Buy Rating Reaffirmed: ALTO-207 TRD Trial on Track
Research Report

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Disclosures for Stifel, Alto Neuroscience Inc., March 17, 2026

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Published March 17, 2026, Stifel analyst Paul Matteis maintained a Buy rating on Alto Neuroscience Inc. (ANRO:NYSE) with an unchanged price target of US$33.00, representing approximately 48% upside from the then-current share price of US$22.36, following an in-line fourth quarter 2025 earnings report.

The rating reflects continued confidence in the company's precision psychiatry pipeline, led by ALTO-207, and a newly announced financing that meaningfully extends the company's cash runway.

Recent Developments

Concurrent with the earnings release, Alto Neuroscience announced a roughly US$120 million PIPE financing. Combined with the US$177 million in cash on hand at year-end 2025, the company's estimated pro forma cash position stood at approximately US$275 million as of February 28, 2026.

The report notes this capital is intended to support ALTO-207 through its planned Phase 3 trial, which is expected to initiate in early 2027, and potentially through an NDA filing. Additionally, in January 2026, ANRO disclosed the issuance of a new method-of-treatment patent, with the company anticipating intellectual property protection extending into the mid-2040s.

Pipeline & Clinical Progress

ALTO-207 (pramipexole + ondansetron) remains the analyst's primary focus and what he considers the company's most compelling asset. The combination drug candidate targets treatment-resistant depression (TRD), and its Phase 2b trial is on track to initiate in the first half of 2026, with data expected in the second half of 2027. ANRO acquired the rights to the combination and associated intellectual property from Chase Therapeutics, which had already completed Phase 1 and Phase 2a studies in major depressive disorder (MDD), allowing ANRO — with FDA concurrence — to proceed directly into Phase 2b.

The placebo-controlled, adjunctive study is designed to enroll approximately 178 TRD patients randomized 1:1, measuring change from baseline on the MADRS scale at eight weeks. The analyst draws favorable comparisons to two-drug combinations that have already achieved commercial success in neuropsychiatry, specifically Auvelity and KarXT.

ALTO-300 (agomelatine), already approved in the European Union and Australia for MDD, is on track for Phase 2b data readout in mid-2026. The program uses an EEG biomarker signature to enrich the patient population for likely responders. A blinded, pre-specified interim analysis conducted in 2025 led to optimization of the analysis population and a modest increase in target enrollment; the study now targets 200 biomarker-positive patients.

ALTO-101, a brain-penetrant PDE4 inhibitor delivered via transdermal patch and being studied for cognitive impairment associated with schizophrenia (CIAS), is expected to report topline data around the end of the first quarter of 2026. The study's primary endpoint is theta-band intertrial coherence (ITC), an EEG biomarker believed to correlate with cognitive performance. The analyst characterizes this as a signal-seeking biomarker study with relatively modest expectations. Separately, ALTO-100's Phase 2b topline data in bipolar depression (BPD) are expected in the second half of 2026.

Financial Results

For full-year 2025, ANRO reported a GAAP EPS loss of US$(2.19),inlinewiththepriorStifelestimateofUS$(2.38), with no product revenue as expected for a clinical-stage company.

Total operating expenses for the year were US$66.4 million, comprising US$45.6 million in research and development and US$20.7 million in SG&A. Looking ahead, Stifel projects FY2026 operating expenses of US$89.0 million — US$62.0 million in R&D and US$27.0 million in SG&A — reflecting the anticipated ramp in clinical activity, with a projected FY2026 GAAP EPS loss of US$(2.08).

Valuation & Target Price Methodology

Stifel's US$33 target price is derived from a discounted cash flow analysis using an 11.5% discount rate and a 1% terminal growth rate. ALTO-300 revenues in MDD are risk-adjusted at 25%, while ALTO-207 is modeled at a 40% probability of success, reflecting prior pramipexole data and positive KOL feedback, tempered by the absence of ANRO-specific randomized Phase 2 data. Modest credit is also ascribed to ALTO-100 in BPD and ALTO-101 in schizophrenia.

Risks

The analyst highlights clinical, regulatory, and commercial risks inherent to an early-stage biotechnology investment. These include the possibility of pipeline failures, safety setbacks, inability to obtain FDA approval, competitive pressure, and insurer pushback.

The risk of additional dilutive equity offerings is also noted, though the recently completed PIPE is expected to fund operations through a potential NDA for ALTO-207.

Analyst Outlook

Stifel remains constructive on ANRO, viewing the stock as largely valued on the ALTO-207 program while characterizing the risk/reward on the remaining pipeline as upside-biased.

With the Phase 2b TRD trial for ALTO-207 set to begin in the first half of 2026, Phase 2b MDD data for ALTO-300 expected mid-year, and near-term CIAS data from ALTO-101 due by the end of Q1 2026, the analyst sees a series of meaningful catalysts ahead. At the time of publication, ANRO shares traded at US$22.36, implying approximately 48% potential return to the US$33 target price.