Efineptakin alfa (Genexine)

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.

TLB-33 adds a complementary mechanism and further expands Tolerance Bio’s clinical-stage pipeline targeting thymic biology Company planning Phase 2 clinical development beginning in 2027 as it builds a pipeline of complementary modalities to improve thymic function for better healthspan PHILADELPHIA--(BUSINESS WIRE)--Tolerance Bio, Inc. (“Tolerance Bio” or the “Company”), a biotechnology company focused on preserving, regenerating and modulating thymic function to address immune diseases and extend healthspan, today announced an exclusive license agreement across all indications with Tanabe Pharma Corporation (“Tanabe Pharma”) granting Tolerance Bio worldwide development rights and exclusive commercialization rights outside Japan for MT-2990, now TLB-33, a clinical-stage anti-IL-33 monoclonal antibody. Tanabe Pharma retains commercialization rights in Japan. Tolerance Bio is among the first companies specifically targeting thymic biology as a therapeutic strategy to preserve immune resilience and is uniquely positioned with a clinical-stage, multi-modality pipeline focused on thymic function. This agreement further expands the Company’s clinical-stage pipeline, following the recently announced licensing of NeoImmuneTech’s long-acting interleukin 7 (IL-7), efineptakin alfa . Tolerance is preparing to advance TLB-33 into Phase 2 clinical development to evaluate its potential to preserve thymic function and enhance immune resilience, with additional immune indications also under consideration. The Company also expects to announce the completion of a financing round to support the advancement of TLB-33 and efineptakin alfa through planned clinical trials. The addition of TLB-33 broadens Tolerance Bio’s pipeline across therapeutic modalities focused on thymus biology, including biologics, mRNA and cell therapies. 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. TLB-33 has been evaluated in over 150 subjects across multiple clinical studies, providing substantial human safety and proof-of-biological principle data that strongly supports further clinical development in new indications such as thymic preservation. Tolerance Bio’s management team brings significant experience identifying, repositioning and advancing clinical-stage assets in new indications, including at Celimmune and Provention Bio. “This agreement represents another important milestone for Tolerance Bio as we continue to build a clinical-stage pipeline around complementary approaches to thymic biology,” said Francisco Leon, MD, PhD, Chief Executive Officer of Tolerance Bio. “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,” Leon continued. “IL-33 signaling has been implicated in thymic involution in inflammatory settings, and we believe that blocking IL-33 offers an opportunity to preserve thymic function and improve immune resilience. Together with our recently licensed long-acting IL-7 program, TLB-33 gives us complementary approaches to preserving and restoring thymic function.” Under the terms of the agreement, Tanabe Pharma has granted Tolerance Bio exclusive rights to develop and manufacture TLB-33 worldwide across all indications and to commercialize it outside Japan. Tanabe Pharma retains commercialization rights in Japan. The license includes potential development and sales milestone payments of up to approximately $560 million, as well as equity consideration and tiered royalties on net sales. About TLB-33 (MT-2990) and the thymus TLB-33/MT-2990 is a clinical-stage human immunoglobulin G1 (IgG1) monoclonal antibody that binds to and neutralizes interleukin-33 (IL-33). IL-33 is an alarmin released upon cellular stress or tissue injury that drives activation of innate and adaptive immune responses. Dysregulated IL-33 signaling has been implicated in inflammatory pathways believed to contribute to thymic dysfunction and the progressive decline of immune function with age as well as acute thymic involution in certain immune conditions. TLB-33 has been evaluated in over 150 subjects across five clinical studies. The safety, tolerability, pharmacologic and clinical data generated to date support clinical development in new indications aligned with Tolerance Bio’s strategy. The thymus plays a central role in T-cell maturation and immune competence, but progressively involutes with age and in the context of acute inflammatory triggers. This decline contributes to increased susceptibility to infections, cancer, autoimmunity and reduced vaccine responsiveness. The Company is advancing TLB-33 to evaluate its potential to preserve thymic output and enhance immune resilience, with additional development planned in certain immune diseases. About Tolerance Bio Tolerance Bio is a biotechnology company focused on preserving, regenerating and modulating thymic function to address immune diseases and extend healthspan. The Company is developing a pipeline of therapies targeting thymus biology, including biologics, thymus-targeted mRNA and thymus cell therapies. Tolerance Bio is backed by leading life-sciences investors, including Columbus Venture Partners, Criteria Bio Ventures, Pacific 8 Ventures, and BioAdvance Capital. Learn more at About Tanabe Pharma Tanabe Pharma Corporation is a Japan-focused, innovation-driven pharmaceutical company guided by its mission, "Creating hope for all facing illness." Founded in 1678, the company is one of Japan's oldest pharmaceutical companies and is committed to addressing unmet medical needs through R&D, business development, and strategic partnerships with the aim of improving the lives of patients. For more information, visit Contacts Media Contact Amy Wheeler-Garcia iecommstolerance@inizioevoke.com