RA Capital Management ACLX Position
Active6-Fund ConvergenceRA Capital Management trimmed their position in Arcellx Inc. (ACLX) in Q4 2025, holding $82.6M worth of shares across 1,267,156 shares.
The position was first reported in Q2 2024 and has been tracked across 7 quarterly 13F filings.
ACLX is a convergence signal: 6 specialist biotech funds hold this stock, suggesting high institutional conviction.
There is an upcoming Phase 2 readout for anitocabtagene-autoleucel in 261 days (Dec 31, 2026), making the timing of RA Capital's position particularly relevant.
Short interest stands at 10.9% of float with 1.0 days to cover, indicating significant bearish positioning against RA Capital's long thesis.
About Arcellx Inc.
Arcellx, Inc., a clinical-stage biotechnology company, engages in the development of various immunotherapies for patients with cancer and other incurable diseases. The company's lead ddCAR product candidate is CART-ddBCMA, which is in phase 1 clinical trial for the treatment of patients with relapsed or refractory (r/r) multiple myeloma (MM). It is also developing ACLX-001, an immunotherapeutic combination composed of ARC-T cells and bi-valent SparX proteins targeting BCMA to treat r/r MM; ACLX-002 and ACLX-003 for treating r/r acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS); and other AML/MDS product candidates, as well as solid tumor programs. The company was formerly known as Encarta Therapeutics, Inc. and changed its name to Arcellx, Inc. in January 2016. Arcellx, Inc. was incorporated in 2014 and is headquartered in Gaithersburg, Maryland.
Full company profile →Short Interest
10.9%
1.0 days to cover
RA Capital Management ACLX Position History
Frequently Asked Questions
Does RA Capital Management own ACLX?
Yes. As of Q4 2025, RA Capital Management holds 1,267,156 shares of Arcellx Inc. (ACLX) valued at $82.6M. This data comes from their SEC 13F filing.
How many hedge funds own ACLX?
6 specialist biotech hedge funds currently hold ACLX, including Perceptive Advisors, Cormorant Asset Management, Deep Track Capital and 2 more. When 3 or more specialist funds hold the same stock, BiotechEdge flags it as a convergence signal.
When did RA Capital Management first buy ACLX?
RA Capital Management's position in ACLX was first reported in Q2 2024. 13F filings are reported with a 45-day delay, so the actual purchase may have occurred earlier in the quarter.
Is RA Capital Management's ACLX position increasing or decreasing?
RA Capital Management trimmed their ACLX position in the most recent quarter, reducing by 1,769,371 shares.
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