EcoR1 Capital, LLC Q1 2019 Filing

Filed May 15, 2019

Portfolio Value

$1.1T

Holdings

41

Report Date

Q1 2019

Filing Type

13F-HR

All Holdings (41 positions)

#StockSharesValue% PortfolioType
1
ARGXARGENX SE
825,087$103.0B9.50%
2
KURAKURA ONCOLOGY INC
5,276,753$87.5B8.07%
3
MRTXEURMIRATI THERAPEUTICS INC
1,000,000$73.3B6.76%
4
CRSPCRISPR THERAPEUTICS AG
1,878,277$67.1B6.18%
5
XNCRXENCOR INC
2,059,429$64.0B5.90%
6
SPARK THERAPEUTICS INC
529,000$60.2B5.55%
7
IRWDIRONWOOD PHARMACEUTICALS INC
4,397,168$59.5B5.48%
8
FIBROGEN INC
1,000,000$54.4B5.01%Put
9
DICERNA PHARMACEUTICALS INC
3,316,407$48.6B4.48%
10
ASNDASCENDIS PHARMA A S
360,819$42.5B3.91%
11
ASNDASCENDIS PHARMA A S
360,000$42.4B3.91%Put
12
RAREULTRAGENYX PHARMACEUTICAL INC
497,899$34.5B3.18%
13
MIRATI THERAPEUTICS INC
348,900$25.6B2.36%Call
14
MYOKARDIA INC
478,574$24.9B2.29%
15
FIBROGEN INC
440,800$24.0B2.21%Call
16
ASMBASSEMBLY BIOSCIENCES INC
1,153,599$22.7B2.09%
17
CLDNEUREIGER BIOPHARMACEUTICALS INC
1,595,643$22.3B2.06%
18
MAGENTA THERAPEUTICS INC
1,277,787$21.0B1.94%
19
GOSSGOSSAMER BIO INC
772,096$16.7B1.54%
20
CHIASMA INC
3,043,827$15.8B1.46%
21
KZRKEZAR LIFE SCIENCES INC
856,471$15.2B1.40%
22
IRWDIRONWOOD PHARMACUTICALS INC
1,084,600$14.7B1.35%Call
23
HARPOON THERAPEUTICS INC
1,336,423$12.7B1.17%
24
RCUSARCUS BIOSCIENCES INC
990,146$12.4B1.14%
25
MERSANA THERAPEUTICS INC
2,300,000$12.1B1.12%
26
RUBYUSDRUBIUS THERAPEUTICS INC
646,228$11.7B1.08%
27
RYTMRHYTHM PHARMACEUTICALS INC
400,838$11.0B1.01%
28
SURFUSDSURFACE ONCOLOGY INC
2,263,488$10.8B1.00%
29
FGENEURFIBROGEN INC
168,382$9.2B0.84%
30
PRTAPROTHENA CORP PLC
726,519$8.8B0.81%
31
RCKTROCKET PHARMACEUTICALS INC
450,000$7.9B0.73%
32
I9DNARBUTUS BIOPHARMA CORP
2,172,883$7.8B0.72%
33
ADURO BIOTECH INC
1,939,390$7.7B0.71%
34
UNITY BIOTECHNOLOGY INC
906,614$7.4B0.68%
35
SRRKSCHOLAR ROCK HOLDING CORP
338,668$6.4B0.59%
36
AQUINOX PHARMACEUTICALS INC
2,265,880$6.1B0.56%
37
CURIS INC
2,982,208$5.9B0.55%
38
ZLABZAI LAB LTD
78,519$2.3B0.21%
39
VCELVERICEL CORP
131,001$2.3B0.21%
40
SIENNA BIOPHARMACEUTICALS INC
800,000$1.9B0.17%
41
ARVNARVINAS INC
50,000$738.0M0.07%