Company Description
Alto Neuroscience Inc. (NYSE: ANRO) is a clinical-stage biopharmaceutical company in the healthcare sector focused on biotechnology and the development of precision medicines for neuropsychiatric disorders. According to the company, its mission is to redefine psychiatry by leveraging neurobiology to develop personalized and highly effective treatment options. Alto applies a data-driven approach to match patients with specific investigational therapies based on brain-based biomarkers.
The company’s work centers on its Precision Psychiatry Platform™, which measures brain biomarkers by analyzing electroencephalography (EEG) activity, neurocognitive assessments, wearable data, and other factors. By using these objective measures, Alto aims to better identify which patients are more likely to respond to its product candidates. This biomarker-driven strategy is intended to address biological heterogeneity in conditions such as depression and schizophrenia.
Business focus and therapeutic areas
Alto Neuroscience describes itself as a clinical-stage biopharmaceutical company with a pipeline of product candidates targeting multiple neuropsychiatric conditions. Its clinical-stage programs include novel drug candidates in bipolar depression, major depressive disorder (MDD), treatment-resistant depression (TRD), and schizophrenia, as well as other mental health conditions. The company states that it is focused on patients whose conditions are characterized and stratified using brain-based biomarkers.
Alto’s approach is reflected in several named product candidates mentioned in company disclosures and news releases, including ALTO-100, ALTO-101, ALTO-203, ALTO-300, and ALTO-207. These candidates are being evaluated in different indications within neuropsychiatry, with study designs that often incorporate EEG or cognitive measures as key endpoints or biomarkers.
Key clinical programs and mechanisms
ALTO-207 is described by Alto as 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 disclosed in Alto’s news releases, ALTO-207 is being developed for treatment-resistant depression (TRD). The fixed-dose combination is designed to enable rapid titration and higher dosing by mitigating dose-limiting adverse events typically associated with pramipexole, with the goal of allowing patients to reach doses associated with antidepressant benefit.
In a randomized, placebo-controlled Phase 2a clinical trial in patients with depression, Alto reports that ALTO-207 met primary and secondary endpoints, demonstrating significantly greater improvements on the Montgomery Åsberg Depression Rating Scale (MADRS) compared to placebo. The company also notes that patients receiving ALTO-207 reached a mean dose of 4.1 mg per day and that the regimen was well tolerated in the maintenance period, with an adverse event rate similar to placebo. Alto highlights ALTO-207 as a differentiated investigational therapy intended to address significant unmet need in TRD.
ALTO-101 is described as a novel small molecule phosphodiesterase-4 (PDE4) inhibitor being developed for the treatment of cognitive impairment associated with schizophrenia (CIAS). Alto states that ALTO-101 is a brain-penetrant PDE4 inhibitor formulated as a novel transdermal product designed to retain desired brain effects while avoiding tolerability challenges and adverse effects known to be associated with PDE4 inhibitors. The company reports that ALTO-101 has demonstrated pro-cognitive effects in healthy volunteers, including significant and clinically relevant effects on EEG measures and cognitive performance in a Phase 1 study.
Alto has disclosed that the U.S. Food and Drug Administration (FDA) granted Fast Track designation to ALTO-101 for the treatment of CIAS. The company notes that there are currently no approved treatments for CIAS, which it describes as a core and disabling feature of schizophrenia affecting memory, attention, processing speed, and executive function. ALTO-101 is being evaluated in a Phase 2 proof-of-concept (POC) trial in CIAS, with the primary outcome focused on theta-band EEG activity, specifically theta-band inter-trial coherence (theta ITC).
ALTO-100 is described as a first-in-class, oral small molecule believed by the company to work through enhancing neuroplasticity. Alto is developing ALTO-100 for the treatment of bipolar depression (BPD) in patients characterized by a cognitive biomarker. The company has reported ongoing enrollment in a randomized, double-blind, placebo-controlled Phase 2b trial in BPD, with patients evaluated over a six-week treatment period using MADRS change from baseline as the primary endpoint in a biomarker-defined population.
ALTO-300, also known as agomelatine, is described as an oral small molecule designed to act as a melatonin agonist and 5-HT2C antagonist. Alto reports that agomelatine is an approved antidepressant medication in Europe and Australia at certain doses, but not approved in the United States. The company is developing ALTO-300 at 25 mg as an adjunctive treatment for major depressive disorder (MDD) in the United States, in patients characterized by an EEG biomarker, and is conducting a Phase 2b randomized, double-blind, placebo-controlled trial.
ALTO-203 is described in Alto’s communications as an H3 inverse agonist. The company has reported pharmacodynamic data from an exploratory Phase 2 proof-of-concept study, indicating effects on sustained attention, EEG measures such as theta/beta ratio, and wakefulness, and suggesting potential utility in indications with excessive daytime sleepiness and/or deficits in sustained attention.
Biomarker-driven development and EEG research
A central feature of Alto Neuroscience’s strategy is the use of EEG biomarkers and other objective measures to guide drug development. The company reports that its Precision Psychiatry Platform™ integrates EEG activity, neurocognitive assessments, wearable data, and other factors to identify patient subgroups more likely to benefit from specific product candidates.
In schizophrenia and CIAS, Alto has highlighted work on theta-band inter-trial coherence (theta ITC) and event-related spectral perturbation (ERSP) as EEG markers. The company has reported independent prospective analyses in large cohorts of individuals with schizophrenia and healthy controls, showing that theta ITC and ERSP robustly differentiate patients from controls and are significantly correlated with processing speed. Alto states that these measures outperform more traditional EEG markers such as mismatch negativity and resting-state theta power in case-control separation and cognitive associations. Based on these findings, the company is using theta ITC as a primary outcome measure in its ongoing Phase 2 trial of ALTO-101 in CIAS.
Alto has also described the development and validation of an EEG biomarker capable of predicting treatment response across various interventions and independent data sets in depression. The company reports that analyses using this biomarker in randomized controlled trials resulted in enhanced treatment effect detection compared to analyses that did not account for individual differences, suggesting a potential role for EEG biomarkers in improving signal detection in studies of interventions in major depressive disorder.
Intellectual property and regulatory designations
Alto Neuroscience emphasizes the importance of intellectual property protection and regulatory designations in its disclosures. The company has announced the issuance of U.S. Patent Number 12,521,374 covering methods of treating depression with ALTO-207, a fixed-dose combination of pramipexole and ondansetron. Alto states that this patent protects the use of ondansetron to mitigate pramipexole-related side effects so that patients can achieve higher dose levels needed to realize antidepressant benefits. 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.
In addition, Alto has disclosed that the FDA granted Fast Track designation to ALTO-101 for the treatment of CIAS. The company notes that Fast Track is intended to facilitate development and expedite review of drugs that treat serious conditions and address unmet medical needs, and may allow for more frequent interactions with the FDA and potential eligibility for accelerated approval and priority review if criteria are met.
Capital markets and corporate profile
Alto Neuroscience’s common stock is listed on the New York Stock Exchange under the ticker symbol ANRO, as confirmed in its SEC filings. The company has described itself as an emerging growth company under applicable securities regulations. In its public filings, Alto has reported the use of private placement financings, including a securities purchase agreement with institutional and accredited investors for a private placement of common stock and pre-funded warrants, with anticipated gross proceeds of approximately $50 million before expenses. The company has also filed information on option repricing for certain employee and consultant stock options, and on inducement grants under NYSE rules for new employees.
Alto’s SEC filings and press releases indicate that it uses equity-based compensation, including stock options, as part of its compensation structure for employees, consultants, and non-employee directors. The company has also reported board composition changes and committee assignments, reflecting governance arrangements typical of publicly listed biotechnology companies.
Location and regulatory reporting
According to its SEC filings, Alto Neuroscience, Inc. is based in Mountain View, California. As a U.S. public company, it files periodic and current reports with the Securities and Exchange Commission, including Forms 8-K reporting material events such as financing transactions, clinical and corporate updates, and changes in governance or compensation arrangements. The company has indicated that it routinely uses its website’s investor section, including an events and presentations page, to provide access to webcasts and replays of investor conference appearances.
Role within biotechnology and neuropsychiatry
Within the biotechnology industry, Alto Neuroscience positions itself at the intersection of neuropsychiatry, biomarker-based drug development, and precision medicine. Its public communications emphasize the use of objective brain-based measures, such as EEG biomarkers and cognitive assessments, to address variability in treatment response and to design trials that may better detect drug effects. The company’s pipeline spans depressive disorders, bipolar depression, treatment-resistant depression, and schizophrenia-related cognitive impairment, all areas where Alto describes substantial unmet medical needs.
Alto participates in scientific and medical conferences, such as the American College of Neuropsychopharmacology (ACNP) annual meeting, where it presents data on EEG biomarkers, pharmacodynamic effects of its compounds, and analyses supporting its precision psychiatry platform. The company also participates in healthcare and biotech investor conferences, where members of management discuss its development programs and corporate strategy.