Third Rock Ventures' newest startup, Jounce Therapeutics Inc., plans to use its $47 million series A round to take on multiple protein-based methods of cancer immunotherapy.

The newco will focus initially on three approaches: inhibitors of immune checkpoints, like Yervoy ipilimumab from Bristol-Myers Squibb Co. (NYSE:BMY), and regulators of immune system co-stimulatory molecules and the tumor microenvironment.