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style="font-size:1pt;font-weight:bold;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:9pt;margin:0pt 0pt 10pt 0pt;">Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:</p><a id="_ab477fbc_f0ba_46b3_834e_906b83eeb23e"></a><a id="Tc__vcsVSrOC0-yMOGOuayTkA_1_1"></a><a id="Tc_aiQcm9Fe1Um3cYBLbagffg_2_1"></a><a id="Tc_xTi9a85whUqgiLUomWhkYA_3_1"></a><a id="Tc_1FFcHP7-Y0qXb0kA_SVVEA_4_1"></a><table style="border-collapse:collapse;font-size:16pt;height:max-content;margin-left:auto;margin-right:auto;padding-left:0pt;padding-right:0pt;width:100%;"><tr style="height:1pt;"><td style="vertical-align:bottom;width:3.22%;margin:0pt;padding:0pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"></div></div></td><td style="vertical-align:bottom;width:96.77%;margin:0pt;padding:0pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="bottom:0pt;position:absolute;width:100%;"></div></div></td></tr><tr><td style="vertical-align:bottom;width:3.22%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 2pt 0pt;"><ix:nonNumeric format="ixt-sec:boolballotbox" contextRef="Duration_4_29_2021_To_4_29_2021_NQcrYvVg2kudRFgxlHmHyw" name="dei:WrittenCommunications" id="Tc_uI3afqfzdE-uKX37dJ4WpA_1_0"><span style="font-family:'Segoe UI Symbol';font-size:9pt;">&#9744;</span></ix:nonNumeric></p></td><td style="vertical-align:bottom;width:96.77%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:9pt;margin:0pt 0pt 2pt 0pt;">Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) </p></td></tr><tr><td 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style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="position:absolute;top:0pt;width:100%;"></div></div></td><td style="vertical-align:top;width:2.78%;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="position:absolute;top:0pt;width:100%;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:9pt;visibility:hidden;">&#8203;</span></p></div></div></td><td style="vertical-align:top;width:23.41%;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="position:absolute;top:0pt;width:100%;"></div></div></td><td style="vertical-align:top;width:2.88%;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="position:absolute;top:0pt;width:100%;"><p 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style="vertical-align:top;width:23.41%;border-bottom:1px solid #000000;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:9pt;text-align:center;margin:0pt 0pt 2.2pt 0pt;"><b style="font-weight:bold;">Trading Symbol(s)</b></p></td><td style="vertical-align:top;width:2.88%;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 2.2pt 0pt;"><span style="font-size:9pt;font-weight:bold;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:38.46%;border-bottom:1px solid #000000;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:9pt;text-align:center;margin:0pt 0pt 2.2pt 0pt;"><b style="font-weight:bold;">Name of each exchange on which registered</b></p></td></tr><tr><td style="vertical-align:top;width:32.45%;border-top:1px solid #000000;margin:0pt;padding:0pt 5.4pt 0pt 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id="Tc_mCujgeR0dkCJX5HszxqEjQ_2_2"><span style="font-size:9pt;">ARDX</span></ix:nonNumeric></p></td><td style="vertical-align:top;width:2.88%;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 2.2pt 0pt;"><span style="font-size:9pt;visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:38.46%;border-top:1px solid #000000;margin:0pt;padding:0pt 5.4pt 0pt 5.4pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 2.2pt 0pt;"><ix:nonNumeric format="ixt-sec:exchnameen" contextRef="Duration_4_29_2021_To_4_29_2021_NQcrYvVg2kudRFgxlHmHyw" name="dei:SecurityExchangeName" id="Tc_T-ExFyYiaUyp_4WBhcsH7w_2_4"><span style="font-size:9pt;">The Nasdaq Global Market</span></ix:nonNumeric></p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:6pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:9pt;margin:0pt 0pt 8pt 0pt;">Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (&#167;230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (&#167;240.12b-2 of this chapter).</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 8pt 0pt;"><span style="font-size:9pt;">Emerging growth company&#160;&#160;</span><ix:nonNumeric format="ixt-sec:boolballotbox" contextRef="Duration_4_29_2021_To_4_29_2021_NQcrYvVg2kudRFgxlHmHyw" name="dei:EntityEmergingGrowthCompany" id="Narr_JFyVHITJAUy9gEfXqaUudQ"><span style="font-family:'Segoe UI Symbol';font-size:9pt;">&#9744;</span></ix:nonNumeric></p><p style="font-family:'Times New Roman','Times','serif';font-size:9pt;margin:0pt;">If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section&#160;13(a) of the Exchange Act.&#160;&#160;&#9744;</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:6pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;padding-top:1pt;border-bottom:3.0pt solid #000000;border-top:1.0pt solid #000000;margin:0pt;"><span style="font-size:1pt;visibility:hidden;">&#8203;</span></p><p style="display:none;line-height:0pt;margin:0pt;"><span style="font-family:'Times New Roman','Times','serif';font-size:0pt;visibility:hidden;">&#8203;</span></p><a id="_74d0ac46_4844_4b79_a959_0947dc1d0c3e"></a></div></div>
<div style="background-color:#000000;clear:both;height:2pt;page-break-after:always;width:79.3%;border:0;margin:30pt 10.35% 30pt 10.35%;"></div><div style="max-width:100%;padding-left:10.35%;padding-right:10.35%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 5pt 0pt;"><b style="font-weight:bold;">Item&#160;8.01&#8195;Other Events</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt 0pt 18pt 0pt;">On April 29, 2021, Ardelyx, Inc. (the &#8220;Company&#8221;) announced that, in connection with the ongoing review of the Company&#8217;s New Drug Application (NDA) for tenapanor for the control of serum phosphorus in chronic kidney disease (CKD) patients on dialysis, the U.S. Food and Drug Administration (FDA) made a recent information request that required the Company to submit additional analyses of its clinical data to help the agency better understand the clinical data in light of tenapanor&#8217;s novel mechanism of action as compared to approved therapies. In response, the Company submitted the requested analyses which constitute a major amendment to the NDA, resulting in an extension of the PDUFA date by three months to July 29, 2021. Tenapanor has a unique mechanism of action and acts locally in the gut to inhibit the sodium hydrogen exchanger 3, or NHE3. This results in the tightening of the epithelial cell junctions and reducing paracellular uptake of phosphate, the primary pathway of phosphate absorption.</p><a id="_59f43029_b5a8_4c47_8dec_9961f6088bf4"></a><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 6pt 0pt;"><b style="font-weight:bold;">Item&#160;9.01&#8195;Financial Statements and Exhibits.</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><b style="font-weight:bold;">(d) Exhibits.</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:11pt;visibility:hidden;">&#8203;</span></p><table style="border-collapse:collapse;font-size:16pt;height:max-content;margin-left:auto;margin-right:auto;padding-left:0pt;padding-right:0pt;width:100%;"><tr><td style="vertical-align:bottom;width:9.28%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;text-align:center;margin:0pt;">Exhibit<br />No.</p></td><td style="vertical-align:bottom;width:2.78%;border-bottom:1px solid transparent;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;margin:0pt;">&#160;&#160;</p></td><td style="vertical-align:bottom;width:87.93%;border-bottom:1px solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;margin:0pt;">Description</p></td></tr><tr style="height:4.8pt;"><td style="vertical-align:middle;width:9.28%;border-top:1px solid #000000;margin:0pt;padding:0pt;"></td><td colspan="2" style="vertical-align:middle;width:90.71%;margin:0pt;padding:0pt;"></td></tr><tr><td style="vertical-align:top;width:9.28%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">104</p></td><td style="vertical-align:bottom;width:2.78%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:87.93%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">Cover Page Interactive Data File (embedded within the Inline XBRL document).</p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:1pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:11pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:11pt;visibility:hidden;">&#8203;</span></p><a id="_f90fc737_3be8_4086_b594_018bd6304713"></a></div></div>
<div style="background-color:#000000;clear:both;height:2pt;page-break-after:always;width:79.3%;border:0;margin:30pt 10.35% 30pt 10.35%;"></div><div style="max-width:100%;padding-left:10.35%;padding-right:10.35%;position:relative;"><div style="clear:both;max-width:100%;position:relative;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 6pt 0pt;"><b style="font-weight:bold;">SIGNATURES</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:justify;margin:0pt;">Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.</p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><table style="border-collapse:collapse;font-size:16pt;height:max-content;margin-left:auto;margin-right:auto;padding-left:0pt;padding-right:0pt;table-layout:auto;width:100%;"><tr><td style="vertical-align:top;width:45.82%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">Date: April 30, 2021</p></td><td style="vertical-align:bottom;width:4.67%;margin:0pt;padding:0pt;"></td><td colspan="2" style="vertical-align:bottom;width:49.49%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">ARDELYX, INC.</p></td></tr><tr><td style="vertical-align:middle;width:45.82%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">&#160;</p></td><td style="vertical-align:middle;width:4.67%;margin:0pt;padding:0pt;"></td><td style="vertical-align:middle;width:3.82%;margin:0pt;padding:0pt;"></td><td style="vertical-align:middle;width:45.67%;margin:0pt;padding:0pt;"></td></tr><tr><td style="vertical-align:top;width:45.82%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">&#160;</p></td><td style="vertical-align:bottom;width:4.67%;margin:0pt;padding:0pt;"></td><td style="vertical-align:bottom;width:3.82%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">By:</p></td><td style="vertical-align:bottom;width:45.67%;border-bottom:1.0pt solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 1pt 0pt;">/s/ Elizabeth Grammer</p></td></tr><tr><td style="vertical-align:top;width:45.82%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">&#160;</p></td><td style="vertical-align:bottom;width:4.67%;margin:0pt;padding:0pt;"></td><td style="vertical-align:bottom;width:3.82%;margin:0pt;padding:0pt;"></td><td style="vertical-align:bottom;width:45.67%;border-top:1.0pt solid #000000;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">Elizabeth Grammer</p></td></tr><tr><td style="vertical-align:top;width:45.82%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">&#160;</p></td><td style="vertical-align:bottom;width:4.67%;margin:0pt;padding:0pt;"></td><td style="vertical-align:bottom;width:3.82%;margin:0pt;padding:0pt;"></td><td style="vertical-align:bottom;width:45.67%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;">Chief Legal and Administrative Officer</p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:1pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="visibility:hidden;">&#8203;</span></p></div></div>
<div style="background-color:#000000;clear:both;height:2pt;margin-left:10.35%;margin-right:10.35%;margin-top:30pt;page-break-after:avoid;width:79.3%;border:0;"></div></body></html>
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​
​
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
​
FORM
8-K
​
CURRENT REPORT
Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934
Date of Report (Date of earliest event reported):
April 29, 2021
​
ARDELYX, INC.
(Exact name of registrant as specified in its charter)
​
Delaware
001-36485
26-1303944
(State or other jurisdiction
of incorporation)
(Commission
File Number)
(IRS Employer
Identification Number)
​
34175 ARDENWOOD BLVD.
,
FREMONT
,
CALIFORNIA
94555
400 FIFTH AVE.
,
SUITE 210
,
WALTHAM
,
Massachusetts
02451
(Address of principal executive offices, including Zip Code)
Registrant's telephone number, including area code: (
510
)
745-1700
​
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:
☐
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
☐
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
☐
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
​
Securities registered pursuant to Section 12(b) of the Act:
​
​
Title of each class
​
Trading Symbol(s)
​
Name of each exchange on which registered
Common Stock, par value $0.0001
​
ARDX
​
The Nasdaq Global Market
​
Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).
Emerging growth company
☐
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐
​
​
Item 8.01 Other Events
On April 29, 2021, Ardelyx, Inc. (the "Company") announced that, in connection with the ongoing review of the Company's New Drug Application (NDA) for tenapanor for the control of serum phosphorus in chronic kidney disease (CKD) patients on dialysis, the U.S. Food and Drug Administration (FDA) made a recent information request that required the Company to submit additional analyses of its clinical data to help the agency better understand the clinical data in light of tenapanor's novel mechanism of action as compared to approved therapies. In response, the Company submitted the requested analyses which constitute a major amendment to the NDA, resulting in an extension of the PDUFA date by three months to July 29, 2021. Tenapanor has a unique mechanism of action and acts locally in the gut to inhibit the sodium hydrogen exchanger 3, or NHE3. This results in the tightening of the epithelial cell junctions and reducing paracellular uptake of phosphate, the primary pathway of phosphate absorption.
Item 9.01 Financial Statements and Exhibits.
(d) Exhibits.
​
Exhibit
No.
Description
104
​
Cover Page Interactive Data File (embedded within the Inline XBRL document).
​
​
​
SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
​
Date: April 30, 2021
ARDELYX, INC.
By:
/s/ Elizabeth Grammer
Elizabeth Grammer
Chief Legal and Administrative Officer
​
​
​