On September 28, 2026 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, reported 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.

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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.

(Press release, Tolerance Bio, SEP 28, 2026, View Source [SID1234671126])