New Dual-Action Autoimmune Drug Enters Human Trials

NANJING, China, NEW YORK & WALTHAM, Mass. – December 23, 2025 – A promising new chapter in the fight against complex autoimmune diseases has begun as biotechnology firms Leads Biolabs and Dianthus Therapeutics announced the first patient has been dosed in a Phase 1 clinical trial for a novel investigational therapy, LBL-047, also known as DNTH212.

The trial, which will evaluate the drug in both healthy volunteers and patients with systemic lupus erythematosus (SLE), marks a critical first step for a therapy designed with a unique, two-pronged approach to reining in a dysfunctional immune system. The successful dosing represents a key milestone in a global partnership potentially worth up to $1 billion between China-based Leads Biolabs and U.S.-based Dianthus Therapeutics.

A Two-Pronged Attack on Autoimmunity

At the heart of the excitement surrounding LBL-047 is its sophisticated design as a bifunctional fusion protein. Unlike many existing treatments that target a single aspect of the immune cascade, this therapy is engineered to simultaneously address both the innate and adaptive immune systems, the two major arms of the body's defense network that become misguided in autoimmune conditions.

The drug targets two clinically validated pathways known to be drivers of autoimmune disease. First, it targets BDCA2, a protein found on plasmacytoid dendritic cells (pDCs). These cells are key players in the innate immune system and act as factories for Type 1 interferons, signaling molecules that are notoriously overproduced in diseases like lupus, leading to widespread inflammation and tissue damage. By targeting BDCA2, LBL-047 aims to deplete these pDC cells and dramatically reduce interferon production.

Simultaneously, the therapy inhibits the activity of two other crucial molecules: BAFF (B-cell activating factor) and APRIL (a proliferation-inducing ligand). These are essential for the survival and maturation of B cells, the adaptive immune cells responsible for producing antibodies. In autoimmune diseases, B cells mistakenly create autoantibodies that attack the body's own tissues. By neutralizing BAFF and APRIL, LBL-047 is designed to suppress this harmful B cell activity. This complementary mechanism has the potential to deliver a more comprehensive and powerful therapeutic effect than single-target approaches.

The Clinical Pathway and Billion-Dollar Partnership

The Phase 1 trial is a meticulously designed, two-part study. Part A, a double-blind, randomized, placebo-controlled, single ascending dose portion, will enroll healthy volunteers to primarily assess the drug's safety, tolerability, and pharmacokinetic profile. This part of the study is being led by Professor Meng Xianmin at the Shanghai Public Health Clinical Center. Part B will move into patients with SLE to gather early data in the target population, under the guidance of Professors Ye Shuang and Chen Sheng at the renowned Renji Hospital, Shanghai Jiaotong University School of Medicine.

This clinical advancement is the first major step under a landmark strategic partnership formed in October 2025. Under the agreement, Leads Biolabs granted Dianthus Therapeutics exclusive global rights to develop, manufacture, and commercialize the drug—referred to as DNTH212 by Dianthus—everywhere outside of Greater China. The deal structure, with a total potential value reaching up to $1 billion, underscores the high expectations for the therapy's clinical and commercial future.

Investors and patients are now looking toward key upcoming dates. Dianthus expects to provide an update on which other autoimmune indications it will prioritize for development in the first half of 2026, while top-line results from the healthy volunteer portion of the current Phase 1 trial are anticipated in the second half of 2026.

Patient-Centric Design and Market Potential

Beyond its novel mechanism, LBL-047 has been engineered with the patient experience firmly in mind. The developers have optimized the molecule with Fc engineering, a technique used to extend its half-life in the body. This is crucial for creating a more convenient treatment regimen.

The ultimate goal is to offer the drug as a patient-friendly, subcutaneous self-injection that needs to be administered only once every four weeks (Q4W) or even less frequently. This would represent a significant improvement in quality of life compared to more frequent injections or time-consuming intravenous infusions required for some current biologics.

This convenience, combined with its potent dual-action mechanism, supports the drug's potential to become a first-line biologic. This means it could be prescribed early in the course of the disease for a wide range of patients, not just reserved for those who have failed other treatments. If successful, it could position LBL-047 (DNTH212) as a transformative option in a crowded but innovation-hungry market for autoimmune therapies.

“We are pleased to announce the successful dosing of the first subject in our Phase 1 trial of LBL-047,” stated Dr. Charles Cai, Chief Medical Officer of Leads Biolabs. “By simultaneously targeting multiple pathways, LBL-047 is designed to address the limitations of single-target therapies. We look forward to advancing this program in collaboration with Dianthus Therapeutics to deliver potentially transformative options for patients worldwide.”

Dr. Simrat Randhawa, Head of Research & Development at Dianthus Therapeutics, echoed the optimism, highlighting the significance of this milestone for the medical community. “Initiating this Phase 1 study is the first step to realizing the much anticipated by physicians outcome of targeting multiple pertinent dysfunctional pathways in several autoimmune indications.”