X4 Pharma Raises $65.0 Million in Public Offering to Advance Lead Candidate Targeting WHIM Syndrome

One week after reporting positive top-line results from a pivotal trial of its lead investigational therapy mavorixafor in people with WHIM syndrome, X4 Pharmaceuticals raised $65 million to advance the experimental, oral, once-daily therapy towards a regulatory submission for approval.

Photo: X4 president and CEO Paula Ragan

WHIM (warts, hypogammaglobulinemia, infections, and myelokathexis) syndrome is a rare, inherited, combined immunodeficiency disease caused by reduced mobilization and trafficking of white blood cells from the bone marrow due to over-signaling of the CXCR4/CXCL12 pathway. People with WHIM syndrome characteristically have very low blood levels of neutrophils (neutropenia) and lymphocytes (lymphopenia), and as a result, experience frequent, recurrent infections with a high risk of lung disease, refractory warts from underlying human papillomavirus (HPV) infection, limited antibody production due to low levels of immunoglobulin, and an increased risk of developing certain types of cancer. Mavorixafor is an investigational small-molecule antagonist of CXCR4 being developed as a once-daily oral therapy to correct the dysfunction resulting from the underlying genetic causes of WHIM.

The pivotal 4WHIM phase 3 clinical trial of mavorixafor met its primary and secondary endpoints and was generally well tolerated in the trial, with no treatment-related serious adverse events reported and no discontinuations for safety events.

The company priced an underwritten public offering of 52.3 million shares of its common stock and, in lieu of common stock, pre-funded warrants to purchase 6.8 million shares of its common stock, and accompanying Class C warrants to purchase 29.55 million shares of its common stock at an exercise price of $1.50 per share of common stock (or, for investors who so choose, pre-funded warrants to purchase shares of its common stock) at a price to the public of $1.10 per share and accompanying Class C warrant (or $1.099 per pre-funded warrant and accompanying Class C warrant).

X4 has also granted the underwriters a 30-day option to purchase up to an additional 8.9 million shares of its common stock and/or Class C warrants to purchase up to an additional 4.4 million shares of its common stock at the public offering price, less underwriting discounts and commissions. X4’s gross proceeds from this offering are expected to be approximately $65.0 million (or approximately $74.8 million if the underwriters exercise their option in full), before deducting underwriting discounts and estimated offering expenses and any proceeds from the exercise of the warrants to be issued in the offering.

Author: Rare Daily Staff