President — Nicholas C. Smith: The filing discloses the internal promotion of the CFO to President and CFO, accompanied by a significant retention package, rather than a departure.

of this Current Report (including Exhibit 99.1 attached hereto) is being furnished and shall not be deemed “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 it 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 filing.

Entry into a Material Definitive Agreement. On July 13, 2026, Alto Neuroscience, Inc. (the “ Company ”) entered into an underwriting agreement (the “ Underwriting Agreement ”) with BofA Securities, Inc., as representative of the several underwriters set forth therein (collectively, the “ Underwriters ”), to issue and sell 3,776,436 shares of common stock of the Company, par value $0.0001 per share (“ Common Stock ”), in an underwritten registered direct offering (the “ Offering ”) pursuant to…

Other Events. Cash, Cash Equivalents and Restricted Cash as of June 30, 2026 On July 13, 2026, Alto Neuroscience, Inc. (the “ Company ”) announced that, based upon preliminary estimates and information available to the Company, it estimates that its cash, cash equivalents and restricted cash were approximately $244.2 million as of June 30, 2026. This amount has not been audited, reviewed, or compiled by the Company’s independent registered public accounting firm. The Company’s actual cash, ca…

Results of Operations and Financial Condition. The information disclosed under the heading “Cash, Cash Equivalents and Restricted Cash as of June 30, 2026” under

Director — Andrew Miller, Ph.D.: Appointment of Andrew Miller, Ph.D. to the Board and NCGC.

of this Current Report on Form 8-K (including Exhibit 99.1 attached hereto) is being furnished and shall not be deemed “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 it 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 filing.

The filing pertains to equity plan amendments, not a management change.

of this Current Report on Form 8-K (including Exhibit 99.1 attached hereto) is being furnished and shall not be deemed “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 it 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 filing.

Entry Into A Material Definitive Agreement. Private Placement of Common Stock and Warrants On March 16, 2026, Alto Neuroscience, Inc. (the “ Company ”) entered into a Securities Purchase Agreement (the “ Purchase Agreement ”) with certain institutional investors (the “ Purchasers ”), pursuant to which the Company agreed to sell and issue to the Purchasers in a private placement transaction (the “ Private Placement ”) (i) 2,900,000 shares (the “ Shares ”) of the Company’s common stock, par val…

Unregistered Sales of Equity Securities. The disclosure regarding the securities to be sold and issued under the Purchase Agreement as set forth under

Other Events. On March 16, 2026, the Company issued a press release entitled “Alto Neuroscience Announces $120 Million Private Placement Financing.” The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

of this Current Report (including Exhibit 99.1 attached hereto) is being furnished and shall not be deemed “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 it 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 filing.

Unregistered Sales of Equity Securities. The disclosure regarding the securities to be sold and issued under the Purchase Agreement as set forth under

Entry Into A Material Definitive Agreement. Private Placement of Common Stock and Warrants On October 19, 2025, Alto Neuroscience, Inc. (the “ Company ”) entered into a Securities Purchase Agreement (the “ Purchase Agreement ”) with certain institutional and other accredited investors (the “ Purchasers ”), pursuant to which the Company agreed to sell and issue to the Purchasers in a private placement transaction (the “ Private Placement ”) (i) 3,832,263 shares (the “ Shares ”) of the Company’…

Other Events. On October 20, 2025, the Company issued a press release entitled “Alto Neuroscience Announces $50 Million Private Placement Financing.” The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference. The Company concurrently issued a press release entitled “Alto Neuroscience Announces Plans to Accelerate Development of ALTO-207 in Treatment Resistant Depression Following Successful Outcome from Recent FDA…

Termination of a Material Definitive Agreement. As previously disclosed, on February 3, 2025, the Company entered into a Sales Agreement (the “ Sales Agreement ”) with Leerink Partners LLC (the “ Agent ”), pursuant to which the Company from time to time may offer and sell shares of its common stock through or to the Agent having an aggregate offering price of up to $75 million. On October 20, 2025, the Company delivered written notice to the Agent to terminate the Sales Agreement, effective O…

of this Current Report (including Exhibit 99.1 attached hereto) is being furnished and shall not be deemed “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 it 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 filing.

Director — Raymond Sanchez, M.D.: Dr. Raymond Sanchez was appointed to the Board as an external hire.

The filing describes a repricing of underwater stock options for certain employees and executives.

Other Events. On June 3, 2025, Alto Neuroscience, Inc. issued a press release entitled “Alto Neuroscience Announces Acquisition of Novel Dopamine Agonist Combination Product Candidate, Adding Pivotal Trial Readout in Treatment Resistant Depression Within Current Cash Runway.” The full text of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

Entry Into A Material Definitive Agreement. On May 31, 2025 (the “Closing Date”), Alto Neuroscience, Inc. (the “Company”), and Chase Therapeutics Corporation (the “Seller”), entered into an Asset Purchase Agreement (the “Asset Purchase Agreement”) pursuant to which the Seller sold its rights, title, and interest in and to certain assets related to a novel combination of pramipexole and ondansetron, known as CTC-501, and a novel combination of pramipexole and aprepitant, known as CTC-413 (the…

The issuance of shares of the CTC Shares will be made in reliance upon the exemption from registration contained in Section 4(a)(2) of the Securities Act of 1933, as amended, and Rule 506 of Regulation D thereunder.

of this Current Report (including Exhibit 99.1 attached hereto) is being furnished and shall not be deemed “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 it 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 filing.

of this Current Report on Form 8-K (including Exhibit 99.1 attached hereto) is being furnished and shall not be deemed “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 it 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 filing.