<SEC-DOCUMENT>0001012975-13-000535.txt : 20131125
<SEC-HEADER>0001012975-13-000535.hdr.sgml : 20131125
<ACCEPTANCE-DATETIME>20131125173418
ACCESSION NUMBER:		0001012975-13-000535
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20131121
FILED AS OF DATE:		20131125
DATE AS OF CHANGE:		20131125

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MEI Pharma, Inc.
		CENTRAL INDEX KEY:			0001262104
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				510407811
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		11975 EL CAMINO REAL
		STREET 2:		SUITE 101
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92130
		BUSINESS PHONE:		858-792-6300

	MAIL ADDRESS:	
		STREET 1:		11975 EL CAMINO REAL
		STREET 2:		SUITE 101
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92130

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MARSHALL EDWARDS INC
		DATE OF NAME CHANGE:	20030902

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HUNT RONALD
		CENTRAL INDEX KEY:			0001247851

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50484
		FILM NUMBER:		131241925

	MAIL ADDRESS:	
		STREET 1:		C/O CREDIT SUISSE 1ST BOSTON PRV EQY
		STREET 2:		11 MADISON AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10010

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			NIEDEL JAMES
		CENTRAL INDEX KEY:			0001231092

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50484
		FILM NUMBER:		131241926

	MAIL ADDRESS:	
		STREET 1:		C/O CREDIT SUISSE PRIVATE EQUITY INC
		STREET 2:		11 MADISON AVE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10010

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Delagardelle Jeani
		CENTRAL INDEX KEY:			0001441563

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50484
		FILM NUMBER:		131241929

	MAIL ADDRESS:	
		STREET 1:		C/O NEW LEAF VENTURE PARTNERS, L.L.C.
		STREET 2:		2500 SAND HILL ROAD, SUITE 203
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			New Leaf Venture Associates II, L.P.
		CENTRAL INDEX KEY:			0001441858
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50484
		FILM NUMBER:		131241931

	BUSINESS ADDRESS:	
		STREET 1:		TIMES SQUARE TOWER
		STREET 2:		7 TIMES SQUARE, SUITE 3502
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036
		BUSINESS PHONE:		646 871-6400

	MAIL ADDRESS:	
		STREET 1:		TIMES SQUARE TOWER
		STREET 2:		7 TIMES SQUARE, SUITE 3502
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			New Leaf Ventures II, L.P.
		CENTRAL INDEX KEY:			0001441439
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50484
		FILM NUMBER:		131241932

	BUSINESS ADDRESS:	
		STREET 1:		TIMES SQUARE TOWER
		STREET 2:		7 TIMES SQUARE, SUITE 3502
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036
		BUSINESS PHONE:		(646) 871-6400

	MAIL ADDRESS:	
		STREET 1:		TIMES SQUARE TOWER
		STREET 2:		7 TIMES SQUARE, SUITE 3502
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			New Leaf Venture Management II, L.L.C.
		CENTRAL INDEX KEY:			0001441857
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50484
		FILM NUMBER:		131241930

	BUSINESS ADDRESS:	
		STREET 1:		TIMES SQUARE TOWER
		STREET 2:		7 TIMES SQUARE, SUITE 3502
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036
		BUSINESS PHONE:		646 871-6400

	MAIL ADDRESS:	
		STREET 1:		TIMES SQUARE TOWER
		STREET 2:		7 TIMES SQUARE, SUITE 3502
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Lathi Vijay K
		CENTRAL INDEX KEY:			0001340806

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50484
		FILM NUMBER:		131241924

	MAIL ADDRESS:	
		STREET 1:		C/O NEW LEAF VENTURE PARTNERS
		STREET 2:		2500 SAND HILL ROAD, SUITE 203
		CITY:			MENLO PARK
		STATE:			CA
		ZIP:			94025

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Ratcliffe Liam
		CENTRAL INDEX KEY:			0001547100

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50484
		FILM NUMBER:		131241928

	MAIL ADDRESS:	
		STREET 1:		C/O NEW LEAF VENTURE PARTNERS
		STREET 2:		7 TIMES SQUARE - SUITE 3502
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Chambon Philippe O.
		CENTRAL INDEX KEY:			0001192212

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50484
		FILM NUMBER:		131241927

	MAIL ADDRESS:	
		STREET 1:		C/O NEW LEAF VENTURE PARTNERS
		STREET 2:		7 TIMES SQUARE, SUITE 3502
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036

	FORMER NAME:	
		FORMER CONFORMED NAME:	CHAMBON PHILIPPE
		DATE OF NAME CHANGE:	20020924
</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>2013-11-21</periodOfReport>

    <issuer>
        <issuerCik>0001262104</issuerCik>
        <issuerName>MEI Pharma, Inc.</issuerName>
        <issuerTradingSymbol>MEIP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001441439</rptOwnerCik>
            <rptOwnerName>New Leaf Ventures II, L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NEW LEAF VENTURES</rptOwnerStreet1>
            <rptOwnerStreet2>TIMES SQUARE TOWER, 7 TIMES SQ, STE 3502</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10036</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001441858</rptOwnerCik>
            <rptOwnerName>New Leaf Venture Associates II, L.P.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NEW LEAF VENTURES</rptOwnerStreet1>
            <rptOwnerStreet2>TIMES SQUARE TOWER, 7 TIMES SQ, STE 3502</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10036</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001441857</rptOwnerCik>
            <rptOwnerName>New Leaf Venture Management II, L.L.C.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NEW LEAF VENTURES</rptOwnerStreet1>
            <rptOwnerStreet2>TIMES SQUARE TOWER, 7 TIMES SQ, STE 3502</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10036</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001192212</rptOwnerCik>
            <rptOwnerName>Chambon Philippe O.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NEW LEAF VENTURES</rptOwnerStreet1>
            <rptOwnerStreet2>TIMES SQUARE TOWER, 7 TIMES SQ, STE 3502</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10036</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001231092</rptOwnerCik>
            <rptOwnerName>NIEDEL JAMES</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NEW LEAF VENTURES</rptOwnerStreet1>
            <rptOwnerStreet2>TIMES SQUARE TOWER, 7 TIMES SQ, STE 3502</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10036</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001247851</rptOwnerCik>
            <rptOwnerName>HUNT RONALD</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NEW LEAF VENTURES</rptOwnerStreet1>
            <rptOwnerStreet2>TIMES SQUARE TOWER, 7 TIMES SQ, STE 3502</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10036</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001340806</rptOwnerCik>
            <rptOwnerName>Lathi Vijay K</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NEW LEAF VENTURES</rptOwnerStreet1>
            <rptOwnerStreet2>2500 SAND HILL ROAD, SUITE 203</rptOwnerStreet2>
            <rptOwnerCity>MENLO PARK</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94025</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001441563</rptOwnerCik>
            <rptOwnerName>Delagardelle Jeani</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NEW LEAF VENTURES</rptOwnerStreet1>
            <rptOwnerStreet2>2500 SAND HILL ROAD, SUITE 203</rptOwnerStreet2>
            <rptOwnerCity>MENLO PARK</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94025</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001547100</rptOwnerCik>
            <rptOwnerName>Ratcliffe Liam</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NEW LEAF VENTURES</rptOwnerStreet1>
            <rptOwnerStreet2>TIMES SQUARE TOWER, 7 TIMES SQ, STE 3502</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10036</rptOwnerZipCode>
            <rptOwnerStateDescription></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>2013-11-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>365000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>8.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1680475</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The securities are directly held by New Leaf Ventures II, L.P. (&quot;NLV II&quot;) and indirectly held by New Leaf Venture Associates II, L.P. (&quot;NLV Associates II&quot;), the sole general partner of NLV II, New Leaf Venture Management II, L.L.C. (&quot;NLV Management II&quot;), the sole general partner of NLV Associates II, and the individual managers of NLV Management II (NLV Associates II, NLV Management II and the individual managers of NLV Management II each, an &quot;Indirect Reporting Person&quot;). The individual managers of NLV Management II filing jointly with NLV II, NLV Associates II and NLV Management II are Philippe O. Chambon, James Niedel, Ronald Hunt, Vijay Lathi, Jeani Delagardelle and Liam Ratcliffe. Each Indirect Reporting Person disclaims beneficial ownership of such portion of the NLV II shares in which such Indirect Reporting Person has no actual pecuniary interest therein.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Craig L. Slutzkin, Chief Financial Officer of New Leaf Venture Management II, L.L.C., the sole general partner of New Leaf Venture Associates II, L.P., the sole general partner of New Leaf Ventures II, L.P.</signatureName>
        <signatureDate>2013-11-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Craig L. Slutzkin, Chief Financial Officer of New Leaf Venture Management II, L.L.C., the sole general partner of New Leaf Venture Associates II, L.P.</signatureName>
        <signatureDate>2013-11-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Craig L. Slutzkin, Chief Financial Officer of New Leaf Venture Management II, L.L.C.</signatureName>
        <signatureDate>2013-11-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Craig L. Slutzkin, as Attorney-in-Fact for Philippe O. Chambon</signatureName>
        <signatureDate>2013-11-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Craig L. Slutzkin, as Attorney-in-Fact for James Niedel</signatureName>
        <signatureDate>2013-11-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Craig L. Slutzkin, as Attorney-in-Fact for Ronald Hunt</signatureName>
        <signatureDate>2013-11-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Craig L. Slutzkin, as Attorney-in-Fact for Vijay Lathi</signatureName>
        <signatureDate>2013-11-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Craig L. Slutzkin, as Attorney-in-Fact for Jeani Delagardelle</signatureName>
        <signatureDate>2013-11-25</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Craig L. Slutzkin, as Attorney-in-Fact for Liam Ratcliffe</signatureName>
        <signatureDate>2013-11-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
