Alto Neuroscience Strengthens Intellectual Property Portfolio with Issuance of New Method-of-Treatment Patent for ALTO-207 in Depression

– Issued and pending claims expected to protect ALTO-207 into the mid-2040s –

MOUNTAIN VIEW, Calif.–(BUSINESS WIRE)–$anro #cns–Alto Neuroscience, Inc. (“Alto”) (NYSE: ANRO), a clinical-stage biopharmaceutical company focused on the development of novel precision medicines for neuropsychiatric disorders, today announced the issuance of U.S. Patent Number 12,521,374 covering methods of treating depression with ALTO-207, a novel combination of pramipexole and ondansetron. The patent protects a key aspect of ALTO-207 – the use of ondansetron to mitigate pramipexole-related side effects so that patients can achieve the higher dose levels needed to realize the antidepressant benefits of pramipexole. The newly issued patent claims further strengthen the company’s growing intellectual property estate supporting ALTO-207, a differentiated investigational therapy being developed for patients with treatment-resistant depression.

The company believes that, together with previously issued patents and pending applications in the U.S. and internationally, the ALTO-207 intellectual property portfolio provides protection extending into the mid-2040s, reinforcing the long-term commercial opportunity for the program.

“This patent issuance meaningfully strengthens the foundation of our ALTO-207 franchise,” said Amit Etkin, M.D., Ph.D., founder and chief executive officer of Alto Neuroscience. “Robust and durable intellectual property is critical as we advance precision-based treatments for depression, and this milestone reflects both the novelty of ALTO-207 and our commitment to building long-term value for patients, clinicians, and shareholders. We believe the breadth and duration of our issued and pending claims position ALTO-207 as a potentially enduring asset in the treatment landscape for depression.”

The Company believes the issuance of this patent reinforces Alto’s strategy of building a portfolio of differentiated, innovative, precision-driven assets protected by robust intellectual property estates.

About ALTO-207

ALTO-207 is a fixed-dose combination of pramipexole, a dopamine D3-preferring D3/D2 agonist, approved for the treatment of Parkinson’s disease with demonstrated antidepressant effect, and ondansetron, an antiemetic, selective 5-HT3 receptor antagonist. As a fixed-dose combination, ALTO-207 is designed to enable rapid titration and higher dosing by mitigating the dose-limiting adverse events typically experienced with pramipexole. ALTO-207 is being developed to address the significant unmet need for patients with treatment resistant depression.

In a randomized, placebo-controlled Phase 2a clinical trial evaluating ALTO-207 in 32 patients with depression ALTO-207 met primary and secondary endpoints demonstrating significantly greater improvements on MADRS compared to placebo. Patients randomized to receive ALTO-207 reached a mean dose of 4.1mg per day. ALTO-207 was well tolerated in the maintenance period of the study with an adverse event rate similar to placebo.

About Alto Neuroscience

Alto Neuroscience is a clinical-stage biopharmaceutical company with a mission to redefine psychiatry by leveraging neurobiology to develop personalized and highly effective treatment options. Alto’s Precision Psychiatry Platform™ measures brain biomarkers by analyzing EEG activity, neurocognitive assessments, wearable data, and other factors to better identify which patients are more likely to respond to Alto product candidates. Alto’s clinical-stage pipeline includes novel drug candidates in bipolar depression, major depressive disorder, treatment resistant depression (TRD), and schizophrenia, and other mental health conditions.

Forward-Looking Statements

This press release may contain forward-looking statements made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. These statements may be identified by words such as “aims,” “anticipates,” “believes,” “could,” “estimates,” “expects,” “forecasts,” “goal,” “intends,” “look forward,” “may,” “plans,” “possible,” “potential,” “seeks,” “will” and variations of these words or similar expressions that are intended to identify forward-looking statements, although not all forward-looking statements contain these words. Forward-looking statements in this press release include, but are not limited to statements regarding Alto’s expectations about the potential benefits, activity, effectiveness, tolerability, and safety of its product candidates and Precision Psychiatry Platform (“Platform”); statements regarding Alto’s expectations for the design, timing, and results of its planned Phase 2b and Phase 3 trials of ALTO-207 in TRD; Alto’s expectations with regard to the general design and results of its research and development programs and clinical trials, Alto’s expectations regarding the protections afforded by its patent portfolio; and other statements that are not historical fact. Actual results or events could differ materially from the plans, intentions and expectations disclosed in these forward-looking statements as a result of various factors, including uncertainties inherent in the initiation, progress and completion of clinical trials and clinical development of Alto’s product candidates, and other important factors, any of which could cause Alto’s actual results to differ from those contained in the forward-looking statements, which are described in greater detail in the section titled “Risk Factors” in each of Alto’s Annual Report on Form 10-K for the fiscal year ended December 31, 2024 and Alto’s Quarterly Report on Form 10-Q for the fiscal quarter ended September 30, 2025 filed with the Securities and Exchange Commission (“SEC”) as well as in other filings Alto may make with the SEC in the future. Any forward-looking statements contained in this press release speak only as of the date hereof, and Alto expressly disclaims any obligation to update any forward-looking statements contained herein, whether because of any new information, future events, changed circumstances or otherwise, except as required by law.

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Contacts

Investor and Media Contact:
Nick Smith

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