X4 Pharmaceuticals Closes $115 Million Loan Facility to Advance Pipeline

Rare Daily Staff

Rare disease drug developer X4 Pharmaceuticals closed a $115 million loan facility with Hercules Capital, drawing down $22.5 million at the transaction’s closing.

“This expanded loan facility creates significant financial flexibility for X4 as we continue preparations for the potential commercial launch of mavorixafor in individuals with WHIM syndrome and continue to advance mavorixafor for certain chronic neutropenic disorders,” said Adam Mostafa, chief financial officer of X4 Pharmaceuticals.

The company said the initial draw down strengthens its balance sheet on a non-dilutive basis and extends its projected cash runway into 2025, and creates expanded, future optionality beyond the equity capital markets as it potentially commerce product sales and monetize a priority review voucher next year.”

X4’s lead clinical candidate mavorixafor is a small molecule antagonist of chemokine receptor CXCR4 that is being developed as an oral, once-daily therapy. Due to its ability to increase the mobilization of mature, functional white blood cells from the bone marrow into the bloodstream, X4 believes that mavorixafor has the potential to provide therapeutic benefit across a variety of chronic neutropenic disorders, including WHIM (warts, hypogammaglobulinemia, infections, and myelokathexis) syndrome, a rare, primary immunodeficiency. Following announcement of positive data from the company’s global, pivotal, 4WHIM phase 3 clinical trial in May, it is currently preparing a U.S. regulatory submission seeking approval of oral, once-daily mavorixafor in the treatment of people aged 12 years and older with WHIM syndrome.

X4 is also currently evaluating mavorixafor in a phase 2 clinical trial in people with certain chronic neutropenic disorders following positive results from a phase 1b clinical trial of mavorixafor in people with congenital, idiopathic, or cyclic neutropenia.

The term loan facility provides for up to $115 million of term loans in the aggregate, available to be funded in multiple tranches. In addition to its initial drawdown, X4 may, for a period of time following U.S. approval of mavorixafor in individuals with WHIM syndrome, draw an additional tranche of up to $20 million.

An additional tranche will be available to X4 in the amount of up to $7.5 million for a period of time following achievement of a certain clinical development-related milestone. The availability of a final tranche of up to $32.5 million in support of X4’s growth initiatives is subject to the approval of the lenders. In addition, the availability of each tranche is subject to certain customary conditions for drawing. The facility refinances $32.5 million in outstanding principal indebtedness and extends the initial interest-only period and maturity of existing and future borrowings. X4 is under no obligation to draw funds in the future.

Photo: Adam Mostafa, chief financial officer of X4 Pharmaceuticals