The acquisition will expand Horizon's pipeline and accelerate the company's long-term growth. With the acquisition, Horizon will gain rights to Viela's product development pipeline, which includes four therapeutic candidates currently in nine development programs. These include:

• Uplizna, a U.S. Food and Drug Administration-approved B-cell depleting humanized monoclonal antibody for the treatment of neuromyelitis optica spectrum disorder (NMOSD), a rare, severe autoimmune disease that attacks the optic nerve, spinal cord, and brain stem. This product is in phase II and III trials for additional indications.
• VIB4920, an investigational fusion protein designed to block a key co-stimulatory pathway involved in many autoimmune and inflammatory diseases. This product is in phase II/IIB trials.
• VIB7734, an investigational human monoclonal antibody designed to deplete plasmacytoid dendritic cells (pDCs), a cell type believed to be critical to the pathogenesis of multiple autoimmune diseases. Phase II trials for systemic lupus erythematosus is expected to start in the first half of 2021, and it is currently undergoing a phase I study for COVID-19.
• VIB1116, a monoclonal antibody for autoimmune diseases expected to begin a phase I first-in-human trial in mid-2021.

Horizon intends to finance the transaction through $1.3 billion of external debt along with cash on hand.