RTW Investments PTCT Position
Active9-Fund ConvergenceRTW Investments held their position in PTC Therapeutics Inc. (PTCT) in Q4 2025, holding $588.4M worth of shares across 7,746,415 shares.
The position was first reported in Q1 2023 and has been tracked across 12 quarterly 13F filings.
PTCT is a convergence signal: 9 specialist biotech funds hold this stock, suggesting high institutional conviction.
There is an upcoming Phase 3 readout for PTC923 in 75 days (Jun 30, 2026), making the timing of RTW Investments's position particularly relevant.
Short interest stands at 12.2% of float with 7.2 days to cover, indicating significant bearish positioning against RTW Investments's long thesis.
About PTC Therapeutics Inc.
PTC Therapeutics, Inc., a biopharmaceutical company, focuses on the discovery, development, and commercialization of medicines to patients with rare disorders. Its portfolio pipeline includes commercial products and product candidates in various stages of development, including clinical, pre-clinical and research and discovery stages, focuses on the development of treatments for multiple therapeutic areas, such as rare diseases. The company offers Translarna and Emflaza for the treatment of Duchenne muscular dystrophy in the European Economic Area and the United States, as well as to treat nonsense mutation Duchenne muscular dystrophy in Brazil and Russia; commercializes Tegsedi and Waylivra for the treatment of rare diseases in Latin America and the Caribbean; and markets Evrysdi for the treatment of spinal muscular atrophy in adults and children two months and older in Brazil. The company's splicing platform includes PTC518, which is being developed for the treatment of Huntington's disease. PTC Therapeutics, Inc. has collaborations with F. Hoffman-La Roche Ltd and Hoffman-La Roche Inc., as well as the Spinal Muscular Atrophy Foundation to advance drug discovery and development research in regenerative medicine; and Akcea Therapeutics, Inc. to commercialize Tegsedi and Waylivra for the treatment of rare diseases in Latin America and the Caribbean. PTC Therapeutics, Inc. was incorporated in 1998 and is headquartered in South Plainfield, New Jersey.
Full company profile →Short Interest
12.2%
7.2 days to cover
RTW Investments PTCT Position History
| Quarter | Action | Shares | Change | Value |
|---|---|---|---|---|
| Q4 2025 | Held | 7,746,415 | — | $588.4M |
| Q3 2025 | Held | 7,746,415 | — | $475.4M |
| Q2 2025 | Increased | 7,746,415 | +263,288 | $378.3M |
| Q1 2025 | Increased | 7,483,127 | +90,000 | $381.3M |
| Q4 2024 | Held | 7,393,127 | — | $333.7M |
| Q3 2024 | Held | 7,393,127 | — | $274.3M |
| Q2 2024 | Decreased | 7,393,127 | -30,843 | $226.1M |
| Q1 2024 | Held | 7,423,970 | — | $216.0M |
| Q4 2023 | Increased | 7,423,970 | +188,774 | $204.6M |
| Q3 2023 | Held | 7,235,196 | — | $162.1M |
| Q2 2023 | Increased | 7,235,196 | +141,898 | $294.3M |
| Q1 2023 | New | 7,093,298 | +7,093,298 | $343.6M |
Frequently Asked Questions
Does RTW Investments own PTCT?
Yes. As of Q4 2025, RTW Investments holds 7,746,415 shares of PTC Therapeutics Inc. (PTCT) valued at $588.4M. This data comes from their SEC 13F filing.
How many hedge funds own PTCT?
9 specialist biotech hedge funds currently hold PTCT, including Tang Capital Management, Driehaus Capital, Avoro Capital Advisors and 5 more. When 3 or more specialist funds hold the same stock, BiotechEdge flags it as a convergence signal.
When did RTW Investments first buy PTCT?
RTW Investments's position in PTCT was first reported in Q1 2023. 13F filings are reported with a 45-day delay, so the actual purchase may have occurred earlier in the quarter.
Is RTW Investments's PTCT position increasing or decreasing?
RTW Investments held their PTCT position unchanged in the most recent quarter.
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