RTW INVESTMENTS, LP

RTW Investments' Q1 2026 13F is a $10.05B (up from $9.98B, +0.5%) 88-position virtually 100% healthcare-and-biotech portfolio -- among the largest dedicated biotech hedge funds in the 13F universe. The book is dominated by a 20-name mega-core of double-digit-to-mid-single-digit biotech positions: Madrigal Pharmaceuticals (MDGL, $1.04B, 10.4%, 2.0M shares, -10.1% value) at #1; Insmed (INSM, $792M, 7.9%, 4.8M shares, -6.0%); Protagonist Therapeutics (PTGX, $533M, 5.3%, 5.1M shares -- re-established via new uppercase CUSIP after prior lower-case class was SOLD); PTC Therapeutics (PTCT, $528M, 5.3%, 7.7M shares, -10.3%); Argenx (ARGX, $518M, 5.2%, 709K shares, -8.5%); CG Oncology (CGON, $473M, 4.7%, 7.0M shares, +247% shares, +$389M from $83.5M); Celcuity (CELC, $347M, 3.5%, 3.0M shares, +452% shares, +$292M from $55M). The defining Q1 2026 trades: CG Oncology (+247% shares, the portfolio's largest absolute increase, +$389M to $473M) and Celcuity (+452% shares, +$292M to $347M) -- these two adds transformed mid-tier positions into top-10 holdings. Tango Therapeutics ($278M, NEW), Erasca ($261M, NEW), Intuitive Surgical ($101M, NEW via clean CUSIP after malformed prior CUSIP was SOLD), Hinge Health ($74M, NEW), Kodiak Sciences ($57M, NEW), Waystar ($39M, NEW), Arrowhead ($37M, NEW re-established), and Orchestra Bio ($35M, NEW) were all new opens. Nine sold: Protagonist prior class ($442M), Penumbra ($269M), Axsome Therapeutics ($162M), Insulet ($92M), Masimo ($89M), Stryker ($86M), Beta Bionics ($76M), malformed Intuitive prior ($57M), RAPT Therapeutics ($55M). AUM rose +0.5% from $9.98B to $10.05B. 17 increased, 6 decreased, 18 unchanged. The 75.50 whaleScore on $10.05B reflects AUM. The portfolio's identity is a concentrated long-only-and-special-situations biotech book focused on RNA-and-antisense (Stoke $183M, GH Research $83M), oncology (Madrigal, CG Oncology, Cogent, Tango, Apogee, Spyre, Castle, Rocket, Taysha, Arcellx, Kodiak, Verastem, Immunocore, Zai Lab), rare-disease-and-neurological (Insmed, PTC, Argenx, Ultragenyx, Karuna/CMPS, Compass), gastroenterology-and-liver (Celcuity), diagnostic-and-imaging (Radnet, iRhythm, Natera), and medical-devices (Intuitive Surgical, Repligen). The Q1 2026 delta is best read as: RTW executed a massive core-rotation-and-deployment in Q1 2026 -- dramatically increasing its two highest-conviction oncology names (CG Oncology +247% to $473M, Celcuity +452% to $347M), re-establishing Protagonist via a new share class at full $533M size, adding nine new opens across oncology-and-diagnostics (Tango $278M, Erasca $261M, Intuitive $101M, Hinge $74M, Kodiak $57M, Waystar $39M, Arrowhead $37M, Orchestra $35M), while exiting nine legacy positions (Protagonist-old-class $442M, Penumbra $269M, Axsome $162M, Insulet $92M, Masimo $89M, Stryker $86M, Beta Bionics $76M, malformed Intuitive $57M, RAPT $55M). The +0.5% AUM increase from $9.98B to $10.05B reflects appreciation on existing positions slightly outpacing deployments. The post-Q1 $10.05B book is more oncology-and-gastroenterology-heavy (CG Oncology, Celcuity, Tango, Cogent, Castle, Apogee all up meaningfully) and less diagnostic-and-device-heavy (Penumbra, Insulet, Masimo, Stryker, RAPT all gone) than Q4. RTW's 100-biotech-name AUM stands as one of the most sector-concentrated institutional portfolios in the 13F universe, and Q1 2026 was its most active quarter in recent memory.