XFOR

X4 Pharmaceuticals, Inc.

A Boston-based biopharmaceutical company that makes medicines for rare immune-system diseases. Its drug XOLREMDI (mavorixafor), an oral pill approved by the FDA, treats WHIM syndrome, an ultra-rare inherited disorder that traps infection-fighting white blood cells in the bone marrow. Founded around 2015, the company took its name from the CXCR4 receptor its drug targets, and it built its lead medicine from a molecule originally developed by Sanofi.