Upstream Bio, Inc.
UPB evidence brief
What we can confirm
- BioSniper Score:
- 5.2 / 10
- Market Cap:
- $314.9M
- Lead Asset:
- verekitug (Phase 2)
What it means
What to watch
Prepared research question
What matters most for UPB—catalysts, financial risk and supporting evidence?
Traceable citations · Unknowns marked
BioSniper AI · UPB
Upstream Bio, Inc. (UPB) is a clinical-stage biotech company developing verekitug, a monoclonal antibody targeting the TSLP receptor, for severe respiratory indications including asthma, CRSwNP, and COPD.
Key risk: Single-product dependency
BioSniper Score
Based on 4 of 6 signals
Financial data as of Jun 30, 2026.
Tracking 1 pipeline candidate · 4 clinical trials for Upstream Bio, Inc..
Upstream Bio, Inc. (UPB) is a clinical-stage biotech company developing verekitug, a monoclonal antibody targeting the TSLP receptor, for severe respiratory indications including asthma, CRSwNP, and COPD.
- Upstream Bio's sole product candidate is verekitug, a monoclonal antibody targeting the receptor for thymic stromal lymphopoietin (TSLP) [sec_mda · as of 2026-08-11].
- As of 2026-06-30, the company reported cash & equivalents of $79.4M, total revenue of $0.8M, net income of -$39.7M, and shareholders' equity of $271.0M [sec].
- Phase 2 trials are ongoing for verekitug in severe asthma (VALIANT), CRSwNP (VIBRANT), and COPD, with top-line data from the CRSwNP trial reported in Q3 2025 [news · published 2025-08-06].
- The company expects expenses to increase as it advances clinical trials and seeks regulatory approval, and it will require additional funding to finance operations [sec_mda · as of 2026-08-11].
What works
- Verekitug is the only known clinical-stage monoclonal antibody targeting the TSLP receptor, which may offer a differentiated mechanism in respiratory inflammation [news · published 2025-09-01].
- The company has advanced verekitug into multiple Phase 2 trials across three indications (asthma, CRSwNP, COPD), diversifying its clinical pipeline [sec_mda · as of 2026-08-11].
- Upstream Bio reported a solid cash position of $79.4M as of 2026-06-30, providing runway for ongoing development activities [sec].
What to weigh
- Upstream Bio is entirely dependent on a single product candidate, verekitug, making it riskier than companies with multiple candidates [sec_mda · as of 2026-08-11].
- The company has not yet generated significant revenue ($0.8M as of 2026-06-30) and reported a net loss of $39.7M for the period, reflecting high R&D costs [sec].
- Upstream Bio will require additional funding to continue operations, and any delays or failures in verekitug's development could force program reductions or elimination [sec_mda · as of 2026-08-11].
From the filings
Quoted directly from source documents.
Verekitug is the only known clinical-stage monoclonal antibody targeting the TSLP receptor.
“the only known clinical-stage monoclonal antibody targeting the receptor for thymic stromal lymphopoietin (TSL”
News · September 1, 2025
The company's business depends entirely on verekitug.
“We currently have a single product candidate, verekitug, which is in clinical development for the treatment of severe asthma, chronic rhinosinusitis with nasal polyps ("CRSwNP"), and chronic obstructive pulmonary disease ("COPD"). Our business presently depends entirely on our ability to successfully develop, obtain regulatory approval for, and commercialize verekitug”
SEC MD&A · August 11, 2026
Upstream Bio expects expenses to increase and will need additional funding.
“We expect our expenses to continue to increase in connection with our ongoing activities, particularly as we conduct clinical trials of, and seek regulatory and marketing approval for, verekitug in multiple indications.”
SEC MD&A · August 11, 2026
Phase 2 CRSwNP trial top-line data was reported in Q3 2025.
“On track to report top-line data from Phase 2 trial in chronic rhinosinusitis with nasal polyps (CRSwNP) in the third quarter of 2025”
News · August 6, 2025
Catalyst timeline
- 2023-12-18 · Phase2_Start: VIBRANT (CRSwNP) — Phase 2 trial of verekitug in chronic rhinosinusitis with nasal polyps initiated.
- 2024-02-27 · Phase2_Start: VALIANT (Severe Asthma) — Phase 2 dose-ranging study of verekitug in severe asthma began.
- 2025-05-21 · Phase2_Start: Long-term extension of VALIANT — Long-term safety and efficacy extension study for patients who completed the VALIANT trial started.
- 2025-07-02 · Phase2_Start: Phase 2b trial — Phase 2b trial of verekitug initiated (indication not specified in catalyst block).
Risks & what to watch (3)›
Key risks
- Single-product dependency — Upstream Bio's entire business relies on verekitug; failure or delay of this candidate would severely impact the company [sec_mda · as of 2026-08-11].
- Funding need — The company will require additional capital to finance operations and may face delays or program cuts if unable to raise funds [sec_mda · as of 2026-08-11].
- No approved product yet — Verekitug is still in Phase 2; regulatory approval and commercialization are years away, with no guarantee of success [sec_mda · as of 2026-08-11].
What to watch
- Top-line data from the Phase 2 VALIANT trial in severe asthma, expected in Q1 2026 [news · published 2025-08-06].
- Progress of the Phase 2b trial in COPD, with first patient dosed in July 2025 [news · published 2025-08-06].
- Upcoming financial reports and any new financing rounds, as the company will need additional funding [sec_mda · as of 2026-08-11].
Sources: Catalysts · News · SEC MD&A · Generated September 27, 2026 · How we verify sources →
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Evidence & data
Score breakdownBased on 4 of 6 signals · derived from public data
Cash runway data unavailable
D/E 0.04 · 0% dilution
Lead: Phase 2
1 candidate
No upcoming catalysts tracked
0 buys · 5 sells (180d)
Pipeline
Regulatory
Financials
Institutional Holdings
Source: SEC Form 13F · as of Mar 2026Institutional holders
141
Total value held
$403.9M
| Holder | Shares | Value |
|---|---|---|
| fmr llc | 8,101,563 | $72.9M |
| orbimed advisors llc | 5,693,589 | $51.2M |
| blackrock, inc. | 3,370,689 | $30.3M |
| decheng capital llc | 2,724,868 | $24.5M |
| enavate sciences gp, llc | 2,459,703 | $22.1M |
| vanguard capital management llc | 1,873,574 | $16.9M |
| y-intercept (hong kong) ltd | 1,000,631 | $9.0M |
| federated hermes, inc. | 979,758 | $8.8M |
| geode capital management, llc | 950,617 | $8.6M |
| millennium management llc | 937,323 | $8.4M |
Showing top 10 of 141 institutional holders of Upstream Bio, Inc.. Open the full 13F history after sign-in.
Short Interest
as of Apr 20, 2026- % of float
- 11.3%
- Days to cover
- 3.3
- Shares short
- 3,435,261
- Daily short volume
- -
Short percent of float and days-to-cover reflect reported short positioning. Daily short volume is the exchange-reported short share of a single day's trading volume and is noisier. See the most-shorted biotech ranking →
UPB short interestGovernance
Frequently asked questions
What is the AI investment thesis for Upstream Bio, Inc.?
Upstream Bio, Inc. (UPB) is a clinical-stage biotech company developing verekitug, a monoclonal antibody targeting the TSLP receptor, for severe respiratory indications including asthma, CRSwNP, and COPD.
What is Upstream Bio, Inc.'s lead drug candidate?
Upstream Bio, Inc.'s most advanced tracked candidate is verekitug (Phase 2) for Chronic Obstructive Pulmonary Disease; Severe Asthma; Chronic Rhinosinusitis With Nasal Polyps.
Who is the CEO of Upstream Bio, Inc.?
Dr. E. Rand Sutherland M.D., M.P.H. is the chief executive officer of Upstream Bio, Inc. (UPB).
Where is Upstream Bio, Inc. headquartered?
Upstream Bio, Inc. (UPB) is headquartered in Waltham, MA, United States.
What therapeutic areas does Upstream Bio, Inc. focus on?
Upstream Bio, Inc. develops therapies across Oncology, Respiratory.
The AI overview and BioSniper Score are neutral, data-derived signals built from public SEC filings, ClinicalTrials.gov and FDA records — not investment advice.