OrbiMed Advisors UPB Position
Active3-Fund ConvergenceOrbiMed Advisors held their position in Upstream Bio, Inc. (UPB) in Q4 2025, holding $154.6M worth of shares across 5,693,589 shares.
The position was first reported in Q4 2024 and has been tracked across 5 quarterly 13F filings.
UPB is a convergence signal: 3 specialist biotech funds hold this stock, suggesting high institutional conviction.
There is an upcoming Phase 2 readout for Verekitug in 532 days (Sep 30, 2027), making the timing of OrbiMed's position particularly relevant.
Short interest stands at 15.8% of float with 2.5 days to cover, indicating significant bearish positioning against OrbiMed's long thesis.
About Upstream Bio, Inc.
Upstream Bio, Inc., a clinical-stage biotechnology company, develops treatments for inflammatory diseases that focuses on severe respiratory disorders. It develops verekitug, a monoclonal antibody that targets and inhibits the thymic stromal lymphopoietin receptor. The company also develops therapies to treat severe asthma, chronic rhinosinusitis with nasal polyps, and chronic obstructive pulmonary disease. Upstream Bio, Inc. was incorporated in 2021 and is based in Waltham, Massachusetts.
Full company profile →Short Interest
15.8%
2.5 days to cover
OrbiMed Advisors UPB Position History
Frequently Asked Questions
Does OrbiMed Advisors own UPB?
Yes. As of Q4 2025, OrbiMed Advisors holds 5,693,589 shares of Upstream Bio, Inc. (UPB) valued at $154.6M. This data comes from their SEC 13F filing.
How many hedge funds own UPB?
3 specialist biotech hedge funds currently hold UPB, including Deep Track Capital, EcoR1 Capital. When 3 or more specialist funds hold the same stock, BiotechEdge flags it as a convergence signal.
When did OrbiMed Advisors first buy UPB?
OrbiMed Advisors's position in UPB was first reported in Q4 2024. 13F filings are reported with a 45-day delay, so the actual purchase may have occurred earlier in the quarter.
Is OrbiMed Advisors's UPB position increasing or decreasing?
OrbiMed Advisors held their UPB position unchanged in the most recent quarter.
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