Muscle-loss biotech Atara Biotherapeutics files for a $50 million IPO

Atara Biotherapeutics, an early-stage biotech targeting muscle loss in patients with end-stage renal disease, filed on Friday with the SEC to raise up to $50 million in an initial public offering. The company lists Celgene (CELG)and Amgen (AMGN) among its primary shareholders. The Brisbane, CA-based company, which was founded in 2012, plans to list on the NASDAQ under the symbol ATRA. Atara Biotherapeutics initially filed confidentially on April 10, 2014. Goldman Sachs and Citi are the joint bookrunners on the deal. No pricing terms were disclosed.