<?xml version='1.0' encoding='UTF-8'?>

      <!-- iXBRL document created with: Toppan Merrill Bridge iXBRL 9.6.7556.35618 -->
      <!-- Based on: iXBRL 1.1 -->
      <!-- Created on: 11/12/2020 10:15:39 PM -->
      <!-- iXBRL Library version: 1.0.7556.35625 -->
      <!-- iXBRL Service Job ID: 1ad07e09-e4b7-41ec-8fbc-3eb901546945 -->

  <html xmlns:dei="http://xbrl.sec.gov/dei/2019-01-31" xmlns="http://www.w3.org/1999/xhtml" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ardx="http://www.deitaxonomy.com/20201112" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xs="http://www.w3.org/2001/XMLSchema-instance" xmlns:ixt-sec="http://www.sec.gov/inlineXBRL/transformation/2015-08-31" xmlns:ixt="http://www.xbrl.org/inlineXBRL/transformation/2015-02-26" xmlns:ix="http://www.xbrl.org/2013/inlineXBRL" xmlns:ref="http://www.xbrl.org/2006/ref" xmlns:xbrli="http://www.xbrl.org/2003/instance"><head><meta http-equiv="content-type" content="text/html" /><title></title></head><body><div style="margin-top:30pt;"></div><div style="display:none;"><ix:header><ix:hidden><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:EntityCentralIndexKey" id="Tc_EDRNr98QuUilJiF3yzRuag_2_1">0001437402</ix:nonNumeric><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:AmendmentFlag" id="Tc_3lwAlaiATEaGzTv8zS594A_3_1">false</ix:nonNumeric></ix:hidden><ix:references><link:schemaRef xlink:href="ardx-20201112.xsd" xlink:type="simple"></link:schemaRef></ix:references><ix:resources><xbrli:context id="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw"><xbrli:entity><xbrli:identifier scheme="http://www.sec.gov/CIK">0001437402</xbrli:identifier></xbrli:entity><xbrli:period><xbrli:startDate>2020-11-12</xbrli:startDate><xbrli:endDate>2020-11-12</xbrli:endDate></xbrli:period></xbrli:context></ix:resources></ix:header></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;padding-bottom:1pt;padding-top:1pt;text-align:center;border-bottom:1.0pt solid #000000;border-top:3.0pt solid #000000;margin:0pt;"><span style="font-size:1pt;font-weight:bold;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><span style="font-size:3pt;visibility:hidden;">&#8203;</span></p><a id="_bd177d49_48ff_44be_b896_948702b2801d"></a><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-size:16pt;font-weight:bold;">UNITED STATES</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-size:16pt;font-weight:bold;">SECURITIES AND EXCHANGE COMMISSION</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 10pt 0pt;"><b style="font-size:12pt;font-weight:bold;">Washington, D.C. 20549</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;padding-bottom:1pt;text-align:center;border-bottom:1px solid #000000;margin:0pt 0pt 10pt 0pt;"><span style="font-size:1pt;font-weight:bold;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:16pt;text-align:center;margin:0pt 0pt 10pt 0pt;"><b style="font-weight:bold;">FORM </b><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:DocumentType" id="Narr_kyspmptgakuQkHah3xo4LQ"><b style="font-weight:bold;">8-K</b></ix:nonNumeric></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;padding-bottom:1pt;text-align:center;border-bottom:1px solid #000000;margin:0pt 0pt 10pt 0pt;"><span style="font-size:1pt;font-weight:bold;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-size:12pt;font-weight:bold;">CURRENT REPORT</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><b style="font-size:12pt;font-weight:bold;">Pursuant to Section&#160;13 or 15(d)</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 10pt 0pt;"><b style="font-size:12pt;font-weight:bold;">of the Securities Exchange Act of 1934</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:12pt;text-align:center;margin:0pt 0pt 10pt 0pt;"><b style="font-weight:bold;">Date of Report (Date of earliest event reported): </b><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" format="ixt:datemonthdayyearen" name="dei:DocumentPeriodEndDate" id="Narr_AxHr9NgJmEefRTUyku4HUg"><b style="font-weight:bold;">November 12, 2020</b></ix:nonNumeric></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;padding-bottom:1pt;text-align:center;border-bottom:1px solid #000000;margin:0pt 0pt 10pt 0pt;"><span style="font-size:1pt;font-weight:bold;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:22pt;text-align:center;margin:0pt;"><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:EntityRegistrantName" id="Narr_T2jqwtguVUayrm1NJuf6Yg"><b style="font-weight:bold;">ARDELYX, INC.</b></ix:nonNumeric></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 10pt 0pt;"><b style="font-weight:bold;">(Exact name of registrant as specified in its charter)</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;padding-bottom:1pt;text-align:center;border-bottom:1px solid #000000;margin:0pt 0pt 10pt 0pt;"><span style="font-size:1pt;visibility:hidden;">&#8203;</span></p><a id="_69f9713d_515e_451d_abd4_58555d9c25ac"></a><a id="Tc_qi3rAISnikC94kBVzKmhsw_2_0"></a><a id="Tc_lWdZZBRh2kK3fkEKcI_P2g_2_1"></a><a id="Tc_qgsdgPfb6EyYaRdZlHCiIg_2_2"></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:33.4%;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:top;width:33.29%;margin:0pt;padding:0pt;"><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:33.29%;margin:0pt;padding:0pt;"><div style="height:1pt;overflow:hidden;overflow-wrap:break-word;position:relative;"><div style="position:absolute;top:0pt;width:100%;"></div></div></td></tr><tr><td style="vertical-align:bottom;width:33.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" format="ixt-sec:stateprovnameen" name="dei:EntityIncorporationStateCountryCode" id="Tc_aGTlyiyUk0Sfk0bMPXl7iQ_1_0"><b style="font-weight:bold;">Delaware</b></ix:nonNumeric></p></td><td style="vertical-align:top;width:33.29%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:EntityFileNumber" id="Tc_Zf0cw9nT7EitZ8wLqAmy-Q_1_1"><b style="font-weight:bold;">001-36485</b></ix:nonNumeric></p></td><td style="vertical-align:top;width:33.29%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:EntityTaxIdentificationNumber" id="Tc_5RoI3ivarEm4GBxMGo80sw_1_2"><b style="font-weight:bold;">26-1303944</b></ix:nonNumeric></p></td></tr><tr><td style="vertical-align:top;width:33.4%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">(State or other jurisdiction<br />of incorporation)</b></p></td><td style="vertical-align:top;width:33.29%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">(Commission<br />File Number)</b></p></td><td style="vertical-align:top;width:33.29%;margin:0pt;padding:0pt;"><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;text-align:center;margin:0pt;"><b style="font-weight:bold;">(IRS Employer<br />Identification Number)</b></p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:8pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:EntityAddressAddressLine1" id="Narr_h7abYxzUNUGkX69UKSnojw"><b style="font-weight:bold;">34175 Ardenwood Blvd.</b></ix:nonNumeric><b style="font-weight:bold;"> </b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt;"><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:EntityAddressCityOrTown" id="Narr_NPiSfS5l2kiB22CuhxgsiQ"><b style="font-weight:bold;">Fremont</b></ix:nonNumeric><b style="font-weight:bold;">, </b><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:EntityAddressStateOrProvince" id="Narr_ArLDkkI1o0SVkD4wKz2CWg"><b style="font-weight:bold;">CA</b></ix:nonNumeric><b style="font-weight:bold;"> </b><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:EntityAddressPostalZipCode" id="Narr_Wu-faq5OPkiFu-8MzIL-4A"><b style="font-weight:bold;">94555</b></ix:nonNumeric></p><p style="font-family:'Times New Roman','Times','serif';font-size:8pt;text-align:center;margin:0pt 0pt 10pt 0pt;"><b style="font-weight:bold;">(Address of principal executive offices, including Zip Code)</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;text-align:center;margin:0pt 0pt 10pt 0pt;"><b style="font-weight:bold;">Registrant&#8217;s telephone number, including area code: (</b><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:CityAreaCode" id="Narr_4yzSuUu0yk2igono_jtUyQ"><b style="font-weight:bold;">510</b></ix:nonNumeric><b style="font-weight:bold;">)&#160;</b><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:LocalPhoneNumber" id="Narr_M_r27ET3jEikHKrGZU2bGw"><b style="font-weight:bold;">745-1700</b></ix:nonNumeric></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;padding-bottom:1pt;text-align:center;border-bottom:1px solid #000000;margin:0pt 0pt 10pt 0pt;"><span style="font-size:1pt;font-weight:bold;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;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="_5bfe3de6_ad85_4ad2_8391_50c8e43cb449"></a><a id="Tc__3MVz85Awkah_8-dXNpuWg_1_1"></a><a id="Tc_e1XGux0jj06uarNsZ356jA_2_1"></a><a id="Tc_t65Y3AnAXE2vJpicQJRZhw_3_1"></a><a id="Tc_VFwktVg87UOJRgjrq_C-3w_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 contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" format="ixt-sec:boolballotbox" name="dei:WrittenCommunications" id="Tc_aXJPMAS_REq3Iq094HuDmw_1_0"><span style="font-family:'Segoe UI Symbol';">&#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:10pt;margin:0pt 0pt 2pt 0pt;">Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) </p></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 contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" format="ixt-sec:boolballotbox" name="dei:SolicitingMaterial" id="Tc_D2KwUgK8YUKJRSGbnmszfQ_2_0"><span style="font-family:'Segoe UI Symbol';">&#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:10pt;margin:0pt 0pt 2pt 0pt;">Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) </p></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 contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" format="ixt-sec:boolballotbox" name="dei:PreCommencementTenderOffer" id="Tc_-G0p9eqVWESufFi35Uct2g_3_0"><span style="font-family:'Segoe UI Symbol';">&#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:10pt;margin:0pt 0pt 2pt 0pt;">Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) </p></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;"><ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" format="ixt-sec:boolballotbox" name="dei:PreCommencementIssuerTenderOffer" id="Tc_uaOVLAYpcU-Mh9rf8VtJ3Q_4_0"><span style="font-family:'Segoe UI Symbol';">&#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:10pt;margin:0pt;">Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) </p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:8pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;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;">Emerging growth company&#160;&#160;<ix:nonNumeric contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" format="ixt-sec:boolballotbox" name="dei:EntityEmergingGrowthCompany" id="Narr_2hU2u75xzUuXELoWyH2dtA"><span style="font-family:'Segoe UI Symbol';">&#9744;</span></ix:nonNumeric></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;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:8pt;visibility:hidden;">&#8203;</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 4pt 0pt;">Securities registered pursuant to Section 12(b) of the Act:</p><a id="_9f6996f1_1313_4772_a53d_6ceccb4266c3"></a><a id="Tc_HdiGRiz7UU-bioHdNZYdTw_1_0"></a><a id="Tc_P2RAaHS_WEa9mry50kbVHA_1_2"></a><a id="Tc_2-OroP44gEKOGPq8XOBTMQ_1_4"></a><table style="border-collapse:collapse;font-size:16pt;height:max-content;margin-left:auto;margin-right:auto;width:100%;"><tr style="height:1pt;"><td style="vertical-align:top;width:32.45%;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:2.78%;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:1pt;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 style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:1pt;visibility:hidden;">&#8203;</span></p></div></div></td><td style="vertical-align:top;width:38.46%;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></tr><tr><td style="vertical-align:top;width:32.45%;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:8pt;text-align:center;margin:0pt 0pt 2.2pt 0pt;"><b style="font-weight:bold;">Title of each class</b></p></td><td style="vertical-align:top;width:2.78%;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:8pt;font-weight:bold;visibility:hidden;">&#8203;</span></p></td><td 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:8pt;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:8pt;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:8pt;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 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 contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:Security12bTitle" id="Tc_zlDtZ_LbEUq0I35JoKYrRA_2_0">Common Stock, par value $0.0001</ix:nonNumeric></p></td><td style="vertical-align:top;width:2.78%;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="visibility:hidden;">&#8203;</span></p></td><td style="vertical-align:top;width:23.41%;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 contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" name="dei:TradingSymbol" id="Tc_DvORl1iFrUCEx8hGbp9zbw_2_2">ARDX</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="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 contextRef="Duration_11_12_2020_To_11_12_2020_zPTTtLkEoU-9O5VAIP3ZWw" format="ixt-sec:exchnameen" name="dei:SecurityExchangeName" id="Tc_Q-9uPkNSA0ycDagj3AJSVg_2_4">The Nasdaq Global Market</ix:nonNumeric></p></td></tr></table><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt;"><span style="font-size:3pt;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;font-family:'Times New Roman','Times','serif';line-height:0pt;margin:0pt;"><span style="font-size:0pt;visibility:hidden;">&#8203;</span></p><a id="_5687aeb0_10c6_46cf_a1f4_baa7121130aa"></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 8.01</b>&#160;&#160;&#160;&#160;&#160;&#160;&#160;<b style="font-weight:bold;">Other Events.</b></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 10pt 0pt;"><span style="white-space:pre-wrap;">On November 12, 2020, Ardelyx, Inc. (the &#8220;Company&#8221; or &#8220;Ardelyx&#8221;), a specialized biopharmaceutical company focused on developing first-in-class medicines to improve treatment for people with cardiorenal diseases, updated its progress with respect to its small molecule potassium secretagogue program, RDX013, for the potential treatment of hyperkalemia.  The Company noted that it has completed a Phase 1 clinical study evaluating the safety and pharmacodynamics of RDX013 in 112 healthy volunteers.  The data from the Phase 1 clinical study showed that RDX013 was generally safe and well-tolerated, and that a decrease in urine potassium and an increase in stool potassium excretion were observed in subjects treated with RDX013.  The results of the Phase 1 clinical trial support the Company&#8217;s decision to proceed with a Phase 2 clinical study evaluating RDX013 in hyperkalemic patients with chronic kidney disease, or CKD.  The Company currently expects to initiate the Phase 2 study in the next several months.</span></p><p style="font-family:'Times New Roman','Times','serif';font-size:10pt;margin:0pt 0pt 6pt 0pt;">The Company also provided an update of its progress in a pipeline research program, RDX020, targeting a bicarbonate exchange inhibitor to treat metabolic acidosis, noting that the Company has identified several lead compounds that have been determined to be potent, selective and proprietary inhibitors.</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="_1d89009e_2467_4cb4_a3cd_4c71a75b2c44"></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;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="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;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: November 12,&#160;2020</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="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></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>
[{"type": "8-K", "sequence": "1", "filename": "ardx-20201112x8k.htm", "description": "8-K", "secsgml_size_bytes": 29466}]
{"company-data": {"conformed-name": "ARDELYX, INC.", "cik": "0001437402", "assigned-sic": "2834", "irs-number": "000000000", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-36485", "film-number": "201307998"}, "business-address": {"street1": "34175 ARDENWOOD BLVD.", "city": "FREMONT", "state": "CA", "zip": "94555", "phone": "510-745-7047"}, "mail-address": {"street1": "34175 ARDENWOOD BLVD.", "city": "FREMONT", "state": "CA", "zip": "94555"}, "former-company": {"former-conformed-name": "NTERYX INC", "date-changed": "20080611"}}
​
​
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):
November 12, 2020
​
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
,
CA
94555
(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))
​
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.  ☐
​
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
​
​
Item 8.01
Other Events.
On November 12, 2020, Ardelyx, Inc. (the "Company" or "Ardelyx"), a specialized biopharmaceutical company focused on developing first-in-class medicines to improve treatment for people with cardiorenal diseases, updated its progress with respect to its small molecule potassium secretagogue program, RDX013, for the potential treatment of hyperkalemia.  The Company noted that it has completed a Phase 1 clinical study evaluating the safety and pharmacodynamics of RDX013 in 112 healthy volunteers.  The data from the Phase 1 clinical study showed that RDX013 was generally safe and well-tolerated, and that a decrease in urine potassium and an increase in stool potassium excretion were observed in subjects treated with RDX013.  The results of the Phase 1 clinical trial support the Company's decision to proceed with a Phase 2 clinical study evaluating RDX013 in hyperkalemic patients with chronic kidney disease, or CKD.  The Company currently expects to initiate the Phase 2 study in the next several months.
The Company also provided an update of its progress in a pipeline research program, RDX020, targeting a bicarbonate exchange inhibitor to treat metabolic acidosis, noting that the Company has identified several lead compounds that have been determined to be potent, selective and proprietary inhibitors.
​
​
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: November 12, 2020
ARDELYX, INC.
By:
/s/ Elizabeth Grammer
Elizabeth Grammer
Chief Legal and Administrative Officer
​
​
​