BOSTON–Seaport Therapeutics, Inc. (Nasdaq: SPTX), a clinical-stage biotechnology company developing treatments for neuropsychiatric disorders, reported a net loss of $26.4 million for the third quarter of 2026, compared with a loss of $22.5 million a year earlier, as the company increased spending on clinical development programs targeting depression and anxiety.
The company ended the quarter with $403.8 million in cash, cash equivalents and investments as of September 30, 2026. Seaport expects its existing financial resources to support operations into 2029, including through three anticipated mid-to-late-stage clinical trial data readouts.
Research and development expenses increased to $23.9 million during the quarter, up from $20.5 million in the corresponding period of 2025. The $3.4 million increase was primarily driven by clinical development costs associated with the company’s Phase 2b BUOY-1 trial of GlyphAllo, an experimental treatment for major depressive disorder (MDD).
General and administrative expenses rose to $6.5 million from $5 million a year earlier, reflecting higher costs associated with operating as a publicly traded company.
Alongside its financial results, Seaport reported progress across several clinical programs, including GlyphAllo and GlyphAgo, two experimental therapies being developed for psychiatric conditions.
“Over the last few months, Seaport met two key clinical milestones – we dosed the first patient in the Phase 2a proof-of-pharmacology trial of GlyphAgo in patients with GAD and sleep disturbance, and demonstrated that GlyphAllo did not impair next-morning driving performance in a Phase 1 driving trial,” said Daphne Zohar, Co-Founder and Chief Executive Officer at Seaport Therapeutics. “With GlyphAllo and GlyphAgo, Seaport is now advancing two Phase 2 programs, and we look forward to progressing these programs through a steady cadence of potential value-creating milestones. In this context, our team remains focused on the rigorous execution of the ongoing, potentially registration-enabling Phase 2b BUOY-1 trial of GlyphAllo in MDD. Enrollment in BUOY-1 is on track, with topline data expected in the first half of next year. As we approach the topline readout of BUOY-1, we also continue to explore potential indication expansion opportunities for the GlyphAllo program, including in generalized anxiety disorder.”
In September, Seaport announced positive topline results from a Phase 1 driving simulation trial evaluating GlyphAllo, also known as SPT-300, in healthy volunteers.
The randomized, double-blind, placebo-controlled study found that evening administration of 375 milligrams of GlyphAllo did not impair simulated driving performance the following morning compared with placebo after multiple days of dosing.
The study also found that a single evening dose of 250 milligrams did not impair next-morning simulated driving performance compared with placebo.
GlyphAllo was generally well tolerated, with no serious adverse events reported. Seaport plans to submit the findings to the U.S. Food and Drug Administration as part of its ongoing development program.
The company is continuing enrollment in its Phase 2b BUOY-1 trial, which is evaluating the safety and effectiveness of GlyphAllo in patients with major depressive disorder, including those experiencing anxious distress.
The global, randomized, double-blind, placebo-controlled trial is designed to potentially support future regulatory registration. Seaport expects to report topline results during the first half of 2027.
The company is also advancing GlyphAgo, or SPT-320, an experimental treatment for generalized anxiety disorder (GAD).
In October, Seaport administered the first dose to a patient in its Phase 2a trial evaluating GlyphAgo in people with generalized anxiety disorder and sleep disturbances.
The study is testing two daily doses of GlyphAgo, 16 milligrams and 32 milligrams, containing approximately 5 milligrams and 10 milligrams of agomelatine, respectively.
Researchers will assess changes in sleep quality using patient-reported measures, including the Insomnia Severity Index, along with electroencephalogram-based assessments of sleep patterns. Additional measurements include anxiety severity, overall illness severity, safety and drug exposure.
Topline results from the Phase 2a study are expected in early 2028.
Seaport also plans to initiate a larger Phase 2/3 clinical trial of GlyphAgo in patients with generalized anxiety disorder during the first half of 2027. The global study will evaluate the drug’s safety and effectiveness against placebo, with topline results expected by the end of 2028.
“In parallel, we are preparing to initiate the Phase 2/3, potentially registration-enabling trial of GlyphAgo in GAD in the first half of next year, and we expect topline data from both Phase 2 trials of GlyphAgo in 2028 – with data from the Phase 2a trial expected in early 2028, and data from the Phase 2/3 trial expected by year-end 2028,” Zohar said.
In October, Seaport presented additional Phase 1 pharmacokinetic findings for GlyphAgo at the 39th European College of Neuropsychopharmacology Congress.
The data showed that exposure to agomelatine increased with higher doses, with no significant food effect or accumulation over seven days of treatment.
According to the company, earlier Phase 1 findings demonstrated that GlyphAgo increased agomelatine bioavailability by 6.8 times and reduced variability in drug exposure by approximately 10 times compared with unmodified agomelatine.
Beyond its clinical-stage programs, Seaport is developing Glyph2BLSD, also known as SPT-348, an experimental non-hallucinogenic neuroplastogen intended for neuropsychiatric and headache disorders.
The compound is designed to produce certain pharmacological effects associated with psychedelic substances without causing hallucinations. Seaport expects to complete studies needed to support initial human testing by the end of 2027.
Seaport said its financial position should allow the company to continue developing its lead drug candidates through several major clinical milestones without requiring immediate additional financing.
“Seaport is well-capitalized, with cash runway through all three of our upcoming mid-to-late-stage clinical data readouts. There are a billion people living with mental illness – waiting and hoping for better medicines. We are committed to our mission to bring better days to patients and their families,” Zohar said.
