Institutions / EcoR1 Capital, LLC

EcoR1 Capital, LLC

CIK 1587114 · Institutionalso an insider · as of Dec 31, 2025

Portfolio value

$2.19B

Positions

As of

Dec 31, 2025

Top holdings

Dec 31, 2025View all 28 →

Company	Class	Value	Shares	% of portfolio
Zymeworks Inc.	—	$604.81M	22,970,388	27.6%
AnaptysBio, Inc.	—	$382.03M	7,880,094	17.4%
Jazz Pharmaceuticals PLC	—	$290.10M	1,706,469	13.2%
Crinetics Pharmaceuticals, Inc.	—	$199.61M	4,288,120	9.1%
Centessa Pharmaceuticals PLC	—	$77.91M	3,115,000	3.6%
Crispr Therapeutics AG	—	$72.85M	1,389,276	3.3%
MBX Biosciences, Inc.MBX	Common Stock	$66.98M	2,123,604	3.1%
Immunome Inc.	—	$61.34M	2,855,590	2.8%
Oric Pharmaceuticals, Inc.	—	$55.04M	6,728,116	2.5%
Galapagos NV	—	$54.51M	1,667,119	2.5%
Xencor Inc	—	$49.77M	3,251,112	2.3%
BridgeBio Oncology Therapeutics, Inc.BBOT	Common Stock	$35.35M	2,823,126	1.6%
Eton Pharmaceuticals, Inc.	—	$34.34M	2,030,544	1.6%
CG Oncology, Inc.	—	$32.05M	772,000	1.5%
Zenas BioPharma, Inc.ZBIO	Common Stock	$28.67M	789,500	1.3%
Neurogene Inc.NGNE	Common Stock	$26.19M	1,271,342	1.2%
Structure Therapeutics Inc.GPCR	ADR	$23.26M	334,380	1.1%
Vaxcyte, Inc.	—	$20.76M	450,000	0.9%
Aquestive Therapeutics, Inc.AQST	Common Stock	$16.96M	2,625,000	0.8%
Voyager Therapeutics, Inc.	—	$15.73M	4,002,847	0.7%
Atara Biotherapeutics, Inc.ATRA	Common Stock	$10.37M	573,183	0.5%
Mannkind Corp	—	$9.41M	1,660,000	0.4%
Nuvation Bio Inc	—	$8.63M	963,333	0.4%
Evolus, Inc.	—	$4.49M	675,000	0.2%
iBio, Inc.IBIO	Common Stock	$4.30M	2,228,000	0.2%

Activity

Dec 31, 2025

InsidersInstitutions

This fund's 13F position changes — what it's buying and selling.

No quarter-over-quarter changes yet — position changes appear once we've ingested two consecutive 13F filings for this manager. We currently hold 1 quarter of holdings.

Insider transactions

Also files Forms 3 / 4 / 5

Date	Action	Company	Value	Shares Δ	Position after	Impact
Jan 12, 2026	Buy	AKTS Aktis Oncology, Inc. Common Stock	$37.40M	+2.1M +91.50%	4,348,658 7.87% of shares	high
Jan 12, 2026	Buy	AKTS Aktis Oncology, Inc. Common Stock	$2.60M	+144K +71.20%	347,305 0.63% of shares	high
Jan 12, 2026	Other	AKTS Aktis Oncology, Inc. Class A Common Stock	—	+86K	86,222 0.16% of shares	low
Jan 12, 2026	Other	AKTS Aktis Oncology, Inc. Class A Common Stock	—	+965K	965,190 1.75% of shares	low
Jan 12, 2026	Other	AKTS Aktis Oncology, Inc. Series B Redeemable Convertible Preferred Stock	—	-103K -100.00%	0 0.00% of shares	low
Jan 12, 2026	Other	AKTS Aktis Oncology, Inc. Series B Redeemable Convertible Preferred Stock	—	-2.4M -100.00%	0 0.00% of shares	low
Jan 12, 2026	Other	AKTS Aktis Oncology, Inc. Series A Redeemable Convertible Preferred Stock	—	-489K -100.00%	0 0.00% of shares	low
Jan 12, 2026	Other	AKTS Aktis Oncology, Inc. Series A Redeemable Convertible Preferred Stock	—	-997K -100.00%	0 0.00% of shares	low
Jan 12, 2026	Other	AKTS Aktis Oncology, Inc. Series A Redeemable Convertible Preferred Stock	—	-9.9M -100.00%	0 0.00% of shares	low
Jan 12, 2026	Other	AKTS Aktis Oncology, Inc. Common Stock	—	+129K	128,506 0.23% of shares	low