AGREEMENT
EXHIBIT 1
Pursuant to Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, the undersigned hereby agree that only one statement containing the information required by Schedule 13D need be filed with respect to the ownership by each of the undersigned of shares of stock of X4 Pharmaceuticals, Inc.
EXECUTED this 29th day of October, 2025.
GROWTH EQUITY OPPORTUNITIES 18 VGE, LLC
| By: | NEA 18 VENTURE GROWTH EQUITY, L.P. Sole Member |
| By: | NEA PARTNERS 18 VGE, L.P. General Partner |
| By: | NEA 18 VGE GP, LLC General Partner |
By: *
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Managing Partner and Co-Chief Executive Officer
By: *
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Managing Partner and Co-Chief Executive Officer
NEA 18 VENTURE GROWTH EQUITY, L.P.
| By: | NEA PARTNERS 18 VGE, L.P. General Partner |
| By: | NEA 18 VGE GP, LLC General Partner |
By: *
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Managing Partner and Co-Chief Executive Officer
By: *
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Managing Partner and Co-Chief Executive Officer
NEA PARTNERS 18 VGE, L.P.
| By: | NEA
18 VGE GP, LLC General Partner |
By: *
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Managing Partner and Co-Chief Executive Officer
By: *
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Managing Partner and Co-Chief Executive Officer
NEA 18 VGE GP, LLC
By: *
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Managing Partner and Co-Chief Executive Officer
By: *
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Managing Partner and Co-Chief Executive Officer
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As attorney-in-fact
This Agreement relating to Schedule 13D was executed by ▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇ on behalf of the individuals listed above pursuant to a Power of Attorney, a copy of which is attached hereto as Exhibit 2.