Rock Springs Capital Management LP Q4 2018 Filing

Filed February 14, 2019

Portfolio Value

$2.1B

Holdings

133

Report Date

Q4 2018

Filing Type

13F-HR

All Holdings (133 positions)

#	Stock	Shares	Value	% Portfolio
101	—BLUEBIRD BIO INC	45,000	$4.5M	0.21%
102	—MOMENTA PHARMACEUTICALS INC	400,000	$4.4M	0.21%
103	ADAPYADAPTIMMUNE THERAPEUTICS PLC	750,000	$4.3M	0.20%
104	INSM 1.75 01/15/25INSMED INC	6,000,000	$4.3M	0.20%
105	—MERSANA THERAPEUTICS INC	1,000,000	$4.1M	0.19%
106	—ALDER BIOPHARMACEUTICALS INC	5,000,000	$4.0M	0.19%
107	—MEDICINES CO	5,000,000	$3.8M	0.18%
108	—DERMIRA INC	517,000	$3.7M	0.18%
109	—ACHILLION PHARMACEUTICALS IN	2,325,000	$3.7M	0.17%
110	ARDXARDELYX INC	2,000,000	$3.6M	0.17%
111	DVAXDYNAVAX TECHNOLOGIES CORP	380,000	$3.5M	0.16%
112	—RESTORBIO INC	400,000	$3.4M	0.16%
113	—CLEMENTIA PHARMACEUTICALS IN	275,000	$3.2M	0.15%
114	SPROSPERO THERAPEUTICS INC	525,000	$3.2M	0.15%
115	—CORREVIO PHARMA CORP	1,200,000	$3.0M	0.14%
116	—LA JOLLA PHARMACEUTICAL CO	277,236	$2.6M	0.12%
117	—MEDICINES CO	3,000,000	$2.6M	0.12%
118	—PHASEBIO PHARMACEUTICALS INC	835,000	$2.6M	0.12%
119	CGENCOMPUGEN LTD	1,100,000	$2.4M	0.11%
120	—NABRIVA THERAPEUTICS PLC	1,600,000	$2.3M	0.11%
121	—PARATEK PHARMACEUTICALS INC	450,000	$2.3M	0.11%
122	ARVNARVINAS INC	150,000	$1.9M	0.09%
123	GTHXEURG1 THERAPEUTICS INC	100,000	$1.9M	0.09%
124	—CHIASMA INC	525,000	$1.6M	0.08%
125	SLDBSOLID BIOSCIENCES INC	58,999	$1.6M	0.07%
126	—THERAVANCE BIOPHARMA INC	1,500,000	$1.5M	0.07%
127	CRVSCORVUS PHARMACEUTICALS INC	400,000	$1.5M	0.07%
128	—PROTEOSTASIS THERAPEUTICS IN	400,000	$1.3M	0.06%
129	NBIX 2.25 05/15/24NEUROCRINE BIOSCIENCES INC	1,000,000	$1.2M	0.06%
130	—RADIUS HEALTH INC	1,500,000	$1.2M	0.05%
131	MGNXMACROGENICS INC	80,981	$1.0M	0.05%
132	—PACIRA PHARMACEUTICALS INC	1,000,000	$994K	0.05%
133	—DERMIRA INC	1,000,000	$775K	0.04%

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