<SEC-DOCUMENT>0001972481-25-000231.txt : 20251002
<SEC-HEADER>0001972481-25-000231.hdr.sgml : 20251002
<ACCEPTANCE-DATETIME>20251002181150
ACCESSION NUMBER:		0001972481-25-000231
CONFORMED SUBMISSION TYPE:	144
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20251002
DATE AS OF CHANGE:		20251002

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			IONIS PHARMACEUTICALS INC
		CENTRAL INDEX KEY:			0000874015
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		ORGANIZATION NAME:           	03 Life Sciences
		EIN:				330336973
		STATE OF INCORPORATION:			CA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		144
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	000-19125
		FILM NUMBER:		251371119

	BUSINESS ADDRESS:	
		STREET 1:		2855 GAZELLE COURT
		CITY:			CARLSBAD
		STATE:			CA
		ZIP:			92010
		BUSINESS PHONE:		7609319200

	MAIL ADDRESS:	
		STREET 1:		2855 GAZELLE COURT
		CITY:			CARLSBAD
		STATE:			CA
		ZIP:			92010

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ISIS PHARMACEUTICALS INC
		DATE OF NAME CHANGE:	19930328

REPORTING-OWNER:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			O'NEIL PATRICK R.
		CENTRAL INDEX KEY:			0001564926
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		144

	MAIL ADDRESS:	
		STREET 1:		C/O IONIS PHARMACEUTICALS, INC.
		STREET 2:		2855 GAZELLE COURT
		CITY:			CARLSBAD
		STATE:			CA
		ZIP:			92010
</SEC-HEADER>
<DOCUMENT>
<TYPE>144
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
  <headerData>
    <submissionType>144</submissionType>
    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001564926</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>


    </filerInfo>
  </headerData>
  <formData>
    <issuerInfo>
      <issuerCik>0000874015</issuerCik>
      <issuerName>IONIS PHARMACEUTICALS INC</issuerName>
      <secFileNumber>000-19125</secFileNumber>
      <issuerAddress>
        <com:street1>2855 GAZELLE COURT</com:street1>
        <com:city>CARLSBAD</com:city>
        <com:stateOrCountry>CA</com:stateOrCountry>
        <com:zipCode>92010</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>7609319200</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>O'NEIL PATRICK R.</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>Common Stock</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Stifel Nicolaus &amp; Company Inc</name>
        <address>
          <com:street1>501 N Broadway</com:street1>
          <com:city>St. Louis</com:city>
          <com:stateOrCountry>MO</com:stateOrCountry>
          <com:zipCode>63102</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>78105</noOfUnitsSold>
      <aggregateMarketValue>5286865.00</aggregateMarketValue>
      <noOfUnitsOutstanding>159391229</noOfUnitsOutstanding>
      <approxSaleDate>10/02/2025</approxSaleDate>
      <securitiesExchangeName> Nasdaq </securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common Stock</securitiesClassTitle>
      <acquiredDate>01/02/2020</acquiredDate>
      <natureOfAcquisitionTransaction>Option Exercise</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>34461</amountOfSecuritiesAcquired>
      <paymentDate>10/02/2025</paymentDate>
      <natureOfPayment> Cash </natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common Stock</securitiesClassTitle>
      <acquiredDate>01/04/2021</acquiredDate>
      <natureOfAcquisitionTransaction> Option Exercise </natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired> Issuer </nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>30203</amountOfSecuritiesAcquired>
      <paymentDate>10/02/2025</paymentDate>
      <natureOfPayment> Cash </natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common Stock</securitiesClassTitle>
      <acquiredDate>01/04/2024</acquiredDate>
      <natureOfAcquisitionTransaction> Option Exercise </natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>10200</amountOfSecuritiesAcquired>
      <paymentDate>10/02/2025</paymentDate>
      <natureOfPayment> Cash </natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common Stock</securitiesClassTitle>
      <acquiredDate>01/01/2016</acquiredDate>
      <natureOfAcquisitionTransaction> Owned Shares </natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired> Issuer </nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>3241</amountOfSecuritiesAcquired>
      <paymentDate>01/01/2016</paymentDate>
      <natureOfPayment> Cash </natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Patrick O'Neil</name>
        <address>
          <com:street1> 2855 Gazette Ct </com:street1>
          <com:city> Carlsbad </com:city>
          <com:stateOrCountry>CA</com:stateOrCountry>
          <com:zipCode>92010</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle> Common Stock </securitiesClassTitle>
      <saleDate>09/02/2025</saleDate>
      <amountOfSecuritiesSold>13050</amountOfSecuritiesSold>
      <grossProceeds>711418.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Patrick O'Neil</name>
        <address>
          <com:street1>2855 Gazette Ct</com:street1>
          <com:city>Carlsbad</com:city>
          <com:stateOrCountry>CA</com:stateOrCountry>
          <com:zipCode>92010</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common Stock</securitiesClassTitle>
      <saleDate>09/03/2025</saleDate>
      <amountOfSecuritiesSold>76850</amountOfSecuritiesSold>
      <grossProceeds>4685201.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Patrick O'Neil</name>
        <address>
          <com:street1>2855 Gazette Ct</com:street1>
          <com:city>Carlsbad</com:city>
          <com:stateOrCountry>CA</com:stateOrCountry>
          <com:zipCode>92010</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle> Common Stock </securitiesClassTitle>
      <saleDate>09/09/2025</saleDate>
      <amountOfSecuritiesSold>21000</amountOfSecuritiesSold>
      <grossProceeds>1355660.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Patrick O'Neil</name>
        <address>
          <com:street1>2855 Gazette Ct</com:street1>
          <com:city>Carlsbad</com:city>
          <com:stateOrCountry>CA</com:stateOrCountry>
          <com:zipCode>92010</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle> Common Stock </securitiesClassTitle>
      <saleDate>09/12/2025</saleDate>
      <amountOfSecuritiesSold>1700</amountOfSecuritiesSold>
      <grossProceeds>109787.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Patrick O'Neil</name>
        <address>
          <com:street1>2855 Gazette Ct</com:street1>
          <com:city>Carlsbad</com:city>
          <com:stateOrCountry>CA</com:stateOrCountry>
          <com:zipCode>92010</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle> Common Stock </securitiesClassTitle>
      <saleDate>09/29/2025</saleDate>
      <amountOfSecuritiesSold>10473</amountOfSecuritiesSold>
      <grossProceeds>675945.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Patrick O'Neil</name>
        <address>
          <com:street1>2855 Gazette Ct</com:street1>
          <com:city>Carlsbad</com:city>
          <com:stateOrCountry>CA</com:stateOrCountry>
          <com:zipCode>92010</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common Stock</securitiesClassTitle>
      <saleDate>09/30/2025</saleDate>
      <amountOfSecuritiesSold>14827</amountOfSecuritiesSold>
      <grossProceeds>958976.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>10/02/2025</noticeDate>
      <planAdoptionDates>
        <planAdoptionDate>05/01/2025</planAdoptionDate>
      </planAdoptionDates>
      <signature>/s/ James Weimer, as a duly authorized representative of STIFEL, as attorney-in-fact for Patrick O'Neil</signature>
    </noticeSignature>
  </formData>
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</SEC-DOCUMENT>
