $260 million for rights to a fusion protein in certain thymus-related indications in the Americas and Europe.
Philadelphia-based Tolerance launched in October 2024 with $17.2 million in seed funding and plans to treat immune-mediated diseases by targeting the thymus. Because the thymus regulates and develops T cells and becomes less active as people age, researchers have identified the organ as a way to treat a range of diseases. In July, United Therapeutics paid $140 million for a thymic cell therapy startup.
Tolerance Bio has identified NeoImmuneTech’s long-acting IL-7 fusion protein efineptakin alfa as a good fit for its ambitions. NeoImmuneTech and its partners have primarily studied the drug candidate, which is also called NT-I7, in blood cancers, but Tolerance sees other applications for the fusion protein.
The biotech plans to run phase 2 trials testing the ability of efineptakin alfa to enhance thymic function. HIV immunological non-response is among the initial indications on Tolerance’s roadmap. Seeing HIV immunological non-response as a model of accelerated immune aging, the biotech could leverage success in this indication to inform development of additional thymus-related conditions.
Tolerance has secured rights to efineptakin alfa in the indications in return for a financial package that features an equity consideration, up to $260 million in development and sales milestones and tiered royalties on net sales.
The biotech’s interest in the asset is underpinned by evidence that IL-7 stimulates thymic function and T cell differentiation, proliferation and survival. Interest in IL-7’s effect on the thymus goes back decades, and in the early 2000s, the link fueled enthusiasm for the clinical development of the cytokine, leading to trials in indications including HIV and cancer.
NeoImmuneTech has worked to realize the potential of IL-7 by engineering the cytokine to improve its half-life, structural stability, bioavailability and potency. Investigators continue to test the drug candidate in blood cancer patients.