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RTW Investments, LP 13F holdings, Q4 2025

Holdings as of December 31, 2025 · filings on SEC EDGAR · latest filing →

RTW Investments, LP disclosed 91 US equity positions worth $10.0bn in its Q4 2025 13F filing. The largest position was MDGL at 11.6% of the reported book, followed by INSM and PTCT. Against the Q3 2025 filing, it opened 7 new positions, added to 18 and reduced 10 among the top 50 holdings.

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What did RTW Investments, LP own in Q4 2025? Top 50 positions

#StockSectorWeightValueSharesΔ sharesvs Q3 2025
1 MDGL MADRIGAL PHARMACEUTICALS INC Healthcare 11.6%$1.2bn1,993,687 0% held
2 INSM INSMED INC Healthcare 8.4%$842.9m4,842,879 57% added
3 PTCT PTC THERAPEUTICS INC Healthcare 5.9%$588.4m7,746,415 0% held
4 ARGX ARGENX SE Healthcare 5.7%$566.4m673,497 0% held
5 PTGX PROTAGONIST THERAPEUTICS INC Healthcare 4.4%$441.9m5,059,053 -12% reduced
6 NTRA NATERA INC Healthcare 3.4%$343.6m1,500,000 -25% reduced
7 RDNT RADNET INC Healthcare 2.8%$281.0m3,938,500 40% added
8 TARS TARSUS PHARMACEUTICALS INC Healthcare 2.7%$273.1m3,335,320 5% added
9 COGT COGENT BIOSCIENCES INC Healthcare 2.7%$269.7m7,592,241 119% added
10 PEN PENUMBRA INC Healthcare 2.7%$269.4m866,499 0% held
11 IRTC IRHYTHM TECHNOLOGIES INC Healthcare 2.1%$209.7m1,181,990 – new
12 APGE APOGEE THERAPEUTICS INC Healthcare 2.1%$204.7m2,712,097 0% held
13 APLSUSD APELLIS PHARMACEUTICALS INC 1.9%$192.6m7,666,764 – new
14 ACAD ACADIA PHARMACEUTICALS INC Healthcare 1.9%$190.8m7,144,524 0% held
15 ESTA ESTABLISHMENT LABS HLDGS INC Healthcare 1.9%$188.7m2,588,831 0% held
16 STOK STOKE THERAPEUTICS INC Healthcare 1.8%$176.1m5,546,856 8% added
17 RGEN REPLIGEN CORP Healthcare 1.7%$174.3m1,064,000 – new
18 CYTK CYTOKINETICS INC Healthcare 1.7%$172.9m2,721,158 0% held
19 IMCR IMMUNOCORE HLDGS PLC Healthcare 1.7%$169.0m4,869,798 0% held
20 AXSM AXSOME THERAPEUTICS INC Healthcare 1.6%$162.2m888,001 -21% reduced
21 GH GUARDANT HEALTH INC Healthcare 1.5%$151.3m1,481,033 0% held
22 NBIX NEUROCRINE BIOSCIENCES INC Healthcare 1.5%$150.6m1,062,072 0% held
23 SYRE SPYRE THERAPEUTICS INC 1.4%$136.7m4,171,996 15% added
24 ZLAB ZAI LAB LTD Healthcare 1.2%$122.8m6,959,032 204% added
25 IMTX IMMATICS N.V Healthcare 1.2%$120.1m11,433,354 30% added
26 BLTE BELITE BIO INC Healthcare 1.1%$114.4m715,332 129% added
27 URGN UROGEN PHARMA LTD Healthcare 1.1%$106.4m4,543,895 0% held
28 XNCR XENCOR INC Healthcare 1.0%$103.8m6,777,461 9% added
29 PODD INSULET CORP Healthcare 0.9%$92.3m324,600 – new
30 TSHA TAYSHA GENE THERAPIES INC Healthcare 0.9%$90.2m16,398,297 -33% reduced
31 MASI* MASIMO CORP 0.9%$88.9m683,294 0% held
32 QURE UNIQURE NV 0.9%$88.8m3,711,462 -16% reduced
33 SYK STRYKER CORPORATION Healthcare 0.9%$86.1m245,000 -50% reduced
34 CGON CG ONCOLOGY INC Healthcare 0.8%$83.5m2,012,127 18% added
35 CSTL CASTLE BIOSCIENCES INC Healthcare 0.8%$82.3m2,115,237 – new
36 IMVT IMMUNOVANT INC Healthcare 0.8%$80.8m3,177,850 – new
37 BBNX BETA BIONICS INC Healthcare 0.8%$76.2m2,500,000 -24% reduced
38 GHRS GH RESEARCH PLC 0.8%$75.4m5,933,815 7% added
39 REPL REPLIMUNE GROUP INC Healthcare 0.7%$69.4m7,140,352 12% added
40 RARE ULTRAGENYX PHARMACEUTICAL IN Healthcare 0.7%$69.0m3,000,139 -8% reduced
41 CRNXGBP CRINETICS PHARMACEUTICALS IN 0.6%$62.9m1,351,326 55% added
42 ORKA ORUKA THERAPEUTICS INC Healthcare 0.6%$62.4m2,058,148 6% added
43 RCKT ROCKET PHARMACEUTICALS INC Healthcare 0.6%$62.1m17,687,772 0% held
44 CMPS COMPASS PATHWAYS PLC Healthcare 0.6%$60.4m8,757,390 1% added
45 ISRG INTUITIVE SURGICAL INC Healthcare 0.6%$57.3m101,228 -50% reduced
46 RAPT RAPT THERAPEUTICS INC 0.6%$55.5m1,637,165 11% added
47 CELC CELCUITY INC Healthcare 0.5%$54.9m550,160 – new
48 VSTM VERASTEM INC Healthcare 0.5%$50.8m6,576,306 21% added
49 ALKS ALKERMES PLC Healthcare 0.5%$46.8m1,672,356 0% held
50 CNTA CENTESSA PHARMACEUTICALS PLC 0.4%$44.8m1,790,837 -22% reduced

Weights are shares of the reported long US equity book (options excluded). Values are as filed, normalised to whole dollars. Share changes compare against the immediately preceding filing only.