Octagon Capital Advisors LP — 13F Holdings & Portfolio
CIK 1839435 · latest 13F-HR filed 2026-08-14
Octagon Capital Advisors LP manages $1.11B in 13F-reported U.S. long-equity assets across 27 reported positions as of its 2026-06-30 13F-HR filing. Its largest disclosed positions are DNTH (16.14%), DFTX (12.47%), ABVX (11.89%). Quarter over quarter (versus its 2026-03-31 filing) the fund opened 4 new positions, exited 7, added to 12, and trimmed 7.
AUM is the long-equity portion reported on Form 13F-HR. Excludes short positions, cash, foreign holdings, and non-13F assets. For informational purposes only — not investment advice.
21ST FLOOR
NEW YORK, NY 10065
$1.11B
Long-equity book
27
Distinct positions
2026-06-30
Filed 2026-08-14
+4 / −7 / ↑12 / ↓7
vs 2026-03-31
| Name | Title / Status | Ownership | Type |
|---|
Top Adds (vs prior quarter)
- DEFINIUM THERAPEUTICS INC$92.7M +200.9%
- ABIVAX SA$56.9M +75.5%
- TAYSHA GENE THERAPIES INC$26.4M +66.7%
- ARRIVENT BIOPHARMA INC$23.0M +50.6%
- ALUMIS INC$17.3M +27.7%
Top Trims
- CONTEXT THERAPEUTICS INC-$12.1M -87.7%
- TREVI THERAPEUTICS INC-$11.8M -66.8%
- OCULAR THERAPEUTIX INC-$6.4M -24.0%
- DBV TECHNOLOGIES S A-$2.6M -21.5%
- UNICYCIVE THERAPEUTICS INC-$1.9M -28.7%
New Positions
- SUMMIT THERAPEUTICS INC$18.2M
- ADLAI NORTYE LTD$10.7M
- FAETH THERAPEUTICS INC$9.0M
- GYRE THERAPEUTICS INC$6.3M
Exited Positions
- CENTESSA PHARMACEUTICALS PLC$29.8M
- KALVISTA PHARMACEUTICALS INC$29.2M
- TERNS PHARMACEUTICALS INC$27.9M
- BRIDGEBIO ONCOLOGY THERAPEUT$6.4M
- LEXEO THERAPEUTICS INC$6.3M
Rows tagged Call or Put are options positions, not stock. Per SEC Form 13F-HR, Value shows the notional value of the underlying (shares covered × underlying price), not the option premium. Shares is the number of underlying shares covered (divide by 100 for contract count).
| # | Issuer | Symbol | CUSIP | Value | Weight | Shares | Type |
|---|---|---|---|---|---|---|---|
| 1 | DIANTHUS THERAPEUTICS INC | DNTH | 252828108 | $179.5M | 16.14% | 1,841,667 | SH |
| 2 | DEFINIUM THERAPEUTICS INC | DFTX | 24477V105 | $138.8M | 12.47% | 2,950,000 | SH |
| 3 | ABIVAX SA | ABVX | 00370M103 | $132.3M | 11.89% | 993,000 | SH |
| 4 | COGENT BIOSCIENCES INC | COGT | 19240Q201 | $90.9M | 8.17% | 2,350,000 | SH |
| 5 | ALUMIS INC | ALMS | 022307102 | $79.7M | 7.16% | 2,830,700 | SH |
| 6 | ARRIVENT BIOPHARMA INC | AVBP | 04272N102 | $68.5M | 6.15% | 1,971,054 | SH |
| 7 | TAYSHA GENE THERAPIES INC | TSHA | 877619106 | $66.0M | 5.93% | 9,693,244 | SH |
| 8 | BIOAGE LABS INC | BIOA | 09077V100 | $42.8M | 3.85% | 1,748,000 | SH |
| 9 | MIRUM PHARMACEUTICALS INC | MIRM | 604749101 | $39.7M | 3.57% | 338,900 | SH |
| 10 | KYMERA THERAPEUTICS INC | KYMR | 501575104 | $35.5M | 3.20% | 310,000 | SH |
| 11 | AKTIS ONCOLOGY INC | AKTS | 01021M104 | $31.0M | 2.78% | 960,847 | SH |
| 12 | XENON PHARMACEUTICALS INC | XENE | 98420N105 | $29.6M | 2.66% | 490,000 | SH |
| 13 | ERASCA INC Call | ERAS | 29479A908 | $23.0M | 2.07% | 1,255,000 | SH |
| 14 | PALISADE BIO INC | PALI | 696389402 | $21.5M | 1.93% | 10,276,317 | SH |
| 15 | OCULAR THERAPEUTIX INC | OCUL | 67576A100 | $20.4M | 1.83% | 2,075,000 | SH |
| 16 | DISC MEDICINE INC | IRON | 254604101 | $19.7M | 1.78% | 270,000 | SH |
| 17 | SUMMIT THERAPEUTICS INC | SMMT | 86627T108 | $18.2M | 1.64% | 1,250,000 | SH |
| 18 | PHARVARIS N V | PHVS | N69605108 | $15.8M | 1.42% | 456,721 | SH |
| 19 | ADLAI NORTYE LTD | ANL | 00704R109 | $10.7M | 0.97% | 934,716 | SH |
| 20 | PRECISION BIOSCIENCES INC | DTIL | 74019P207 | $10.6M | 0.95% | 1,350,000 | SH |
| 21 | DBV TECHNOLOGIES S A | DBVT | 23306J309 | $9.4M | 0.85% | 574,200 | SH |
| 22 | FAETH THERAPEUTICS INC | FTH | 81728A207 | $9.0M | 0.81% | 361,010 | SH |
| 23 | GYRE THERAPEUTICS INC | GYRE | 403783103 | $6.3M | 0.57% | 954,416 | SH |
| 24 | TREVI THERAPEUTICS INC | TRVI | 89532M101 | $5.9M | 0.53% | 315,000 | SH |
| 25 | UNICYCIVE THERAPEUTICS INC | UNCY | 90466Y202 | $4.7M | 0.42% | 1,000,000 | SH |
| 26 | CONTEXT THERAPEUTICS INC | CNTX | 21077P108 | $1.7M | 0.15% | 3,050,000 | SH |
| 27 | GOSSAMER BIO INC | GOSS | 38341P102 | $1.3M | 0.11% | 7,750,000 | SH |
| Period | Filed | AUM | Holdings | Accession |
|---|---|---|---|---|
| 2026-06-30 | 2026-08-14 | $1.11B | 27 | 0001839435-26-000004 |
| 2026-03-31 | 2026-05-15 | $903.6M | 29 | 0001839435-26-000003 |
| 2025-12-31 | 2026-02-17 | $823.7M | 27 | 0001839435-26-000002 |
| 2025-09-30 | 2025-11-14 | $659.8M | 27 | 0001839435-25-000010 |