Abcuro Raises $155 Million to Further Advance Autoimmune Pipeline

Rare Daily Staff

Abcuro, a clinical-stage company developing therapies to treat autoimmune diseases and cancer through precise modulation of cytotoxic T and NK cells, said it closed an oversubscribed $155 million series B financing.

Redmile Group and Bain Capital Life Sciences led the round, which included investment from new and existing investors including RA Capital Management, Samsara BioCapital, Sanofi Ventures, New Leaf Ventures, Pontifax, funds managed by Tekla Capital Management, funds and accounts managed by BlackRock, Mass General Brigham Ventures, Eurofarma, and Soleus Capital.

Abcuro will use the proceeds from the financing to complete a phase 2/3 registrational clinical trial evaluating ABC008, a first-in-class monoclonal antibody targeting killer cell lectin like receptor G1 (KLRG1), for the treatment of inclusion body myositis. The company will also focus on completing a phase 1/2 clinical trial of ABC008 in T cell large granular lymphocytic leukemia (T-LGLL), as well as initiating a phase 1/2 clinical trial in T and NK cell lymphomas.

Inclusion body myositis (IBM) is a rare condition that causes muscle weakness and damage. Symptoms of IBM vary, but usually include progressive weakness in muscles of the hand, forearm, thigh, and lower leg. Diagnosing IBM can be challenging because the symptoms, which normally appear as an adult or older adult, are not unique to this condition. Approximately 5,000 people have IBM in the United States.

“IBM, like other autoimmune diseases, is progressive and devastating for patients. Targeting the depletion of cytotoxic T cells that express KLRG1 with ABC008 is a novel approach that has generated exciting early data in patients with IBM,” said H. Jeffrey Wilkins, chief medical officer of Abcuro. “These data are also supportive of using ABC008 in other diseases like T-LGLL in which cytotoxic T cells are pathogenic, and mature T and NK cell lymphomas in which KLRG1 expressing cells are malignant. We look forward to further advancing these programs in the clinic.”

Killer cell lectin like receptor G1 (KLRG1) is an immune checkpoint cell surface receptor selectively expressed on late-differentiated effector memory and effector T cells. In autoimmune disease, highly cytotoxic T cells that drive disease progression express KLRG1. Conversely, in cancer, tumor cells expressing ligands that bind to the KLRG1 receptor inhibit effector T cells and natural killer (NK) cells and downregulate anti-tumor immunity. Abcuro says KLRG1 is, therefore, a compelling target in immune modulation in both autoimmune diseases and cancer as it enables the precise targeting of clinically relevant cytotoxic T and NK cells, while sparing naïve, central memory and regulatory T cells which are required to maintain normal immune system homeostasis.

ABC008 is a first-in-class anti-KLRG1 antibody capable of selectively depleting highly cytotoxic T cells, while sparing naïve, regulatory and central memory T cells. ABC008 has been designed to treat diseases mediated by highly cytotoxic T cells, including the autoimmune muscle disease IBM, T cell large granular lymphocytic leukemia, and mature T cell malignancies. The US Food and Drug Administration and the European Medicines Agency have granted Orphan Designation to ABC008 for the treatment of IBM.

Photo: H. Jeffrey Wilkins, chief medical officer of Abcuro