Merck KGaA, which operates its biopharmaceutical business in the U.S. and Canada as EMD Serono, has entered into a collaboration and licensing agreement with Domain Therapeutics of Strasbourg, France, to explore adenosine inhibition in the development of novel immuno-oncology agents.    Adenosine receptor antagonists are small molecules thought to slow tumor progression and improve the response to combination immunotherapies by inhibiting adenosine, a compound generated by cancer cells that in...