Atlas Venture Life Science Advisors, LLC Long-Term Concentrated

Name: Atlas Venture Life Science Advisors, LLC Q3 2025 13F Filing | 13F Explorer
Creator: Atlas Venture Life Science Advisors, LLC
Published: 2025-11-13

Location: Cambridge, MA

CIK: 0001917529 · Show all filings

Period: Q3 2025 (← Previous) (Next →)

Filing Date: Nov 13, 2025

Total Value: $753M (100.0% shares, 0.0% debt)

Holdings (9)

KYMR Kymera Therapeutics, Inc. 36.8%

Value $277M Shares 4,896,462 Est. Cost $58.25 Unrealized -22.6%

IRON Disc Medicine, Inc. 18.8%

Value $142M Shares 2,142,617 Est. Cost $48.39 Unrealized +22.9%

DYN Dyne Therapeutics, Inc. 15.3%

Value $116M Shares 9,130,465 Est. Cost $13.88 Unrealized -17.8%

SION Sionna Therapeutics, Inc. 14.1%

Value $106M Shares 3,615,527 Est. Cost $16.34 Unrealized +33.1%

KRRO Korro Bio, Inc. 7.2%

Value $54.46M Shares 1,137,149 Est. Cost $33.30 Unrealized -33.4%

DAWN Day One Biopharmaceuticals, Inc. 6.0%

Value $45.33M Shares 6,430,257 Est. Cost $19.68 Unrealized -65.0%

— Generation Bio, Co. 0.7%

Value $5.067M Shares 827,946 Est. Cost $7.08 Unrealized —

QTTB Q32 Bio, Inc. 0.6%

Value $4.142M Shares 2,092,106 Est. Cost $13.78 Unrealized -86.1%

IMA ImageneBio, Inc. 0.4%

Value $3.079M Shares 377,814 Est. Cost $13.25 Unrealized 0.0%

Ticker	Issuer	Shares	Value	%	Est. Cost	Unrealized	Class	CUSIP
KYMR	Kymera Therapeutics, Inc.	4,896,462	$277M	36.8%	$58.25	-22.6%	Common Stock	501575104
IRON	Disc Medicine, Inc.	2,142,617	$142M	18.8%	$48.39	+22.9%	Common Stock	254604101
DYN	Dyne Therapeutics, Inc.	9,130,465	$116M	15.3%	$13.88	-17.8%	Common Stock	26818M108
SION	Sionna Therapeutics, Inc.	3,615,527	$106M	14.1%	$16.34	+33.1%	Common Stock	829401108
KRRO	Korro Bio, Inc.	1,137,149	$54.46M	7.2%	$33.30	-33.4%	Common Stock	500946108
DAWN	Day One Biopharmaceuticals, Inc.	6,430,257	$45.33M	6.0%	$19.68	-65.0%	Common Stock	23954D109
—	Generation Bio, Co.	827,946	$5.067M	0.7%	$7.08	—	Common Stock	37148K100
QTTB	Q32 Bio, Inc.	2,092,106	$4.142M	0.6%	$13.78	-86.1%	Common Stock	746964105
IMA	ImageneBio, Inc.	377,814	$3.079M	0.4%	$13.25	0.0%	Common Stock	45175G207