Ardelyx (ARDX): RA Capital Management Boosts Stake to 7.7%

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Peter Kolchinsky‘s RA Capital Management has stepped up its interest in Ardelyx Inc. (NASDAQ:ARDX). As reported in a recent filing with the Securities and Exchange Commission, the fund now holds 3.46 million shares of the stock, plus warrants to acquire an additional 168,225 shares, giving it economic exposure to 7.7% of Ardelyx’s common stock. At the end of March, RA Capital reportedly held 2.3 million shares.

Founded in 2007, Ardelyx Inc. (NASDAQ:ARDX) engages in the research and development of minimally-systemic therapeutics for the treatment of gastrointestinal and cardio-renal diseases. Tenapanor, the company’s top candidate, is currently undergoing Phase 3 trials and has so far demonstrated efficiency in reducing the absorption of dietary sodium and phosphorus, which are key factors in some kidney diseases. The first results from the trials are expected in 2017. The recently agreed-upon takeover of Relypsa Inc (NASDAQ:RLYP) by Galenica has sparked speculation that Ardelyx might be next in line for a takeover, as Relypsa’s top drug, Veltassa, has properties similar to those of Ardelyx’s candidates.


At the end of the first quarter, approximately 17% of Ardelyx Inc. (NASDAQ:ARDX)’s common stock was held by nine of the funds tracked by Insider Monkey, up from seven long positions registered three months earlier. Bihua Chen‘s Cormorant Asset Management was also invested in this stock, having indicated ownership of 1.48 million shares of it in its latest 13F filing. James E. Flynn‘s Deerfield Management established a fresh position in the stock during the first quarter, having amassed 275,000 Ardelyx shares by the end of March.

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You can access the original SEC filing by clicking here.

Ownership Summary Table

Name Sole Voting Power Shared Voting Power Sole Dispositive Power Shared Dispositive Power Aggregate Amount Owned Power Percent of Class
RA Capital Management 0 3,625,943 0 3,625,943 3,625,943 7.7%
Peter Kolchinsky 0 3,625,943 0 3,625,943 3,625,943 7.7%
RA Capital Healthcare Fund 0 2,451,968 0 2,451,968 2,451,968 5.2%

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Page 1 of 7 – SEC Filing

Washington, D.C. 20549


Under the Securities Exchange Act of


(Amendment No. __)*


 (Name of Issuer)


Common Stock, par value $0.0001 per share

(Title of Class of Securities)



(CUSIP Number)


July 18, 2016

(Date of Event Which Requires Filing of
this Statement)

Check the appropriate box to designate the rule pursuant to
which this Schedule is filed:

¨ Rule 13d-1(b)
x Rule 13d-1(c)
¨ Rule 13d-1(d)

*The remainder of this cover page shall
be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for
any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page
shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”)
or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however,
see the Notes).

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