XTX Topco’s Sionna Therapeutics SION Stock Holding History

XTX Topco’s Portfolio SION Stock Details SION Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q1	$944K	Buy	23,551 +18,625	+378%	+$711K	0.02%	1462
2025 Q4	$203K	Buy	+4,926	New	+$187K	0.01%	2395

Other funds holding SION

RCM

RA Capital Management Boston, Massachusetts $9.44B AUM 157.3% 1-Year Est. Return

TGA

TPG GP A Fort Worth, Texas $3.68B AUM 14.99% 1-Year Est. Return

OrbiMed New York $5.05B AUM 125.28% 1-Year Est. Return

Viking Global Investors Stamford, Connecticut $35.7B AUM 21.3% 1-Year Est. Return

AVLSA

Atlas Venture Life Science Advisors Cambridge, Massachusetts $790M AUM 223.66% 1-Year Est. Return

Enavate Sciences Menlo Park, California $352M AUM 220.14% 1-Year Est. Return

Jennison Associates New York $145B AUM 34.61% 1-Year Est. Return

JP Morgan Chase New York $1.56T AUM 27.86% 1-Year Est. Return

BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return

Citadel Advisors Miami, Florida $618B AUM 30.34% 1-Year Est. Return

XTX Topco's SION Position: Q1 2026 in Review

XTX Topco increased its Sionna Therapeutics (SION) stake by 378% in Q1 2026, buying an estimated $711K and bringing the position to 23,551 shares worth $944K. The position accounts for 0.02% of the portfolio, ranked #1462.

XTX Topco first reported a position in SION in Q4 2025 and has held it in 2 quarters since. 122 funds tracked by Wall St. Rank hold SION as of Q1 2026.

XTX Topco held 23,551 shares of Sionna Therapeutics worth $944K as of Q1 2026.
XTX Topco bought 18,625 Sionna Therapeutics shares in Q1 2026, an estimated $711K.
Sionna Therapeutics made up 0.02% of XTX Topco's portfolio in Q1 2026, its #1462 holding.
XTX Topco first reported a position in Sionna Therapeutics in Q4 2025 and has held it in 2 quarters since.
122 funds tracked by Wall St. Rank held Sionna Therapeutics as of Q1 2026.

Based on XTX Topco's 13F filing for Q1 2026, filed 15 May 2026.