X4 Pharmaceuticals, Inc

Previous wording

The FDA has granted Fast Track designation to mavorixafor for the treatment of CN, which is defined as periods lasting more than three months persistently or intermittently where there are abnormally low levels of neutrophils circulating in the blood, and may be idiopathic (of unknown origin), cyclic (episodes typically occurring every three weeks), or congenital (of genetic causation). CN disorders are rare blood conditions similarly characterized by increased risks of infections and cancer due to abnormally low levels of neutrophils in the body. In all cases, the CXCL12/CXCR4 pathway is the key regulator of neutrophil release from the bone marrow.

Current wording

We are a biopharmaceutical company developing and commercializing novel therapeutics for the treatment of rare hematology diseases. We continue to progress our global, pivotal Phase 3 clinical trial (the “4WARD” trial) to evaluate the efficacy, safety, and tolerability of oral, once-daily mavorixafor, with or without stable doses of granulocyte colony-stimulating factor (“G-CSF”) in people with primary chronic neutropenia (congenital, acquired autoimmune, or idiopathic) (“PCN”) who are experiencing recurrent and/or serious infections. Mavorixafor has been granted Fast Track designation for the treatment of PCN, which is defined as periods lasting more than three months persistently or intermittently where there are abnormally low levels of neutrophils circulating in the blood, and may be idiopathic (of unknown origin), cyclic (episodes typically occurring every three weeks), or congenital (of genetic causation). PCN disorders are rare blood conditions similarly characterized by increased risks of infections and cancer due to abnormally low levels of neutrophils in the body. In all cases, the CXCL12/CXCR4 pathway is the key regulator of neutrophil release from the bone marrow.

Previous wording

We have one commercially approved product, XOLREMDI® (mavorixafor), which has received accelerated approval in the United States from the FDA for use as an oral, once-daily therapy in patients 12 years of age and older with WHIM (warts, hypogammaglobulinemia, infections, and myelokathexis) syndrome, to increase the number of circulating mature neutrophils and lymphocytes. WHIM syndrome is a rare combined primary immunodeficiency and CN disorder. We are committed to making XOLREMDI available to patients in need in the U.S. while maintaining our focus on our long-term strategy to successfully complete the 4WARD trial in patients with moderate and severe CN.

Current wording

We currently have one commercially approved product, XOLREMDI® (mavorixafor), which has received accelerated approval in the United States from the FDA for use as an oral, once-daily therapy in patients 12 years of age and older with WHIM (warts, hypogammaglobulinemia, infections, and myelokathexis) syndrome, to increase the number of circulating mature neutrophils and lymphocytes. WHIM syndrome is a rare combined primary immunodeficiency and PCN disorder. We are committed to making XOLREMDI available to patients in need in the U.S. while maintaining our focus on our long-term strategy to successfully complete the 4WARD trial in patients with moderate and severe PCN.

Previous wording

The following table summarizes the results of our operations for the three and six months ended June 30, 2026 and 2025:

Current wording

The following table summarizes the results of our operations for the three and nine months ended September 30, 2026 and 2025:

Previous wording

Net product sales were $2.4 million and $1.7 million for the three months ended June 30, 2026 and 2025, respectively, and were $4.8 million and $2.7 million for the six months ended June 30, 2026 and 2025, respectively. Net product revenue growth over the prior year periods was primarily due to an increase in the number of patients who have been prescribed the Company’s drug product. Gross-to-net adjustments were approximately 10% in the first half of 2026. Co-pay assistance payments and rebates to U.S. government payors have comprised the majority of our gross-to-net revenue adjustments.

Current wording

Net product sales were $2.8 million and $1.6 million for the three months ended September 30, 2026 and 2025, respectively, and were $7.6 million and $4.3 million for the nine months ended September 30, 2026 and 2025, respectively. Net product revenue growth over the prior year periods was primarily due to an increase in the number of patients who have been prescribed our drug product. Gross-to-net adjustments were approximately 9% of gross revenues in the three and nine months ended September 30, 2026. Co-pay assistance payments and rebates to U.S. government payors have comprised the majority of our gross-to-net revenue adjustments.

Previous wording

During the three and six months ended June 30, 2026, license and other revenue under the Norgine Agreement was primarily comprised of $5.5 million of license revenue associated with the achievement of a regulatory milestone and $1.0 million and $1.2 million, respectively, of sales of drug supply to Norgine for early-access programs and future commercial sales. License and other revenue was not significant in the three months ended June 30, 2025. For the six months ended June 30, 2025, license and other revenue was primarily comprised of $27.6 million in license revenue in connection with the delivery of a license upon the execution of the Norgine Agreement and$0.5 million for the provision of research and development services thereunder.

Current wording

During the three months ended September 30, 2026 and September 30, 2025, license and other revenue was primarily comprised of $0.1 million and $0.2 million, respectively, for provision of research and development services under the Norgine Agreement. During the nine months ended September 30, 2026, license and other revenue was comprised of $5.5 million of license revenue associated with the achievement of a regulatory milestone, $0.1 million for the provision of research and development services and $1.2 million for the sale of drug supply to Norgine to support their early-access programs and commercial sales. For the nine months ended September 30, 2025, license and other revenue was primarily comprised of $27.6 million in license revenue in connection with the delivery of a license upon the execution of the Norgine Agreement and$0.7 million for the provision of research and development services thereunder.

Previous wording

Cost of revenue primarily consists of amortization of an intangible asset related to milestone payments associated with our Genzyme license agreement, cost of manufactured drug product sold, and sales-based or sublicense-based royalty payments due under our Genzyme license agreement. Cost of revenue increased $1.3 million in the three months ended June 30, 2026 as compared to the same period in the prior year due to an increase in net product sales and an increase in drug supply sales. Cost of revenue decreased $2.8 million in thesix months ended June 30, 2026, as compared to the same period in the prior year, primarily due to prior year royalties due under our Genzyme license agreement associated with sublicense income from the Norgine Agreement that did not reoccur in the current period, partially offset by higher intangible amortization in the current period.

Current wording

Cost of revenue primarily consists of amortization of an intangible asset related to milestone payments associated with our Genzyme license agreement, cost of manufactured drug product sold, and sales-based or sublicense-based royalty payments due under our Genzyme license agreement. Cost of revenue increased $0.1 million in the three months ended September 30, 2026 as compared to the same period in the prior year due to an increase in net product sales and an increase in drug supply sales. Cost of revenue decreased $2.7 million in thenine months ended September 30, 2026, as compared to the same period in the prior year, primarily due to prior year royalties due under our Genzyme license agreement associated with sublicense income from the Norgine Agreement that did not recur in the current period, partially offset by higher intangible amortization and a higher volume of drug product sold in the current period.

Previous wording

Substantially all of our research and development has been focused on our one product candidate, mavorixafor (X4P-001), specifically for the CN indication in the U.S. The following table shows external costs incurred by product candidate (primarily external CRO costs) and unallocated research and development costs, primarily consisting of employee salaries and related expense for our research and development organization.

Current wording

Substantially all of our research and development has been focused on our one product candidate, mavorixafor (X4P-001), specifically for the PCN indication in the U.S. The following table shows external costs incurred by product candidate (primarily external CRO costs) and unallocated research and development costs, primarily consisting of employee salaries and related expense for our research and development organization.

Previous wording

Research and development expenses decreased by $3.3 million and $6.4 million in the three and six months ended June 30, 2026, respectively, as compared to the same periods in the prior year. The decrease was primarily due to lower compensation and related benefit costs as a result of strategic restructuring actions implemented in the prior year, partially offset by higher clinical costs, primarily CRO costs related to our 4WARD trial.

Current wording

Research and development expenses decreased by $4.0 million and $10.3 million in the three and nine months ended September 30, 2026, respectively, as compared to the same periods in the prior year. The decrease was primarily due to lower compensation and related benefit costs as a result of strategic restructuring actions implemented in the prior year. During the nine months ended September 30, 2026, research and development expenses allocated to mavorixafor, primarily CRO costs, increased to$29.6 million as compared to $28.2 million in the prior year as we continue to advance our 4WARD trial. The increase in the current nine month period was offset by lower unallocated expenses in the current period, primarily due tolower compensation and related benefit costs as a result of lower head count in the research and development organizations relative to the prior year.

Previous wording

General and administrative expenses decreased by $1.0 million and $9.1 million for thethree and six months ended June 30, 2026, respectively, as compared to the same period in the prior year. The decrease for the three month period was primarily due to a reduction in legal, IT and sales and marketing costs, partially offset by higher stock-based compensation expense. The decrease for the six month period was primarily due to a significant reduction in sales and marketing expenses related to our approved drug product, a reduction in outside legal expenses, and reductions in compensation costs due to lower head count in general and administrative functions.

Current wording

General and administrative expenses decreased by $2.5 million and $11.6 million for thethree and nine months ended September 30, 2026, respectively, as compared to the same periods in the prior year. The decrease for the three month period was primarily due to a reduction in legal and IT costs, partially offset by higher stock-based compensation expense and sales and marketing costs, primarily related to PCN market assessment and preparation activities. The decrease for the nine month period was primarily due to a significant reduction in sales and marketing expenses related to our approved drug product, a reduction in outside legal expenses, and reductions in compensation costs due to lower headcount in general and administrative functions.

Previous wording

Other income, net, decreased approximately $0.3 million and $10.0 million in the three and six months ended June 30, 2026, respectively, as compared to the same period in the prior year primarily due to lower gains in the current period on fair value adjustments related to our Class C warrants, partially offset by higher interest income on ourmarketable security investment portfolio.

Current wording

Other expense, net, decreased approximately $2.1 million in the three months ended September 30, 2026 compared to the same period in the prior year primarily due to the higher interest income on our marketable security investment portfolio and higher gains in the current period on fair value adjustments related to our Class C warrants. Other income, net, decreased approximately $7.9 million in the nine months ended September 30, 2026 compared to the same period in the prior year primarily due to lower gains in the current period on fair value adjustments related to our Class C warrants, partially offset by higher interest income on ourmarketable security investment portfolio.

Previous wording

To date, we have funded our operations primarily with proceeds from sales of common stock, warrants and prefunded warrants for the purchase of our preferred stock and our common stock, sales of preferred stock, proceeds from the issuance of convertible debt and borrowings under loan and security agreements.

Current wording

To date, we have funded our operations primarily with proceeds from sales of common stock, warrants and pre-funded warrants for the purchase of our preferred stock and our common stock, sales of preferred stock, proceeds from the issuance of convertible debt and borrowings under loan and security agreements.

Previous wording

2025 we completed an underwritten public offering of approximately 52.8 million shares of our common stock and prefunded warrants to purchase up to 700,000 shares of our common stock for net proceeds of $145.6 million, after underwriting discounts and offering expenses.

Current wording

Public and Private Equity Offerings. Over the past several years, we have funded our operations from sales of common stock, warrants and pre-funded warrants through both public offerings and private placements. For example, most recently in October 2025, we completed an underwritten public offering of approximately 52.8 million shares of our common stock and pre-funded warrants to purchase up to 700,000 shares of our common stock for net proceeds of $145.6 million, after underwriting discounts and offering expenses (the “October 2025 Offering”).

Previous wording

Hercules Loan Agreement. We are a party to a loan and security agreement (the “Hercules Loan Agreement”), which provides for a term loan facility of up to $107.5 million, under which we have borrowed an aggregate of $75.0 million of term loans to date, representing the maximum borrowings as of June 30, 2026. The term loan facility requires that we make interest-only payments through maturity on July 1, 2027 and requires that we meet certain operational and financial covenants. See Note 11 to our Annual Report on Form 10-K as filed with the SEC on March 17, 2026 for a full description of our Hercules Loan Agreement.

Current wording

Hercules Loan Agreement. We were a party to a loan and security agreement (the “Hercules Loan Agreement”), which provided for a term loan facility of up to $107.5 million, under which we had borrowed an aggregate of $75.0 million of term loans to date, representing the maximum borrowings as of September 30, 2026. See Note 11 to our Annual Report on Form 10-K as filed with the SEC on March 17, 2026 for a full description of our Hercules Loan Agreement. In October 2026, we refinanced and retired the Hercules Loan Agreement by entering into a new loan agreement (the “K2 Loan Agreement”), which provides up to $150.0 million of term loan capacity and matures in October 2030. The K2 Loan Agreement requires interest-only payments through October 1, 2029, and principal and interest payments thereafter for 13 months. The interest-only period is extended if we meet certain operational milestones. See Note 16 to the condensed consolidated financial statements included in this Quarterly Report on Form 10-Q for more information on the K2 Loan Agreement.

Previous wording

During the six months ended June 30, 2026, net cash used in operating activities was $40.4 million, primarily resulting from our net losses of $36.4 million adjusted for non-cash items of $7.2 million, primarily consisting of stock-based compensation, and changes in operating assets and liabilities of $11.2 million, primarily due to increases is in accounts receivable due to increases in revenue, and decreases in accounts payable and accrued expenses due to timing of vendor payments. During the six months ended June 30, 2025, net cash used in operating activities was $42.3 million, primarily resulting from net losses of $25.5 million adjusted for net non-cash income (expense) of $9.3 million, which includes a $13.5 million gain for the adjustment of our Class C warrant liability to fair value. Net cash used in operating activities also includes $7.5 million of changes to operating assets and liabilities primarily related to a reduction in accrued expenses.

Current wording

During the nine months ended September 30, 2026, net cash used in operating activities was $60.6 million, primarily resulting from our net losses of $56.6 million adjusted for non-cash items of $11.4 million, primarily consisting of stock-based compensation, and changes in operating assets and liabilities of $15.4 million, primarily due to increases in accounts receivable due to increases in revenue, and decreases in accounts payable and accrued expenses due to timing of vendor payments. During the nine months ended September 30, 2025, net cash used in operating activities was $70.1 million, primarily resulting from net losses of $55.3 million adjusted for net non-cash income of $6.7 million, which includes a $12.8 million gain for the adjustment of our Class C warrant liability to fair value. Net cash used in operating activities also includes $8.1 million of changes to operating assets and liabilities primarily related to a reduction in accounts payable and accrued expenses.

Previous wording

During the six months ended June 30, 2026 and 2025, cash provided by investing activities of $18.3 million and $20.0 million, respectively, was primarily due to net maturities and sales of short-term marketable securities.

Current wording

During the nine months ended September 30, 2026, cash provided by investing activities of $29.3 million was primarily due to net maturities and sales of short-term marketable securities. During the nine months ended September 30, 2025, cash used in investing activities of $8.7 million primarily included net purchase of short-term marketable securities.

Previous wording

There were no significant cash flows from financing activities during the six months ended June 30, 2026. During the six months ended June 30, 2025, cash provided by financing activities of $5.6 million was primarily due to sales of

Current wording

During the nine months ended September 30, 2026, cash flows from financing activities were not significant. During the nine months ended September 30, 2025, cash provided by financing activities of $92.5 million was primarily due to sales of our common stock and pre-funded warrants in our August 2025 private placement, sales of our common stock through our ATM program and a common stock purchase agreement.

Previous wording

During the three months ended June 30, 2026, there were no material changes to our critical accounting policies as reported for the year ended December 31, 2025 as part of our Annual Report on Form 10-K. See Note 1 to the unaudited interim condensed consolidated financial statements included in this Quarterly Report on Form 10-Q under the heading Recently Issued Accounting Standards Not Yet Adopted for new accounting pronouncements or changes to the accounting pronouncements during the three months ended June 30, 2026.

Current wording

During the nine months ended September 30, 2026, there were no material changes to our critical accounting policies as reported for the year ended December 31, 2025 as part of our Annual Report on Form 10-K. See Note 1 to the unaudited interim condensed consolidated financial statements included in this Quarterly Report on Form 10-Q under the heading Recently Issued Accounting Standards Not Yet Adopted for new accounting pronouncements or changes to the accounting pronouncements during the nine months ended September 30, 2026.