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FORM 10-K

(Mark One)

x			ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

o			ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

________________________________________________________________________________________________________

Delaware (State or other jurisdiction of incorporation or organization)			27-3181608 (I.R.S. Employer Identification No.)
61 North Beacon Street, 4th Floor Boston, Massachusetts (Address of principal executive offices)			02134 (Zip Code)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common Stock

XFOR

The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large Accelerated Filer

☐

Accelerated Filer

☐

Non-accelerated filer

☒

Smaller reporting company

☒

Emerging growth company

☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.   ☐

On June 30, 2022, the aggregate market value of the registrant’s voting common stock held by non-affiliates of the registrant was approximately $29.6 million based upon the closing sale price on the Nasdaq Capital Market reported on June 30, 2022.

Independent Registered Public Accounting Firm

PricewaterhouseCoopers LLP

Boston, Massachusetts, US

Firm ID

238

As of March 15, 2023, there were 122,207,488 shares of the registrant’s common stock, $0.001 par value per share outstanding.

TABLE OF CONTENTS

PART I
Item 1.			BUSINESS			5
Item 1A.			RISK FACTORS			24
Item 1B.			UNRESOLVED STAFF COMMENTS			62
Item 2.			PROPERTIES			62
Item 3.			LEGAL PROCEEDINGS			62
Item 4.			MINE SAFETY DISCLOSURES			62
PART II
Item 5.			MARKET FOR REGISTRANT'S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES			63
Item 6.			[RESERVED]			63
Item 7.			MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS			63
Item 7A.			QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK			73
Item 8.			FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA			73
Item 9.			CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURES			74
Item 9A.			CONTROLS AND PROCEDURES			74
Item 9B.			OTHER INFORMATION			75
Item 9C.			DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS			89
PART III
Item 10.			DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE			75
Item 11.			EXECUTIVE COMPENSATION			75
Item 12.			SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS			75
Item 13.			CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE			75
Item 14.			PRINCIPAL ACCOUNTANT FEES AND SERVICES			75
PART IV
Item 15.			EXHIBIT AND FINANCIAL STATEMENT SCHEDULES			76
Item 16.			FORM 10-K SUMMARY			79

•the potential benefits, including clinical utility, that may be derived from any of our product candidates;

•the timing of and our ability to obtain and maintain regulatory approval of our existing product candidates or any product candidates that we may develop in the future, and any related restrictions, limitations, or warnings in the label of any approved product candidates;

•our plans to research, develop, manufacture and commercialize our product candidates;

•the timing of our regulatory filings for our product candidates, along with regulatory developments in the United States and other foreign countries;

•the size and growth potential of the markets for our product candidates, if approved, and the rate and degree of market acceptance of our product candidates, including reimbursement that may be received from payors;

•the benefits of U.S. Food and Drug Administration and European Commission designations, including, without limitation, Fast Track, Orphan Drug and Breakthrough Therapy;

•our commercialization, marketing and manufacturing capabilities and strategy;

•our ability to attract and retain qualified employees and key personnel;

•our competitive position and the development of and projections relating to our competitors or our industry;

•our expectations regarding our ability to obtain and maintain intellectual property protection;

•the success of competing therapies that are or may become available;

•our estimates and expectations regarding future operations, financial position, revenues, costs, expenses, uses of cash, capital requirements or our need for additional financing;

•our ability to continue as a going concern;

•our plans to in-license, acquire, develop and commercialize additional product candidates;

•the impact of laws and regulations;

•our plans to identify additional product candidates with significant commercial potential that are consistent with our commercial objectives;

•our ability to raise additional capital;

•our strategies, prospects, plans, expectations or objectives; and

•other risks and uncertainties, including those listed under the section titled “Risk Factors” in this Annual Report.

WHIM syndrome is named for its four common clinical findings, although not all patients experience all symptoms, and not all symptoms are required for a diagnosis: Warts, related to infection with the Human Papilloma Virus (HPV), Hypogammaglobulinemia, a condition of low immunoglobulin (“IG”) levels, Infections, including both bacterial and fungal infections, and Myelokathexis, a hyper-dense population of immune cells in the bone marrow. These conditions reduce the body’s ability to achieve a healthy immune response. Approximately 30-40% of people with WHIM syndrome develop HPV-associated cancers as they age.

We currently have a master services agreement (“the Aptuit Agreement”) in place with Aptuit (Oxford) Ltd (“Aptuit”), pursuant to which Aptuit develops and manufactures the active pharmaceutical ingredient (“API”) for mavorixafor. The term of the Aptuit Agreement expires in February 2024 unless terminated by us and/or Aptuit. Aptuit is our sole supplier for mavorixafor drug substance and is currently manufacturing mavorixafor drug substance at a commercially relevant scale to support our ongoing and anticipated future supply needs.

We are obligated to use commercially reasonable efforts to develop and commercialize licensed products for use in the field in the United States and at least one other major market country. We have the right to grant sublicenses of the licensed rights that cover mavorixafor to third parties. If we wish to grant a sublicense to any licensed product other than mavorixafor, we are obligated to first offer the sublicense to Genzyme. If Genzyme expresses written interest for the sublicense, then we will negotiate exclusively with Genzyme for a certain stated period to obtain a license to such rights, after which Genzyme shall have no further rights with respect to such licensed product and we will be free to negotiate a sublicense with respect to such licensed product with any third party.

We are obligated to pay Genzyme milestone payments in the aggregate amount of up to $25 million, contingent upon our achievement of certain late-stage regulatory and sales milestones with respect to licensed products, and tiered royalties based on net sales of licensed products that we commercialize under the Genzyme agreement. Our obligation to pay royalties for each licensed product expires on a country-by-country basis on the latest of (i) the expiration of licensed patent rights that cover that licensed product in that country, (ii) the expiration of regulatory exclusivity in that country and (iii) ten years after the first commercial sale of such licensed product in that country. Royalty rates are subject to reduction under the agreement in specified circumstances, including in any country if we are required to obtain a license from any third party to the extent our patent rights might infringe the third party’s patent rights, if a licensed product is not covered by a valid claim in that country or if sales of generic products reach certain thresholds in that country. Sublicenses that we enter into under the Genzyme agreement, including our license agreement with Abbisko obligate us to pay Genzyme a percentage of certain upfront, maintenance fees, milestone payments and royalty payments paid to us by the sublicensee.

In November 2020, we entered into a license agreement with Dana Farber Cancer Institute (“DFCI”) pursuant to which we obtained a non-exclusive, worldwide license to use, make, have made, develop, market, import, distribute, sell and have sold licensed products and certain processes covered by licensed patent rights owned by DFCI. The rights licensed to us are for the therapeutic use of our CXCR4 antagonists for the treatment of Waldenström’s in combination with BTK inhibitors, including ibrutinib. We have the right to grant sublicenses of the licensed rights to third parties to the extent consistent with the terms of the DFCI agreement.

The term of the DFCI agreement will continue until the expiration of the last valid claim within the patent rights covering the licensed product. DFCI may terminate the DFCI agreement in the event (i) we fail to pay any amount and fail to cure such failure within 30 days after receipt of notice, (ii) we cease to carry on our business with respect to the licensed products or process, (iii) the insurance coverage that we are obligated to maintain under the DCFI agreement is terminated and we fail to obtain replacement insurance within a certain period of time following notice to DFCI, (iv) we fail to comply with certain diligence obligations and cure any such default within 60 days after receipt of written notice, (v) we have granted a sublicense without notifying DFCI or on terms inconsistent with the terms required of sublicenses under the DCFI agreement, (vi) an officer of our company, an affiliate or sublicensee is convicted of a felony relating to the manufacture, use, sale or importation of a licensed product, (vii) we or any of our affiliates, sublicensees or sublicensees’ affiliates initiate a patent challenge of the patents licensed under the DFCI agreement or assists others in doing so or (viii) we declare insolvency or bankruptcy. In addition, if we are in material breach of any material obligations under the DFCI agreement and fail to remedy such breach within 90 days after receipt of notice, DFCI may terminate the DFCI agreement or terminate any licenses granted under the agreement. We may terminate the DFCI agreement at any time upon at least 90 days’ written notice.

We file patent applications directed to our product candidates, preclinical compounds and related technologies to establish intellectual property positions on these compounds and their uses in disease. As of December 31, 2022, we owned or exclusively licensed 18 issued U.S. patents, 14 pending U.S. non-provisional patent applications, eight pending U.S. provisional patent application, and approximately 175 PCT and foreign patents and patent applications in the following foreign jurisdictions: Belgium, Brazil, Canada, China, European Patent Office, France, Germany, Great Britain, Hong Kong, India, Ireland, Italy, Israel, Japan, Lichtenstein, Mexico, Netherlands, New Zealand, Singapore, South Africa, Spain, Sweden and Switzerland.

As of December 31, 2022, our in-licensed intellectual property portfolio for mavorixafor included three issued U.S. patents and one pending U.S. patent application directed to mavorixafor, including one issued U.S. patent with claims directed to a crystalline salt form of mavorixafor, one issued U.S. patent directed to pharmaceutical compositions of mavorixafor in unit dosage form, and one issued U.S. patents directed to methods of making mavorixafor and key intermediates. These in-licensed patents are expected to expire between 2024 and 2027. We also had four issued U.S. patents directed to compositions and methods of making chemical compounds related to the X4P-001 program. Approximately 61 corresponding foreign patents directed to compositions of matter and related chemical compounds as well as methods of making and methods of use were issued or pending. All of the above patents and patent applications were exclusively licensed to us pursuant to the terms of the Genzyme agreement.

The Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act of 2010, collectively, the ACA, was enacted with the goal of expanding coverage for the uninsured while at the same time containing overall health care costs. With regard to pharmaceutical products, among other things, the ACA expanded and increased industry rebates for drugs covered under Medicaid programs and made changes to the coverage requirements under the Medicare D program. There have been challenges to certain aspects of the ACA. For example, on June 17, 2021, the U.S. Supreme Court dismissed a challenge on procedural grounds that argued the ACA is unconstitutional in its entirety because the “individual mandate” was repealed by Congress. Prior to the U.S. Supreme Court ruling, on January 28, 2021, President Biden issued an executive order to initiate a special enrollment for purposes of obtaining health insurance coverage through the ACA marketplace. The executive order also instructed certain governmental agencies to review and reconsider their existing policies and rules that limit access to healthcare, including among others, reexamining Medicaid demonstration projects and waiver programs that

Also, there has been heightened governmental scrutiny recently over pharmaceutical pricing practices in light of the rising cost of prescription drugs and biologics. Such scrutiny has resulted in several Presidential executive orders, Congressional hearings and proposed and enacted federal and state legislation designed to, among other things, bring more transparency to product pricing, review the relationship between pricing and manufacturer patient programs, and reform government program reimbursement methodologies for products. For example, in July 2021, the Biden administration released an executive order, “Promoting Competition in the American Economy,” with multiple provisions aimed at prescription drugs. In response to Biden’s executive order, on September 9, 2021, HHS released a Comprehensive Plan for Addressing High Drug Prices that outlines principles for drug pricing reform and sets out a variety of potential legislative policies that Congress could pursue as well as potential administrative actions HHS can take to advance these principles. In addition, the IRA, among other things, (i) directs HHS to negotiate the price of certain high-expenditure, single-source drugs and biologics covered under Medicare, and subject drug manufacturers to civil monetary penalties and a potential excise tax by offering a price that is not equal to or less than the negotiated “maximum fair price” for such drugs and biologics under the law, and (ii) imposes rebates with respect to certain drugs and biologics covered under Medicare Part B or Medicare Part D to penalize price increases that outpace inflation. The IRA permits HHS to implement many of these provisions through guidance, as opposed to regulation, for the initial years. These provisions will take effect progressively starting in fiscal year 2023, although they may be subject to legal challenges. It is currently unclear how the IRA will be implemented but is likely to have a significant impact on the pharmaceutical industry. Further, the Biden administration released an additional executive order on October 14, 2022, directing HHS to submit a report on how the Center for Medicare and Medicaid Innovation can be further leveraged to test new models for lowering drug costs for Medicare and Medicaid beneficiaries. It is unclear whether this executive order or similar policy initiatives will be implemented in the future. Further, Congress is considering additional health reform measures. At the state level, legislatures have increasingly passed legislation and implemented regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing.

We are a late clinical-stage biopharmaceutical company. Investment in biopharmaceutical product development is highly speculative because it entails substantial upfront capital expenditures and significant risk that any potential product candidate will fail to demonstrate adequate effect or an acceptable safety profile, gain regulatory approval or become commercially viable. Since inception, we have incurred significant operating losses. Our net losses were $93.9 million, $88.7 million and $62.1 million for the years ended December 31, 2022, 2021 and 2020 respectively, and we had an accumulated deficit of $376.7 million as of December 31, 2022. We have funded our operations to date 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. We have no products approved for commercial sale and have not generated any revenue from product sales to date, and we may never generate product revenue or achieve profitability.

•our ability to raise sufficient funds to support the development and potential commercialization of our product candidates;

•the outcomes and timing of regulatory reviews, approvals or other actions;

•our ability to obtain marketing approval for our product candidates;

•our ability to establish and maintain licensing, collaboration or similar arrangements on favorable terms and whether and to what extent we retain development or commercialization responsibilities under any new licensing, collaboration or similar arrangement;

•the success of any other business, product or technology that we acquire or in which we invest;

•our ability to maintain, expand and defend the scope of our intellectual property portfolio;

•our ability to manufacture any approved products on commercially reasonable terms;

•our ability to establish a sales and marketing organization or suitable third-party alternatives for any approved product;

•the number and characteristics of product candidates and programs that we pursue;

•hire additional clinical, regulatory and scientific personnel; and

•incur additional legal, accounting and other expenses associated with operating as a public company.

•seek new or additional collaborators for one or more of our current or future product candidates at an earlier stage than otherwise would be desirable or on terms that are less favorable than might otherwise be available; or

•relinquish or license on unfavorable terms our rights to technologies or product candidates that we otherwise would seek to develop or commercialize ourselves.

•the scope, number, initiation, progress, timing, costs, design, duration, any potential delays, and results of clinical trials and nonclinical studies for our current or future product candidates;

•the clinical development plans that we establish for these product candidates;

•the number and characteristics of product candidates and programs that we develop or may in-license;

•the outcome, timing and cost of regulatory reviews, approvals or other actions to meet regulatory requirements established by the U.S. Food and Drug Administration (“FDA”) and comparable foreign regulatory authorities, including the potential for the FDA or comparable foreign regulatory authorities to require that we perform more studies for our product candidates than those that we currently expect;

•our ability to obtain marketing approval for our product candidates;

•the cost of filing, prosecuting, defending and enforcing our patent claims and other intellectual property rights covering our product candidates, including any such patent claims and intellectual property rights that we have licensed from Genzyme pursuant to the terms of our license agreement with Genzyme or from other third parties;

•our ability to maintain, expand and defend the scope of our intellectual property portfolio, including the cost of defending intellectual property disputes, including patent infringement actions brought by third parties against us or our product candidates;

•the cost and timing of completion of commercial-scale manufacturing activities with respect to our product candidates;

•our ability to establish and maintain licensing, collaboration or similar arrangements on favorable terms and whether and to what extent we retain development or commercialization responsibilities under any new licensing, collaboration or similar arrangement;

•the cost of establishing sales, marketing and distribution capabilities for any product candidates for which we may receive regulatory approval in regions where we choose to commercialize our products on our own;

•the success of any other business, product or technology that we acquire or in which we invest;

•the costs of acquiring, licensing or investing in businesses, product candidates and technologies;

•our need and ability to hire additional management and scientific and medical personnel;

•market acceptance of our product candidates, to the extent any are approved for commercial sale;

•the effect of competing technological and market developments;

•the costs to operate as a public company; and

•business interruptions resulting from pandemics and public health emergencies, including those related to the ongoing COVID-19 pandemic, geopolitical actions, including war and terrorism or natural disasters including earthquakes, typhoons, floods and fires.

•successfully complete development activities, including all necessary nonclinical studies and clinical trials;

•complete and submit New Drug Applications to the FDA and obtain regulatory approval for indications for which there is a commercial market;

•complete and submit marketing applications to, and obtain regulatory approval from, foreign regulatory authorities;

•set and obtain a commercially viable price for our products;

•obtain commercial quantities of our products at acceptable cost levels;

•develop a commercial organization capable of sales, marketing and distribution for the products we intend to sell ourselves in the markets in which we have retained commercialization rights;

•find suitable collaborators to help us market, sell and distribute our approved products in other markets; and

•obtain coverage and adequate reimbursement from third-party, including government, payors.

•developing dosages that will be well-tolerated, safe and effective;

•completing the development and scale-up to permit manufacture of our product candidates in commercial quantities and at acceptable costs;

•demonstrating through pivotal clinical trials that each product candidate is safe and effective in patients for the intended indication;

•establishing commercial manufacturing capabilities or making arrangements with third-party manufacturers; and

•obtaining and maintaining patent and trade secret protection and non-patent exclusivity for our product candidates.

•disagreement with the design or implementation of our clinical trials;

•disagreement with the sufficiency of our clinical trials;

•failure to demonstrate the safety and efficacy of mavorixafor or any other product candidate for its proposed indications;

•failure to demonstrate that any clinical and other benefits of mavorixafor or any other product candidate outweigh its safety risks;

•a negative interpretation of the data from our nonclinical studies or clinical trials;

•deficiencies in the manufacturing or control processes or failure of third-party manufacturing facilities with which we contract for clinical and commercial supplies to comply with current Good Manufacturing Practice requirements, or cGMPs;

•insufficient data collected from clinical trials of mavorixafor or changes in the approval requirements that render its nonclinical and clinical data insufficient to support the filing of an NDA or to obtain regulatory approval; or

•changes in clinical practice in or approved products available for the treatment of the target patient population that could have an impact on the indications that we are pursuing for mavorixafor or our other product candidates.

•our obligation to pay Genzyme milestone payments in the aggregate amount of up to $25.0 million, contingent upon our achievement of certain late-stage regulatory and sales milestones with respect to licensed products.

•our obligation to pay Genzyme tiered royalties based on net sales of licensed products that we commercialize under the agreement.

•our obligation to pay Genzyme a certain percentage of cash payments received by us or our affiliates in consideration for the grant of a sublicense under the license granted to us by Genzyme.

Our license agreement with the Dana-Farber Cancer Institute (“DFCI”) imposes upon us various diligence, payment and other obligations, including our obligations to pay DFCI milestone payments in the aggregate amount of up to approximately $32 million, contingent upon our achievement of certain regulatory and sales milestones with respect to licensed products, to deliver reports at regular intervals and to maintain certain minimum levels of insurance. DFCI may terminate the agreement if (i) we cease to carry on our business with respect to the licensed products, (ii) we default on diligence, insurance, payment or any other material obligations, (iii) one of our officers or that of a sublicensee is convicted of a felony relating to the manufacture, use, sale or importation of one or more licensed product, (iv) we become insolvent, (v) we grant a sublicense without notifying DFCI or on terms inconsistent with the terms required of sublicenses under the agreement or (vi) we bring a patent challenge against the licensed products. We have the right to terminate the agreement for any reason upon 90 days advance written notice.

•the scope of rights granted under the applicable license agreement and other interpretation-related issues;

•whether and the extent to which our technology and processes infringe on intellectual property that is not subject to the applicable license agreement;

•our diligence obligations with respect to the use of the licensed technology under the applicable license agreement to develop and commercialize products and technologies, including the level of effort and specific activities that will satisfy those diligence obligations; and

•the ownership of inventions and know-how resulting from the joint creation or use of intellectual property by us and our collaborators.

•delay or failure in reaching agreement with the FDA or a comparable foreign regulatory authority on a trial design that we are able to execute;

•delay or failure in obtaining authorization to commence a trial or inability to comply with conditions imposed by a regulatory authority regarding the scope or design of a clinical trial;

•inability, delay or failure in identifying and maintaining a sufficient number of trial sites, many of which may already be engaged in competing clinical trial programs;

•delay or failure in recruiting and enrolling suitable subjects to participate in a trial;

•delay or failure in having subjects complete a trial or return for post-treatment follow-up;

•clinical sites and investigators deviating from trial protocol, failing to conduct the trial in accordance with regulatory requirements, or dropping out of a trial;

•delay or failure in reaching agreement on acceptable terms with prospective clinical research organizations (“CROs”) and clinical trial sites, the terms of which can be subject to extensive negotiation and may vary significantly among different CROs and trial sites;

•delay or failure in obtaining institutional review board (“IRB”) approval to conduct a clinical trial at each site;

•delays resulting from negative or equivocal findings of the Data Safety Monitoring Board (“DSMB”) if any;

•ambiguous or negative results;

•decision by the FDA, a comparable foreign regulatory authority, or recommendation by a DSMB to suspend or terminate clinical trials at any time for safety issues or for any other reason;

•inadequate drug product for use in nonclinical studies or clinical trials;

•lack of adequate funding to continue the product development program;

•external business disruptions affecting the initiation, patient enrollment, development and operation of our clinical trials, including a public health emergency, such as the COVID-19 pandemic, and unforeseen events such as the war in Ukraine; or

•changes in governmental regulations or requirements.

•issue warning letters;

•request modifications to promotional materials or require us to provide corrective information to healthcare practitioners;

•require us to enter into a consent decree, which can include imposition of various fines, reimbursements for inspection costs, required due dates for specific actions and penalties for noncompliance;

•seek an injunction or impose civil or criminal penalties or monetary fines;

•suspend or withdraw regulatory approval;

•suspend any ongoing clinical trials;

•refuse to approve pending applications or supplements to applications filed by us;

•suspend or impose restrictions on operations, including costly new manufacturing requirements; or

•seize or detain products, refuse to permit the import or export of products, or require us to initiate a product recall.

•the efficacy and safety of such product candidates as demonstrated in clinical trials;

•the clinical indications for which the product candidate is approved;

•acceptance by major operators of hospitals, physicians and patients of the product candidate as a safe and effective treatment, particularly the ability of mavorixafor and our other product candidates to establish themselves as a new standard of care in the treatment paradigm for the indications that we are pursuing;

•the potential and perceived advantages of our product candidates over alternative treatments as compared to the relative costs of the product candidates and alternative treatments;

•the prevalence and severity of any side effects with respect to our product candidates, including mavorixafor;

•our ability to offer any approved products for sale at competitive prices;

•the timing of market introduction of our products as well as competitive products;

•our pricing, and the availability of coverage and adequate reimbursement by third party payors and government authorities;

•relative convenience and ease of administration; and

•the effectiveness of our sales and marketing efforts and those of our potential future collaborators.

•regulatory authorities may withdraw or limit their approval of such product candidates;

•regulatory authorities may require the addition of labeling statements, such as a “boxed” warning or a contraindication;

•we may be required to create a medication guide outlining the risks of such side effects for distribution to patients;

•we may be required to change the way such product candidates are distributed or administered, conduct additional clinical trials or change the labeling of the product candidates;

•regulatory authorities may require a Risk Evaluation and Mitigation Strategy plan to mitigate risks, which could include medication guides, physician communication plans, or elements to assure safe use, such as restricted distribution methods, patient registries and other risk minimization tools;

•we may be subject to regulatory investigations and government enforcement actions;

•we may decide to remove such product candidates from the marketplace after they are approved;

•we could be sued and held liable for injury caused to individuals exposed to or taking our product candidates; and

•our reputation may suffer.

•restrictions on such products, manufacturers or manufacturing processes;

•restrictions on the labeling, marketing, distribution or use of a product;

•requirements to conduct post-approval clinical trials;

•warning or untitled letters;

•withdrawal of the products from the market;

•refusal to approve pending applications or supplements to approved applications that we submit;

•recall of products;

•fines, restitution or disgorgement of profits or revenue;

•suspension or withdrawal of marketing approvals;

•refusal to permit the import or export of our products;

•product seizure; and

•injunctions or the imposition of civil or criminal penalties.

•our inability to recruit and retain adequate numbers of effective sales and marketing personnel;

•the inability of sales personnel to obtain access to physicians or educate adequate numbers of physicians on the benefits of prescribing any future products; and

•unforeseen costs and expenses associated with creating an independent sales and marketing organization.

•different regulatory requirements for approval of therapies in foreign countries;

•reduced protection for intellectual property rights;

•unexpected changes in tariffs, trade barriers and regulatory requirements;

•economic weakness, including inflation, or political instability in particular foreign economies and markets;

•compliance with tax, employment, immigration and labor laws for employees living or traveling abroad;

•foreign currency fluctuations, which could result in increased operating expenses and reduced revenues, and other obligations incident to doing business in another country;

•foreign reimbursement, pricing and insurance regimes;

•workforce uncertainty in countries where labor unrest is more common than in the United States;

•production shortages resulting from any events affecting raw material supply or manufacturing capabilities abroad; and

•business interruptions resulting from geopolitical actions, including war and terrorism, or natural disasters and public health epidemics, such as the ongoing COVID-19 pandemic.

•reduced resources of our management to pursue our business strategy;

•decreased demand for any products that we may develop;

•injury to our reputation and significant negative media attention;

•withdrawal of clinical trial participants;

•significant costs to defend any related litigation;

•substantial monetary awards to trial participants or patients;

•loss of revenue;

•increased insurance costs; and

•the inability to commercialize any products that we may develop.

•the federal Anti-Kickback Statute prohibits, among other things, persons and entities from knowingly and willfully soliciting, offering, receiving or paying remuneration, directly or indirectly, in cash or in kind, to induce or reward, or in return for, either the referral of an individual for, or the purchase, order or recommendation of, any good or service, for which payment may be made under a federal healthcare program such as Medicare and Medicaid; a person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation;

•the federal false claims laws impose criminal and civil penalties, including civil whistleblower or qui tam actions, against individuals or entities for, among other things, knowingly presenting, or causing to be presented, to the federal government, claims for payment that are false or fraudulent or making a false statement to avoid, decrease or conceal an obligation to pay money to the federal government; in addition, the government may assert that a claim including items and services resulting from a violation of the federal Anti-Kickback Statute constitutes a false or fraudulent claim for purposes of the False Claims Act;

•the federal Health Insurance Portability and Accountability Act of 1996 (“HIPAA”) imposes criminal and civil liability for, among other things, executing a scheme to defraud any healthcare benefit program, or knowingly and willfully falsifying, concealing or covering up a material fact or making any materially false statement in connection with the delivery of or payment for healthcare benefits, items or services; similar to the federal Anti-Kickback Statute, a person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation;

•the federal physician payment transparency requirements, sometimes referred to as the “Sunshine Act” under the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act of 2010 (collectively the “ACA”), require certain manufacturers of drugs, devices, biologics and medical supplies that are reimbursable under Medicare, Medicaid, or the Children’s Health Insurance Program to report to the Centers for Medicare & Medicaid Services (“CMS”), information related to payments and other transfers of value to physicians, (defined to include doctors, dentists, optometrists, podiatrists and chiropractors), certain other healthcare professionals (such as physician assistants and nurse practitioners), and teaching hospitals and the ownership and investment interests of physicians and their immediate family members in such manufacturers;

•HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act and its implementing regulations, which also imposes obligations on certain covered entity healthcare providers, health plans, and healthcare clearinghouses as well as their business associates that perform certain services involving the use or disclosure of individually identifiable health information, and their subcontractors that use, disclose, or otherwise process individually identifiable health information, including mandatory contractual terms, with respect to safeguarding the privacy, security and transmission of individually identifiable health information;

•analogous state and foreign laws and regulations, such as state anti-kickback and false claims laws, may apply to sales or marketing arrangements and claims involving healthcare items or services reimbursed by non-governmental third-party payors, including private insurers;

•some state laws require pharmaceutical companies to comply with the pharmaceutical industry’s voluntary compliance guidelines and the relevant compliance guidance promulgated by the federal government and may require drug manufacturers to report information related to payments and other transfers of value to physicians and other healthcare providers, drug pricing or marketing expenditures;

•state and local laws that require the registration of pharmaceutical sales representatives; and

•state and foreign laws also govern the privacy and security of health information in certain circumstances, many of which differ from each other in significant ways and often are not preempted by HIPAA, thus complicating compliance efforts.

•an annual, nondeductible fee on any entity that manufactures or imports specified branded prescription drugs and biologic products;

•an increase in the statutory minimum rebates a manufacturer must pay under the Medicaid Drug Rebate Program;

•expansion of healthcare fraud and abuse laws, including the False Claims Act and the Anti-Kickback Statute, new government investigative powers, and enhanced penalties for noncompliance;

•a new Medicare Part D coverage gap discount program, in which manufacturers must agree to offer 70% point-of-sale discounts off negotiated prices;

•extension of manufacturers’ Medicaid rebate liability;

•expansion of eligibility criteria for Medicaid programs;

•expansion of the entities eligible for discounts under the Public Health Service Act’s pharmaceutical pricing program;

•new requirements to report to CMS financial arrangements with physicians, as defined by such law, and teaching hospitals;

•a new requirement to annually report to FDA drug samples that manufacturers and distributors provide to physicians; and

•a new Patient-Centered Outcomes Research Institute to oversee, identify priorities in, and conduct comparative clinical effectiveness research, along with funding for such research.

•collaborators have significant discretion in determining the efforts and resources that they will apply to these collaborations;

•collaborators may not pursue development and commercialization of our product candidates or may elect not to continue or renew development or commercialization programs based on clinical trial results, changes in the collaborator’s strategic focus or available funding or external factors such as an acquisition that diverts resources or creates competing priorities;

•collaborators may delay clinical trials, provide insufficient funding for a clinical trial program, stop a clinical trial or abandon a product candidate, repeat or conduct new clinical trials or require a new formulation of a product candidate for clinical testing;

•collaborators could independently develop, or develop with third parties, products that compete directly or indirectly with our product candidates or products if the collaborators believe that competitive products are more likely to be successfully developed or can be commercialized under terms that are more economically attractive than ours;

•collaborators with marketing and distribution rights to one or more product candidates or products may not commit sufficient resources to the marketing and distribution of such drugs;

•collaborators may not properly maintain or defend our intellectual property rights or may use our proprietary information in such a way as to invite litigation that could jeopardize or invalidate our proprietary information or expose us to potential litigation;

•disputes may arise between the collaborators and us that result in the delay or termination of the research, development or commercialization of our product candidates or products or that result in costly litigation or arbitration that diverts management attention and resources;

•we may lose certain valuable rights under circumstances identified in our collaborations if we undergo a change of control;

•collaborations may be terminated and, if terminated, may result in a need for additional capital to pursue further development or commercialization of the applicable product candidates; and

•collaboration agreements may not lead to development or commercialization of product candidates in the most efficient manner or at all. In addition, if a future collaborator of ours were to be involved in a business combination, the continued pursuit and emphasis on our product development or commercialization program under such collaboration could be delayed, diminished or terminated.

•the scope of rights granted under the license agreement and other interpretation-related issues;

•the extent to which our product candidates, technology and processes infringe on intellectual property of the licensor that is not subject to the licensing agreement;

•the sublicensing of patent and other rights under our collaborative development relationships;

•our diligence obligations under the license agreement and what activities satisfy those diligence obligations;

•the inventorship and ownership of inventions and know-how resulting from the joint creation or use of intellectual property by our licensors and us and our partners; and

•the priority of invention of patented technology.

•managing our clinical trials effectively;

•identifying, recruiting, maintaining, motivating and integrating additional employees;

•managing our internal development efforts effectively while complying with our contractual obligations to licensors, contractors and other third parties;

•improving our managerial, development, operational and finance systems; and

•expanding our facilities.

•sell, transfer, lease or dispose of certain assets;

•incur indebtedness;

•encumber or permit liens on certain assets;

•make certain investments;

•make certain restricted payments, including paying dividends on, or repurchasing or making distributions with respect to, our common stock; and

•enter into certain transactions with affiliates.

•our ability or the ability of our collaborators to develop product candidates and conduct clinical trials that demonstrate such product candidates are safe and effective;

•our ability or the ability of our collaborators to obtain regulatory approvals for product candidates, and delays or failures to obtain such approvals;

•failure of any our product candidates to demonstrate safety and efficacy, receive regulatory approval and achieve commercial success;

•failure to maintain our existing third-party license, manufacturing and supply agreements;

•failure by us or our licensors to prosecute, maintain or enforce our intellectual property rights;

•changes in laws or regulations applicable to our current or future product candidates;

•any inability to obtain adequate supply of product candidates or the inability to do so at acceptable prices;

•adverse decisions by regulatory authorities;

•introduction of new or competing products by our competitors;

•failure to meet or exceed financial and development projections that we may provide to the public;

•the perception of the pharmaceutical industry by the public, legislatures, regulators and the investment community;

•announcements of significant acquisitions, strategic collaborations, joint ventures or capital commitments by us or our competitors;

•disputes or other developments relating to proprietary rights, including patents, litigation matters and our ability to obtain intellectual property protection for our technologies;

•additions or departures of key personnel;

•significant lawsuits, including intellectual property or stockholder litigation;

•announcements by us of material developments in our business, financial condition and/or operations;

•if securities or industry analysts do not publish research or reports about us, or if they issue an adverse or misleading opinions regarding our business and stock;

•changes in the market valuations of similar companies;

•general macroeconomic, political and market conditions and overall fluctuations in the financial markets in the United States and abroad;

•sales of our common stock or our stockholders in the future;

•trading volume of our common stock;

•adverse publicity relating to our markets generally, including with respect to other products and potential products in such markets;

•changes in the structure of health care payment systems;

•period-to-period fluctuations in our financial results; and

•the other factors described in this “Risk Factors” section and elsewhere in this Annual Report

Sales of a substantial number of shares of our common stock in the public market, or the perception that these sales might occur, could depress the market price of our common stock and could impair our ability to raise capital through the sale of additional equity securities. We are unable to predict the effect that sales, particularly sales by our directors, executive officers, and significant stockholders, may have on the prevailing market price of our common stock.

ITEM 5.     MARKET FOR REGISTRANT'S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

ITEM 7.     MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following table summarizes the results of our operations for the periods indicated:

			Year Ended December 31,
			2022						2021						Change
			(in thousands)
Operating expenses:
Research and development			$	61,058					$	50,647					$	10,411
Selling, general and administrative			27,020						24,702						2,318
Gain on sale of non-financial asset			(509)						—						(509)
Impairment of goodwill			—						9,758						(9,758)
Total operating expenses			87,569						85,107						2,462
Loss from operations			(87,569)						(85,107)						(2,462)
Total other expense, net			(6,270)						(3,572)						(2,698)
Loss before provision for income taxes			(93,839)						(88,679)						(5,160)
Provision for income taxes			28						17						11
Net loss			$	(93,867)					$	(88,696)					$	(5,171)

			Year Ended December 31,
			2022						2021						Change
			(in thousands)
Direct research and development expenses by product candidate:
Mavorixafor (X4P-001)			$	30,041					$	25,400					$	4,641
X4P-002			2,338						1,130						1,208
X4P-003			206						1,370						(1,164)
Unallocated expense			28,473						22,747						5,726
Total research and development expenses			$	61,058					$	50,647					$	10,411

Selling, General and Administrative Expenses  

Other Expense, Net  

			Year Ended December 31,
			2022						2021						Change
			(in thousands)
Interest income			$	219					$	10					$	209
Interest expense			(3,993)						(3,642)						(351)
Change in fair value of warrant and derivative liabilities			1,701						(366)						2,067
Research and development incentive program			534						789						(255)
Foreign currency losses, issuance costs related to warrants and other			(4,731)						(363)						(4,368)
Total other expense, net			$	(6,270)					$	(3,572)					$	(2,698)

Income Taxes   

ATM Sales Agreement — We have entered into a Controlled Equity OfferingSM Sales Agreement (“ATM Sales Agreement”), with B. Riley Securities, Inc., Cantor Fitzgerald & Co., and Stifel, Nicolaus & Company, Incorporated (collectively the “Sales Agents”), pursuant to which we may offer and sell, at our sole discretion through one or more of the Sales Agents, shares of our common stock having an aggregate offering price of up to $50 million. To date, we have sold approximately $14.3 million of our common stock, net of offering costs, under the ATM Sales Agreement.

LPC Agreement — In January 2022, we entered into an agreement, (the “LPC Agreement”) with Lincoln Park Capital Fund LLC (“Lincoln Park”), pursuant to which we have the right to sell to Lincoln Park shares of our common stock, having an aggregate value of up to $50.0 million, subject to certain limitations and conditions, at our request during a 36-month period. The shares of common stock that we may sell under the LPC Agreement are capped at 5.6 million, which amount may be adjusted under certain conditions as defined in the LPC Agreement. In January 2022, we raised $3.0 million from the sale of shares of our common stock through the LPC Agreement.

Public and Private Equity Offerings — Over the past several years we have funded our operations primarily from sales of common stock, warrants and prefunded warrants through both public offerings and private placements. In March 2021, we sold shares of common stock, redeemable common stock, and, in lieu of common stock, pre-funded warrants to purchase shares of common stock in a private placement for gross proceeds of $55.0 million, before offering expenses and $2 million paid for the subsequent settlement of redeemable common stock in August 2021. In November 2021, we raised approximately $10.0 million through the sale of pre-funded warrants to an investor in a private placement. In March 2022, we sold shares of common stock and, in lieu of common stock, pre-funded warrants to purchase shares of common stock in a private placement for gross proceeds of $3.0 million, before offering expenses. In June 2022, we sold shares of common stock and, in lieu of common stock, pre-funded warrants to purchase shares of common stock in a private placement for gross proceeds of $55.7 million, before offering expenses. In December 2022, we sold shares of common stock and, in lieu of common stock, pre-funded warrants to purchase shares of common stock in a public offering for gross proceeds of $65.1 million, before offering expenses.

Hercules Loan Agreement — In January 2023, we entered into a Second Amended and Restated Loan and Security Agreement (the “Hercules Loan Agreement”) with Hercules Capital, Inc., as agent and lender, and Hercules Capital Funding IV LLC and Hercules Capital Funding Trust 2022-1, as lenders (collectively, “Hercules”), which agreement amended and restated the Amended and Restated Loan and Security Agreement dated as of June 27, 2019, as subsequently amended from time to time (the “Previous Loan Agreement”). The Hercules Loan Agreement provides for a term loan of $32.5 million and an interest-only payment period through October 1, 2024, provided however, if certain conditions are met, then the interest-only payment period will be extended to January 1, 2026. To date, we have borrowed the full $32.5 million under the Hercules Loan Agreement, and such amount remains outstanding as of December 31, 2022.

Going Concern— Since our inception, we have incurred significant operating losses and negative cash flows from our operations. We have not yet commercialized any products and we do not expect to generate revenue from sales of any products for several years, if at all. As of December 31, 2022, our cash and cash equivalents were $121.7 million and our restricted cash balance was $1.3 million. We have a covenant under our Hercules Loan Agreement that currently requires that we maintain a minimum level of cash of $20.0 million, subject to reduction to $10 million upon the achievement of operational milestones. Based on our current financial projections and with no additional funding, we believe we will not be able to maintain the minimum cash required to satisfy this covenant beginning in the first quarter of 2024. In such event, the lenders could require the repayment of all outstanding debt.

The following table summarizes our cash flow activities for each of the periods presented:

			Year Ended December 31,
			2022						2021
			(in thousands)
Net loss			$	(93,867)					$	(88,696)
Adjustments to reconcile net loss to net cash used in operating activities			11,029						19,289
Changes in operating assets and liabilities			5,736						(1,498)
Net cash used in operating activities			(77,102)						(70,905)
Net cash used in investing activities			(103)						(615)
Net cash provided by financing activities			117,230						74,245
Impact of foreign exchange on cash and restricted cash			(105)						(319)
Net increase in cash, cash equivalents and restricted cash			39,920						2,406
Cash, cash equivalents and restricted cash, beginning of period			83,108						80,702
Cash, cash equivalents and restricted cash, end of period			$	123,028					$	83,108

Operating Activities:  During the year ended December 31, 2022, net cash used in operating activities was $77.1 million, primarily resulting from our net losses of $93.9 million, adjusted for noncash expenses of $11.0 million and changes in our operating assets and liabilities of $5.7 million. Noncash expenses primarily includes stock-based compensation expense of $5.2 million. The change in operating assets and liabilities was primarily due to an increase in accounts payable and accrued expenses due to the timing of payments related to our CROs. Cash used in operating activities was higher for the year ended December 31, 2022 as compared to the prior year primarily due to higher net losses in the current year.

Financing Activities:   During the year ended December 31, 2022, net cash provided by financing activities was $117.2 million, consisting primarily of net proceeds from two private placements and a public offering of our common stock, warrants, and pre-funded warrants. During the year ended December 31, 2021, net cash provided by financing activities was $74.2 million, consisting primarily of proceeds from the sale of our common stock and pre-funded warrants in a private placement.

In October 2018, we entered into a Loan and Security Agreement, as subsequently amended from time to time, with Hercules. On January 6, 2023, we entered into the Hercules Loan Agreement, which amended and restated the previous loan and security agreement. Under the Hercules Loan Agreement, we have borrowed the maximum aggregate principal of $32.5 million of the term loan. Borrowings under the Hercules Loan Agreement accrue interest at a variable rate equal to the greater of (i) 10.15%, or (ii) The Wall Street Journal prime rate plus 3.15%.  In an event of default, and until such event is no longer continuing, the interest rate applicable to borrowings would be increased by 4.0%.

•the scope, number, initiation, progress, timing, costs, design, duration, any potential delays, and results of clinical trials and nonclinical studies for our current or future product candidates, particularly our Phase 2 clinical trial of mavorixafor for the treatment of patients with chronic neutropenic disorders;

•the outcome, timing and cost of regulatory reviews, approvals or other actions to meet regulatory requirements established by the FDA and comparable foreign regulatory authorities, including the potential for the FDA or comparable foreign regulatory authorities to require that we perform more studies for our product candidates than those that we currently expect;

•our ability to obtain marketing approval for our product candidates;

•the cost of filing, prosecuting, defending and enforcing our patent claims and other intellectual property rights covering our product candidates, including any such patent claims and intellectual property rights that we have licensed from Genzyme pursuant to the terms of our license agreement with Genzyme;

•our ability to maintain, expand and defend the scope of our intellectual property portfolio, including the cost of defending intellectual property disputes, including patent infringement actions brought by third parties against us or our product candidates;

•the cost and timing of completion of commercial-scale manufacturing activities with respect to our product candidates;

•our ability to establish and maintain licensing, collaboration or similar arrangements on favorable terms and whether and to what extent we retain development or commercialization responsibilities under any new licensing, collaboration or similar arrangement;

•the cost of establishing sales, marketing and distribution capabilities for any product candidates for which we may receive regulatory approval in regions where we choose to commercialize our products on our own;

•the success of any other business, product or technology that we acquire or in which we invest;

•the costs of acquiring, licensing or investing in businesses, product candidates and technologies;

•our need and ability to hire additional management and scientific and medical personnel;

•market acceptance of our product candidates, to the extent any are approved for commercial sale;

•the effect of competing technological and market developments; and

•the costs to operate as a public company

Until such time, if ever, as we can generate substantial product revenue, we expect to finance our cash needs through a combination of equity offerings, debt financings, collaborations, strategic alliances, and marketing, distribution or licensing arrangements with third parties. We have effective universal shelf registration statements on Form S-3 registering the sale of our common stock, warrants to purchase our common stock and other securities on terms that we may determine. We have an ATM Sales Agreement with the Sales Agents, pursuant to which we have offered to sell and continue to offer to sell, at our sole discretion through one or more of the Sales Agents, shares of our common stock. We have entered into a common stock purchase agreement with Lincoln Park Capital, pursuant to which Lincoln Park Capital has committed to purchase, at our request from time to time over a 36-month period, shares of our common stock having an aggregate offering price of up to $50.0 million, of which $3.0 million have been sold to date, subject to certain limitations.

Accrued Research and Development Expenses.    As part of the process of preparing our consolidated financial statements, we are required to estimate our accrued research and development expenses. This process involves reviewing open contracts and purchase orders, communicating with our applicable personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of actual costs. The majority of our service providers invoice us in arrears for services performed, on a pre-determined schedule or when contractual milestones are met; however, some require advance payments. We make estimates of our accrued expenses as of each balance sheet date in the consolidated financial statements based on facts and circumstances known to them at that time. For our significant vendors, we confirm the accuracy of these estimates with the service providers and make adjustments, if necessary. Examples of estimated accrued research and development expenses include fees paid to:

•vendors in connection with preclinical development activities;

•CROs and investigative sites in connection with preclinical studies and clinical trials; and

•CMOs in connection with the production of preclinical and clinical trial materials.

Stock-Based Compensation.   We measure all stock-based awards granted to employees, directors and consultants based on the grant-date fair value of the award and recognized compensation expense, net of estimated forfeitures, over the requisite service period, which is generally the vesting period of the respective award. The stock-based awards that we have issued to date include a service-based vesting condition and the expense for these awards is recognized using the straight-line method. We have also issued stock-based awards with performance-based vesting conditions that vest in part upon our achievement of operational milestones and over time thereafter for the subsequent two years as the employee continues to provide services. We assess the probability of achievement of these operational milestones and recognize stock-based compensation for these awards using the accelerated attribution model based on the fair value of the awards as of the date of grant and our best estimate of the date each operational milestone will be achieved. We update our estimates related to the probability and timing of achievement of the operational milestones each period until the award either vests or is forfeited.

Goodwill. Business combinations are accounted for under the acquisition method. The total purchase price of an acquisition is allocated to the underlying identifiable net assets, based on their respective estimated fair values as of the acquisition date. Determining the fair value of assets acquired and liabilities assumed requires management’s judgment and often involves the use of significant estimates and assumptions, including assumptions with respect to future cash inflows and outflows, probabilities of success, discount rates, and asset lives, among other items. Assets acquired and liabilities assumed are recorded at their estimated fair values. The excess of the purchase price over the estimated fair values of the net assets acquired is recorded as goodwill.

ITEM 9.     CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURES

•pertain to the maintenance of records that in reasonable detail accurately and fairly reflect the transactions and dispositions of the assets of the company;

•provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and

•provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of the company’s assets that could have a material effect on the financial statements.

Management conducted an assessment of our internal controls over financial reporting based on the framework established by the Committee of Sponsoring Organizations of the Treadway Commission in Internal Control-Integrated Framework (2013). Based on the assessment, management concluded that, as of December 31, 2022, our internal control over financial reporting was effective.

ITEM 12.     SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS

ITEM 13.     CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE

ITEM 15.     EXHIBIT AND FINANCIAL STATEMENT SCHEDULES

									Page
Report of Independent Registered Public Accounting Firm									F-2
PricewaterhouseCoopers LLP			Boston, MA			(Firm ID 238)
Consolidated Balance Sheets									F-3
Consolidated Statements of Operations and Comprehensive Loss									F-4
Consolidated Statements of Redeemable Common Stock and Stockholders’ Equity									F-5
Consolidated Statements of Cash Flows									F-6
Notes to Consolidated Financial Statements									F-7

Exhibit No.						Exhibit Description						Form			Exhibit			Date						Se File/ Ref No.
3.1						Restated Certificate of Incorporation, as amended, as of September 1, 2022						8-K			3.1			9/1/2022						001-38295
3.2						Amended and Restated By-laws of the Company						8-K			3.2			11/20/2017						001-38295
4.1						Form of Common Stock Certificate						8-K			4.1			3/13/2019						001-38295
4.2						Form of Warrant to Purchase Common Stock of the Company (formerly Series A Preferred Stock of X4 Therapeutics, Inc. (formerly X4 Pharmaceuticals, Inc.)) issued to Silicon Valley Bank and Life Science Loans, LLC.						8-K			4.2			3/13/2019						001-38295
4.3						Form of Warrant to Purchase Common Stock of the Company (formerly Series A Preferred Stock of X4 Therapeutics, Inc. (formerly X4 Pharmaceuticals, Inc.)) issued to Maxim Partners LLC.						8-K			4.3			3/13/2019						001-38295
4.4						Form of Warrant to Purchase Common Stock of the Company (formerly Series B Preferred Stock of X4 Therapeutics, Inc. (formerly X4 Pharmaceuticals, Inc.)).						8-K			4.4			3/13/2019						001-38295
4.5						Form of Warrant to Purchase Common Stock of the Company (formerly Series B Preferred Stock of X4 Therapeutics, Inc. (formerly X4 Pharmaceuticals, Inc.)) issued to Hercules Capital, Inc.						8-K			4.5			3/13/2019						001-38295
4.6						Warrant Modification Agreement, dated as of December 11, 2018, with Hercules Capital, Inc.						8-K			4.6			3/13/2019						001-38295
4.7						Form of Prefunded Warrant.						8-K			4.1			04/12/2019						001-38295
4.8						Form of Class A Warrant						8-K			4.2			04/12/2019						001-38295
4.9						Form of Prefunded Warrant						8-K			4.1			11/29/2019						001-38295
4.10						Securities Purchase Agreement, dated March 18, 2021, by and among X4 Pharmaceuticals, Inc. and the persons party thereto.						8-K			10.1			3/19/2019						001-38295
4.11						Registration Rights Agreement, dated March 18, 2021, by and among X4 Pharmaceuticals, Inc. and the persons party thereto.						8-K			10.2			3/19/2019						001-38295

4.12						Form of March 2021 Prefunded Warrant						8-K			4.1			3/19/2019						001-38295
4.13						Securities Purchase Agreement, dated November 5, 2021, by and among X4 Pharmaceuticals, Inc. and the persons party thereto.						8-K			10.1			11/5/2021						001-38295
4.14						Registration Rights Agreement, dated November 5, 2021, by and among X4 Pharmaceuticals, Inc. and the persons party thereto.						8-K			10.2			11/5/2021						001-38295
4.15						Form of November 2021 Prefunded Warrant						8-K			4.1			11/5/2021						001-38295
4.16						Controlled Equity OfferingSM Sales Agreement, dated as of August 7, 2020, by and between X4 Pharmaceuticals, Inc. and B. Riley Securities, Inc., Cantor Fitzgerald & Co. and Stifel, Nicolaus & Company, Incorporated.						S-3			1.2			8/7/2020						001-38295
4.17*						Description of Registered Securities
4.18						Form of March 2022 Prefunded Warrant						8-K			4.1			3/3/2022						001-38295
4.19						Securities Purchase Agreement, dated March 3, 2022, by and among X4 Pharmaceuticals, Inc. and the persons party thereto.						8-K			10.1			3/3/2022						001-38295
4.20						Registration Rights Agreement, dated March 3, 2022, by and among X4 Pharmaceuticals, Inc. and the persons party thereto.						8-K			10.2			3/3/2022						001-38295
4.21						Purchase Agreement, dated as of January 14, 2022, by and between X4 Pharmaceuticals, Inc. and Lincoln Park Capital Fund, LLC.						8-K			10.1			1/14/2022						001-38295
4.22						Registration Rights Agreement, dated as of January 14, 2022, by and between X4 Pharmaceuticals, Inc. and Lincoln Park Capital Fund, LLC.						8-K			10.2			1/14/2022						001-38295
4.23						Securities Purchase Agreement, dated June 30, 2022, by and among X4 Pharmaceuticals Inc. and the persons party thereto.						8-K			10.1			7/1/2022						001-38295
4.24						Registration Rights Agreement, dated June 30, 2022, by and among X4 Pharmaceuticals Inc. and the persons party thereto.						8-K			10.2			7/1/2022						001-38295
4.25						Form of July 2022 Pre-Funded Warrant						8-K			4.1			7/1/2022						001-38295
4.26						Form of July 2022 Warrant						8-K			4.2			7/1/2022						001-38295
4.27						Form of December 2022 Pre-Funded Warrant						8-K			4.1			12/9/2022						001-38295
4.28						Form of Class C Warrant.						8-K			4.2			12/9/2022						001-38295
10.1@						2015 Employee, Director and Consultant Equity Incentive Plan, as amended.						8-K			10.1.1			3/13/2019						001-38295
10.2@						Form of Stock Option Agreement under the 2015 Employee, Director and Consultant Equity Incentive Plan, as amended.						8-K			10.1.2			4/2/2019						001-38295
10.3@						Form of Restricted Stock Unit Agreement under the 2015 Employee, Director and Consultant Equity Incentive Plan, as amended						8-K			10.6			6/17/2019						001-38295
10.4@						Amended and Restated 2017 Equity Incentive Plan						S-8			99.1			6/10/2020						333-239082
10.5@						Form of Incentive Stock Option Agreement under the 2017 Equity Incentive Plan						S-1			10.8			10/20/2017						001-38295
10.6@						Form of Nonstatutory Stock Option Agreement under the 2017 Equity Incentive Plan						S-1			10.9			10/20/2017						001-38295
10.7@						Form of Restricted Stock Agreement under the 2017 Equity Incentive Plan						8-K			10.6			11/27/2018						001-38295
10.8@						Form of Restricted Stock Unit Agreement under the 2017 Equity Incentive Plan						8-K			10.5			6/19/2019						001-38295
10.9@						Form of Performance-Based Restricted Stock Unit						S-8			99.6			6/10/2020						333-239082
10.10@						2017 Employee Stock Purchase Plan						S-1			10.10			10/20/2017						001-38295
10.11@						X4 Pharmaceuticals, Inc. 2019 Inducement Equity Incentive Plan						8-K			10.1			12/23/2022						001-38295

10.12@

Form of Stock Option Agreement under the 2019 Inducement Equity Incentive Plan

8-K

10.2

6/17/2019

001-38295

10.13@

Form of Restricted Stock Agreement under the 2019 Inducement Equity Incentive Plan

8-K

10.3

6/17/2019

001-38295

10.14@

Form of Restricted Stock Unit Agreement under the 2019 Inducement Equity Incentive Plan

8-K

10.4

6/17/2019

001-38295

10.15@

Form of Indemnification Agreement (for directors and executive officers)

S-1/A

10.36

11/06/2017

001-38295

10.16@*

Director Compensation Policy

10.17@

Amended and Restated Executive Employment Agreement, dated as of March 13, 2019, by and between the Company and Paula Ragan, Ph.D.

8-K

10.3

3/13/2019

001-38295

10.18@

Amendment to Amended and Restated Executive Employment Agreement, dated as of March 13, 2019, dated February 13, 2020 by and between the Company and Paula Ragan, Ph.D.

10-Q

10.1

3/31/2020

001-38295

10.19@

Second Amended and Restated Executive Employment Agreement, dated as of March 7, 2022 by and between the Company and Adam S. Mostafa.

10-K

10.19

3/17/2022

001-38295

10.20@

Amended and Restated Executive Employment Agreement, dated as of March 7, 2022 by and between the Company and Mary DiBiase

10-K

10.23

3/17/2022

001-38295

10.21@*

Executive Employment Agreement, dated as of November 14, 2022, by and between the Company and Murray Stewart

10.22#

License Agreement, dated as of July 10, 2014, by and between X4 Therapeutics, Inc. (formerly X4 Pharmaceuticals, LLC) and Genzyme Corp., a Sanofi company.

8-K

10.5#

3/13/2019

001-38295

10.23#

Amendment No. 1 to License Agreement, dated as of October 23, 2014, by and between X4 Therapeutics, Inc. (formerly X4 Pharmaceuticals, Inc.) and Genzyme Corporation, a Sanofi company.

8-K/A

10.6#

5/13/2019

001-38295

10.24#

License Agreement, dated as of December 13, 2016, by and between X4 Therapeutics, Inc. (formerly X4 Pharmaceuticals, Inc.) and Georgetown University.

8-K/A

10.7#

5/13/2019

001-38295

10.25#

Exclusive License Agreement, dated as of December 23, 2016, by and between X4 Therapeutics, Inc. (formerly X4 Pharmaceuticals, Inc.) and Beth Israel Deaconess Medical Center.

8-K/A

10.8#

5/13/2019

001-38295

10.26

License Agreement, dated as of November 13, 2020, by and between X4 Pharmaceuticals Inc. and the Dana Farber Cancer Institute.

10-K

10.33

3/19/2021

001-38295

10.27*+

Second Amended and Restated Loan and Security Agreement, dated as of January 6, 2023, by and among X4 Pharmaceuticals, Inc., X4 Therapeutics, Inc., Hercules Capital, Inc. and Hercules Capital Funding IV LLC and Hercules Capital Funding Trust 2022-1

10.28

Lease, dated as of November 11, 2019, by and between X4 Pharmaceuticals Inc. and Beacon North Village, LLC.

10-K

10.32

3/12/2020

001-38295

10.29

Settlement Agreement, dated as of March 8, 2019, by and among X4 Pharmaceuticals, Inc. (formerly Arsanis, Inc.), Artemis AC Corp., X4 Therapeutics, Inc. (formerly X4 Pharmaceuticals, Inc.), Arsanis Biosciences GmbH and Österreichische Forschungsförderungsgesellschaft GmbH.

8-K

10.1

4/11/2019

001-38295

10.30

Master Services Agreement, dated September 10, 2015, by and between X4 Pharmaceuticals Inc. and Mayne Pharma Inc. (formerly known as Metrics, Inc.).

10-K

10.35

3/12/2020

001-38295

10.31

Amendment No. 1 to Master Services Agreement, dated August 25, 2017, by and between X4 Pharmaceuticals Inc. and Mayne Pharma Inc. (formerly known as Metrics, Inc.)

10-K

10.36

3/12/2020

001-38295

10.32

Amendment No. 2 to Master Services Agreement, dated February 28, 2020, by and between X4 Pharmaceuticals Inc. and Mayne Pharma Inc.

10-K

10.37

3/12/2020

001-38295

10.33

Master Services Agreement, dated February 19, 2016, by and between X4 Pharmaceuticals Inc. and Aptuit (Oxford) Limited

10-K

10.38

3/12/2020

001-38295

10.34

Amendment No. 1 to Master Services Agreement, dated February 19, 2016, by and between X4 Pharmaceuticals Inc. and Aptuit (Oxford) Limited

10-K

10.39

3/12/2020

001-38295

10.35

Amendment No. 2 to Master Services Agreement, dated February 19, 2021, by and between X4 Pharmaceuticals Inc. and Aptuit (Oxford) Limited.

10-K

10.48

3/19/2021

001-38295

10.36@

Form of Stock Appreciation Right Agreement under the X4 Pharmaceuticals, Inc. Amended and Restated 2017 Equity Incentive Plan.

8-K

10.1

11/9/2022

001-38295

21.1

List of Subsidiaries

10-K

21.1

3/17/2022

001-38295

23.1*

Consent of PricewaterhouseCoopers LLP, Independent Registered Public Accounting Firm

31.1*

Certification of the Chief Executive Officer, as required by Section 302 of the Sarbanes-Oxley Act of 2002

31.2*

Certification of the Chief Financial Officer, as required by Section 302 of the Sarbanes-Oxley Act of 2002

32.1**

Certification of the Chief Executive Officer and Chief Financial Officer, as required by Section 906 of the Sarbanes-Oxley Act of 2002

101.INS

XBRL Instance Document

101.SCH

XBRL Taxonomy Extension Schema Document

101.CAL

SXRL Taxonomy Extension Calculation Linkbase Document

101.DEF

XBRL Taxonomy Extension Definition Linkbase Document

101.LAB

XBRL Taxonomy Extension Label Linkbase Document

101.PRE

XBRL Taxonomy Extension Presentation Linkbase Document

104

Cover Page Interactive Data File (formatted as Inline XBRL)

*Filed herewith

#    Certain confidential portions of this Exhibit were omitted by means of marking such portions with brackets (“[***]”) because the identified confidential portions (i) are not material and (ii) is the type of information that the Registrant treats as private or confidential.    

+ Certain schedules and exhibits have been omitted from this Exhibit pursuant to Item 601(a)(5) of Regulation S-K. The Registrant will furnish a copy of any omitted schedule or exhibit to the U.S. Securities and Exchange Commission or its staff upon request.

@    Indicates management contract or compensatory plan

			X4 PHARMACEUTICALS, INC.
Date: March 21, 2023			By:						/s/ Paula Ragan
									Paula Ragan, Ph D.
									President and Chief Executive Officer

Signature

Title

Date

/s/ Paula Ragan

President, Chief Executive Officer and Director

March 21, 2023

Paula Ragan, Ph.D.

(Principal Executive Officer)

/s/ Adam S. Mostafa

Chief Financial Officer and Treasurer

March 21, 2023

Adam S. Mostafa

(Principal Financial Officer and Principal Accounting Officer)

/s/ Michael S. Wyzga

Chairman of the Board of Directors

March 21, 2023

Michael S. Wyzga

/s/ William Aliski

Director

March 21, 2023

William E. Aliski

/s/ Gary J. Bridger

Director

March 21, 2023

Gary J. Bridger, Ph.D.

/s/ Francoise De Craecker

Director

March 21, 2023

Francoise De Craecker

/s/ Alison Lawton

Director

March 21, 2023

Alison F. Lawton

/s/ David McGirr

Director

March 21, 2023

David McGirr

/s/ Murray W. Stewart

Director

March 21, 2023

Murray W. Stewart, M.D.

			Page
Report of Independent Registered Public Accounting Firm			F-2
Consolidated Balance Sheets			F-4
Consolidated Statements of Operations and Comprehensive Loss			F-5
Consolidated Statements of Redeemable Common Stock and Stockholders’ Equity			F-6
Consolidated Statements of Cash Flows			F-7
Notes to Consolidated Financial Statements			F-7

To the Board of Directors and Stockholders of X4 Pharmaceuticals, Inc.

/s/ PricewaterhouseCoopers LLP
Boston, Massachusetts
March 21, 2023
We have served as the Company’s auditor since 2016.

(In thousands, except share and per share amounts)

			December 31, 2022						December 31, 2021
Assets
Current assets:
Cash and cash equivalents			$	121,718					$	81,787
Research and development incentive receivable			1,152						747
Prepaid expenses and other current assets			5,807						5,344
Total current assets			128,677						87,878
Property and equipment, net			1,104						1,514
Goodwill			17,351						17,351
Right-of-use assets			7,229						8,710
Other assets			1,225						1,723
Total assets			$	155,586					$	117,176
Liabilities and Stockholders’ Equity
Current liabilities:
Accounts payable			$	7,777					$	4,283
Accrued expenses			12,034						7,870
Current portion of lease liability			1,198						1,075
Current portion of long-term debt			1,315						795
Total current liabilities			22,324						14,023
Long-term debt, including accretion, net of discount			32,304						33,139
Lease liabilities			3,603						4,776
Warrant liability (Note 4)			23,131						—
Other liabilities			173						826
Total liabilities			81,535						52,764
Commitments and contingencies (Note 9)
Stockholders’ equity:
Common stock, $0.001 par value. 500,000,000 and 125,000,000 shares authorized as of December 31, 2022 and December 31, 2021, respectively; 121,667,250 and 28,127,657 shares issued and outstanding as of December 31, 2022 and December 31, 2021, respectively			122						28
Additional paid-in capital			450,786						347,374
Accumulated other comprehensive loss			(119)						(119)
Accumulated deficit			(376,738)						(282,871)
Total stockholders’ equity			74,051						64,412
Total liabilities and stockholders’ equity			$	155,586					$	117,176
The accompanying notes are an integral part of these consolidated financial statements