ALX Oncology is a clinical-stage immuno-oncology company developing therapies that block the CD47 checkpoint mechanism, which is exploited by cancer cells to evade the immune system. Their lead candidate, ALX148, a next generation CD47 myeloid checkpoint inhibitor, is a fusion protein comprised of an engineered high affinity CD47 binding domain of SIRPα linked to an inactive Fc region of human immunoglobulin. ALX148 is designed to maximize the clinical benefit of anti-cancer therapeutics and is in clinical development for a broad range of tumor types.

CD47 inhibition is proving to be a promising new mechanism for the treatment of numerous oncology indications. With the unique ALX strategy of developing an agent with an inactive Fc region, Foresite Capital believes this product has the potential to be a highly differentiated and potentially best in class therapeutic for this class of anti-cancer drugs.