Atara Bio’s programs include T-cell product candidates and molecularly-targeted product candidates. T-cell product candidates include Epstein-Barr virus (EBV)-targeted cytotoxic T lymphocytes (CTLs), cytomegalovirus (CMV)-targeted CTLs, and Wilms Tumor 1 (WT1)-targeted CTLs. These T-cell product candidates are designed to target cancer cells or cells infected with certain viruses and kill them. The molecularly-targeted product candidates include STM 434 targeting activin and myostatin, members of the TGF-beta family of proteins that play roles in the control of muscle and other body tissues that hold potential for a number of clinical indications. Each product candidate is designed to address the underlying mechanisms of disease to treat conditions which have few therapeutic options today.