Octagon Capital Advisors LP holds a focused book of 29 stocks worth $903.6M as of Q1 2026 (disclosed May 15, 2026, a ~45-day 13F lag). This quarter they opened Definium Therapeutics Inc and trimmed Dianthus Therapeutics Inc. Their largest long position is Dianthus Therapeutics Inc at 18% of the equity book.
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curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://arkolith.com/api/v1/funds/1839435/holdings"
Use Arkolith to show Octagon Capital Advisors LP's latest holdings, largest changes, and filing provenance.
Top-heavy: focused book
Share of the disclosed book in its largest positions. A higher top-5 share means a more concentrated, higher-conviction portfolio.
96% mapped to company sectors
Direct operating-company sectors from our SIC-based security master. ETF/fund and unclassified holdings stay visible separately; this is not ETF look-through exposure.
Estimated $ traded · quarter-end prices, no cost basis
Bars show each stock's share of the portfolio. Click a row for its position history.
| # | Security | Value | Shares | % Port | Last move | History |
|---|---|---|---|---|---|---|
| 1 | Dianthus Therapeutics Inc COM | $163.4M | 1.95M | 18.1% | ▼−19% Reduced · −470K sh | |
| 2 | Cogent Biosciences Inc COM | $90.5M | 2.35M | 10.0% | —Held | |
| 3 | Abivax Sa SPONSORED ADS | $75.4M | 677.0K | 8.3% | ▼−10% Reduced · −79K sh | |
| 4 | Alumis Inc COM | $62.4M | 2.83M | 6.9% | ▲+12% Added · +300K sh | |
| 5 | Definium Therapeutics Inc COM SHS | $46.1M | 2.44M | 5.1% | ▲New New position | |
| 6 | Arrivent Biopharma Inc COM | $45.5M | 1.97M | 5.0% | —Held | |
| 7 | Taysha Gene Therapies Inc COM SHS | $39.6M | 8.86M | 4.4% | —Held | |
| 8 | Kymera Therapeutics Inc COM | $35.4M | 425.0K | 3.9% | ▼−21% Reduced · −110K sh | |
| 9 | Mirum Pharmaceuticals Inc COM | $31.3M | 338.9K | 3.5% | ▲New New position | |
| 10 | Bioage Labs Inc COM | $30.6M | 1.75M | 3.4% | ▲+9.4% Added · +150K sh | |
| 11 | Centessa Pharmaceuticals PLC SPONSORED ADS | $29.8M | 750.0K | 3.3% | —Held | |
| 12 | Kalvista Pharmaceuticals Inc COM | $29.2M | 1.45M | 3.2% | ▲+14% Added · +177K sh | |
| 13 | Xenon Pharmaceuticals Inc COM | $28.5M | 490.0K | 3.2% | ▲New New position | |
| 14 | Terns Pharmaceuticals Inc COM | $27.9M | 530.0K | 3.1% | ▲New New position | |
| 15 | Ocular Therapeutix Inc COM | $26.8M | 3.17M | 3.0% | ▲+21% Added · +543K sh | |
| 16 | Palisade Bio Inc COM | $18.0M | 10.28M | 2.0% | ▲+7.4% Added · +708K sh | |
| 17 | Trevi Therapeutics Inc COM | $17.7M | 1.49M | 2.0% | ▼−47% Reduced · −1.3M sh | |
| 18 | Disc Medicine Inc COM | $17.3M | 270.0K | 1.9% | ▲New New position | |
| 19 | Aktis Oncology Inc COM | $17.2M | 960.8K | 1.9% | ▲New New position | |
| 20 | Context Therapeutics Inc COM | $13.8M | 5.25M | 1.5% | ▲New New position | |
| 21 | Precision Biosciences Inc COM NEW | $12.3M | 2.24M | 1.4% | ▲+17% Added · +319K sh | |
| 22 | DBV Technologies S A SPONSORED ADS | $12.0M | 574.2K | 1.3% | —Held | |
| 23 | Unicycive Therapeutics Inc COM NEW | $6.6M | 1.00M | 0.7% | —Held | |
| 24 | Bridgebio Oncology Therapeut COM NEW | $6.4M | 719.0K | 0.7% | ▼−31% Reduced · −324K sh | |
| 25 | Lexeo Therapeutics Inc COM | $6.3M | 1.10M | 0.7% | ▼−36% Reduced · −625K sh | |
| 26 | Pharvaris N V COM | $4.7M | 165.0K | 0.5% | ▼−75% Reduced · −506K sh | |
| 27 | Perspective Therapeutics Inc COM NEW | $3.3M | 791.6K | 0.4% | ▲New New position | |
| 28 | Evommune Inc COM SHS | $3.3M | 143.5K | 0.4% | ▼−71% Reduced · −357K sh | |
| 29 | Gossamer Bio Inc COM | $2.5M | 7.75M | 0.3% | ▼−44% Reduced · −6.2M sh |
As-of date vs the date the SEC received each filing
Holdings from SEC EDGAR 13F-HR filings, updated quarterly ~45 days after quarter-end. Public domain. The book and weighting are long equity only; disclosed put/call options are listed separately and excluded from those totals. Price-derived performance is withheld until the price-source policy and freshness gate are green.