X4 Pharmaceuticals, Inc

We lease approximately 28,000 square feet of office space at 61 North Beacon Street, 4th Floor, Boston, Massachusetts, which serves as our corporate headquarters. The lease expires on November 30, 2026. The base monthly payment on the lease is approximately $91 thousand as of December 31, 2024, subject to specified annual increases of approximately 3% during the term of the lease and not including operating expenses, certain utilities, taxes and insurance for which we are responsible. We have the right to sublease the premises, subject to landlord consent and we have the right to renew the lease for an additional five years at the then-prevailing effective market rental rate.

We lease approximately 1,200 square meters of laboratory and office space in Vienna, Austria under a lease that will expire in March 2028, with a monthly payment of approximately $24 thousand.