Upstream Bio Reports Q4 and FY2025 Results, Announces Phase 3 Strategy for Verekitug

Key Highlights

• Phase 3 Launch Plan: Upstream Bio will initiate Phase 3 trials for Verekitug in both severe asthma and chronic rhinosinusitis with nasal polyps (CRSwNP) in Q1 2027. The company’s strategy features a high-dose (up to 400 mg) quarterly regimen targeting broad patient populations without biomarker restriction, enabling convenient at-home administration.
• Positive Phase 2 Results: The VALIANT trial in severe asthma (reported February 2026) showed statistically significant reductions in asthma exacerbations and improvements in lung function, with a favorable safety profile. The VIBRANT trial in CRSwNP was presented at AAAAI, reinforcing Verekitug’s efficacy and safety, including significant reductions in nasal polyp burden and symptom scores.
• Strong Financial Position: Cash, cash equivalents, and short-term investments totaled \$341.5 million as of December 31, 2025, expected to fund operations through 2027.
• Ongoing Phase 2 Enrollment in COPD: The VENTURE trial for COPD is over 60% enrolled and designed to generate data for potential regulatory submissions.

Business and Clinical Developments

Upstream Bio (Nasdaq: UPB), a clinical-stage biotech focused on inflammatory diseases, has advanced Verekitug—a monoclonal antibody targeting the thymic stromal lymphopoietin (TSLP) receptor—into late-stage development. Verekitug is positioned as the only known antagonist of the TSLP receptor currently in clinical development, aiming to treat severe asthma, CRSwNP, and COPD.

Phase 3 Strategy: Broad Patient Reach, Quarterly High-Dose Administration

• Analyses from Phase 2 trials support the efficacy and safety of quarterly 400 mg dosing in both severe asthma and CRSwNP.
• Pharmacokinetic modeling predicts near-maximal suppression of exhaled nitric oxide for most patients at doses above 100 mg every 12 weeks.
• Positive responses were observed across both high and low eosinophil subgroups, supporting development in broad populations.
• Immunogenicity was consistent with prior experience; no meaningful efficacy or safety differences were observed in patients with anti-drug antibodies.
• Market research confirms that efficacy remains the primary driver for clinical and commercial success. Healthcare providers prefer quarterly dosing but will not sacrifice efficacy or safety for convenience.
• Regulatory engagement with the FDA is planned for later in 2026; dosing in Phase 3 trials will commence in Q1 2027.

Phase 2 VALIANT (Severe Asthma)

• Statistically significant and clinically meaningful reduction in annualized asthma exacerbation rate (AAER):
  • 56% reduction (p<0.0003) for 100 mg every 12 weeks
  • 39% reduction (p<0.02) for 400 mg every 24 weeks
• Favorable safety profile across all doses tested.

Phase 2 VIBRANT (CRSwNP)

• Presented at AAAAI 2026, reinforcing efficacy and safety:
• 100 mg every 12 weeks met the primary endpoint using both worst-observation carried-forward and primary analyses:
  • Nasal polyp score (NPS) placebo-adjusted reduction: -1.95 (WOCF, p<0.0001); -1.77 (primary, p<0.0001).
  • Nasal congestion score (NCS) placebo-adjusted reduction: -0.96 (WOCF, p<0.0001); -0.77 (primary, p=0.0003).
• Supports ongoing planning for Phase 3 registrational studies.

Phase 2 VENTURE (COPD)

• Global, randomized, placebo-controlled trial; more than 60% enrolled.
• Endpoints designed to support regulatory submissions, pending agency interactions.

Financial Results

• Cash Position: \$341.5 million as of December 31, 2025 (cash, cash equivalents, and short-term investments); expected to fund operations through 2027.
• R&D Expenses: \$40.2 million for Q4 2025 (up from \$21.8 million Q4 2024), primarily driven by increased clinical and manufacturing expenses for Verekitug.
• G&A Expenses: \$6.7 million for Q4 2025 (up from \$5.2 million Q4 2024), due to higher professional fees, personnel, and share-based compensation.
• Net Loss: \$42.5 million for Q4 2025 (up from \$21.2 million Q4 2024), largely due to increased R&D.
• Balance Sheet: Total assets of \$353.8 million, total liabilities of \$14.0 million, and stockholders’ equity of \$339.8 million.

Upcoming Events

• Piper Sandler Spring Biopharma Symposium, April 15-16, Boston, MA
• American Thoracic Society 2026 International Conference, May 15-20, Orlando, FL
• Goldman Sachs 47th Annual Global Healthcare Conference, June 8-10, Miami, FL
• European Academy of Allergy & Clinical Immunology, June 12-16, Istanbul, Turkey

Shareholder Considerations & Potential Price-Sensitive Information

• The initiation of Phase 3 trials for Verekitug in two major indications (severe asthma and CRSwNP), with a high-dose quarterly regimen targeting broad populations, represents a potential inflection point for the company and could be highly price-sensitive.
• Positive Phase 2 efficacy and safety results in both severe asthma and CRSwNP reinforce the differentiation of Verekitug, and if these results are replicated in Phase 3, they could lead to significant market and commercial opportunities.
• The strong financial position ensures the company can fully execute its clinical strategy through 2027 without additional financing, reducing dilution risk.
• Ongoing COPD trial and potential regulatory interactions may unlock further value if successful.
• Investors should monitor for updates on FDA engagement, trial initiation, and further data releases, as these could materially impact share value.

About Upstream Bio

Upstream Bio is a clinical-stage biotechnology company developing Verekitug, a potent monoclonal antibody targeting TSLP, for inflammatory diseases including severe respiratory disorders. The company is committed to addressing unmet needs for patients underserved by current standards of care.

For more information, visit www.upstreambio.com.

Disclaimer

This article contains forward-looking statements based on current information available as of the date of publication. Actual results may differ materially due to risks and uncertainties, including but not limited to clinical trial outcomes, regulatory approvals, and market conditions. Investors should not rely solely on this article for investment decisions and are encouraged to review Upstream Bio’s SEC filings and consult with financial advisors.

View Upstream Bio, Inc. Historical chart here