Deerfield-Designed Precision Immunology Startup

Boulevard Bio emerges from stealth mode with $65 million in seed funding from Deerfield Management. The company has established three candidates targeting B-cell-mediated autoimmune diseases, and the initial funding will be used for preclinical validation and clinical entry. A key aspect is its focus on an 'immune reset' strategy that regulates B cells and antibody-secreting plasma cells, rather than concentrating on a single indication. As a private company, this funding should be viewed as a venture incubation investment from Deerfield, rather than a public market raise.

MTS-128 as a Strategic Pipeline Asset

MTS-128, developed by METiS TechBio, is a preclinical trispecific T-cell engager (TCE) that simultaneously targets CD19, BCMA, and CD3. It aims to eliminate CD19-positive B cells and BCMA-positive plasma cells by engaging the patient's CD3-positive T cells, thereby broadly reducing the source of autoantibody production. METiS's Hong Kong Stock Exchange listing document presented data from non-human primates showing deep depletion of B cells and plasma cells in peripheral blood and lymphoid tissues, along with favorable safety signals. However, efficacy data in humans has not yet been generated. Therefore, its current value relies on its design advantages in controlling tissue penetration, cytokine release syndrome (CRS), and the risk of infection, rather than clinical efficacy.

Up to $1.62 Billion in Back-End Loaded Deal

Boulevard entered into an agreement with METiS TechBio (7666.HK) on June 30, 2026, to pay a $20 million upfront payment for the global development, manufacturing, and commercialization rights to MTS-128. The deal includes development, regulatory, and sales milestones of up to $1.6 billion, with additional tiered royalties based on sales, bringing the maximum potential value to $1.62 billion. The $20 million upfront payment represents only about 1.2% of the total potential value, with the majority of the clinical and regulatory risks placed in the back-end payments. This structure allows Boulevard to secure a key asset while limiting cash burn, and provides METiS with an external validation of its NanoForge-based protein design.

Competition Already in Clinical Stages

The direct competitor, KT501, is a CD19/BCMA/CD3 trispecific TCE that has entered Phase 1 clinical trials for rheumatoid arthritis, and Sanofi (SNY) secured global rights in March 2026. Antengene (6996.HK)'s CD19xCD3 candidate, ATG-201, has also entered clinical development for autoimmune diseases, and CD20xCD3 candidates like PRO-203 are competing in early clinical trials. MTS-128 is still in the preclinical stage and has no FDA, EMA, or PMDA approvals or advisory committee (AdComm) history. It is also behind the leading candidates in terms of clinical entry. However, its targeting of both CD19 and BCMA, aiming to eliminate both mature B cells and long-lived plasma cells, differentiates it from single B-cell target candidates.

Market Potential is Large, but Safety is Key

The global market for autoimmune disease therapies is projected to grow from $80.54 billion in 2025 to $137.85 billion in 2035, according to SNS Insider. Current standard treatments consist of corticosteroids, JAK inhibitors, TNF inhibitors, and B-cell therapies like rituximab, but these treatments have limitations in terms of long-term immunosuppression and the risk of relapse. TCEs have the advantage of being readily available, unlike CAR-T therapies that require custom manufacturing, but the management of CRS, hypogammaglobulinemia, and infection are key challenges for commercialization. The $65 million in funding provides a foundation for advancing into early clinical trials, but the re-evaluation of MTS-128's investment value will begin with the first human administration and pharmacokinetic data on B-cell depletion.