Rock Springs Capital ARDX Position
Active4-Fund ConvergenceRock Springs Capital increased their position in Ardelyx Inc. (ARDX) in Q4 2025, holding $13.4M worth of shares across 2,299,473 shares.
The position was first reported in Q4 2024 and has been tracked across 5 quarterly 13F filings.
ARDX is a convergence signal: 4 specialist biotech funds hold this stock, suggesting high institutional conviction.
There is an upcoming Phase 3 readout for Tenapanor 50 MG in 46 days (Jun 1, 2026), making the timing of Rock Springs's position particularly relevant.
About Ardelyx Inc.
Ardelyx, Inc., a biopharmaceutical company, discovers, develops, and commercializes medicines to treat gastrointestinal and cardiorenal therapeutic areas in the United States and internationally. The company's lead product candidate is tenapanor, which has completed Phase III clinical trial for the treatment of patients with irritable bowel syndrome with constipation, as well as in Phase III clinical trial to control serum phosphorus in adult patients with chronic kidney disease (CKD)on dialysis, or hyperphosphatemia. It is also developing RDX013, a potassium secretagogue, for the treatment of elevated serum potassium, or hyperkalemia, a problem among certain patients with kidney and/or heart disease; and RDX020, an early-stage program in metabolic acidosis, a serious electrolyte disorder in patients with CKD. The company has agreements with Kyowa Kirin in Japan, Fosun Pharmaceutical Industrial Development Co. Ltd. in China, and Knight Therapeutics, Inc. in Canada for the development and commercialization of tenapanor in their respective territories. The company was formerly known as Nteryx, Inc. and changed its name to Ardelyx, Inc. in June 2008. Ardelyx, Inc. was incorporated in 2007 and is headquartered in Waltham, Massachusetts.
Full company profile →Short Interest
10.0%
5.0 days to cover
Rock Springs Capital ARDX Position History
Frequently Asked Questions
Does Rock Springs Capital own ARDX?
Yes. As of Q4 2025, Rock Springs Capital holds 2,299,473 shares of Ardelyx Inc. (ARDX) valued at $13.4M. This data comes from their SEC 13F filing.
How many hedge funds own ARDX?
4 specialist biotech hedge funds currently hold ARDX, including Eventide Asset Management, Redmile Group, Deerfield Management. When 3 or more specialist funds hold the same stock, BiotechEdge flags it as a convergence signal.
When did Rock Springs Capital first buy ARDX?
Rock Springs Capital's position in ARDX was first reported in Q4 2024. 13F filings are reported with a 45-day delay, so the actual purchase may have occurred earlier in the quarter.
Is Rock Springs Capital's ARDX position increasing or decreasing?
Rock Springs Capital increased their ARDX position in the most recent quarter, adding 13,200 shares.
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