Deerfield Management CPRX Position
ActiveDeerfield Management trimmed their position in Catalyst Pharmaceuticals Inc. (CPRX) in Q4 2025, holding $114.6M worth of shares across 4,911,161 shares.
The position was first reported in Q1 2023 and has been tracked across 12 quarterly 13F filings.
1 other tracked fund also holds CPRX.
Short interest stands at 10.2% of float with 7.8 days to cover, indicating significant bearish positioning against Deerfield's long thesis.
About Catalyst Pharmaceuticals Inc.
Catalyst Pharmaceuticals, Inc., a commercial-stage biopharmaceutical company, focuses on developing and commercializing therapies for people with rare debilitating, chronic neuromuscular, and neurological diseases in the United States. It offers Firdapse, an amifampridine phosphate tablets for the treatment of patients with lambert-eaton myasthenic syndrome (LEMS); and Ruzurgi for the treatment of pediatric LEMS patients. The company also develops Firdapse for the treatment of MuSK antibody positive myasthenia gravis, and spinal muscular atrophy type 3, as well as to treat hereditary neuropathy with liability to pressure palsies. It has license agreements with BioMarin Pharmaceutical Inc.; and collaboration and license agreement with Endo Ventures Limited for the development and commercialization of generic Sabril tablets. The company was formerly known as Catalyst Pharmaceutical Partners, Inc. and changed its name to Catalyst Pharmaceuticals, Inc. in May 2015. Catalyst Pharmaceuticals, Inc. was founded in 2002 and is based in Coral Gables, Florida.
Full company profile →Short Interest
10.2%
7.8 days to cover
Deerfield Management CPRX Position History
| Quarter | Action | Shares | Change | Value |
|---|---|---|---|---|
| Q4 2025 | Decreased | 4,911,161 | -63,606 | $114.6M |
| Q3 2025 | Increased | 4,974,767 | +2,095,291 | $98.0M |
| Q2 2025 | Decreased | 2,879,476 | -542,673 | $62.5M |
| Q1 2025 | Increased | 3,422,149 | +289,138 | $83.0M |
| Q4 2024 | Decreased | 3,133,011 | -3,096,623 | $65.4M |
| Q3 2024 | Decreased | 6,229,634 | -2,897,671 | $123.8M |
| Q2 2024 | Decreased | 9,127,305 | -3,512 | $141.4M |
| Q1 2024 | Increased | 9,130,817 | +241,916 | $145.5M |
| Q4 2023 | Increased | 8,888,901 | +696,901 | $149.4M |
| Q3 2023 | Held | 8,192,000 | — | $95.8M |
| Q2 2023 | Decreased | 8,192,000 | -2,163,099 | $110.1M |
| Q1 2023 | New | 10,355,099 | +10,355,099 | $171.7M |
Frequently Asked Questions
Does Deerfield Management own CPRX?
Yes. As of Q4 2025, Deerfield Management holds 4,911,161 shares of Catalyst Pharmaceuticals Inc. (CPRX) valued at $114.6M. This data comes from their SEC 13F filing.
How many hedge funds own CPRX?
2 specialist biotech hedge funds currently hold CPRX, including OrbiMed Advisors. When 3 or more specialist funds hold the same stock, BiotechEdge flags it as a convergence signal.
When did Deerfield Management first buy CPRX?
Deerfield Management's position in CPRX 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 Deerfield Management's CPRX position increasing or decreasing?
Deerfield Management trimmed their CPRX position in the most recent quarter, reducing by 63,606 shares.
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