Sunstone Life Science Fund III portfolio company, Rigontec GmbH and MSD today announced that MSD will acquire all outstanding shares in Rigontec. Under the terms of the agreement, MSD will make an upfront cash payment of EUR 115 million to Rigontec’s shareholders; based on the attainment of certain clinical, development, regulatory and commercial milestones, MSD may make additional contingent payments of up to EUR 349 million.

Rigontec is a pioneer in accessing the retinoic acid-inducible gene I (RIG-I) pathway, part of the innate immune system, as a novel and distinct approach in cancer immunotherapy to induce both immediate and long-term anti-tumor immunity. Rigontec’s lead candidate, RGT100, is currently in Phase I development evaluating treatment in patients with various tumors.

Rigontec was founded in 2014 as a spin-out of the University Bonn, Germany, and has to date raised close to EUR 30 million.