<SEC-DOCUMENT>0001209191-17-038124.txt : 20170606
<SEC-HEADER>0001209191-17-038124.hdr.sgml : 20170606
<ACCEPTANCE-DATETIME>20170606162713
ACCESSION NUMBER:		0001209191-17-038124
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170602
FILED AS OF DATE:		20170606
DATE AS OF CHANGE:		20170606

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Ra Pharmaceuticals, Inc.
		CENTRAL INDEX KEY:			0001481512
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				262908274
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		87 CAMBRIDGE PARK DRIVE
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02140
		BUSINESS PHONE:		(617) 401-4060

	MAIL ADDRESS:	
		STREET 1:		87 CAMBRIDGE PARK DRIVE
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02140

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:	001-37926
		FILM NUMBER:		17894414

	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

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:	001-37926
		FILM NUMBER:		17894415

	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
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-06-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001481512</issuerCik>
        <issuerName>Ra Pharmaceuticals, Inc.</issuerName>
        <issuerTradingSymbol>RARX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001297709</rptOwnerCik>
            <rptOwnerName>Novartis Bioventures Ltd</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NOVARTIS INTERNATIONAL</rptOwnerStreet1>
            <rptOwnerStreet2>AG 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>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>2017-06-02</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>14867</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>23.4714</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2325471</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-06-05</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4780</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>23.1146</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2320691</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Reflects sales of ordinary shares executed in multiple transactions at prices ranging from $23.16 to $23.80 on June 2, 2017 and $22.87 to $23.40 on June 5, 2017. The prices reported reflect the weighted average sale prices. 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 board of directors of Novartis Bioventures Ltd. has sole voting and investment control and power over such securities. None of the members of its board of directors has individual voting or investment power with respect to such securities and each disclaims beneficial ownership of such securities. Novartis Bioventures Ltd. is an indirectly owned subsidiary of Novartis AG.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Simon Zivi, Authorized Signatory /s/ Laurieann Chaikowsky, Authorized Signatory</signatureName>
        <signatureDate>2017-06-06</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Simon Zivi, Authorized Signatory /s/ Laurieann Chaikowsky, Authorized Signatory</signatureName>
        <signatureDate>2017-06-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
