Upstream Bio's Drug in the FDA Approval Process
This section highlights FDA-related milestones and regulatory updates for drugs developed by Upstream Bio (UPB).
Over the past two years, Upstream Bio has reported clinical trial outcomes, regulatory submissions, approvals, and other FDA events for drugs and therapies such as
Verekitug. For definitions of regulatory abbreviations such as NDA, BLA, or PDUFA, see the event status legend.
Verekitug FDA Regulatory Timeline and Events
Verekitug is a drug developed by Upstream Bio for the following indication: In Chronic Obstructive Pulmonary Disease (COPD).
This drug is under review by the U.S. Food and Drug Administration (FDA).
Below is a timeline of key regulatory milestones for this therapy.
- Drug:
- Verekitug
- Announced Date:
- September 30, 2025
- Indication:
- In Chronic Obstructive Pulmonary Disease (COPD)
Announcement
Upstream Bio, Inc today presented structural and mechanistic data showing verekitug's potent pharmacodynamic activity through its unique approach of targeting the thymic stromal lymphopoietin (TSLP) receptor.
AI Summary
Upstream Bio presented new data showing how verekitug blocks the inflammatory signal TSLP by targeting its receptor. High-resolution crystal structures reveal verekitug binds and occupies key TSLP binding sites on the receptor. Even when the receptor is already paired, verekitug outcompetes TSLP and prevents it from activating the receptor.
Mechanistic studies found that verekitug’s binding strength is extremely high (KD < 1 pM). Pharmacokinetic and pharmacodynamic models suggest the TSLP receptor is less abundant and turns over more slowly than the TSLP protein itself. This combination helps explain why verekitug shows greater potency compared to therapies that only target the TSLP ligand.
These findings support the idea that targeting the TSLP receptor could lead to stronger, longer-lasting effects in severe respiratory diseases. Early clinical trials have already shown rapid and durable receptor inhibition for up to 24 weeks after a dose. Phase 2 top-line data in severe asthma is expected in early 2026.
Read Announcement- Drug:
- Verekitug
- Announced Date:
- September 2, 2025
- Indication:
- In Chronic Obstructive Pulmonary Disease (COPD)
Announcement
Upstream Bio, Inc. announced positive top-line results from the Phase 2 VIBRANT trial evaluating verekitug in participants with chronic rhinosinusitis with nasal polyps (CRSwNP). Verekitug is the only known clinical-stage monoclonal antibody targeting the receptor for thymic stromal lymphopoietin (TSLP).
AI Summary
Upstream Bio, Inc. announced positive top-line results from its Phase 2 VIBRANT trial evaluating verekitug, a new monoclonal antibody medicine, in adults with chronic rhinosinusitis with nasal polyps (CRSwNP). The trial tested whether monthly injections of verekitug could reduce nasal polyps and ease symptoms like congestion and loss of smell.
The study met its primary endpoint by showing a significant drop in total nasal polyp score compared with placebo. Patients also reported improvements on symptom scales, and many saw better breathing and smell recovery. Verekitug was generally safe and well tolerated, with most side effects mild to moderate.
Verekitug is the only clinical-stage antibody known to target the receptor for thymic stromal lymphopoietin (TSLP), a key molecule in airway inflammation. Upstream Bio plans to start Phase 3 studies later this year to confirm these promising results.
Read Announcement- Drug:
- Verekitug
- Announced Date:
- September 1, 2025
- Estimated Event Date Range:
- September 2, 2025 - September 2, 2025
- Target Action Date:
- September 02, 2025
- Indication:
- In Chronic Obstructive Pulmonary Disease (COPD)
Announcement
Upstream Bio, Inc. announced it will report top-line data from the Phase 2 VIBRANT trial of verekitug, the only known clinical-stage monoclonal antibody targeting the receptor for thymic stromal lymphopoietin (TSLP), on Tuesday, September 2, 2025.
AI Summary
Upstream Bio, Inc., a clinical-stage biotechnology company focused on inflammatory and severe respiratory diseases, said it will present top-line data on Tuesday, September 2, 2025, from its Phase 2 VIBRANT trial of verekitug, the only clinical-stage monoclonal antibody targeting the receptor for thymic stromal lymphopoietin (TSLP). TSLP drives inflammation in several immune conditions.
The VIBRANT trial is a global, randomized, placebo-controlled study in adults with chronic rhinosinusitis with nasal polyps (CRSwNP). Participants received 100 mg of verekitug or placebo by subcutaneous injection every 12 weeks for 24 weeks. The primary goal is change in the endoscopic nasal polyp score at Week 24.
Upstream Bio will host a conference call and live webcast on Tuesday, September 2, 2025 at 8:00 a.m. ET to discuss the results. Investors can join the webcast via the Events tab on the company’s website, and a replay will be available afterward.
Read Announcement- Drug:
- Verekitug
- Announced Date:
- July 8, 2025
- Indication:
- In Chronic Obstructive Pulmonary Disease (COPD)
Announcement
Upstream Bio, Inc. announced that the first patient has been dosed in the Company's Phase 2 clinical trial evaluating verekitug in patients with COPD, broadening the global development program for verekitug into a third indication.
AI Summary
Upstream Bio, Inc. announced that the first patient has been dosed in its global Phase 2 VENTURE trial evaluating verekitug for COPD, marking a significant step as the drug enters a third indication. Verekitug is a novel antibody that targets the TSLP receptor, which plays a key role in triggering inflammation. The trial is a randomized, double-blind, placebo-controlled study designed to assess both the efficacy and safety of two dosing regimens—100 mg every 12 weeks and 400 mg every 24 weeks—in approximately 670 adults with moderate-to-severe COPD.
This trial expands the company’s efforts beyond its ongoing studies in severe asthma and chronic rhinosinusitis with nasal polyps. Emerging data suggest that targeting TSLP may offer a differentiated approach to treating COPD, potentially reducing the frequency of exacerbations and improving patient outcomes.
Read Announcement
Upstream Bio FDA Events - Frequently Asked Questions
As of now, Upstream Bio (UPB) has not received any FDA approvals for its therapy in the last two years.
In the past two years, Upstream Bio (UPB) has reported FDA regulatory activity for Verekitug.
The most recent FDA-related event for Upstream Bio occurred on September 30, 2025, involving Verekitug. The update was categorized as "Data," with the company reporting: "Upstream Bio, Inc today presented structural and mechanistic data showing verekitug's potent pharmacodynamic activity through its unique approach of targeting the thymic stromal lymphopoietin (TSLP) receptor."
Currently, Upstream Bio has one therapy (Verekitug) targeting the following condition: In Chronic Obstructive Pulmonary Disease (COPD).
More FDA Event Resources from MarketBeat
FDA Event Stage Terminology & Abbreviation Guide
- NDA: New Drug Application
- ANDA: Abbreviated New Drug Application
- sNDA: Supplemental New Drug Application
- BLA: Biologics License Application
- sBLA: Supplemental Biologics License Application
- FDA Approved: Approved by the FDA
- EMA: European Medicines Agency
- CE Mark: European Union Certification
- NMPA: China National Medical Products Administration
- MHLW: Japanese Ministry of Health
- FDA Meeting: Consultation with FDA
- Pre-IND: Pre-Investigational New Drug Meeting
- Breakthrough Therapy: Special FDA designation for promising therapies
- Fast Track: Accelerated FDA approval pathway
- Orphan Drug: Designation for rare disease treatments
- RPD: Rare Pediatric Disease Designation
- RMAT: Regenerative Medicine Advanced Therapy
- DSMB Review: Data Safety Monitoring Board Review
- IDMC Review: Independent Data Monitoring Committee
- MAA: MHRA Marketing Authorization Application
- RTF: Refusal to File (Rejected Application)
- 510(k): FDA Clearance for Medical Devices
- Rolling Submission: Staggered regulatory review process
This page (NASDAQ:UPB) was last updated on 10/1/2025 by MarketBeat.com Staff
