Atlas Venture Life Science Advisors, LLC Long-Term Concentrated

Name: Atlas Venture Life Science Advisors, LLC Q4 2025 13F Filing | 13F Explorer
Creator: Atlas Venture Life Science Advisors, LLC
Published: 2026-02-13

Location: Cambridge, MA

CIK: 0001917529 · Show all filings

Period: Q4 2025 (← Previous) (Next →)

Filing Date: Feb 13, 2026

Total Value: $865M (100.0% shares, 0.0% debt)

Holdings (8)

KYMR Kymera Therapeutics, Inc. 41.9%

Value $363M Shares 4,659,874 Est. Cost $58.25 Unrealized +15.9%

DYN Dyne Therapeutics, Inc. 20.6%

Value $179M Shares 9,130,465 Est. Cost $13.88 Unrealized +36.5%

SION Sionna Therapeutics, Inc. 14.2%

Value $123M Shares 2,995,602 Est. Cost $16.34 Unrealized +132.1%

IRON Disc Medicine, Inc. 13.9%

Value $120M Shares 1,513,875 Est. Cost $48.39 Unrealized +74.6%

DAWN Day One Biopharmaceuticals, Inc. 6.9%

Value $59.77M Shares 6,412,560 Est. Cost $19.68 Unrealized -57.5%

KRRO Korro Bio, Inc. 1.1%

Value $9.109M Shares 1,137,149 Est. Cost $33.30 Unrealized -29.8%

QTTB Q32 Bio, Inc. 0.8%

Value $6.946M Shares 2,092,106 Est. Cost $13.78 Unrealized -79.5%

— Generation Bio, Co. 0.5%

Value $4.703M Shares 827,946 Est. Cost $5.68 Unrealized —

Ticker	Issuer	Shares	Value	%	Est. Cost	Unrealized	Class	CUSIP
KYMR	Kymera Therapeutics, Inc.	4,659,874	$363M	41.9%	$58.25	+15.9%	Common Stock	501575104
DYN	Dyne Therapeutics, Inc.	9,130,465	$179M	20.6%	$13.88	+36.5%	Common Stock	26818M108
SION	Sionna Therapeutics, Inc.	2,995,602	$123M	14.2%	$16.34	+132.1%	Common Stock	829401108
IRON	Disc Medicine, Inc.	1,513,875	$120M	13.9%	$48.39	+74.6%	Common Stock	254604101
DAWN	Day One Biopharmaceuticals, Inc.	6,412,560	$59.77M	6.9%	$19.68	-57.5%	Common Stock	23954D109
KRRO	Korro Bio, Inc.	1,137,149	$9.109M	1.1%	$33.30	-29.8%	Common Stock	500946108
QTTB	Q32 Bio, Inc.	2,092,106	$6.946M	0.8%	$13.78	-79.5%	Common Stock	746964105
—	Generation Bio, Co.	827,946	$4.703M	0.5%	$5.68	—	Common Stock	37148K209