UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): April 1, 2021

FUSION PHARMACEUTICALS INC.

(Exact name of registrant as specified in its charter)

270 Longwood Road South

Hamilton, Ontario, Canada, L8P 0A6

(Address of principal executive offices, including zip code)

(289) 799-0891

(Registrant’s telephone number, including area code)

Not Applicable

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

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

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

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.  ☐

Item 8.01 Other Event.

As previously disclosed, on March 1, 2021, Fusion Pharmaceuticals Inc. (the “Company” or “Fusion”) and Ipsen Pharma SAS (“Ipsen”) entered into an asset purchase agreement (the “Asset Purchase Agreement”) under which Fusion would acquire Ipsen’s intellectual property and assets related to IPN-1087, a small molecule targeting neurotensin receptor 1, or NTSR1, a protein expressed on multiple solid tumor types. Fusion completed the acquisition of IPN-1087 as contemplated under the Asset Purchase Agreement on April 1, 2021. IPN-1087 will henceforth be known as FPI-2059.

Under the Asset Purchase Agreement and a Share Purchase Agreement entered into by Fusion and Ipsen concurrently with the Asset Purchase Agreement, at the closing Fusion issued to Ipsen 600,000 shares of its common stock, representing the initial purchase price of 400,000 shares and an additional 200,000 shares issuable due to the achievement of a patent-related milestone which occurred prior to the closing, and paid €0.7 million in cash for existing inventory of IPN-1087. As previously disclosed, Fusion will also be obligated to pay Ipsen up to an additional €67.5 million upon the achievement of certain development and regulatory milestones; low single digit royalties on potential future net sales; and up to €350.0 million in net sales milestones, in each case, relating to products covered by the Asset Purchase Agreement.

The description of the Asset Purchase Agreement and the transactions contemplated thereby contained herein does not purport to be complete and is qualified in its entirety by reference to the complete text of the Asset Purchase Agreement, a copy of which was filed with the Securities and Exchange Commission as Exhibit 10.1 to the Company’s Current Report on Form 8-K filed on March 2, 2021 (File No. 001-39344) and is incorporated herein by reference.

Item 7.01 Regulation FD Disclosure.

On April 1, 2021, the Company issued a press release announcing the closing of transactions contemplated by the Asset Purchase Agreement. A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated by reference herein.

The information set forth in this Item 7.01 is “furnished” and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Exchange Act or the Securities Act of 1933, as amended, except as expressly set forth by specific reference in such a filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.