Seaport Therapeutics set terms this week for a $201 million initial public offering, pricing shares to fund clinical development of two neuropsychiatric candidates targeting depression and rare clotting disorders. The Boston-based company plans to deploy proceeds toward Phase 2 data readouts expected through late 2026.

The company is offering 11.2 million shares at a range of $17 to $19 per share. Renaissance Capital and SEC filings show the midpoint valuation at approximately $680 million post-money, assuming full exercise of the underwriter option. Lead underwriters Goldman Sachs and Jefferies structured the deal with a standard 15% greenshoe. Trading is expected to commence on Nasdaq under ticker SPTX by end of week, subject to market conditions.

Seaport's pipeline centers on two assets. The lead candidate, SPN-830, is a proprietary formulation targeting treatment-resistant depression. The company completed a Phase 1b study in Q4 2024 showing measurable CNS penetration with a differentiated pharmacokinetic profile. Phase 2a enrollment is underway with topline data expected Q3 2025. The second asset, SPN-604, addresses a rare clotting disorder affecting fewer than 20,000 US patients annually. Seaport licensed the compound from a European biotech in 2023 and plans to initiate a Phase 2 study in Q2 2025. The IPO proceeds are earmarked to fund both programs through key clinical milestones, with approximately $120 million allocated to SPN-830 and $60 million to SPN-604. The remainder covers manufacturing scale-up and general corporate purposes.

The timing reflects a modest thaw in biotech IPO markets. Year-to-date, 14 biotech companies have priced US offerings, raising a combined $1.8 billion, compared to 9 deals totaling $950 million in the same period last year. Neuropsychiatry remains an allocator favorite despite high failure rates. Three depression-focused biotechs went public in 2024, with mixed post-IPO performance. The median one-year return for that cohort sits at negative 22%, but the top performer trades 68% above its IPO price, reflecting binary bet appetite among crossover funds. Seaport's relatively modest valuation and dual-asset structure may appeal to funds seeking sector exposure with built-in diversification.

Allocators should track two near-term catalysts. First, the Phase 2a data readout for SPN-830 in Q3 2025 will determine whether the compound shows statistically significant improvement over placebo on standard depression scales. Second, the Phase 2 initiation for SPN-604 in Q2 2025 will provide clarity on the company's ability to execute dual-track development with IPO capital. Lock-up expirations typically occur 180 days post-pricing, placing potential insider selling around late Q3 2025, coinciding with the SPN-830 data release.

The $201 million raise positions Seaport with approximately 24 months of runway at current burn rates, sufficient to reach both Phase 2 readouts without a follow-on financing if enrollment proceeds on schedule.