<SEC-DOCUMENT>0001638599-17-001008.txt : 20171006
<SEC-HEADER>0001638599-17-001008.hdr.sgml : 20171006
<ACCEPTANCE-DATETIME>20171006155831
ACCESSION NUMBER:		0001638599-17-001008
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20171005
FILED AS OF DATE:		20171006
DATE AS OF CHANGE:		20171006

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BAKER FELIX
		CENTRAL INDEX KEY:			0001087940

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38223
		FILM NUMBER:		171127196

	MAIL ADDRESS:	
		STREET 1:		BAKER BROS. ADVISORS LP
		STREET 2:		860 WASHINGTON STREET 3RD FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10014

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BAKER JULIAN
		CENTRAL INDEX KEY:			0001087939

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38223
		FILM NUMBER:		171127199

	MAIL ADDRESS:	
		STREET 1:		BAKER BROS. ADVISORS LP
		STREET 2:		860 WASHINGTON STREET 3RD FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10014

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Baker Bros. Advisors (GP) LLC
		CENTRAL INDEX KEY:			0001580575
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38223
		FILM NUMBER:		171127197

	BUSINESS ADDRESS:	
		STREET 1:		860 WASHINGTON STREET
		STREET 2:		3RD FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10014
		BUSINESS PHONE:		(212)339-5600

	MAIL ADDRESS:	
		STREET 1:		860 WASHINGTON STREET
		STREET 2:		3RD FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10014

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BAKER BROS. ADVISORS LP
		CENTRAL INDEX KEY:			0001263508
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38223
		FILM NUMBER:		171127198

	BUSINESS ADDRESS:	
		STREET 1:		860 WASHINGTON STREET
		STREET 2:		3RD FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10014
		BUSINESS PHONE:		2123395600

	MAIL ADDRESS:	
		STREET 1:		860 WASHINGTON STREET
		STREET 2:		3RD FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10014

	FORMER NAME:	
		FORMER CONFORMED NAME:	BAKER BROS ADVISORS LLC
		DATE OF NAME CHANGE:	20030911

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			RHYTHM PHARMACEUTICALS, INC.
		CENTRAL INDEX KEY:			0001649904
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				462159271
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		500 BOYLSTON STREET
		STREET 2:		11TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116
		BUSINESS PHONE:		857-264-4280

	MAIL ADDRESS:	
		STREET 1:		500 BOYLSTON STREET
		STREET 2:		11TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	RHYTHM METABOLIC, INC.
		DATE OF NAME CHANGE:	20150803
</SEC-HEADER>
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    <footnotes>
        <footnote id="F1">Represents shares of common stock of Rhythm Pharmaceuticals, Inc. (the &quot;Issuer&quot;) received upon conversion of shares of the Issuer's Series A Convertible Preferred Stock (&quot;Series A Preferred&quot;) which automatically convert into common stock of the Issuer on a 9.17 for 1 basis (the &quot;Conversion Ratio&quot;) without consideration upon the closing of the initial public offering of the Issuer (&quot;IPO&quot;).</footnote>
        <footnote id="F2">After giving effect to the transactions reported herein, and as a result of their ownership interest in Baker Biotech Capital (GP), LLC, Julian C. Baker and Felix J. Baker may be deemed to have an indirect pecuniary interest in shares of the Issuer's common stock reported in column 5 of Table I directly held by 667, L.P. (&quot;667&quot;), a limited partnership of which the sole general partner is Baker Biotech Capital, L.P., a limited partnership of which the sole general partner is Baker Biotech Capital (GP), LLC, due to Baker Biotech Capital, L.P.'s right to receive an allocation of a portion of the profits from 667.</footnote>
        <footnote id="F3">After giving effect to the transactions reported herein, and as a result of their ownership interest in Baker Brothers Life Sciences Capital (GP), LLC, Julian C. Baker and Felix J. Baker may be deemed to have an indirect pecuniary interest in shares of the Issuer's common stock reported in column 5 of Table I directly held by Baker Brothers Life Sciences, L.P. (&quot;Life Sciences&quot; and together with 667, the &quot;Funds&quot;), a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital, L.P., a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital (GP), LLC, due to Baker Brothers Life Sciences Capital, L.P.'s right to receive an allocation of a portion of the profits from Life Sciences.</footnote>
        <footnote id="F4">On October 5, 2017, 667 and Life Sciences purchased 87,809 and 797,191 shares of common stock of the Issuer at a price of $17.00 per share, respectively, pursuant to an IPO.</footnote>
        <footnote id="F5">Effective upon the closing of the Issuer's IPO, the Series A Preferred shares of the Issuer were converted at the Conversion Ratio without consideration into the number of common shares of the Issuer shown in Column 7. The Series A Preferred shares did not have an expiration date and were convertible at any time, at the holder's election, into common shares of the Issuer.</footnote>
        <footnote id="F6">Pursuant to Instruction 4(c)(iii), this response has been left blank.</footnote>
        <footnote id="F7">Baker Bros. Advisors LP (the &quot;Adviser&quot;) serves as the Investment Adviser to the Funds. In connection with the services provided by the Adviser, the Adviser receives an asset-based management fee that does not confer any pecuniary interest in the securities held by the Funds. Baker Bros. Advisors (GP) LLC (the &quot;Adviser GP&quot;) is the Adviser's sole general partner. Julian C. Baker and Felix J. Baker are principals of the Adviser GP. The Adviser has complete and unlimited discretion and authority with respect to the investment and voting power of the securities held by the Funds.</footnote>
        <footnote id="F8">The general partners of the Funds relinquished to the Adviser all discretion and authority with respect to the investment and voting power of the securities held by the Funds. Julian C. Baker, Felix J. Baker, the Adviser GP and the Adviser disclaim beneficial ownership of the securities held directly by the Funds except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that any of Julian C. Baker, Felix J. Baker, the Adviser GP or the Adviser is a beneficial owner of such securities for purposes of Section 16 or any other purpose.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>By: Baker Bros. Advisors LP, Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing</signatureName>
        <signatureDate>2017-10-06</signatureDate>
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    <ownerSignature>
        <signatureName>By: Baker Bros. Advisors (GP) LLC, Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing</signatureName>
        <signatureDate>2017-10-06</signatureDate>
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    <ownerSignature>
        <signatureName>/s/ Felix J. Baker</signatureName>
        <signatureDate>2017-10-06</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Julian C. Baker</signatureName>
        <signatureDate>2017-10-06</signatureDate>
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