Atossa Therapeutics (ATOS)
Develops oral (Z)-endoxifen for breast cancer and selected rare diseases.
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Develops oral (Z)-endoxifen for breast-cancer settings and selected rare-disease evaluation. A clinical-stage biopharmaceutical company, it has no approved candidate and remains dependent on clinical, regulatory, manufacturing, partner, intellectual-property, and financing activities.
Development centers on the company's oral (Z)-endoxifen program, a selective estrogen receptor modulator and degrader in Phase 2 clinical development for breast-cancer treatment and risk-reduction settings. The program is also being evaluated for selected rare diseases.
Operations are based in Seattle and have focused on therapeutics since the business moved away from its original breast-health diagnostics and device model. No product candidate is approved for any indication.
Progress and continued program development depend on clinical development, regulatory interactions, manufacturing and third-party relationships, intellectual property, and financing while the company operates at a loss.
Company facts
Target rangeAs of Sep 22, 2026
Latest analyst notes
| Date | Firm | Action | Prior | Current |
|---|---|---|---|---|
| Jul 7, 2026 | Rodman & Renshaw | Initiate | Rating: — | |
| Feb 12, 2026 | Craig-Hallum | Target | Target: — | Target: $10 |
EPSReportedEstimate
RevenueReportedEstimate
Balance sheet, Jun 30, 2026Cash & short-term investments $26.1M · Total debt $0 · Total assets $32.3M · Shareholders' equity $26.8M
- Revenue
- $0
- Operating income
- −$8.7M
- Net income
- −$8.5M
No dividends on record.
| Institutions | 14.94% | 1.49M shares | |
|---|---|---|---|
| 33 holders · as of Jun 30, 2026 | |||
| Insiders | 2.14% | 213.4K shares | |
| 8 holders · as of May 14, 2026 | |||
| Other | 82.92% | 8.28M shares | |
| remainder | |||
9.98M company shares as of Sep 23, 2026 · institutions as of Jun 30, 2026 · holders as of their latest filing
Top shareholders13F · 13D/G · Form 4
| Holder | Stake | Shares | Date |
|---|---|---|---|
Vanguard Capital Management LLCInstitution | 3.62% | 361,747 | as of Jun 30, 2026 |
Ameriprise Financial IncInstitution | 2.59% | 258,234 | as of Jun 30, 2026 |
BlackRock, Inc.Institution | 1.65% | 164,358 | as of Jun 30, 2026 |
Aster Capital Management (Difc) LtdInstitution | 1.45% | 144,853 | as of Jun 30, 2026 |
Renaissance Technologies LLCInstitution | 1.32% | 132,043 | as of Jun 30, 2026 |
Insider tradesForm 4
No open-market trades in the last 12 months.
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Compare
| Company | Price | Change | |||||
|---|---|---|---|---|---|---|---|
| Atossa Therapeutics | $2.23 | −1.33% | $22.5M | — | — | — | — |
| Olema Pharmaceuticals | $8.73 | −9.49% | $842.0M | — | — | — | — |
| Eli Lilly | $1,152.13 | −1.54% | $1.10T | 39.3 | 28.2 | 13.8 | +47.7% |
| Arvinas | $7.87 | −7.52% | $549.1M | 53.2 | — | 1.7 | +1,014.7% |
| AstraZeneca (ADR) | $163.75 | −2.74% | $261.12B | 25.3 | 15.4 | 4.3 | +6.4% |
| Novartis (ADR) | $142.63 | +0.95% | $268.53B | 21.3 | 15.2 | 4.8 | +0.9% |
| Median | 32.3 | 15.4 | 4.5 | +27.0% |