Last week, Pfizer announced that it will acquire Trillium Therapeutics, a clinical stage immune-oncology company based in Cambridge, Massachusetts. Under the agreement, Pfizer reported that it “will acquire all outstanding shares of Trillium not already owned by Pfizer for an implied equity value of $2.26 billion, or $18.50 per share, in cash,” and its two lead molecules.  These molecules, TTI-622 and TTI-621, are SIRPα-Fc fusion proteins being developed across several indications, with a focus on hematological malignancies. Hematological malignancies are cancers that affect the blood, bone marrow, and lymph nodes, including various types of leukemia, multiple myeloma, and lymphoma.