Privacy Policy

Last updated: December 16, 2022

X4 Pharmaceuticals, Inc. and its subsidiaries recognize the importance of protecting your privacy.

By using our Website, (the, “Website”), you agree to be bound by the terms and conditions of this privacy policy (the, “Policy”) and the Terms of Use. If you do not agree with the terms of this Policy or the Terms of Use, or other terms and conditions on the Website, then do not use the Website. Based upon your specific relationship(s) with X4 Pharmaceuticals, Inc., we may collect, use, or disclose Personal Information (defined below) in ways described in more detail in one or more other agreements that we have or may in the future execute with you (“Other Agreements”). To the extent the Other Agreement includes additional terms that are not covered by or are inconsistent with this Policy, the terms and conditions of the Other Agreement will supersede this Policy.

This Website is not directed at children and we do not knowingly collect Personal Information (as defined below) from children under the age of 13. If we learn that we have received Personal Information from a child under the age of 13, we will delete it. If you learn that your child has provided us with Personal Information without your consent, you may contact us as set forth below.


Personal Information

We collect and store Personal Information that you provide voluntarily when using the Website. Personal Information is defined as information that can identify you as a specific individual. You are responsible for providing accurate and complete information. For example, you might provide us the following information: information requests, responses and survey information, site registrations, or web portal registration information. Personal Information does not include anonymized aggregate or statistical information from which such identification cannot be reconstituted.

If you request one of our services, we may collect the following Personal Information: full name, home address, e-mail address, telephone number, employment history, and your answers to other similar background information questions, and how you specifically use the Website.

Other Information

When you visit any page on the Website, we use a program that monitors and evaluates the Website’s traffic. It automatically records every visitor’s host, domain name, pages visited, length of user session, browser type and/or IP address. We use this information to find out how many people visit the Website to determine the areas of greatest interest on the Website, and to make improvements to the Website.

When you visit and interact with the Website, X4 Pharmaceuticals, Inc., and third parties with whom X4 Pharmaceuticals, Inc., has contracted to provide services to us, may collect other Personal Information, for example, a catalog of the site pages you visit, or your IP address.


The Website may use cookies or other technologies to help us deliver content specific to your interests, to process your inquiries or requests, and/or to analyze your visiting patterns. If you want to disable the use of cookies or remove them at any time from your computer, you can disable or delete them using your browser (consult your browser’s help menu to learn how to delete cookies), however, you must enable cookies to access certain information on the Website. For example, we use Google Analytics for to analyze your visiting patterns. To provide this service, Google Analytics may collect certain information about you from your computer using cookies. You can learn more about Google Analytics and how it collects and processes data by visiting: You can opt-out of the use of Google Analytics here:


We may use your Personal Information to:

  • Complete any registration that you request online;
  • Publish your Personal Information on our Website if you consent or opt-in to us sharing it;
  • Improve the Website;
  • Improve our products and services, and identify, develop, and offer new or expanded products and services;
  • Personalize your experience on the Website, and customize the content and/or format of the pages you visit;
  • Share information with you, if you opt-in to receive updates from us;
  • Ask you to participate in brief surveys; and/or
  • Generate aggregate statistical studies and conduct research related to our products and services and the use of the Website.

Based upon your specific relationship(s) with X4 Pharmaceuticals, Inc., we may use your Personal Information in ways described in more detail in one or more Other Agreements.


We disclose your Personal Information to certain third parties with whom we have a direct or indirect business or contract relationship. When you request our services, we will provide your Personal Information to third parties with whom we arrange for those services to be provided. We may also disclose information to third parties that provide administrative or processing services for us, for example, printing or mailing.

We may also disclose Personal Information collected on the Website to professional advisors, such as lawyers, auditors, bankers, and insurers, where necessary in the course of the professional services that they render to us. We may also disclose your Personal Information to acquirers and other relevant participants in business transactions (or negotiations of or due diligence for such transactions) involving a corporate divestiture, merger, consolidation, acquisition, reorganization, sale or other disposition of all or any portion of the business or assets of, or equity interests in, X4 Pharmaceuticals, Inc. (including, in connection with a bankruptcy or similar proceedings).

We may also disclose Personal Information collected on the Website, in accordance with applicable law, to assert or defend our rights and property, to prevent harm to others, to collect a debt, or in response to legal processes such as subpoenas. We may also provide (or reserve the right to provide) Personal Information to credit reporting agencies and to cooperate with law enforcement authorities and other governmental authorities consistent with applicable laws.

If you have specifically consented to our doing so, we may also share your Personal Information with third parties in order that they may offer you information about their goods and services.


This Website may contain links to other third-party websites. X4 Pharmaceuticals, Inc., does not control the privacy policies or practices of these third-party sites. You should review those policies before providing any information. X4 Pharmaceuticals, Inc., is not responsible for the content or practices of any linked third-party sites, and we provide these links solely for the convenience and information of our visitors.


X4 Pharmaceuticals, Inc., has established safeguards designed to protect the Personal Information we collect. However, security risk is inherent in all internet and information technologies, and we cannot guarantee the security of your Personal Information.


X4 Pharmaceuticals, Inc., reserves the right to change this Policy to respond to new laws, regulations, technology, or for other business reasons. Please check the Website from time to time to review any such changes. If we make material changes to this Policy, we will notify you by updating the date of this Policy and posting it on the Website or other appropriate means. Any modifications to this Policy will be effective upon our posting the modified version (or as otherwise indicated at the time of posting). In all cases, using the Website following the posting of changes to this Policy shall constitute your acceptance of the revised Policy.


You agree that any claim, action or proceeding arising out of this Policy, or your use of the Website, shall be governed by and construed in accordance with the laws of the United States and the Commonwealth of Massachusetts, without regard to principles of conflict of laws. Any claim, action or proceeding related to this Policy will be resolved exclusively in the state or federal courts located in the Commonwealth of Massachusetts and you consent to the jurisdiction of those courts.


California law permits users who are California residents to request and obtain from us once a year, free of charge, a list of the third parties to whom we have disclosed their Personal Information (if any) for their direct marketing purposes in the prior calendar year, as well as the type of Personal Information disclosed to those parties. We reserve the right to require additional information to confirm your identity and California residency.


Opt-out of marketing communications. You may opt-out of marketing-related emails by following the opt-out or unsubscribe instructions at the bottom of the email, or by contacting us. Please note that if you choose to opt-out of marketing-related emails, you may continue to receive service-related and other non-marketing emails.

Do Not Track. Although our Website currently does not have a mechanism to recognize the various web browser Do Not Track signals, we do offer you choices to manage your preferences as described in the sections above. To learn more about browser tracking signals and Do Not Track please visit:


We are headquartered in the United States and we may use service providers that operate in other countries. Your Personal Information may be transferred to the United States or other locations where privacy laws may not be as protective as those in your state, province, or country.


If you have any questions or concerns about this Policy, you may contact us at 857-529-8300 or write to us in care of:
61 North Beacon Street, 4th Floor
Boston, MA 02134