Abcuro secures $200M Series C for KLRG1 antibody trial

Abcuro, a biotechnology company backed by Sanofi, has recently secured $200 million in Series C funding aimed at advancing its anti-KLRG1 antibody, ulviprubart, through a critical phase 2/3 clinical trial. The company is focusing on the treatment of muscle diseases, specifically targeting the depletion of cytotoxic T cells in autoimmune conditions. Unlike others in the field who are focusing on targets such as CD25, CD2, CD52, and ICOS, Abcuro has chosen to target KLRG1. This molecule is primarily expressed in highly cytotoxic late-differentiated effector memory and effector T cells. By targeting KLRG1, the company aims to eliminate cells that drive autoimmune diseases while sparing regulatory and central memory T cells.

Ulviprubart, also known as ABC008, is currently being evaluated in a phase 2/3 trial for inclusion body myositis (IBM), a debilitating muscle-wasting disease that impacts approximately 50,000 individuals across the United States and Europe. The outcome of this study is crucial for Abcuro, as a successful trial could lead to an application for approval to the FDA, anticipated in the first half of 2026. In preparation for a potential commercial launch, a portion of the Series C funds is being allocated to prepare for manufacturing and commercialization efforts.

The Series C financing round was spearheaded by New Enterprise Associates, with new participation from Foresite Capital. The round also saw contributions from existing investors such as Sanofi Ventures, RA Capital, Bain Capital Life Sciences, Redmile Group, Samsara BioCapital, Pontifax, Mass General Brigham Ventures, New Leaf Ventures, and funds managed by BlackRock. Alex Martin, CEO of Abcuro, expressed in a recent statement that the continued support from investors underscores the potential of ulviprubart as an innovative treatment for severe diseases driven by highly cytotoxic T cells, including IBM.

IBM serves as an ideal testing ground for the drug due to the T-cell attacks on muscle fibers characteristic of the disease, which result in significant loss of hand function and mobility. In 2019, Abcuro's founder and neurologist at Brigham and Women’s Hospital, Steven Greenberg, M.D., co-authored a study linking KLRG1-expressing T cells to IBM, which prompted Mass General Brigham Ventures and Sanofi Ventures to initiate a Series A-1 funding round in 2021 to further develop this research. This was followed by a successful Series B round that raised $155 million in 2023.

In addition to the ongoing phase 2/3 study in IBM, Abcuro is also conducting a phase 1/2 clinical trial of ulviprubart in T-cell large granular lymphocytic leukemia. This diversification illustrates the company’s broader strategy to explore the therapeutic potential of ulviprubart in various T-cell-mediated disorders. As Abcuro advances ulviprubart through these trials, the biotech industry and patients alike are keenly watching the developments and results that could herald a new therapeutic option for challenging autoimmune diseases.