Octagon Capital Advisors LP reported 25 positions worth $1.08B for the quarter ended Jun 30, 2026, up 32.3% on the prior quarter. It opened 3 new positions, added to 4, trimmed 6 and exited 4. Its largest holding is Dianthus Therapeutics, Inc. at 16.6% of the portfolio.
Reported 13F market value at each quarter end. A change mixes trading with price moves in the positions held.
Dollar value of shares bought and sold each quarter, at that quarter’s price. It counts trading only, not price changes.
How many positions were opened, added to, trimmed or closed each quarter.
Share of reported value in each sector at every quarter end.
| Holding | Change | Change % | Trade Value | Weight |
|---|---|---|---|---|
| ABVX Abivax S.A. | +316.0K | +46.7% | $42.11M | 12.25% |
| DFTX Definium Therapeutics, Inc. | +510.0K | +20.9% | $23.99M | 12.84% |
| SMMT Summit Therapeutics Inc. | +1.25M | – | $18.21M | 1.69% |
| ANL Adlai Nortye Group Ltd. | +934.7K | – | $10.75M | 0.995% |
| PHVS Pharvaris N.V. | +291.7K | +176.8% | $10.09M | 1.46% |
| GYRE Gyre Therapeutics, Inc. | +954.4K | – | $6.29M | 0.582% |
| TSHA Taysha Gene Therapies, Inc. | +833.3K | +9.4% | $5.67M | 6.11% |
| Holding | Change | Change % | Trade Value | Weight |
|---|---|---|---|---|
| TRVI Trevi Therapeutics, Inc. | -1.17M | -78.8% | $21.82M | 0.544% |
| KYMR Kymera Therapeutics, Inc. | -115.0K | -27.1% | $13.19M | 3.29% |
| OCUL Ocular Therapeutix, Inc | -1.09M | -34.5% | $10.72M | 1.89% |
| DNTH Dianthus Therapeutics, Inc. | -105.0K | -5.4% | $10.24M | 16.61% |
| DTIL Precision Biosciences Inc | -886.7K | -39.6% | $6.97M | 0.982% |
| BBOT BridgeBio Oncology Therapeutics, Inc. | -719.0K | -100.0% | $6.44M | Exited |
| LXEO Lexeo Therapeutics, Inc. | -1.10M | -100.0% | $6.31M | Exited |
| CATX Perspective Therapeutics, Inc. | -791.6K | -100.0% | $3.30M | Exited |
| EVMN Evommune, Inc. | -143.5K | -100.0% | $3.30M | Exited |
| CNTX Context Therapeutics Inc. | -2.20M | -41.9% | $1.22M | 0.156% |
| # | Activity | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| 1 | DNTH Dianthus Therapeutics, Inc. | Healthcare | 1.84M | $179.53M | 16.61% | -105.0K | -5.4% | Reduced | 3.29% |
| 2 | DFTX Definium Therapeutics, Inc. | Healthcare | 2.95M | $138.77M | 12.84% | +510.0K | +20.9% | Added | 2.2% |
| 3 | ABVX Abivax S.A. | Healthcare | 993.0K | $132.33M | 12.25% | +316.0K | +46.7% | Added | 1.43% |
| 4 | COGT Cogent Biosciences, Inc. | Healthcare | 2.35M | $90.95M | 8.42% | 0 | 0.0% | Unchanged | 1.37% |
| 5 | ALMS Alumis Inc. | Healthcare | 2.83M | $79.66M | 7.37% | 0 | 0.0% | Unchanged | 2.22% |
| 6 | AVBP ArriVent BioPharma, Inc. | Healthcare | 1.97M | $68.47M | 6.34% | 0 | 0.0% | Unchanged | 4.08% |
| 7 | TSHA Taysha Gene Therapies, Inc. | Healthcare | 9.69M | $66.01M | 6.11% | +833.3K | +9.4% | Added | 2.63% |
| 8 | BIOA BioAge Labs, Inc. | Healthcare | 1.75M | $42.84M | 3.97% | 0 | 0.0% | Unchanged | 3.82% |
| 9 | MIRM Mirum Pharmaceuticals, Inc. | Healthcare | 338.9K | $39.68M | 3.67% | 0 | 0.0% | Unchanged | 0.52% |
| 10 | KYMR Kymera Therapeutics, Inc. | Healthcare | 310.0K | $35.55M | 3.29% | -115.0K | -27.1% | Reduced | 0.32% |
| 11 | AKTS Aktis Oncology, Inc. | Healthcare | 960.8K | $30.97M | 2.87% | 0 | 0.0% | Unchanged | 1.74% |
| 12 | XENE Xenon Pharmaceuticals Inc. | Healthcare | 490.0K | $29.58M | 2.74% | 0 | 0.0% | Unchanged | 0.49% |
| 13 | PALI Palisade Bio, Inc. | Healthcare | 10.28M | $21.48M | 1.99% | 0 | 0.0% | Unchanged | 4.86% |
| 14 | OCUL Ocular Therapeutix, Inc | Healthcare | 2.08M | $20.38M | 1.89% | -1.09M | -34.5% | Reduced | 0.92% |
| 15 | IRON Disc Medicine, Inc. | Healthcare | 270.0K | $19.75M | 1.83% | 0 | 0.0% | Unchanged | 0.7% |
Tip. Select a row to see that position’s full history at Octagon Capital Advisors.
As of its Q2 2026 13F filing, Octagon Capital Advisors LP’s five largest positions were Dianthus Therapeutics, Inc. (DNTH) at 16.6%, Definium Therapeutics, Inc. (DFTX) at 12.8%, Abivax S.A. (ABVX) at 12.2%, Cogent Biosciences, Inc. (COGT) at 8.4%, Alumis Inc. (ALMS) at 7.4% of the reported portfolio.
Octagon Capital Advisors LP reported a 13F portfolio worth $1.08B across 25 positions for Q2 2026. That is up 32.3% from the previous quarter.
Its largest purchases by value were Abivax S.A. ($42.11M), Definium Therapeutics, Inc. ($23.99M), Summit Therapeutics Inc. ($18.21M). It opened 3 new positions.
Its largest sales by value were Trevi Therapeutics, Inc. ($21.82M), Kymera Therapeutics, Inc. ($13.19M), Ocular Therapeutix, Inc ($10.72M). It exited 4 positions entirely.
From the Form 13F-HR reports Octagon Capital Advisors LP files with the SEC each quarter, within 45 days of quarter end. A 13F lists long positions in US-listed equities and options; it excludes short positions, cash, bonds and most non-US holdings.
13F data reflects long positions in US-listed equities and options as reported to the SEC up to 45 days after quarter end. It excludes short positions, cash, bonds and most non-US securities, so it is not a complete picture of a manager’s assets.