<SEC-DOCUMENT>0000925421-18-000300.txt : 20180822
<SEC-HEADER>0000925421-18-000300.hdr.sgml : 20180822
<ACCEPTANCE-DATETIME>20180822163448
ACCESSION NUMBER:		0000925421-18-000300
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180820
FILED AS OF DATE:		20180822
DATE AS OF CHANGE:		20180822

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Novartis Bioventures Ltd
		CENTRAL INDEX KEY:			0001297709
		STATE OF INCORPORATION:			D0
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38130
		FILM NUMBER:		181032834

	BUSINESS ADDRESS:	
		STREET 1:		C/O NOVARTIS INTERNATIONAL AG
		STREET 2:		WSJ-200.220
		CITY:			CH-4002 BASEL
		STATE:			V8
		ZIP:			0000000000
		BUSINESS PHONE:		41-61-324-6210

	MAIL ADDRESS:	
		STREET 1:		C/O NOVARTIS INTERNATIONAL AG
		STREET 2:		WSJ-200.220
		CITY:			CH-4002 BASEL
		STATE:			V8
		ZIP:			0000000000

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			NOVARTIS AG
		CENTRAL INDEX KEY:			0001114448
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		STATE OF INCORPORATION:			V8
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38130
		FILM NUMBER:		181032835

	BUSINESS ADDRESS:	
		STREET 1:		LICHTSTRASSE 35
		CITY:			BASEL
		STATE:			V8
		ZIP:			CH 4056
		BUSINESS PHONE:		01141613241111

	MAIL ADDRESS:	
		STREET 1:		LICHTSTRASSE 35
		CITY:			BASEL
		STATE:			V8
		ZIP:			CH 4056

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AILERON THERAPEUTICS INC
		CENTRAL INDEX KEY:			0001420565
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		281 ALBANY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		617-995-0900

	MAIL ADDRESS:	
		STREET 1:		281 ALBANY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-08-20</periodOfReport>

    <issuer>
        <issuerCik>0001420565</issuerCik>
        <issuerName>AILERON THERAPEUTICS INC</issuerName>
        <issuerTradingSymbol>ALRN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001297709</rptOwnerCik>
            <rptOwnerName>Novartis Bioventures Ltd</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NOVARTIS INTERNATIONAL AG</rptOwnerStreet1>
            <rptOwnerStreet2>WSJ-200.220</rptOwnerStreet2>
            <rptOwnerCity>BASEL</rptOwnerCity>
            <rptOwnerState>V8</rptOwnerState>
            <rptOwnerZipCode>CH-4002</rptOwnerZipCode>
            <rptOwnerStateDescription>SWITZERLAND</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001114448</rptOwnerCik>
            <rptOwnerName>NOVARTIS AG</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>LICHTSTRASSE 35</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BASEL</rptOwnerCity>
            <rptOwnerState>V8</rptOwnerState>
            <rptOwnerZipCode>CH 4056</rptOwnerZipCode>
            <rptOwnerStateDescription>SWITZERLAND</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-08-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>20388</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.30</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2396882</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Reflects sales of common stock executed in multiple transactions at prices ranging from $2.06 to $2.53. The price reported reflects the weighted average sale price. The Reporting Persons hereby undertake to provide upon request to the Securities and Exchange Commission staff, the Issuer or a security holder of the Issuer full information regarding the number of shares and prices at which the sales were effected.</footnote>
        <footnote id="F2">The shares are directly owned by Novartis Bioventures Ltd. Novartis Bioventures Ltd is a wholly-owned indirect subsidiary of Novartis AG, which is an indirect beneficial owner of the reported securities.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Bartosz Dzikowski, Secretary of the Board of Novartis Bioventures Ltd</signatureName>
        <signatureDate>2018-08-22</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Florian Muellershausen, Authorized Signatory on behalf of Novartis Bioventures Ltd</signatureName>
        <signatureDate>2018-08-22</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Bartosz Dzikowski, Authorized Signatory on behalf of Novartis AG</signatureName>
        <signatureDate>2018-08-22</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Florian Muellershausen, Authorized Signatory on behalf of Novartis AG</signatureName>
        <signatureDate>2018-08-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
