After vaulting into the clinic by licensing a fusion protein last month, Tolerance Bio has continued to strengthen its thymus-focused pipeline by picking up an anti-IL-33 drug from Tanabe Pharma.
The deal will see Tolerance secure the rights to the human immunoglobulin G1 (IgG1) anti-IL-33 monoclonal antibody, formerly called MT-2990, outside of Tanabe’s home turf of Japan. The agreement includes milestone payments that could potentially reach $560 million, although the companies didn’t offer a breakdown of the financials.
Tanabe has already evaluated the asset, to be renamed TLB-33, in over 150 patients spanning five clinical trials. The plan is for Tolerance to take TLB-33 into a phase 2 study to see if the therapy can preserve thymic function and enhance immune resilience, as well as explore its potential for other immune indications.
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.
Last month, the biotech agreed to a $260 million deal with NeoImmuneTech for its long-acting IL-7 fusion protein efineptakin alfa. That agreement was underpinned by evidence that IL-7 stimulates thymic function and T cell differentiation, proliferation and survival.
IL-33 signaling has also been implicated in thymic involution in inflammatory settings, Tolerance pointed out in today’s release. The biotech is betting that by blocking IL-33, Tanabe’s drug can preserve thymic function and improve immune resilience.
“TLB-33 is a well-characterized clinical-stage antibody with substantial human safety and pharmacologic data, and its development builds on our team’s experience repositioning clinical-stage assets in high-value new indications,” Tolerance CEO Francisco Leon, M.D., Ph.D., said in a Sept. 28 release.
“Together with our recently licensed long-acting IL-7 program, TLB-33 gives us complementary approaches to preserving and restoring thymic function,” Leon added.
The company is planning to bankroll phase 2 plans for both TLB-33 and efineptakin alfa via an upcoming financing round.
“Together, these programs are designed to preserve, regenerate and modulate thymic function and collectively position the company to build the leading therapeutic platform targeting thymic biology,” Tolerance explained.