BOSTON — Seaport Therapeutics reported a wider second-quarter loss as the clinical-stage biotechnology company increased spending on its neuropsychiatric drug programs following a $260 million initial public offering.
The company posted a net loss of $62.6 million for the quarter ended June 30, compared with a net loss of $15.1 million in the same period last year.
Research and development expenses rose to $24.6 million from $13.4 million, primarily because of increased clinical development spending for GlyphAllo and GlyphAgo.
General and administrative expenses increased to $41.2 million from $5.1 million. Seaport attributed the increase mainly to one-time, noncash stock-based compensation related to its IPO and additional equity grants.
Seaport had $427.3 million in cash, cash equivalents and investments as of June 30. The company expects the funds to support its operating plans into 2029.
“The second quarter of 2026 was marked by two major milestones for Seaport — positive results from our Phase 1 proof-of-concept trial of GlyphAgo and the successful completion of our IPO,” said Daphne Zohar, Co-Founder and Chief Executive Officer of Seaport Therapeutics.
Seaport is enrolling patients in the Phase 2b BUOY-1 trial of GlyphAllo in major depressive disorder. The global, randomized and placebo-controlled study is evaluating patients with or without anxious distress, with topline data expected in the first half of 2027.
The company is also conducting a Phase 1 trial assessing the effect of GlyphAllo on simulated driving performance in healthy volunteers. Topline results are expected in the second half of 2026.
GlyphAllo, also known as SPT-300, is Seaport’s lead drug candidate.
Seaport also plans to advance GlyphAgo, or SPT-320, into two Phase 2 studies for generalized anxiety disorder following positive Phase 1 results.
The company said GlyphAgo demonstrated a 6.8-fold increase in bioavailability compared with unmodified agomelatine and showed substantially lower pharmacokinetic variability.
In a multiple-ascending-dose portion of the study, seven days of treatment achieved therapeutic exposures at doses expected to reduce liver exposure and potentially eliminate the need for routine liver function monitoring.
Seaport said GlyphAgo was well tolerated across all tested doses, with no serious or severe adverse events, liver-related adverse events or clinically significant changes in liver laboratory measurements.
The company plans to begin a Phase 2a trial in patients with generalized anxiety disorder and sleep disturbance in the second half of 2026. Topline results are expected in early 2028.
A potentially registration-enabling Phase 2b trial in generalized anxiety disorder is expected to begin in the first half of 2027, with topline data anticipated by the end of 2028.
Seaport is also developing Glyph2BLSD, or SPT-348, a non-hallucinogenic neuroplastogen intended to reproduce some of the pharmacological effects of psychedelics without causing hallucinations.
The company expects to complete studies needed to support first-in-human testing of Glyph2BLSD by the end of 2027.
Seaport completed an upsized IPO in May that generated $260 million in gross proceeds. The company said the financing is expected to support several clinical data readouts across its GlyphAllo and GlyphAgo programs.
Sharon Mates, Ph.D., joined Seaport’s Board of Directors in April. She previously served as Co-Founder, Chairman and Chief Executive Officer of Intra-Cellular Therapies until its $14.6 billion acquisition by Johnson & Johnson in 2025.
