Thinly traded micro cap X4 Pharmaceuticals (XFOR +2.5%) is up, albeit on miniscule volume of 2,600 shares, in reaction to Breakthrough Therapy status for lead candidate mavorixafor for a rare inherited immunodeficiency disorder called WHIM syndrome, an Orphan Drug indication in both the U.S. and Europe.
A Phase 3 study is next up.
Breakthrough Therapy status provides for more intensive guidance from the FDA on development, the involvement of more senior agency personnel and a rolling review of the marketing application.
Mavorixafor is a small molecule antagonist of a protein called chemokine receptor type 4 (CXCR4). WHIM syndrome is caused by a mutation in the single gene that encodes the protein.
