Immunotherapies called checkpoint inhibitors have helped change the way a number of cancers are treated by blocking a tumor cell’s ability to hide from the immune system.
Some patients don’t respond, however, or develop resistance to these drugs. Iteos Therapeutics has raised $125 million to advance new cancer treatments it is developing to target two mechanisms it believes aid in the suppression of an anti-tumor immune response in the area immediately surrounding a tumor, or the tumor microenvironment.
The company’s lead program, EOS-850, is designed to target a receptor in the adenosine pathway. The investigational drug is in early-stage testing by itself, in combination with a Merck’s pembrolizumab (Keytruda), and in combination with chemotherapy in several types of solid tumors. The company’s other clinical-stage program, EOS-448, is designed to target regulatory T cells, or Tregs, which are abundant in some tumor tissues. That program entered the clinic in February 2020.
Other biotechs also view treating disease by controlling Tregs as a promising drug development area, including in indications beyond cancer. In 2018 Sangamo Biosciences, best known for its gene editing technology, acquired French biotech TxCell for its experimental technology that modifies Tregs to treat autoimmune diseases. Sonoma Bio raised $40 million and Pandion landed $80 million this year to advance Treg treatments to address similar disorders.
Iteos, a Belgium-based firm with US headquarters in Cambridge, MA, said the new money it has raised will also support preclinical research into potential therapies designed to address the same resistance mechanisms as its clinical-stage drug candidates.
The company’s financing—its second Series B close, following a $75 million tranche in 2018—was led by new investors RA Capital Management and Boxer Capital. Other investors in the round include new backers Janus Henderson, RTW Investments, and the Invus Group, and earlier investors MPM Capital, HBM Partners, Fund +, VIVES II, SRIW, and SFPI.