<SEC-DOCUMENT>0001104659-18-031224-index.html : 20180508
<SEC-HEADER>0001104659-18-031224.hdr.sgml : 20180508
<ACCEPTANCE-DATETIME>20180508142552
ACCESSION NUMBER:		0001104659-18-031224
CONFORMED SUBMISSION TYPE:	SC 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20180508
DATE AS OF CHANGE:		20180508

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Alkermes plc.
		CENTRAL INDEX KEY:			0001520262
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				981007018
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-86627
		FILM NUMBER:		18814016

	BUSINESS ADDRESS:	
		STREET 1:		CONNAUGHT HOUSE
		STREET 2:		1 BURLINGTON ROAD
		CITY:			DUBLIN 4
		STATE:			L2
		ZIP:			00000
		BUSINESS PHONE:		00-353-1-772-8000

	MAIL ADDRESS:	
		STREET 1:		CONNAUGHT HOUSE
		STREET 2:		1 BURLINGTON ROAD
		CITY:			DUBLIN 4
		STATE:			L2
		ZIP:			00000

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ANTLER SCIENCE TWO PLC
		DATE OF NAME CHANGE:	20110804

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Antler Science Two Ltd
		DATE OF NAME CHANGE:	20110509

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PRIMECAP MANAGEMENT CO/CA/
		CENTRAL INDEX KEY:			0000763212
		IRS NUMBER:				953868081

	FILING VALUES:
		FORM TYPE:		SC 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		177 EAST COLORADO BLVD.
		STREET 2:		11TH FLOOR
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91105
		BUSINESS PHONE:		6263049222

	MAIL ADDRESS:	
		STREET 1:		177 EAST COLORADO BLVD.
		STREET 2:		11TH FLOOR
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91105
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G/A
<SEQUENCE>1
<FILENAME>a18-13041_1sc13ga.htm
<DESCRIPTION>SC 13G/A
<TEXT>
Document 1 - file: a18-13041_1sc13ga.htm

</DOCUMENT>
</SEC-DOCUMENT>