Institutional Manager · CIK 0001493215
RTW INVESTMENTS, LP
NEW YORK, NY · File #028-16670
Latest AUM
$9.98B
Positions
91
Top-10 Concentration
53.4%
Filings
9
Portfolio Value Over Time
2024-03
2024-06
2024-09
2024-12
2025-03
2025-06
2025-09
2025-12
Biggest QoQ Changes
Ranked by conviction flow (share change × current price) so mark-to-market moves don't dominate. Price effect column shows how much of the $ change was just the stock moving.
| Action | Issuer | Ticker / CUSIP | Δ Shares | Flow ($) | Price Effect |
|---|---|---|---|---|---|
| EXITED | AVIDITY BIOSCIENCES INC | 05370A108 | -11,372,829 | -$495.5M | $0 |
| ADD | INSMED INC | INSM | +1,758,321 | +$306.0M | +$92.6M |
| EXITED | AKERO THERAPEUTICS INC | 00973Y108 | -5,477,561 | -$260.1M | $0 |
| NEW | IRHYTHM TECHNOLOGIES INC | IRTC | +1,181,990 | +$209.7M | $0 |
| NEW | APELLIS PHARMACEUTICALS INC | APLS | +7,666,764 | +$192.6M | $0 |
| EXITED | MERUS N V | N5749R100 | -2,025,277 | -$190.7M | $0 |
| NEW | REPLIGEN CORP | RGEN | +1,064,000 | +$174.3M | $0 |
| ADD | COGENT BIOSCIENCES INC | COGT | +4,124,755 | +$146.5M | +$73.4M |
| REDUCE | NATERA INC | NTRA | -500,000 | -$114.5M | +$136.2M |
| NEW | INSULET CORP | PODD | +324,600 | +$92.3M | $0 |
Sector Allocation
Filing History
- 13F HOLDINGS REPORTQ/E Dec 202591 pos · $9.98B
- 13F HOLDINGS REPORTQ/E Sep 202574 pos · $8.12B
- 13F HOLDINGS REPORTQ/E Jun 202573 pos · $7.02B
- 13F HOLDINGS REPORTQ/E Mar 202568 pos · $6.54B
- 13F HOLDINGS REPORTQ/E Dec 202472 pos · $6.61B
- 13F HOLDINGS REPORTQ/E Sep 202468 pos · $6.91B
- 13F HOLDINGS REPORTQ/E Jun 202468 pos · $6.46B
- 13F HOLDINGS REPORTQ/E Mar 202469 pos · $6.77B
- 13F HOLDINGS REPORTQ/E Dec 202367 pos · $4.74B
Top 20 Holdings — Dec 2025
| # | Issuer | Ticker | Shares | Value | % of Portfolio |
|---|---|---|---|---|---|
| 1 | MADRIGAL PHARMACEUTICALS INC | MDGL | 1,993,687 | $1.16B | 12.32% |
| 2 | INSMED INC | INSM | 4,842,879 | $842.9M | 8.94% |
| 3 | PTC THERAPEUTICS INC | PTCT | 7,746,415 | $588.4M | 6.24% |
| 4 | ARGENX SE | ARGX | 673,497 | $566.4M | 6.01% |
| 5 | PROTAGONIST THERAPEUTICS INC | PTGX | 5,059,053 | $441.9M | 4.69% |
| 6 | NATERA INC | NTRA | 1,500,000 | $343.6M | 3.65% |
| 7 | RADNET INC | RDNT | 3,938,500 | $281.0M | 2.98% |
| 8 | TARSUS PHARMACEUTICALS INC | TARS | 3,335,320 | $273.1M | 2.90% |
| 9 | COGENT BIOSCIENCES INC | COGT | 7,592,241 | $269.7M | 2.86% |
| 10 | PENUMBRA INC | PEN | 866,499 | $269.4M | 2.86% |
| 11 | IRHYTHM TECHNOLOGIES INC | IRTC | 1,181,990 | $209.7M | 2.23% |
| 12 | APOGEE THERAPEUTICS INC | APGE | 2,712,097 | $204.7M | 2.17% |
| 13 | APELLIS PHARMACEUTICALS INC | APLS | 7,666,764 | $192.6M | 2.04% |
| 14 | ACADIA PHARMACEUTICALS INC | ACAD | 7,144,524 | $190.8M | 2.02% |
| 15 | ESTABLISHMENT LABS HLDGS INC | ESTA | 2,588,831 | $188.7M | 2.00% |
| 16 | STOKE THERAPEUTICS INC | STOK | 5,546,856 | $176.1M | 1.87% |
| 17 | REPLIGEN CORP | RGEN | 1,064,000 | $174.3M | 1.85% |
| 18 | CYTOKINETICS INC | CYTK | 2,721,158 | $172.9M | 1.83% |
| 19 | IMMUNOCORE HLDGS PLC | IMCR | 4,869,798 | $169.0M | 1.79% |
| 20 | AXSOME THERAPEUTICS INC | AXSM | 888,001 | $162.2M | 1.72% |