APGE Apogee Therapeutics, Inc. - 8-K

Item
1.01

Entry
into a Material Definitive Agreement.

On March 24, 2026, Apogee Therapeutics, Inc. (the “Company”)
entered into an underwriting agreement (“Underwriting Agreement”) with Jefferies LLC, TD Securities (USA) LLC, Stifel, Nicolaus &
Company, Incorporated and Guggenheim Securities, LLC, as the representatives of the Underwriters named therein (the “Underwriters”),
to issue and sell 5,000,000 shares of the Company’s common stock at a public offering price of $70.00 per share (the “Offering”).
In addition, the Company has granted the Underwriters an option (the “Option”) for a period of 30 days to purchase up to
an additional 750,000 shares of its common stock at the public offering price, less the underwriting discounts and commissions, which
the underwriters exercised in full on March 25, 2026.

The net proceeds from the Offering, including proceeds from the exercise
in full of the Option by the Underwriters, are expected to be approximately $377.4 million, after deducting the Underwriters’
discounts and commissions and estimated offering expenses.

The securities described above were offered pursuant to a shelf registration
statement (File No. 333-281503), which became effective on August 12, 2024. A final prospectus supplement dated March 24,
2026 relating to and describing the terms of the Offering was filed with the U.S. Securities and Exchange Commission on March 25,
2026. The Offering is expected to close on March 26, 2026.

In the Underwriting Agreement, the Company agreed to indemnify the
Underwriters against certain liabilities, including liabilities under the Securities Act of 1933, as amended, or to contribute payments
that the underwriters may be required to make because of such liabilities.

A copy of the Underwriting Agreement is filed as Exhibit 1.1
and is incorporated herein by reference. The foregoing description of the Underwriting Agreement does not purport to be complete and
is qualified in its entirety by reference to such exhibit.

A copy of the opinion of Gibson, Dunn &
Crutcher LLP relating to the validity of the issuance and sale of the shares of the common stock in the Offering is filed herewith as
Exhibit 5.1.

Item
9.01

Financial
Statements and Exhibits.

(d)  Exhibits.

EXHIBIT INDEX

Exhibit

No.

Description

1.1

Underwriting
Agreement, dated as of March 24, 2026, by and among Apogee Therapeutics, Inc., Jefferies LLC, TD Securities (USA) LLC,
Stifel, Nicolaus & Company, Incorporated and Guggenheim Securities, LLC.

5.1

Opinion
of Gibson, Dunn & Crutcher LLP.

23.1

Consent
of Gibson, Dunn & Crutcher LLP (included in Exhibit 5.1)

104

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