<SEC-DOCUMENT>0000899243-18-009442-index.html : 20180404
<SEC-HEADER>0000899243-18-009442.hdr.sgml : 20180404
<ACCEPTANCE-DATETIME>20180404162407
ACCESSION NUMBER:		0000899243-18-009442
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20180402
FILED AS OF DATE:		20180404
DATE AS OF CHANGE:		20180404

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Rock Springs Capital LLC
		CENTRAL INDEX KEY:			0001735397
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38433
		FILM NUMBER:		18737481

	BUSINESS ADDRESS:	
		STREET 1:		650 SOUTH EXETER STREET
		STREET 2:		SUITE 1070
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21202
		BUSINESS PHONE:		410-220-0142

	MAIL ADDRESS:	
		STREET 1:		650 SOUTH EXETER STREET
		STREET 2:		SUITE 1070
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21202

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Rock Springs Capital Management LP
		CENTRAL INDEX KEY:			0001595725
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38433
		FILM NUMBER:		18737480

	BUSINESS ADDRESS:	
		STREET 1:		650 SOUTH EXETER STREET
		STREET 2:		SUITE 1070
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21202
		BUSINESS PHONE:		4102200129

	MAIL ADDRESS:	
		STREET 1:		650 SOUTH EXETER STREET
		STREET 2:		SUITE 1070
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21202

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Rock Springs Capital Master Fund LP
		CENTRAL INDEX KEY:			0001735393
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38433
		FILM NUMBER:		18737482

	BUSINESS ADDRESS:	
		STREET 1:		650 SOUTH EXETER STREET
		STREET 2:		SUITE 1070
		CITY:			BALTIMORE
		STATE:			MD
		ZIP:			21202
		BUSINESS PHONE:		410-220-0142

	MAIL ADDRESS:	
		STREET 1:		190 ELGIN AVENUE
		CITY:			GEORGE TOWN
		STATE:			E9
		ZIP:			KY1 9001

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Homology Medicines, Inc.
		CENTRAL INDEX KEY:			0001661998
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				473468154
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		45 WIGGINS AVE.
		CITY:			BEDFORD
		STATE:			MA
		ZIP:			01730
		BUSINESS PHONE:		857-305-1825

	MAIL ADDRESS:	
		STREET 1:		45 WIGGINS AVE.
		CITY:			BEDFORD
		STATE:			MA
		ZIP:			01730
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
Document 1 - file: doc4.html

Document 1 - RAW XML: doc4.xml

</DOCUMENT>
</SEC-DOCUMENT>