Preliminary Top-Line Data Expected by the End of the Fourth Quarter of 2015

SOUTH SAN FRANCISCO, CA, USA I August 31, 2015 I Atara Biotherapeutics, Inc. (ATRA), a biopharmaceutical company with a focus on developing innovative therapies for patients with debilitating diseases, today announced that it completed enrollment in its blinded, randomized, PINTA 745 Phase 2 clinical trial in End-Stage Renal Disease (ESRD) patients with Protein Energy Wasting (PEW). The company expects to report preliminary top-line data by the end of the fourth quarter of 2015.

PINTA 745 is a peptibody that binds myostatin and inhibits its corresponding signal transduction, thereby blocking the negative regulation of skeletal muscle growth. Atara Bio is conducting a Phase 2 trial in patients with ESRD who are also suffering from PEW at six US-based sites. PEW refers to a state of muscle wasting, inflammation and malnutrition that increases patients’ risk for infections, cardiovascular disease and other complications. The company believes that patients with PEW may benefit from the muscle-building demonstrated in earlier clinical trials and anti-inflammatory properties of PINTA 745 demonstrated in preclinical studies. The clinical trial was designed to provide proof of concept data for ESRD patients.

“Atara Bio is pleased to report the completion of enrollment to the PINTA 745 trial and looks forward to reviewing the data towards the end of this year,” said Christopher Haqq, MD, Chief Medical Officer of Atara Bio.

About Atara Biotherapeutics, Inc.

Atara Biotherapeutics, Inc. is a biopharmaceutical company focused on developing innovative therapies for patients with debilitating diseases. Atara Bio’s programs include molecularly targeted product candidates and T-cell product candidates. Molecularly targeted product candidates include PINTA 745, STM 434 and ATA 842, members of the TGF-beta family of proteins that target myostatin and activin, and have demonstrated the potential to have therapeutic benefit in a number of clinical indications. T-cell product candidates include EBV-CTL, CMV-CTL and WT1-CTL.

SOURCE: Atara Biotherapeutics