Adagene closes $28 million Series B to scale antibody discovery platforms

Adagene said today it has closed a $28 million Series B financing to accelerate its therapeutic antibody discovery and engineering platforms and to advance preclinical programs into human trials. The Suzhou-based company said the proceeds “will be used to advance novel antibody therapeutics into human trials across the globe,” a company statement attributed to co‑founder and CEO Peter Luo said.

Adagene centers its pipeline on the Dynamic Precision Library (DPL) discovery engine, which the company describes as an integrated suite of engineered antibody technologies including NEObody™, SAFEbody and POWERbody™. The firm positions SAFEbody as a precision masking approach that shields an antibody’s binding domain until activation in the tumor microenvironment, a design intended to reduce on‑target, off‑tumor toxicity and enable application across Fc‑empowered antibodies, antibody‑drug conjugates and bi/multi‑specific T‑cell engagers. The company says DPL enables translational studies in predictive preclinical models, a critical step for candidate selection ahead of clinical testing.

Adagene’s clinical portfolio includes multiple early‑stage programs that exemplify the platform strategy. ADG106 is a first‑in‑class anti‑CD137 monoclonal IgG4 now in Phase I testing for advanced solid and liquid tumors, with preliminary reporting of a favorable safety profile and biomarker evidence of T‑cell proliferation. ADG116, a fully human cross‑reactive antagonistic anti‑CTLA‑4 IgG1 with a dynamic soft‑ligand blocking mechanism and regulatory T cell depletion features, reportedly secured U.S. Food and Drug Administration IND clearance. ADG126 (muzastotug), a masked anti‑CTLA‑4 SAFEbody targeting tumor Tregs, is in Phase 1b/2 studies in combination with anti‑PD‑1 therapy with a development focus on metastatic microsatellite‑stable colorectal cancer; Adagene has cited that SAFEbody clinical data underpin an expanded collaboration with Sanofi.

The financing announcement sits atop a complex historical funding trail. Public material referenced multiple rounds: a reportedly identical $28 million Series B datelined Jan. 28, 2016 that named GP Healthcare Capital as lead investor; a March 2018 Series C of $50 million led by Sequoia China; and a later Series D that raised Adagene’s cumulative private financing to about $150 million with General Atlantic leading a $50 million investment. Sources do not reconcile the differing dates and investor lists attached to the $28 million Series B disclosures. Separately, Nasdaq‑cited materials note that proceeds from a Sanofi investment, together with audited cash and cash equivalents of $85.2 million as of Dec. 31, 2024, were expected to fund planned operations into 2027.

For investors and industry observers, the financing and program progress underscore two broader trends: sustained capital flows into engineered antibody platforms and increasing big‑pharma partnerships to de‑risk complex modalities. Masking technologies such as SAFEbody aim to expand the addressable market by improving therapeutic windows for potent modalities, which could reshape competition among ADCs, bispecifics and immune modulators. Regulatory engagement—evidenced by the ADG116 IND—and advancing clinical data will be pivotal to valuation and partner interest; biotech investors remain attentive to binary clinical readouts and the timeline for larger trials.

Policy and oversight considerations will grow as engineered biologics move into broader human testing, particularly for modalities that alter immune activity. Adagene’s new capital bolsters its runway to pursue those data milestones, but translating platform promise into regulatory‑proof clinical benefit will determine its commercial and market impact over the next two to three years.