<SEC-DOCUMENT>0000874015-24-000197.txt : 20240904
<SEC-HEADER>0000874015-24-000197.hdr.sgml : 20240904
<ACCEPTANCE-DATETIME>20240904210629
ACCESSION NUMBER:		0000874015-24-000197
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20240202
FILED AS OF DATE:		20240904
DATE AS OF CHANGE:		20240904

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Schneider Eugene
		CENTRAL INDEX KEY:			0001838539
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19125
		FILM NUMBER:		241279611

	MAIL ADDRESS:	
		STREET 1:		C/O IONIS PHARMACEUTICALS
		STREET 2:		2855 GAZELLE CT
		CITY:			CARLSBAD
		STATE:			CA
		ZIP:			92010

ISSUER:		

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

	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
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2024-02-02</periodOfReport>

    <dateOfOriginalSubmission>2024-02-02</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000874015</issuerCik>
        <issuerName>IONIS PHARMACEUTICALS INC</issuerName>
        <issuerTradingSymbol>IONS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001838539</rptOwnerCik>
            <rptOwnerName>Schneider Eugene</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O IONIS PHARMACEUTICALS</rptOwnerStreet1>
            <rptOwnerStreet2>2855 GAZELLE CT</rptOwnerStreet2>
            <rptOwnerCity>CARLSBAD</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92010</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP, Chf Clinical Develop Ofcr</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2024-02-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2106</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>49.59</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>47659</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The original Form 4 filed on February 2, 2024 reported 2,071 restricted stock units sold by the reporting person which has been revised by this amendment to reflect
the actual amount of shares sold and beneficially owned by Mr. Schneider.</footnote>
        <footnote id="F2">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $49.58 to $49.60 inclusive. The
reporting person undertakes to provide to Ionis Pharmaceuticals, Inc. any security holder of Ionis Pharmaceuticals, Inc. or the staff of the Securities and Exchange
Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2) on this Form 4.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Patrick R. O'Neil, attorney-in-fact For: Eugene Schneider</signatureName>
        <signatureDate>2024-09-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
