Sionna Therapeutics Inc. Common Stock (SION)

FairStock Score: 20/100 — RISKY

Key Financials

AI Analysis

AI-generated, general educational analysis — not personal investment advice.

I am a value investor who wants proven earning power and a margin of safety, so Sionna is not a typical candidate. It is a clinical-stage cystic fibrosis company with no revenue in any filed period. In fiscal 2025, the year ended 2025-12-31, it reported a net loss of $75.3 million, or diluted EPS of -$1.88, compared with a fiscal 2024 net loss of $61.7 million, or diluted EPS of -$15.99. The loss is widening, not narrowing: in fiscal Q2 2026, the quarter ended 2026-06-30, net loss was $29.9 million, or -$0.66 per diluted share, versus a fiscal Q2 2025 loss of $18.1 million, or -$0.41. Trailing free cash flow was -$76.2 million, a FairStock-calculated FCF yield of -38.5% against the $198.0 million market cap; that is heavy cash consumption. The balance sheet has low leverage, with D/E of 0.03, and FairStock's Altman Z-Score of 6.12 does not scream balance-sheet distress. But FairStock calculations show Piotroski at 0/9 and a FairStock Score of 20/100, so the fundamentals are weak. At the 2026-10-13 close of $4.38, FairStock's P/B is 0.74, suggesting the market values equity below book, while FairStock's P/E of -2.04 reflects no profits. The 52-week range of $4.01 to $54.97 shows how violently sentiment has swung. The moat is unproven: multiple CF candidates are in clinical testing, but there is no revenue and only clinical-stage candidates. Growth today is rising losses. Graham would call this speculation unless asset value and cash provide protection. I would watch cash burn, trial data, and financing needs.

In plain English: Sionna Therapeutics is a small clinical-stage biotechnology company with 59 employees working on experimental medicines for cystic fibrosis. It has no product revenue and is losing money; in fiscal 2025 it lost $75.3 million, and the losses are getting larger. At $4.38 on 2026-10-13, the stock looks cheap compared with the value of its accounting net assets, but the business itself is unprofitable and burning cash, so it is a high-risk situation rather than a proven bargain.

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Data as of 2026-10-13 close · note generated 2026-10-15 · model deepseek-flash

Sources (SEC EDGAR): fiscal Q2 2026 10-Q (period ended 2026-06-30) · fiscal Q1 2026 10-Q (period ended 2026-03-31) · fiscal Q3 2025 10-Q (period ended 2025-09-30) · fiscal Q2 2025 10-Q (period ended 2025-06-30) · FY2025 10-K (period ended 2025-12-31) · FY2024 10-K (period ended 2024-12-31)

Fundamentals from company filings and market-data providers; prices are end-of-day, not real-time. AI-generated analysis is general and educational — not personal investment advice. Scoring methodology · Score test · Disclaimer