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Livermore
Livermore
ZHEN

EcoR1 Capital, LLC

SEC CIK
0001587114
Latest filing
Aug 14, 2026

Holdings in Q3 2023

Holdings as of Sep 30, 2023, filed Nov 14, 2023. Long positions only; changes compare share counts with Q2 2023.

Institution overview
Positions
49
−2 vs. Q2 2023
Portfolio value
$2.93B
−$858.1M (−22.6%) vs. Q2 2023
Filed
Nov 14, 2023
SEC
Holdings of EcoR1 Capital, LLC in Q3 2023
SecurityClassSharesValue% of portfolioShare changeActionHistory
PRTAProthena Corp Public Ltd CoSHS11,584,280$558.9M19.1%00.0%UnchangedHistory
APLSApellis Pharmaceuticals, Inc.COM10,899,859$414.6M14.1%+5,448,212+99.9%AddedHistory
MRTXMirati Therapeutics, Inc.COM5,748,399$250.4M8.5%+5,748,399NewHistory
LKFTLakefront Biotherapeutics NVSPON ADR5,756,268$198.9M6.8%00.0%UnchangedHistory
RVMDRevolution Medicines, Inc.COM5,577,863$154.4M5.3%−1,620,837−22.5%ReducedHistory
ANABAnaptysbio, IncCOM7,521,024$135.1M4.6%00.0%UnchangedHistory
ACADAcadia Pharmaceuticals IncCOM5,991,479$124.9M4.3%00.0%UnchangedHistory
ARVNArvinas, Inc.COM5,467,063$107.4M3.7%+1,449,275+36.1%AddedHistory
XNCRXencor IncCOM5,282,516$106.4M3.6%00.0%UnchangedHistory
TNGXTango Therapeutics, Inc.COM8,721,636$98.2M3.3%+4,674,522+115.5%AddedHistory
ZYMEZymeworks Inc.COM13,437,473$85.2M2.9%00.0%UnchangedHistory
SWTXSpringWorks Therapeutics, Inc.COM3,460,208$80.0M2.7%00.0%UnchangedHistory
KURAKura Oncology, Inc.COM5,806,871$53.0M1.8%00.0%UnchangedHistory
JAZZJazz Pharmaceuticals plcSHS USD368,411$47.7M1.6%00.0%UnchangedHistory
CRNXCrinetics Pharmaceuticals, Inc.COM1,530,263$45.5M1.6%+200,000+15.0%AddedHistory
CNTACentessa Pharmaceuticals plcSPONSORED ADS5,618,779$36.4M1.2%00.0%UnchangedHistory
RLAYRelay Therapeutics, Inc.COM4,163,824$35.0M1.2%00.0%UnchangedHistory
MORFMorphic Holding, Inc.COM1,480,190$33.9M1.2%−2,366,774−61.5%ReducedHistory
VYGRVoyager Therapeutics, Inc.COM3,851,507$29.8M1.0%00.0%UnchangedHistory
NMRANeumora Therapeutics, Inc.COM2,071,450$29.2M1.0%+2,071,450NewHistory
ALECAlector, Inc.COM4,056,548$26.3M0.9%00.0%UnchangedHistory
NUVBNuvation Bio Inc.COM CL A19,209,643$25.7M0.9%+5,313,100+38.2%AddedHistory
MRSNMersana Therapeutics, Inc.COM19,364,688$24.6M0.8%+19,364,688NewHistory
OVIDOvid Therapeutics Inc.COM6,117,400$23.5M0.8%00.0%UnchangedHistory
LENZLENZ Therapeutics, Inc.COM8,538,446$21.2M0.7%00.0%UnchangedHistory
AVIRAtea Pharmaceuticals, Inc.COM6,995,861$21.0M0.7%00.0%UnchangedHistory
ORICOric Pharmaceuticals, Inc.COM3,418,068$20.7M0.7%00.0%UnchangedHistory
EWTXEdgewise Therapeutics, Inc.COM3,493,194$20.0M0.7%00.0%UnchangedHistory
THRDThird Harmonic Bio, Inc.COM2,982,444$19.1M0.6%+893,664+42.8%AddedHistory
SLRNACELYRIN, Inc.COM1,402,201$14.3M0.5%+1,402,201NewHistory
ALLOAllogene Therapeutics, Inc.COM4,488,200$14.2M0.5%00.0%UnchangedHistory
TCRXTScan Therapeutics, Inc.COM5,000,000$12.8M0.4%00.0%UnchangedHistory
DCPHDeciphera Pharmaceuticals, Inc.COM993,000$12.6M0.4%+993,000NewHistory
GBIOGeneration Bio Co.COM2,046,867$7.76M0.3%00.0%UnchangedHistory
GOSSGossamer Bio, Inc.COM9,195,404$7.66M0.3%+9,195,404NewHistory
PHATPhathom Pharmaceuticals, Inc.COM700,000$7.26M0.2%00.0%UnchangedHistory
NGMNGM Biopharmaceuticals IncCOM6,435,518$6.89M0.2%00.0%UnchangedHistory
PRMEPrime Medicine, Inc.COM600,000$5.72M0.2%00.0%UnchangedHistory
PRQRProQR Therapeutics N.V.SHS EURO2,980,016$3.87M0.1%00.0%UnchangedHistory
PRLDPrelude Therapeutics IncCOM1,157,452$3.58M0.1%00.0%UnchangedHistory
ALGSAligos Therapeutics, Inc.COM3,948,360$2.95M0.1%00.0%UnchangedHistory
HOOKHOOKIPA Pharma Inc.COM4,595,024$2.83M0.1%00.0%UnchangedHistory
SYRESpyre Therapeutics, Inc.COM NEW199,996$2.45M0.1%00.0%UnchangedConverted for a 1-for-25 splitHistory
ALLKAllakos Inc.COM748,900$1.70M0.1%00.0%UnchangedHistory
TPSTTempest Therapeutics, Inc.COM931,000$283.7K<0.1%−192,434−17.1%ReducedHistory
Nuvation Bio Inc.67080N119*W EXP 07/07/202963,333––00.0%Unchanged–
CareMax, Inc.14171W111*W EXP 06/08/202100,000––00.0%Unchanged–
Surrozen, Inc.86889P117*W EXP 08/01/20366,665––00.0%Unchanged–
NAMSWNewAmsterdam Pharma Co N.V.*W EXP 11/22/20266,665––00.0%UnchangedHistory

Options (2)

Puts and calls in the same filing. Amounts are the market value of the underlying shares, which is what 13F reports.

Option positions of EcoR1 Capital, LLC in Q3 2023
SecurityClassPutsCalls
APLSApellis Pharmaceuticals, Inc.COM–$27.9M
RVMDRevolution Medicines, Inc.COM–$866.4K

Sold out since Q2 2023 (8)

Positions held at the end of Q2 2023 that are gone from this filing.

Positions of EcoR1 Capital, LLC sold out since Q2 2023
SecurityClassShares in Q2 2023Value in Q2 2023% of portfolio in Q2 2023History
SRPTSarepta Therapeutics, Inc.COM3,660,798$419.2M11.1%History
BPMCBlueprint Medicines CorpCOM1,798,300$113.7M3.0%History
DYNDyne Therapeutics, Inc.COM798,701$8.99M0.2%History
ZNTLZentalis Pharmaceuticals, Inc.COM300,000$8.46M0.2%History
JANXJanux Therapeutics, Inc.COM452,590$5.37M0.1%History
FDMT4D Molecular Therapeutics, Inc.COM66,978$1.21M<0.1%History
PSTXPoseida Therapeutics, Inc.COM676,296$1.19M<0.1%History
KRONKronos Bio, Inc.COM326,780$562.1K<0.1%History